fix(record): rebase and dto policy

Wait for DOM quiet after actions, match targets to VOM refs, and reduce
drafts into deduped state-linked Trace v3 while keeping the v2 reducer.

Co-authored-by: Cursor <cursoragent@cursor.com>

.github/workflows/release-dsh-plugin.yml

@@ -66,8 +66,8 @@ jobs:
   publish:
     needs: [resolve, guard]
     runs-on: ubuntu-latest
-    # Secret NPM_TOKEN is stored on the GitHub Environment also named NPM_TOKEN.
-    environment: NPM_TOKEN
+    # Secret NPM_TOKEN is stored on the "npm-publish" GitHub Environment.
+    environment: npm-publish
     permissions:
       contents: read
     steps:

AGENT_INSTALL.md

@@ -34,13 +34,17 @@ where only `extension connected` fails is expected; go to Step 3.
 ## 3. Open the extension install page
 
 If `extension connected` is `FAIL` (`0 browsers connected`), the user likely
-has not installed or enabled the browser extension yet. Open the
-[Chrome Web Store install page](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi)
-in the user's browser, then tell the user:
+has not installed or enabled the browser extension yet. Open the install page
+matching the user's browser —
+[Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi)
+for Chrome and other Chromium browsers,
+[Edge Add-ons](https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg)
+for Microsoft Edge — then tell the user:
 
 > Install **BrowserSkill** from the
-> [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi),
-> open the popup, and wait until it turns green. Reply when done.
+> [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi)
+> (or [Edge Add-ons](https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg)
+> on Edge), open the popup, and wait until it turns green. Reply when done.
 
 If opening the page fails, give the user the same link. Then run `bsk doctor`
 once more. All `ok`/`na` → tell the user it's ready.

README.md

@@ -67,7 +67,8 @@ Set up browser-skill on this machine by following https://raw.githubusercontent.
 
 <br>
 
-Install the CLI, then install the extension from the [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi).
+Install the CLI, then install the extension from the [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi)
+or [Edge Add-ons](https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg).
 
 #### 1. Install the `bsk` CLI
 
@@ -91,7 +92,14 @@ bsk --version
 
 #### 2. Install the browser extension
 
-Install BrowserSkill from the [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi).
+Install BrowserSkill from your browser's store:
+
+| Browser | Store listing |
+| --- | --- |
+| Chrome | [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi) |
+| Microsoft Edge | [Edge Add-ons](https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg) |
+
+On other Chromium-based browsers, install the Chrome Web Store build.
 
 #### 3. Install the skill
 
@@ -136,14 +144,24 @@ Start a new Agent session and write a prompt that needs the browser, for example
 
 ## DeepSeek Harness plugin
 
-A [DeepSeek Harness](https://github.com/deepseek-ai/deepseek-harness) plugin that
-injects native `browser_*` tools (no shelling out to `bsk`) and a live Web UI
+Using [DeepSeek Harness](https://github.com/deepseek-ai/deepseek-harness) (`dsh`)?
+BrowserSkill ships a first-class dsh plugin on npm as
+[`@wxg-prc-cpg/browser-skill-dsh-plugin`](https://www.npmjs.com/package/@wxg-prc-cpg/browser-skill-dsh-plugin).
+It injects native `browser_*` tools (no shelling out to `bsk`) and a live Web UI
 overlay of each Agent Window.
 
+Add it to a dsh profile, then start that profile:
+
 ```sh
 dsh plugin --profile web add @wxg-prc-cpg/browser-skill-dsh-plugin
+dsh --profile web
 ```
 
+The plugin carries its own copy of the skill, so `bsk install-skill` is not needed
+for dsh — but the `bsk` CLI and the browser extension are still prerequisites. See
+the [plugin README](packages/dsh-plugin-browserskill/README.md) for the tool list,
+configuration, and the observation overlay.
+
 ## How It Works
 
 BrowserSkill is a local bridge between your agent harness and your browser.

README.zh-CN.md

@@ -54,7 +54,8 @@ BrowserSkill 由两个本地运行组件组成：`bsk` CLI/daemon 和浏览器
 
 <br>
 
-先安装 CLI，再从 [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi) 安装浏览器扩展。
+先安装 CLI，再从 [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi)
+或 [Edge 加载项商店](https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg) 安装浏览器扩展。
 
 #### 1. 安装 `bsk` CLI
 
@@ -64,8 +65,11 @@ BrowserSkill 由两个本地运行组件组成：`bsk` CLI/daemon 和浏览器
 curl -fsSL https://raw.githubusercontent.com/Tencent/BrowserSkill/main/install.sh | sh
 ```
 
-**Windows**：从 [最新 CLI release](https://github.com/Tencent/BrowserSkill/releases/latest)
-下载 `bsk-v<version>-x86_64-pc-windows-msvc.zip`，解压后将 `bsk.exe` 加入 `PATH`。
+**Windows**（PowerShell，安装到 `~/.local/bin`）：
+
+```powershell
+irm https://raw.githubusercontent.com/Tencent/BrowserSkill/main/install.ps1 | iex
+```
 
 验证二进制：
 
@@ -75,7 +79,14 @@ bsk --version
 
 #### 2. 安装浏览器扩展
 
-从 [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi) 安装 BrowserSkill。
+在对应浏览器的商店安装 BrowserSkill：
+
+| 浏览器 | 商店页面 |
+| --- | --- |
+| Chrome | [Chrome Web Store](https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi) |
+| Microsoft Edge | [Edge 加载项商店](https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg) |
+
+其他基于 Chromium 的浏览器，安装 Chrome Web Store 版本即可。
 
 #### 3. 安装 skill
 
@@ -114,12 +125,17 @@ bsk install-skill
 
 ## DeepSeek Harness 插件
 
-[DeepSeek Harness](https://github.com/deepseek-ai/deepseek-harness) 插件：注入原生 `browser_*` 工具（无需再通过 Shell 调用 `bsk`），并在 Web UI 中实时观察每个 Agent Window。
+在用 [DeepSeek Harness](https://github.com/deepseek-ai/deepseek-harness)（`dsh`）？BrowserSkill 提供了官方 dsh 插件，已发布到 npm：[`@wxg-prc-cpg/browser-skill-dsh-plugin`](https://www.npmjs.com/package/@wxg-prc-cpg/browser-skill-dsh-plugin)。它会注入原生 `browser_*` 工具（无需再通过 Shell 调用 `bsk`），并在 Web UI 中实时观察每个 Agent Window。
+
+把它装进某个 dsh profile，然后启动该 profile：
 
 ```sh
 dsh plugin --profile web add @wxg-prc-cpg/browser-skill-dsh-plugin
+dsh --profile web
 ```
 
+插件自带 skill，所以在 dsh 下无需执行 `bsk install-skill`；但 `bsk` CLI 和浏览器扩展仍是前置条件。工具清单、配置项与观察浮层见[插件 README](packages/dsh-plugin-browserskill/README.md)。
+
 ## 工作原理
 
 BrowserSkill 是 Agent 运行时与浏览器之间的本地桥接层。

apps/extension/src/browser-driver/__tests__/chromium-cdp.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it, vi } from "vitest";
-import { type CdpDebuggerApi, ChromiumCdp } from "../chromium-cdp";
+import { type CdpDebuggee, type CdpDebuggerApi, ChromiumCdp } from "../chromium-cdp";
 
 function fakeChromeEvent<TArgs extends unknown[]>() {
   const listeners = new Set<(...args: TArgs) => void>();
@@ -14,7 +14,7 @@ function fakeChromeEvent<TArgs extends unknown[]>() {
 }
 
 function fakeApi() {
-  const onEvent = fakeChromeEvent<[chrome.debugger.Debuggee, string, unknown]>();
+  const onEvent = fakeChromeEvent<[CdpDebuggee, string, unknown]>();
   const onDetach = fakeChromeEvent<[chrome.debugger.Debuggee, string]>();
   const api: CdpDebuggerApi = {
     attach: vi.fn(async () => {}),
@@ -29,6 +29,135 @@ function fakeApi() {
 }
 
 describe("ChromiumCdp", () => {
+  it("discovers multiple iframe targets and recursively routes nested OOPIF commands", async () => {
+    const { api, onEvent } = fakeApi();
+    (api.sendCommand as ReturnType<typeof vi.fn>).mockImplementation(
+      async (
+        target: chrome.debugger.Debuggee & { sessionId?: string },
+        method: string,
+        params?: { frameId?: string },
+      ) => {
+        if (method === "DOM.getFrameOwner") {
+          return { backendNodeId: params?.frameId === "nested" ? 300 : 200 };
+        }
+        if (method !== "Page.getFrameTree") return {};
+        if (target.sessionId === "right-session") {
+          return {
+            frameTree: {
+              frame: { id: "right", url: "https://right.test" },
+              childFrames: [
+                { frame: { id: "nested", parentId: "right", url: "https://nested.test" } },
+              ],
+            },
+          };
+        }
+        if (target.sessionId === "nested-session") {
+          return { frameTree: { frame: { id: "nested", url: "https://nested.test" } } };
+        }
+        return {
+          frameTree: {
+            frame: { id: "main", url: "https://app.test" },
+            childFrames: [
+              { frame: { id: "left", parentId: "main", url: "https://left.test" } },
+              {
+                frame: { id: "right", parentId: "main", url: "https://right.test" },
+                childFrames: [
+                  { frame: { id: "nested", parentId: "right", url: "https://nested.test" } },
+                ],
+              },
+            ],
+          },
+        };
+      },
+    );
+    const cdp = new ChromiumCdp(api);
+    await cdp.ensureAttached(4);
+    onEvent.fire({ tabId: 4 }, "Target.attachedToTarget", { sessionId: "right-session" });
+    onEvent.fire({ tabId: 4 } as chrome.debugger.Debuggee, "Target.attachedToTarget", {
+      sessionId: "nested-session",
+    });
+
+    const graph = await cdp.getFrameGraph(4);
+
+    expect(graph.frames).toHaveLength(4);
+    expect(graph.frames.find((frame) => frame.frameId === "left")?.target).toEqual({ tabId: 4 });
+    expect(graph.frames.find((frame) => frame.frameId === "right")?.target.sessionId).toBe(
+      "right-session",
+    );
+    expect(graph.frames.find((frame) => frame.frameId === "nested")?.target.sessionId).toBe(
+      "nested-session",
+    );
+    expect(graph.frames.find((frame) => frame.frameId === "right")?.ownerBackendNodeId).toBe(200);
+    expect(graph.frames.find((frame) => frame.frameId === "nested")?.ownerBackendNodeId).toBe(300);
+    expect(api.sendCommand).toHaveBeenCalledWith(
+      { tabId: 4, sessionId: "right-session" },
+      "DOM.getFrameOwner",
+      { frameId: "nested" },
+    );
+    expect(api.sendCommand).toHaveBeenCalledWith(
+      { tabId: 4, sessionId: "nested-session" },
+      "Target.setAutoAttach",
+      expect.objectContaining({ flatten: true }),
+    );
+  });
+
+  it("waits for recursively attached iframe targets without a depth limit", async () => {
+    const { api, onEvent } = fakeApi();
+    const depth = 6;
+    const scheduled = new Set<string>();
+    const nestedTree = (index: number): Record<string, unknown> => ({
+      frame: {
+        id: index === 0 ? "main" : `frame-${index}`,
+        ...(index > 0 ? { parentId: index === 1 ? "main" : `frame-${index - 1}` } : {}),
+      },
+      ...(index < depth ? { childFrames: [nestedTree(index + 1)] } : {}),
+    });
+    (api.sendCommand as ReturnType<typeof vi.fn>).mockImplementation(
+      async (target: CdpDebuggee, method: string, params?: { frameId?: string }) => {
+        if (method === "Target.setAutoAttach") {
+          const parentIndex = target.sessionId
+            ? Number(target.sessionId.replace("session-", ""))
+            : 0;
+          const nextIndex = parentIndex + 1;
+          const key = `${target.sessionId ?? "root"}:${nextIndex}`;
+          if (nextIndex <= depth && !scheduled.has(key)) {
+            scheduled.add(key);
+            setTimeout(() => {
+              onEvent.fire(
+                { tabId: 4, ...(target.sessionId ? { sessionId: target.sessionId } : {}) },
+                "Target.attachedToTarget",
+                {
+                  sessionId: `session-${nextIndex}`,
+                  targetInfo: { type: "iframe" },
+                },
+              );
+            }, 5);
+          }
+          return {};
+        }
+        if (method === "Page.getFrameTree") {
+          if (!target.sessionId) return { frameTree: nestedTree(0) };
+          const index = Number(target.sessionId.replace("session-", ""));
+          return { frameTree: nestedTree(index) };
+        }
+        if (method === "DOM.getFrameOwner") {
+          return { backendNodeId: Number(params?.frameId?.replace("frame-", "")) + 100 };
+        }
+        return {};
+      },
+    );
+    const cdp = new ChromiumCdp(api);
+
+    const graph = await cdp.getFrameGraph(4);
+
+    expect(graph.frames).toHaveLength(depth + 1);
+    for (let index = 1; index <= depth; index += 1) {
+      expect(
+        graph.frames.find((frame) => frame.frameId === `frame-${index}`)?.target.sessionId,
+      ).toBe(`session-${index}`);
+    }
+  });
+
   it("coalesces concurrent attach calls for the same tab", async () => {
     const { api } = fakeApi();
     let releaseAttach!: () => void;

apps/extension/src/browser-driver/__tests__/frame-graph.test.ts

@@ -0,0 +1,136 @@
+import { describe, expect, it } from "vitest";
+import { buildFrameGraph, type CdpFrameTreeNode, type CdpFrameTreeSource } from "../frame-graph";
+
+describe("buildFrameGraph", () => {
+  it("keeps sibling frames distinct and routes nested OOPIFs to their child sessions", () => {
+    const graph = buildFrameGraph([
+      {
+        target: { tabId: 4 },
+        tree: {
+          frame: { id: "main", url: "https://app.test" },
+          childFrames: [
+            { frame: { id: "left", parentId: "main", url: "https://left.test" } },
+            {
+              frame: { id: "right", parentId: "main", url: "https://right.test" },
+              childFrames: [
+                { frame: { id: "nested", parentId: "right", url: "https://nested.test" } },
+              ],
+            },
+          ],
+        },
+      },
+      {
+        target: { tabId: 4, sessionId: "right-session" },
+        tree: {
+          frame: { id: "right", url: "https://right.test" },
+          childFrames: [{ frame: { id: "nested", parentId: "right", url: "https://nested.test" } }],
+        },
+      },
+      {
+        target: { tabId: 4, sessionId: "nested-session" },
+        tree: { frame: { id: "nested", url: "https://nested.test" } },
+      },
+    ]);
+
+    expect(graph?.frames).toHaveLength(4);
+    expect(graph?.frames.find((frame) => frame.frameId === "left")?.target).toEqual({ tabId: 4 });
+    expect(graph?.frames.find((frame) => frame.frameId === "right")).toMatchObject({
+      parentFrameId: "main",
+      target: { tabId: 4, sessionId: "right-session" },
+    });
+    expect(graph?.frames.find((frame) => frame.frameId === "nested")).toMatchObject({
+      parentFrameId: "right",
+      target: { tabId: 4, sessionId: "nested-session" },
+    });
+  });
+
+  it("propagates each target boundary to its same-process descendants", () => {
+    const sources: CdpFrameTreeSource[] = [
+      {
+        target: { tabId: 4 },
+        tree: {
+          frame: { id: "main" },
+          childFrames: [
+            {
+              frame: { id: "oopif-a", parentId: "main" },
+              childFrames: [
+                {
+                  frame: { id: "same-process-b", parentId: "oopif-a" },
+                  childFrames: [
+                    {
+                      frame: { id: "oopif-c", parentId: "same-process-b" },
+                      childFrames: [{ frame: { id: "same-process-d", parentId: "oopif-c" } }],
+                    },
+                  ],
+                },
+              ],
+            },
+          ],
+        },
+      },
+      {
+        target: { tabId: 4, sessionId: "session-a" },
+        tree: {
+          frame: { id: "oopif-a" },
+          childFrames: [
+            {
+              frame: { id: "same-process-b", parentId: "oopif-a" },
+              childFrames: [{ frame: { id: "oopif-c", parentId: "same-process-b" } }],
+            },
+          ],
+        },
+      },
+      {
+        target: { tabId: 4, sessionId: "session-c" },
+        tree: {
+          frame: { id: "oopif-c" },
+          childFrames: [{ frame: { id: "same-process-d", parentId: "oopif-c" } }],
+        },
+      },
+    ];
+
+    const graph = buildFrameGraph(sources);
+
+    expect(graph?.frames.map((frame) => [frame.frameId, frame.target.sessionId])).toEqual([
+      ["main", undefined],
+      ["oopif-a", "session-a"],
+      ["same-process-b", "session-a"],
+      ["oopif-c", "session-c"],
+      ["same-process-d", "session-c"],
+    ]);
+    expect(graph?.frames.find((frame) => frame.frameId === "oopif-a")?.parentFrameId).toBe("main");
+    expect(graph?.frames.find((frame) => frame.frameId === "oopif-c")?.parentFrameId).toBe(
+      "same-process-b",
+    );
+
+    const reordered = buildFrameGraph([sources[2], sources[1], sources[0]]);
+    expect(reordered).toEqual(graph);
+  });
+
+  it("walks deeply nested frame trees without consuming the JavaScript call stack", () => {
+    const depth = 5_000;
+    const root: CdpFrameTreeNode = { frame: { id: "frame-0" } };
+    let parent = root;
+    for (let index = 1; index <= depth; index += 1) {
+      const child: CdpFrameTreeNode = {
+        frame: { id: `frame-${index}`, parentId: `frame-${index - 1}` },
+      };
+      parent.childFrames = [child];
+      parent = child;
+    }
+
+    const graph = buildFrameGraph([{ target: { tabId: 4 }, tree: root }]);
+
+    expect(graph?.frames).toHaveLength(depth + 1);
+    expect(graph?.frames.at(-1)?.frameId).toBe(`frame-${depth}`);
+  });
+
+  it("does not loop when an in-memory frame tree contains an object cycle", () => {
+    const root: CdpFrameTreeNode = { frame: { id: "main" } };
+    root.childFrames = [root];
+
+    expect(buildFrameGraph([{ target: { tabId: 4 }, tree: root }])?.frames).toEqual([
+      { frameId: "main", target: { tabId: 4 } },
+    ]);
+  });
+});

apps/extension/src/browser-driver/chromium-cdp.ts

@@ -31,6 +31,15 @@ import type {
   NetworkEntryKind,
   NetworkResult,
 } from "@/transport/types";
+import {
+  buildFrameGraph,
+  type CdpFrameGraph,
+  type CdpFrameTreeNode,
+  type CdpFrameTreeSource,
+  type CdpTarget,
+} from "./frame-graph";
+
+export type CdpDebuggee = chrome.debugger.Debuggee & { sessionId?: string };
 
 /**
  * Minimal slice of `chrome.debugger` the rest of the extension
@@ -38,21 +47,15 @@ import type {
  * fake without monkey-patching the real `chrome` global.
  */
 export interface CdpDebuggerApi {
-  attach(target: chrome.debugger.Debuggee, requiredVersion: string): Promise<void>;
-  detach(target: chrome.debugger.Debuggee): Promise<void>;
-  sendCommand(
-    target: chrome.debugger.Debuggee,
-    method: string,
-    commandParams?: object,
-  ): Promise<unknown>;
+  attach(target: CdpDebuggee, requiredVersion: string): Promise<void>;
+  detach(target: CdpDebuggee): Promise<void>;
+  sendCommand(target: CdpDebuggee, method: string, commandParams?: object): Promise<unknown>;
   /**
    * Fires for every CDP event (`Page.lifecycleEvent`, `DOM.documentUpdated`,
    * …). The first callback argument is the source debuggee; the second
    * is the CDP method name; the third is the payload.
    */
-  onEvent: chrome.events.Event<
-    (source: chrome.debugger.Debuggee, method: string, params: unknown) => void
-  >;
+  onEvent: chrome.events.Event<(source: CdpDebuggee, method: string, params: unknown) => void>;
   /**
    * Fires when Chrome unilaterally detaches us — most commonly because
    * the tab navigated to a chrome:// URL or the user clicked
@@ -110,6 +113,8 @@ const MAX_CONSOLE_STACK_FRAMES = 20;
 const MAX_NETWORK_BUFFER = 200;
 const MAX_NETWORK_FIELD_LENGTH = 4096;
 const MAX_NETWORK_REQUEST_META = 1024;
+const FRAME_DISCOVERY_TIMEOUT_MS = 1000;
+const FRAME_DISCOVERY_QUIET_MS = 20;
 
 interface ParsedDialogOpening {
   type: JavaScriptDialogType;
@@ -131,6 +136,27 @@ interface NetworkRequestMeta {
   truncated: boolean;
 }
 
+interface FrameDiscoveryState {
+  sessions: Set<string>;
+  pending: Set<Promise<void>>;
+  generation: number;
+}
+
+async function settleBeforeDeadline(promises: Promise<void>[], deadline: number): Promise<boolean> {
+  if (promises.length === 0) return true;
+  const remaining = deadline - Date.now();
+  if (remaining <= 0) return false;
+  let timer: ReturnType<typeof setTimeout> | undefined;
+  const timedOut = await Promise.race([
+    Promise.allSettled(promises).then(() => false),
+    new Promise<boolean>((resolve) => {
+      timer = setTimeout(() => resolve(true), remaining);
+    }),
+  ]);
+  if (timer) clearTimeout(timer);
+  return !timedOut;
+}
+
 /**
  * Wrapper around `chrome.debugger` that owns the "attach once per
  * tabId" cache and exposes typed `send<T>()`.
@@ -149,10 +175,12 @@ export class ChromiumCdp {
   private readonly networkSequences = new Map<number, number>();
   private readonly networkDomainsEnabledTabs = new Set<number>();
   private readonly networkRequestMeta = new Map<number, Map<string, NetworkRequestMeta>>();
+  private readonly frameDiscovery = new Map<number, FrameDiscoveryState>();
   private detachSubscription: { dispose(): void } | null = null;
   private dialogSubscription: { dispose(): void } | null = null;
   private consoleSubscription: { dispose(): void } | null = null;
   private networkSubscription: { dispose(): void } | null = null;
+  private frameTargetSubscription: { dispose(): void } | null = null;
 
   constructor(api: CdpDebuggerApi = chromeDebuggerApi) {
     this.api = api;
@@ -160,6 +188,7 @@ export class ChromiumCdp {
     this.bindDialogHandler();
     this.bindConsoleHandler();
     this.bindNetworkHandler();
+    this.bindFrameTargetHandler();
   }
 
   /** Attach to `tabId` if we haven't already in this driver. */
@@ -177,6 +206,9 @@ export class ChromiumCdp {
         await this.enableConsoleDomains(tabId);
         await this.enableNetworkDomainBestEffort(tabId);
         this.attachedTabs.add(tabId);
+        await this.enableFrameDiscovery({ tabId }).catch((err) => {
+          console.debug("[bsk cdp] frame discovery unavailable", { tabId, err });
+        });
       } catch (err) {
         // A CDP domain enable failed after the raw attach succeeded
         // (e.g. `Page.enable` rejects because the tab just navigated to
@@ -222,6 +254,73 @@ export class ChromiumCdp {
     }
   }
 
+  async sendToTarget<T = unknown>(target: CdpTarget, method: string, params?: object): Promise<T> {
+    if (!this.attachedTabs.has(target.tabId)) {
+      await this.ensureAttached(target.tabId);
+    }
+    try {
+      return (await this.api.sendCommand(target, method, params ?? {})) as T;
+    } catch (err) {
+      throw normalizeError(err);
+    }
+  }
+
+  async getFrameGraph(tabId: number): Promise<CdpFrameGraph> {
+    await this.ensureAttached(tabId);
+    await this.enableFrameDiscovery({ tabId }).catch(() => {});
+    await this.drainFrameAttachTasks(tabId);
+
+    const sources: CdpFrameTreeSource[] = [];
+    const root = await this.sendToTarget<{ frameTree?: CdpFrameTreeNode }>(
+      { tabId },
+      "Page.getFrameTree",
+      {},
+    );
+    if (root.frameTree) sources.push({ target: { tabId }, tree: root.frameTree });
+
+    const sessions = [...(this.frameDiscovery.get(tabId)?.sessions ?? [])];
+    const childTrees = await Promise.all(
+      sessions.map(async (sessionId): Promise<CdpFrameTreeSource | null> => {
+        const target = { tabId, sessionId };
+        try {
+          const reply = await this.sendToTarget<{ frameTree?: CdpFrameTreeNode }>(
+            target,
+            "Page.getFrameTree",
+            {},
+          );
+          return reply.frameTree ? { target, tree: reply.frameTree } : null;
+        } catch {
+          return null;
+        }
+      }),
+    );
+    for (const source of childTrees) {
+      if (source) sources.push(source);
+    }
+
+    const graph = buildFrameGraph(sources);
+    if (!graph) throw new Error("Page.getFrameTree returned no root frame");
+    const frameById = new Map(graph.frames.map((frame) => [frame.frameId, frame]));
+    await Promise.all(
+      graph.frames.map(async (frame) => {
+        if (!frame.parentFrameId) return;
+        const parent = frameById.get(frame.parentFrameId);
+        if (!parent) return;
+        try {
+          const owner = await this.sendToTarget<{ backendNodeId?: number }>(
+            parent.target,
+            "DOM.getFrameOwner",
+            { frameId: frame.frameId },
+          );
+          if (owner.backendNodeId !== undefined) frame.ownerBackendNodeId = owner.backendNodeId;
+        } catch {
+          // The frame may have navigated between tree capture and owner lookup.
+        }
+      }),
+    );
+    return graph;
+  }
+
   /** Return a cursor marking the current dialog sequence for `tabId`. */
   dialogCursor(tabId: number): DialogCursor {
     return this.dialogSequences.get(tabId) ?? 0;
@@ -332,6 +431,7 @@ export class ChromiumCdp {
     this.clearDialogState(tabId);
     this.clearConsoleState(tabId);
     this.clearNetworkState(tabId);
+    this.clearFrameState(tabId);
     try {
       await this.api.detach({ tabId });
     } catch (err) {
@@ -354,7 +454,7 @@ export class ChromiumCdp {
   }
 
   /** Subscribe to all CDP events. Returned disposable removes the listener. */
-  onEvent(handler: (source: chrome.debugger.Debuggee, method: string, params: unknown) => void): {
+  onEvent(handler: (source: CdpDebuggee, method: string, params: unknown) => void): {
     dispose(): void;
   } {
     this.api.onEvent.addListener(handler);
@@ -378,6 +478,7 @@ export class ChromiumCdp {
     this.networkSequences.clear();
     this.networkDomainsEnabledTabs.clear();
     this.networkRequestMeta.clear();
+    this.frameDiscovery.clear();
     await Promise.all(
       tabs.map(async (tabId) => {
         try {
@@ -428,9 +529,104 @@ export class ChromiumCdp {
     }
   }
 
+  private async enableFrameDiscovery(target: CdpTarget): Promise<void> {
+    await this.api.sendCommand(target, "Target.setAutoAttach", {
+      autoAttach: true,
+      waitForDebuggerOnStart: false,
+      flatten: true,
+      filter: [{ type: "iframe", exclude: false }],
+    });
+  }
+
+  private bindFrameTargetHandler(): void {
+    if (this.frameTargetSubscription) return;
+    const listener = (source: CdpDebuggee, method: string, params: unknown) => {
+      const tabId = source.tabId;
+      if (typeof tabId !== "number") return;
+      const raw = (params ?? {}) as Record<string, unknown>;
+      const sessionId = typeof raw.sessionId === "string" ? raw.sessionId : undefined;
+      if (!sessionId) return;
+
+      if (method === "Target.detachedFromTarget") {
+        const state = this.frameDiscovery.get(tabId);
+        if (state?.sessions.delete(sessionId)) state.generation += 1;
+        return;
+      }
+      if (method !== "Target.attachedToTarget") return;
+      const targetInfo = raw.targetInfo as { type?: string } | undefined;
+      if (targetInfo?.type && targetInfo.type !== "iframe") return;
+
+      const state = this.frameDiscoveryState(tabId);
+      if (state.sessions.has(sessionId)) return;
+      state.sessions.add(sessionId);
+      state.generation += 1;
+
+      const task = this.initializeFrameTarget({ tabId, sessionId });
+      state.pending.add(task);
+      void task.finally(() => {
+        state.pending.delete(task);
+      });
+    };
+    this.api.onEvent.addListener(listener);
+    this.frameTargetSubscription = {
+      dispose: () => this.api.onEvent.removeListener(listener),
+    };
+  }
+
+  private async initializeFrameTarget(target: CdpTarget): Promise<void> {
+    try {
+      await this.enableFrameDiscovery(target);
+    } catch (err) {
+      const state = this.frameDiscovery.get(target.tabId);
+      if (state?.sessions.delete(target.sessionId as string)) state.generation += 1;
+      console.debug("[bsk cdp] child frame target initialization failed", { target, err });
+    }
+  }
+
+  private async drainFrameAttachTasks(tabId: number): Promise<void> {
+    const deadline = Date.now() + FRAME_DISCOVERY_TIMEOUT_MS;
+    while (Date.now() < deadline) {
+      const state = this.frameDiscovery.get(tabId);
+      const generation = state?.generation ?? 0;
+      if (state?.pending.size && !(await settleBeforeDeadline([...state.pending], deadline))) break;
+
+      // Target.setAutoAttach may enqueue the next attachedToTarget event after
+      // its command promise settles. Wait for a short quiet window, then finish
+      // only if neither the state object nor its generation changed.
+      const quietTime = Math.min(FRAME_DISCOVERY_QUIET_MS, deadline - Date.now());
+      if (quietTime <= 0) break;
+      await new Promise<void>((resolve) => setTimeout(resolve, quietTime));
+      const current = this.frameDiscovery.get(tabId);
+      if (
+        current === state &&
+        (current?.generation ?? 0) === generation &&
+        !current?.pending.size
+      ) {
+        return;
+      }
+    }
+    console.debug("[bsk cdp] frame discovery did not reach quiescence before timeout", { tabId });
+  }
+
+  private frameDiscoveryState(tabId: number): FrameDiscoveryState {
+    const existing = this.frameDiscovery.get(tabId);
+    if (existing) return existing;
+    const created: FrameDiscoveryState = {
+      sessions: new Set(),
+      pending: new Set(),
+      generation: 0,
+    };
+    this.frameDiscovery.set(tabId, created);
+    return created;
+  }
+
+  private clearFrameState(tabId: number): void {
+    this.frameDiscovery.delete(tabId);
+  }
+
   private bindDialogHandler(): void {
     if (this.dialogSubscription) return;
-    const listener = (source: chrome.debugger.Debuggee, method: string, params: unknown) => {
+    const listener = (source: CdpDebuggee, method: string, params: unknown) => {
       if (method !== "Page.javascriptDialogOpening") return;
       const tabId = source.tabId;
       if (typeof tabId !== "number") return;
@@ -614,6 +810,7 @@ export class ChromiumCdp {
         this.clearDialogState(source.tabId);
         this.clearConsoleState(source.tabId);
         this.clearNetworkState(source.tabId);
+        this.clearFrameState(source.tabId);
       }
     };
     this.api.onDetach.addListener(listener);
@@ -632,6 +829,8 @@ export class ChromiumCdp {
     this.consoleSubscription = null;
     this.networkSubscription?.dispose();
     this.networkSubscription = null;
+    this.frameTargetSubscription?.dispose();
+    this.frameTargetSubscription = null;
   }
 
   /** Detach tabs only when no other live session has claimed them. */

apps/extension/src/browser-driver/frame-graph.ts

@@ -0,0 +1,107 @@
+export interface CdpTarget {
+  tabId: number;
+  sessionId?: string;
+}
+
+export interface CdpFrame {
+  frameId: string;
+  parentFrameId?: string;
+  ownerBackendNodeId?: number;
+  url?: string;
+  target: CdpTarget;
+}
+
+export interface CdpFrameGraph {
+  rootFrameId: string;
+  frames: CdpFrame[];
+}
+
+export interface CdpFrameTreeNode {
+  frame: {
+    id: string;
+    parentId?: string;
+    url?: string;
+  };
+  childFrames?: CdpFrameTreeNode[];
+}
+
+export interface CdpFrameTreeSource {
+  target: CdpTarget;
+  tree: CdpFrameTreeNode;
+}
+
+export function cdpTargetKey(target: CdpTarget): string {
+  return `${target.tabId}:${target.sessionId ?? "root"}`;
+}
+
+function mergeFrame(
+  frames: Map<string, CdpFrame>,
+  order: string[],
+  node: CdpFrameTreeNode,
+  target: CdpTarget,
+): void {
+  const existing = frames.get(node.frame.id);
+  if (!existing) order.push(node.frame.id);
+  const parentFrameId = node.frame.parentId || existing?.parentFrameId;
+  const url = node.frame.url || existing?.url;
+  frames.set(node.frame.id, {
+    frameId: node.frame.id,
+    ...(parentFrameId ? { parentFrameId } : {}),
+    ...(url ? { url } : {}),
+    target,
+  });
+}
+
+function walkFrameTree(
+  source: CdpFrameTreeSource,
+  targetByRootFrameId: ReadonlyMap<string, CdpTarget>,
+  frames: Map<string, CdpFrame>,
+  order: string[],
+): void {
+  const stack: Array<{ node: CdpFrameTreeNode; inheritedTarget: CdpTarget }> = [
+    { node: source.tree, inheritedTarget: source.target },
+  ];
+  const expanded = new WeakSet<CdpFrameTreeNode>();
+
+  while (stack.length > 0) {
+    const current = stack.pop();
+    if (!current || expanded.has(current.node)) continue;
+    expanded.add(current.node);
+
+    const target = targetByRootFrameId.get(current.node.frame.id) ?? current.inheritedTarget;
+    mergeFrame(frames, order, current.node, target);
+
+    const children = current.node.childFrames ?? [];
+    for (let index = children.length - 1; index >= 0; index -= 1) {
+      stack.push({ node: children[index], inheritedTarget: target });
+    }
+  }
+}
+
+export function buildFrameGraph(sources: CdpFrameTreeSource[]): CdpFrameGraph | null {
+  const rootSource = sources.find((source) => source.target.sessionId === undefined) ?? sources[0];
+  if (!rootSource) return null;
+
+  const frames = new Map<string, CdpFrame>();
+  const order: string[] = [];
+  const targetByRootFrameId = new Map(
+    sources.map((source) => [source.tree.frame.id, source.target] as const),
+  );
+  // The top-level source is authoritative if malformed input reports the same
+  // frame as both a root target and a child target.
+  targetByRootFrameId.set(rootSource.tree.frame.id, rootSource.target);
+
+  walkFrameTree(rootSource, targetByRootFrameId, frames, order);
+  for (const source of sources) {
+    if (source === rootSource) continue;
+    walkFrameTree(source, targetByRootFrameId, frames, order);
+  }
+
+  return {
+    rootFrameId: rootSource.tree.frame.id,
+    frames: order.flatMap((frameId) => {
+      const frame = frames.get(frameId);
+      return frame ? [frame] : [];
+    }),
+  };
+}

apps/extension/src/content/HelpRequestOverlay.tsx

@@ -8,6 +8,7 @@ import {
   useRef,
   useState,
 } from "react";
+import type { HelpHighlightRect } from "@/lib/help-bridge";
 import logoUrl from "../../assets/logo.png";
 
 export interface HelpRequestData {
@@ -19,6 +20,10 @@ export interface HelpRequestData {
   displayMode?: "full" | "compact";
   /** CSS selectors to scroll to + flash-highlight. */
   selectors: string[];
+  /** Pre-resolved top-viewport rectangles, used for cross-frame targets. */
+  rects?: HelpHighlightRect[];
+  /** Re-resolve cross-frame rectangles after scroll, resize, or layout changes. */
+  refreshRects?: () => Promise<HelpHighlightRect[] | undefined>;
   onContinue: (note: string) => void;
   onCancel: () => void;
 }
@@ -49,6 +54,7 @@ const PANEL_WIDTH = 420;
 const FALLBACK_PANEL_H = 180;
 const FALLBACK_PANEL_H_COLLAPSED = 44;
 const EMPTY_SELECTORS: string[] = [];
+const EMPTY_RECTS: HelpHighlightRect[] = [];
 
 function clamp(value: number, min: number, max: number): number {
   return Math.max(min, Math.min(max, value));
@@ -179,6 +185,8 @@ export function HelpRequestOverlay({ request }: Props) {
   const { t } = useTranslation("extension");
   const isCompact = request?.displayMode === "compact";
   const effectiveSelectors = isCompact ? EMPTY_SELECTORS : (request?.selectors ?? EMPTY_SELECTORS);
+  const [liveRects, setLiveRects] = useState<HelpHighlightRect[] | null>(null);
+  const effectiveRects = isCompact ? EMPTY_RECTS : (liveRects ?? request?.rects ?? EMPTY_RECTS);
   const [note, setNote] = useState("");
   const [collapsed, setCollapsed] = useState(false);
   const [boxes, setBoxes] = useState<Box[]>([]);
@@ -201,6 +209,7 @@ export function HelpRequestOverlay({ request }: Props) {
   // Reset the note and collapse state whenever a new request appears.
   useEffect(() => {
     setNote("");
+    setLiveRects(null);
     setCollapsed(false);
     placementRef.current = null;
     setDragPos(null);
@@ -209,6 +218,32 @@ export function HelpRequestOverlay({ request }: Props) {
     dragStartRef.current = null;
   }, [request?.id]);
 
+  useEffect(() => {
+    if (!request || isCompact || !request.refreshRects) return;
+    let disposed = false;
+    let resolving = false;
+    const refresh = async () => {
+      if (resolving) return;
+      resolving = true;
+      try {
+        const rects = await request.refreshRects?.();
+        if (!disposed && rects) setLiveRects(rects);
+      } finally {
+        resolving = false;
+      }
+    };
+    const onViewportChange = () => void refresh();
+    window.addEventListener("scroll", onViewportChange, true);
+    window.addEventListener("resize", onViewportChange);
+    const interval = window.setInterval(onViewportChange, 500);
+    return () => {
+      disposed = true;
+      window.removeEventListener("scroll", onViewportChange, true);
+      window.removeEventListener("resize", onViewportChange);
+      window.clearInterval(interval);
+    };
+  }, [request, isCompact]);
+
   // Scroll the first matched target into view once per distinct request id.
   useLayoutEffect(() => {
     if (!request) return;
@@ -231,7 +266,7 @@ export function HelpRequestOverlay({ request }: Props) {
       return;
     }
     const update = () => {
-      const nextBoxes = measure(effectiveSelectors);
+      const nextBoxes = [...measure(effectiveSelectors), ...effectiveRects];
       setBoxes((prev) => (boxesEqual(prev, nextBoxes) ? prev : nextBoxes));
     };
     update();
@@ -243,7 +278,7 @@ export function HelpRequestOverlay({ request }: Props) {
       window.removeEventListener("resize", update);
       window.clearInterval(interval);
     };
-  }, [request, effectiveSelectors]);
+  }, [request, effectiveSelectors, effectiveRects]);
 
   const onHeaderPointerDown = useCallback(
     (e: ReactPointerEvent<HTMLDivElement>) => {
@@ -305,7 +340,7 @@ export function HelpRequestOverlay({ request }: Props) {
       return;
     }
     if (userMovedRef.current) return;
-    const measured = boxes.length > 0 ? boxes : measure(effectiveSelectors);
+    const measured = boxes.length > 0 ? boxes : [...measure(effectiveSelectors), ...effectiveRects];
     const anchor = unionBox(measured);
     const banner = bannerRef.current;
     if (!anchor || !banner) {
@@ -329,7 +364,7 @@ export function HelpRequestOverlay({ request }: Props) {
     }
     const nextPos = placePanel(anchor, panelW, panelH, placementRef.current.placement);
     setPanelPos((prev) => (panelPosEqual(prev, nextPos) ? prev : nextPos));
-  }, [request, boxes, collapsed, isCompact, effectiveSelectors]);
+  }, [request, boxes, collapsed, isCompact, effectiveSelectors, effectiveRects]);
 
   if (!request) return null;
 

apps/extension/src/content/__tests__/HelpRequestOverlay.test.tsx

@@ -1,6 +1,6 @@
 import { i18n } from "@browser-skill/i18n";
 import { I18nextProvider } from "@browser-skill/i18n/react";
-import { cleanup, fireEvent, render, screen } from "@testing-library/react";
+import { cleanup, fireEvent, render, screen, waitFor } from "@testing-library/react";
 import { createElement } from "react";
 import { afterEach, describe, expect, it, vi } from "vitest";
 import { type HelpRequestData, HelpRequestOverlay } from "../HelpRequestOverlay";
@@ -38,6 +38,36 @@ describe("HelpRequestOverlay", () => {
     expect(screen.getByText("Please complete the captcha")).toBeTruthy();
   });
 
+  it("renders explicit viewport rectangles for cross-frame targets", () => {
+    const { container } = renderOverlay(
+      baseRequest({ rects: [{ top: 30, left: 40, width: 120, height: 50 }] }),
+    );
+    const highlight = container.querySelector<HTMLElement>("[data-slot='help-highlight']");
+    expect(highlight?.style.top).toBe("30px");
+    expect(highlight?.style.left).toBe("40px");
+    expect(highlight?.style.width).toBe("120px");
+    expect(highlight?.style.height).toBe("50px");
+  });
+
+  it("re-resolves cross-frame rectangles after the viewport changes", async () => {
+    const refreshRects = vi.fn(async () => [{ top: 80, left: 90, width: 140, height: 60 }]);
+    const { container } = renderOverlay(
+      baseRequest({
+        rects: [{ top: 30, left: 40, width: 120, height: 50 }],
+        refreshRects,
+      }),
+    );
+
+    window.dispatchEvent(new Event("scroll"));
+
+    await waitFor(() => {
+      const highlight = container.querySelector<HTMLElement>("[data-slot='help-highlight']");
+      expect(highlight?.style.top).toBe("80px");
+      expect(highlight?.style.left).toBe("90px");
+    });
+    expect(refreshRects).toHaveBeenCalledTimes(1);
+  });
+
   it("keeps the inactive render stable", () => {
     const { container, rerender } = renderOverlay(null);
 

apps/extension/src/content/__tests__/help-request.test.ts

@@ -0,0 +1,64 @@
+import { describe, expect, it, vi } from "vitest";
+import { createHelpRequestData } from "../help-request";
+
+describe("createHelpRequestData", () => {
+  it("gives live delivery and recovery the same rectangle refresh mechanism", async () => {
+    const finish = vi.fn();
+    const query = vi.fn(async () => ({
+      active: true,
+      request: {
+        requestId: "help-1",
+        prompt: "complete the challenge",
+        selectors: [],
+        rects: [{ top: 80, left: 90, width: 140, height: 60 }],
+        timeoutMs: 1_000,
+      },
+    }));
+    const request = createHelpRequestData(
+      {
+        requestId: "help-1",
+        prompt: "complete the challenge",
+        selectors: [],
+        rects: [{ top: 10, left: 20, width: 30, height: 40 }],
+        timeoutMs: 1_000,
+      },
+      { finish, query },
+    );
+
+    await expect(request.refreshRects?.()).resolves.toEqual([
+      { top: 80, left: 90, width: 140, height: 60 },
+    ]);
+    request.onContinue(" done ");
+    request.onCancel();
+
+    expect(query).toHaveBeenCalledOnce();
+    expect(finish).toHaveBeenNthCalledWith(1, "help-1", "continued", " done ");
+    expect(finish).toHaveBeenNthCalledWith(2, "help-1", "cancelled");
+  });
+
+  it("ignores rectangle replies for a replaced request", async () => {
+    const request = createHelpRequestData(
+      {
+        requestId: "help-1",
+        prompt: "complete the challenge",
+        selectors: [],
+        timeoutMs: 1_000,
+      },
+      {
+        finish: vi.fn(),
+        query: vi.fn(async () => ({
+          active: true,
+          request: {
+            requestId: "help-2",
+            prompt: "new challenge",
+            selectors: [],
+            rects: [{ top: 1, left: 2, width: 3, height: 4 }],
+            timeoutMs: 1_000,
+          },
+        })),
+      },
+    );
+
+    await expect(request.refreshRects?.()).resolves.toBeUndefined();
+  });
+});

apps/extension/src/content/help-request.ts

@@ -0,0 +1,31 @@
+import type { HelpQueryResponse, HelpRequestMessage } from "@/lib/help-bridge";
+import type { HelpRequestData } from "./HelpRequestOverlay";
+
+export interface HelpRequestDataDeps {
+  finish(requestId: string, outcome: "continued" | "cancelled", note?: string): void;
+  query(): Promise<HelpQueryResponse | undefined>;
+}
+
+/** Build the content-side representation shared by live delivery and recovery. */
+export function createHelpRequestData(
+  message: Omit<HelpRequestMessage, "type">,
+  deps: HelpRequestDataDeps,
+): HelpRequestData {
+  return {
+    id: message.requestId,
+    prompt: message.prompt,
+    ...(message.title ? { title: message.title } : {}),
+    ...(message.displayMode ? { displayMode: message.displayMode } : {}),
+    selectors: message.selectors,
+    rects: message.rects,
+    refreshRects: async () => {
+      const response = await deps.query();
+      return response?.active && response.request?.requestId === message.requestId
+        ? response.request.rects
+        : undefined;
+    },
+    onContinue: (note: string) =>
+      deps.finish(message.requestId, "continued", note.trim() ? note : undefined),
+    onCancel: () => deps.finish(message.requestId, "cancelled"),
+  };
+}

apps/extension/src/content/record-capture.ts

@@ -1,9 +1,9 @@
 import {
+  type CaptureTargetDescriptor,
   describeEventTarget,
   describeTarget,
   resolveClickableElement,
   resolveHoverElement,
-  type TargetDescriptor,
 } from "@/lib/describe-target";
 import {
   evaluateHoverTrigger,
@@ -27,7 +27,7 @@ import {
   type RecordStopAck,
   type RecordStopMessage,
 } from "@/lib/record-bridge";
-import { shouldRecordPress } from "@/lib/trace-reducer";
+import { shouldRecordPress } from "@/lib/recording/draft-policy";
 import {
   closestHoverSurfaceCandidate,
   collectHoverSurfaceStates,
@@ -65,14 +65,14 @@ export interface RecordCaptureController {
 
 interface FillSession {
   element: FillableElement;
-  target: TargetDescriptor;
+  target: CaptureTargetDescriptor;
   baselineValue: string;
   lastValue: string;
 }
 
 interface HoverCandidate {
   element: Element;
-  target: TargetDescriptor;
+  target: CaptureTargetDescriptor;
   recordedAt: number;
   score: number;
   eligible: boolean;
@@ -232,7 +232,10 @@ function collectHoverTriggerLabelText(root: Element): string {
   return normalizeLabelText(text);
 }
 
-function compactHoverTargetName(el: Element, desc: TargetDescriptor): TargetDescriptor {
+function compactHoverTargetName(
+  el: Element,
+  desc: CaptureTargetDescriptor,
+): CaptureTargetDescriptor {
   if (!desc.name) return desc;
   const fullText = normalizeLabelText(el.textContent ?? "");
   const compactName = collectHoverTriggerLabelText(el);
@@ -250,7 +253,7 @@ function compactHoverTargetName(el: Element, desc: TargetDescriptor): TargetDesc
   return desc;
 }
 
-function isWeakHoverTarget(target: TargetDescriptor): boolean {
+function isWeakHoverTarget(target: CaptureTargetDescriptor): boolean {
   return !target.role && !target.name && target.tag === "div";
 }
 
@@ -261,9 +264,9 @@ function looksLikeAvatarElement(el: Element): boolean {
 
 function normalizeHoverTarget(
   el: Element,
-  desc: TargetDescriptor,
+  desc: CaptureTargetDescriptor,
   decision: HoverTriggerDecision,
-): TargetDescriptor {
+): CaptureTargetDescriptor {
   if (desc.role === "img" && !desc.name && looksLikeAvatarElement(el)) {
     return { ...desc, name: "image" };
   }
@@ -277,7 +280,7 @@ function normalizeHoverTarget(
   return desc;
 }
 
-function hoverTriggerSignals(el: Element, desc: TargetDescriptor) {
+function hoverTriggerSignals(el: Element, desc: CaptureTargetDescriptor) {
   if (!(el instanceof HTMLElement)) return null;
   const style = hoverTriggerStyle(el);
   return {

apps/extension/src/entrypoints/content.ts

@@ -7,6 +7,7 @@ import { BorrowConfirmationOverlay } from "@/content/BorrowConfirmationOverlay";
 import { ControlOverlay } from "@/content/ControlOverlay";
 import { createCaptureSuppressController } from "@/content/capture-suppress";
 import { HelpRequestOverlay } from "@/content/HelpRequestOverlay";
+import { createHelpRequestData } from "@/content/help-request";
 import overlayCss from "@/content/overlay.css?inline";
 import { OverlayController, shouldShowAgentControlOverlay } from "@/content/overlay-controller";
 import { RecordOverlay } from "@/content/RecordOverlay";
@@ -344,16 +345,7 @@ export default defineContentScript({
 
       if (isHelpRequestMessage(message)) {
         const helpMsg = message as HelpRequestMessage;
-        const previousHelp = overlays.setAgentHelpRequest({
-          id: helpMsg.requestId,
-          prompt: helpMsg.prompt,
-          ...(helpMsg.title ? { title: helpMsg.title } : {}),
-          ...(helpMsg.displayMode ? { displayMode: helpMsg.displayMode } : {}),
-          selectors: helpMsg.selectors,
-          onContinue: (note: string) =>
-            void sendHelpFinish(helpMsg.requestId, "continued", note.trim() ? note : undefined),
-          onCancel: () => void sendHelpFinish(helpMsg.requestId, "cancelled"),
-        });
+        const previousHelp = mountHelpRequest(helpMsg);
         if (previousHelp && previousHelp.id !== helpMsg.requestId) {
           void sendHelpFinish(previousHelp.id, "cancelled");
         }
@@ -406,17 +398,18 @@ export default defineContentScript({
       });
     }
 
-    function mountHelpRequest(helpMsg: Omit<HelpRequestMessage, "type">): void {
-      overlays.setAgentHelpRequest({
-        id: helpMsg.requestId,
-        prompt: helpMsg.prompt,
-        ...(helpMsg.title ? { title: helpMsg.title } : {}),
-        ...(helpMsg.displayMode ? { displayMode: helpMsg.displayMode } : {}),
-        selectors: helpMsg.selectors,
-        onContinue: (note: string) =>
-          void sendHelpFinish(helpMsg.requestId, "continued", note.trim() ? note : undefined),
-        onCancel: () => void sendHelpFinish(helpMsg.requestId, "cancelled"),
-      });
+    function mountHelpRequest(helpMsg: Omit<HelpRequestMessage, "type">) {
+      return overlays.setAgentHelpRequest(
+        createHelpRequestData(helpMsg, {
+          finish: (requestId, outcome, note) => {
+            void sendHelpFinish(requestId, outcome, note);
+          },
+          query: () =>
+            chrome.runtime.sendMessage({ type: HELP_QUERY }) as Promise<
+              HelpQueryResponse | undefined
+            >,
+        }),
+      );
     }
 
     async function queryActiveHelpWithRetry(): Promise<void> {

apps/extension/src/lib/__tests__/document-settle.test.ts

@@ -0,0 +1,101 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { CdpRunner } from "@/tools/shared";
+import { waitForDocumentSettled } from "../recording/document-settle";
+
+function quietCdp(): { cdp: CdpRunner; send: ReturnType<typeof vi.fn> } {
+  const send = vi.fn(async () => ({
+    result: { value: { idleMs: 1_000, readyState: "complete" } },
+  }));
+  return {
+    cdp: { send: send as unknown as CdpRunner["send"] },
+    send,
+  };
+}
+
+describe("waitForDocumentSettled", () => {
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
+  it("waits through the minimum observation floor before accepting a quiet page", async () => {
+    vi.useFakeTimers();
+    const { cdp, send } = quietCdp();
+
+    const settled = waitForDocumentSettled(cdp, { target: { tabId: 7 } });
+    await vi.advanceTimersByTimeAsync(180);
+
+    await expect(settled).resolves.toBe("quiet");
+    expect(send).toHaveBeenCalledTimes(3);
+  });
+
+  it("cancels before probing a superseded observation", async () => {
+    vi.useFakeTimers();
+    const { cdp, send } = quietCdp();
+
+    const controller = new AbortController();
+    const settled = waitForDocumentSettled(
+      cdp,
+      { target: { tabId: 7 } },
+      {
+        signal: controller.signal,
+      },
+    );
+    controller.abort();
+    await vi.advanceTimersByTimeAsync(60);
+
+    await expect(settled).resolves.toBe("cancelled");
+    expect(send).not.toHaveBeenCalled();
+  });
+
+  it("probes a same-process iframe through its isolated execution context", async () => {
+    vi.useFakeTimers();
+    const send = vi.fn(async (_tabId: number, method: string) => {
+      if (method === "Page.createIsolatedWorld") return { executionContextId: 91 };
+      return { result: { value: { idleMs: 1_000, readyState: "complete" } } };
+    });
+    const cdp: CdpRunner = { send: send as unknown as CdpRunner["send"] };
+
+    const settled = waitForDocumentSettled(cdp, {
+      target: { tabId: 7 },
+      frameId: "child-frame",
+    });
+    await vi.advanceTimersByTimeAsync(180);
+
+    await expect(settled).resolves.toBe("quiet");
+    expect(send).toHaveBeenCalledWith(
+      7,
+      "Page.createIsolatedWorld",
+      expect.objectContaining({ frameId: "child-frame" }),
+    );
+    expect(send).toHaveBeenCalledWith(
+      7,
+      "Runtime.evaluate",
+      expect.objectContaining({ contextId: 91 }),
+    );
+  });
+
+  it("routes an OOPIF probe through its CDP target session", async () => {
+    vi.useFakeTimers();
+    const send = vi.fn();
+    const sendToTarget = vi.fn(async (_target, method: string) => {
+      if (method === "Page.createIsolatedWorld") return { executionContextId: 27 };
+      return { result: { value: { idleMs: 1_000, readyState: "complete" } } };
+    });
+    const cdp: CdpRunner = {
+      send: send as unknown as CdpRunner["send"],
+      sendToTarget: sendToTarget as unknown as NonNullable<CdpRunner["sendToTarget"]>,
+    };
+
+    const target = { tabId: 7, sessionId: "oopif-session" };
+    const settled = waitForDocumentSettled(cdp, { target, frameId: "oopif-frame" });
+    await vi.advanceTimersByTimeAsync(180);
+
+    await expect(settled).resolves.toBe("quiet");
+    expect(send).not.toHaveBeenCalled();
+    expect(sendToTarget).toHaveBeenCalledWith(
+      target,
+      "Runtime.evaluate",
+      expect.objectContaining({ contextId: 27 }),
+    );
+  });
+});

apps/extension/src/lib/__tests__/help-bridge.test.ts

@@ -32,6 +32,7 @@ describe("help-bridge", () => {
         prompt: "log in",
         displayMode: "compact",
         selectors: ["#login"],
+        rects: [{ top: 10, left: 20, width: 100, height: 40 }],
         timeoutMs: 1000,
       }),
     ).toBe(true);

apps/extension/src/lib/__tests__/recording-observation.test.ts

@@ -0,0 +1,141 @@
+import { describe, expect, it } from "vitest";
+import { ObservationNodeIndex } from "../recording/observation-capture";
+import { RecordingObservationSession } from "../recording/observation-session";
+import { RecordingStateRegistry } from "../recording/state-registry";
+import { buildTraceV3 } from "../recording/trace-builder-v3";
+import type { RecordingDraftStep } from "../recording/types";
+
+const URL = "https://example.com/login";
+
+function sessionWithInput(redactValues = false): RecordingObservationSession {
+  const session = new RecordingObservationSession({ redactValues });
+  const state = session.registry.register({
+    url: URL,
+    rawVomText: '@vom 1\ntextbox "Password" value="••••••" [ref=e1]',
+  });
+  session.cursor.lastSettled = {
+    stateId: state.id,
+    rootFrameId: "root",
+    index: new ObservationNodeIndex({
+      rootFrameId: "root",
+      matchNodes: [
+        {
+          frameId: "root",
+          backendNodeId: 42,
+          tag: "input",
+          rect: { x: 20, y: 40, w: 200, h: 30 },
+          localRect: { x: 20, y: 40, w: 200, h: 30 },
+        },
+      ],
+      refs: [{ ref: "e1", backendNodeId: 42, role: "textbox", name: "Password", line: 1 }],
+    }),
+    url: URL,
+  };
+  return session;
+}
+
+function finalizedFillBody(value: string, redactValues: boolean): string {
+  const session = sessionWithInput(redactValues);
+  const draft: RecordingDraftStep = {
+    op: "fill",
+    captureTarget: { tag: "input", role: "textbox", name: "Password" },
+    value,
+    targetHint: {
+      geometry: { rect: { x: 20, y: 40, w: 200, h: 30 }, tag: "input" },
+    },
+  };
+  session.bindDraft(draft, 1);
+  draft.postStateId = draft.preStateId;
+  return buildTraceV3({
+    registry: session.registry,
+    drafts: [draft],
+    annotations: session.annotations,
+    startedAt: "2026-08-12T00:00:00.000Z",
+    stoppedBy: "user_finish",
+    bskVersion: "test",
+  }).states[0]!.body;
+}
+
+describe("record observation annotations", () => {
+  it("omits a fill literal when values are redacted", () => {
+    const secret = "hunter2-private";
+    const body = finalizedFillBody(secret, true);
+    expect(body).toContain("step 1: fill");
+    expect(body).not.toContain(secret);
+  });
+
+  it("keeps ordinary fill details", () => {
+    expect(finalizedFillBody("ordinary text", false)).toContain('step 1: fill: "ordinary text"');
+  });
+
+  it("encodes title and URL so line breaks cannot corrupt state metadata", () => {
+    const registry = new RecordingStateRegistry();
+    const state = registry.register({
+      url: "https://example.com/a\nb",
+      title: "hello\nworld",
+      rawVomText: "@vom 1",
+    });
+    const trace = buildTraceV3({
+      registry,
+      drafts: [{ op: "scroll", preStateId: state.id, postStateId: state.id }],
+      startedAt: "2026-08-12T00:00:00.000Z",
+      stoppedBy: "user_finish",
+      bskVersion: "test",
+    });
+    expect(trace.states[0]?.body).toContain('url: "https://example.com/a\\nb"');
+    expect(trace.states[0]?.body).toContain('title: "hello\\nworld"');
+  });
+});
+
+describe("recording state ownership", () => {
+  it("deduplicates within one recording and isolates ids between recordings", () => {
+    const first = new RecordingStateRegistry();
+    const second = new RecordingStateRegistry();
+    expect(first.register({ url: URL, rawVomText: "same" }).id).toBe("s1");
+    expect(first.register({ url: URL, rawVomText: "same" }).id).toBe("s1");
+    expect(second.register({ url: URL, rawVomText: "other" }).id).toBe("s1");
+  });
+
+  it("enriches metadata when a deduplicated observation becomes more complete", () => {
+    const registry = new RecordingStateRegistry();
+    registry.register({ url: URL, rawVomText: "same" });
+    const state = registry.register({
+      url: URL,
+      title: "Login",
+      rawVomText: "same",
+      truncated: true,
+    });
+    expect(state).toMatchObject({ id: "s1", title: "Login", truncated: true });
+  });
+});
+
+describe("draft binding", () => {
+  it("keeps capture semantics when no observation exists", () => {
+    const session = new RecordingObservationSession();
+    const draft: RecordingDraftStep = {
+      op: "hover",
+      captureTarget: { tag: "button", role: "button", name: "新建" },
+    };
+    session.bindDraft(draft, 1);
+    expect(draft.matchedTarget).toEqual({ role: "button", name: "新建", unmatched: true });
+    expect(draft.preStateId).toBeUndefined();
+  });
+
+  it("does not bind an unmatched new action to a stale observation", () => {
+    const session = sessionWithInput();
+    const draft: RecordingDraftStep = {
+      op: "click",
+      captureTarget: { tag: "button", role: "button", name: "Confirm" },
+      targetHint: {
+        geometry: { rect: { x: 400, y: 300, w: 80, h: 30 }, tag: "button" },
+      },
+    };
+    session.bindDraft(draft, 2, true);
+    expect(draft.preStateId).toBeUndefined();
+    expect("matchedTarget" in draft ? draft.matchedTarget : undefined).toEqual({
+      role: "button",
+      name: "Confirm",
+      unmatched: true,
+    });
+  });
+});

apps/extension/src/lib/__tests__/settle-controller.test.ts

@@ -0,0 +1,136 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import { ObservationNodeIndex, type RegisteredObservation } from "../recording/observation-capture";
+import { RecordingObservationSession } from "../recording/observation-session";
+import { SettleController } from "../recording/settle-controller";
+import type { RecordingDraftStep } from "../recording/types";
+
+const OBSERVATION: RegisteredObservation = {
+  stateId: "s-next",
+  rootFrameId: "root",
+  index: new ObservationNodeIndex({ rootFrameId: "root", matchNodes: [], refs: [] }),
+  url: "https://example.com/next",
+};
+
+describe("SettleController", () => {
+  afterEach(() => vi.useRealTimers());
+
+  it("aborts superseded capture work and lands the prior action on the next origin", async () => {
+    vi.useFakeTimers();
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({
+        result: { value: { idleMs: 1_000, readyState: "complete" } },
+      })) as unknown as CdpRunner["send"],
+    };
+    const tabsApi: ChromeTabsApi = {
+      get: vi.fn(async () => ({ id: 7, url: OBSERVATION.url }) as chrome.tabs.Tab),
+      query: vi.fn(async () => []),
+    };
+    const session = new RecordingObservationSession();
+    let firstSignal: AbortSignal | undefined;
+    vi.spyOn(session, "capture")
+      .mockImplementationOnce(async (_cdp, _tabs, _tabId, signal) => {
+        firstSignal = signal;
+        return new Promise<RegisteredObservation>((_resolve, reject) => {
+          signal?.addEventListener(
+            "abort",
+            () => reject(new DOMException("observation aborted", "AbortError")),
+            { once: true },
+          );
+        });
+      })
+      .mockResolvedValueOnce(OBSERVATION);
+
+    const drafts: RecordingDraftStep[] = [
+      { op: "click", captureTarget: { tag: "button", name: "First" }, preStateId: "s1" },
+    ];
+    const controller = new SettleController({ session, cdp, tabsApi, tabId: 7 });
+    controller.schedule(drafts, 0);
+    await vi.advanceTimersByTimeAsync(180);
+
+    drafts.push({
+      op: "click",
+      captureTarget: { tag: "button", name: "Second" },
+      preStateId: "s-next",
+    });
+    controller.schedule(drafts, 1);
+    expect(firstSignal?.aborted).toBe(true);
+    expect(drafts[0]?.postStateId).toBe("s-next");
+
+    await vi.advanceTimersByTimeAsync(500);
+    await controller.flush();
+    expect(drafts[1]?.postStateId).toBe("s-next");
+  });
+
+  it("does not consume a newer redirect while reading the prior landing URL", async () => {
+    vi.useFakeTimers();
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({
+        result: { value: { idleMs: 1_000, readyState: "complete" } },
+      })) as unknown as CdpRunner["send"],
+    };
+    let resolveFirstTab!: (tab: chrome.tabs.Tab) => void;
+    const firstTab = new Promise<chrome.tabs.Tab>((resolve) => {
+      resolveFirstTab = resolve;
+    });
+    const tabsApi: ChromeTabsApi = {
+      get: vi
+        .fn()
+        .mockImplementationOnce(() => firstTab)
+        .mockResolvedValue({ id: 7, url: OBSERVATION.url }),
+      query: vi.fn(async () => []),
+    };
+    const session = new RecordingObservationSession();
+    session.cursor.lastSettled = OBSERVATION;
+    const drafts: RecordingDraftStep[] = [];
+    const controller = new SettleController({ session, cdp, tabsApi, tabId: 7 });
+
+    controller.scheduleRedirect(drafts, "https://example.com/intermediate");
+    await vi.advanceTimersByTimeAsync(180);
+    expect(tabsApi.get).toHaveBeenCalledTimes(1);
+
+    controller.scheduleRedirect(drafts, OBSERVATION.url);
+    resolveFirstTab({ id: 7, url: "https://example.com/intermediate" } as chrome.tabs.Tab);
+    await vi.advanceTimersByTimeAsync(500);
+    await controller.flushRedirects();
+
+    expect(drafts).toEqual([]);
+    expect(controller.hasPending).toBe(false);
+  });
+
+  it("settles an action in its own OOPIF document scope", async () => {
+    vi.useFakeTimers();
+    const send = vi.fn();
+    const sendToTarget = vi.fn(async (_target, method: string) => {
+      if (method === "Page.createIsolatedWorld") return { executionContextId: 39 };
+      return { result: { value: { idleMs: 1_000, readyState: "complete" } } };
+    });
+    const cdp: CdpRunner = {
+      send: send as unknown as CdpRunner["send"],
+      sendToTarget: sendToTarget as unknown as NonNullable<CdpRunner["sendToTarget"]>,
+    };
+    const tabsApi: ChromeTabsApi = {
+      get: vi.fn(async () => ({ id: 7, url: OBSERVATION.url }) as chrome.tabs.Tab),
+      query: vi.fn(async () => []),
+    };
+    const session = new RecordingObservationSession();
+    vi.spyOn(session, "capture").mockResolvedValue(OBSERVATION);
+    const drafts: RecordingDraftStep[] = [
+      { op: "click", captureTarget: { tag: "button", name: "Inside frame" } },
+    ];
+    const controller = new SettleController({ session, cdp, tabsApi, tabId: 7 });
+    const target = { tabId: 7, sessionId: "oopif-session" };
+
+    controller.schedule(drafts, 0, { target, frameId: "oopif-frame" });
+    await vi.advanceTimersByTimeAsync(180);
+    await controller.flush();
+
+    expect(send).not.toHaveBeenCalled();
+    expect(sendToTarget).toHaveBeenCalledWith(
+      target,
+      "Runtime.evaluate",
+      expect.objectContaining({ contextId: 39 }),
+    );
+    expect(drafts[0]?.postStateId).toBe("s-next");
+  });
+});

apps/extension/src/lib/__tests__/step-buffer.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { appendRecordedPayload, observeRecordedNavigation } from "../recording-step-buffer";
+import { appendRecordedPayload, observeRecordedNavigation } from "../recording/step-buffer";
 
 describe("recording-step-buffer", () => {
   it("stores semantic click without summary", () => {
@@ -12,7 +12,7 @@ describe("recording-step-buffer", () => {
     expect(buffer.steps).toEqual([
       {
         op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
+        captureTarget: { tag: "button", role: "button", name: "发布" },
       },
     ]);
     expect(buffer.pendingNavigation).toBe(true);
@@ -23,7 +23,7 @@ describe("recording-step-buffer", () => {
       steps: [
         {
           op: "click" as const,
-          target: { tag: "button", role: "button", name: "发布" },
+          captureTarget: { tag: "button", role: "button", name: "发布" },
         },
       ],
       currentUrl: "https://example.com/a",
@@ -34,8 +34,8 @@ describe("recording-step-buffer", () => {
     expect(buffer.steps).toEqual([
       {
         op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
-        navigated_to: "https://example.com/b",
+        captureTarget: { tag: "button", role: "button", name: "发布" },
+        navigatedTo: "https://example.com/b",
       },
     ]);
     expect(JSON.stringify(buffer.steps)).not.toContain("wait_for_navigation");
@@ -46,7 +46,7 @@ describe("recording-step-buffer", () => {
       steps: [
         {
           op: "select" as const,
-          target: { tag: "select", role: "combobox", name: "分类" },
+          captureTarget: { tag: "select", role: "combobox", name: "分类" },
           values: ["tech"],
         },
       ],
@@ -58,9 +58,9 @@ describe("recording-step-buffer", () => {
     expect(buffer.steps).toEqual([
       {
         op: "select",
-        target: { tag: "select", role: "combobox", name: "分类" },
+        captureTarget: { tag: "select", role: "combobox", name: "分类" },
         values: ["tech"],
-        navigated_to: "https://example.com/list?cat=tech",
+        navigatedTo: "https://example.com/list?cat=tech",
       },
     ]);
   });

apps/extension/src/lib/__tests__/target-matcher.test.ts

@@ -0,0 +1,127 @@
+import type { RenderedRef } from "@browser-skill/vom";
+import { describe, expect, it } from "vitest";
+import type { CaptureVomMatchNode } from "@/tools/capture-vom-observation";
+import { ObservationNodeIndex, type RegisteredObservation } from "../recording/observation-capture";
+import { matchObservationTarget } from "../recording/target-matcher";
+
+function node(backendNodeId: number, frameId: string, x = 10): CaptureVomMatchNode {
+  return {
+    backendNodeId,
+    frameId,
+    tag: "button",
+    rect: { x, y: 20, w: 100, h: 30 },
+    localRect: { x, y: 20, w: 100, h: 30 },
+  };
+}
+
+function observation(
+  matchNodes: CaptureVomMatchNode[],
+  refs: RenderedRef[],
+): RegisteredObservation {
+  return {
+    stateId: "s1",
+    rootFrameId: "root",
+    index: new ObservationNodeIndex({ rootFrameId: "root", matchNodes, refs }),
+    url: "https://example.com",
+  };
+}
+
+describe("matchObservationTarget", () => {
+  it("indexes the safe geometry DTO without discarding frame-local geometry", () => {
+    const geometry = node(42, "child");
+    geometry.localRect = { x: 5, y: 6, w: 100, h: 30 };
+    const ref: RenderedRef = {
+      ref: "e1",
+      backendNodeId: 42,
+      frameId: "child",
+      line: 1,
+    };
+    const candidate = observation([geometry], [ref]).index.candidates("child", "button")[0];
+
+    expect(candidate).toEqual({ frameId: "child", geometry, ref });
+  });
+
+  it("matches a unique node using canonical top-level viewport geometry", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root")],
+        [{ ref: "e1", backendNodeId: 42, role: "button", name: "发布", line: 1 }],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+    });
+    expect(target).toEqual({ ref: "e1", role: "button", name: "发布" });
+  });
+
+  it("uses frame id with backend node id so sibling frames cannot collide", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "left"), node(42, "right")],
+        [
+          { ref: "e1", backendNodeId: 42, frameId: "left", line: 1 },
+          { ref: "e2", backendNodeId: 42, frameId: "right", line: 2 },
+        ],
+      ),
+      hint: {
+        frameId: "right",
+        geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+      },
+    });
+    expect(target.ref).toBe("e2");
+  });
+
+  it("restricts a missing frame hint to the root frame", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "child")],
+        [{ ref: "e1", backendNodeId: 42, frameId: "child", line: 1 }],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+      fallback: { tag: "button", name: "发布" },
+    });
+    expect(target).toEqual({ name: "发布", unmatched: true });
+  });
+
+  it("returns unmatched for ambiguous geometry", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root"), node(43, "root")],
+        [
+          { ref: "e1", backendNodeId: 42, line: 1 },
+          { ref: "e2", backendNodeId: 43, line: 2 },
+        ],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+    });
+    expect(target.unmatched).toBe(true);
+  });
+
+  it("uses semantics when geometry is unavailable without crossing frame boundaries", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(41, "root"), node(42, "child")],
+        [
+          { ref: "e1", backendNodeId: 41, role: "button", name: "保存", line: 1 },
+          { ref: "e2", backendNodeId: 42, frameId: "child", role: "button", name: "保存", line: 2 },
+        ],
+      ),
+      hint: { frameId: "child" },
+      fallback: { tag: "button", role: "button", name: "保存" },
+    });
+    expect(target.ref).toBe("e2");
+  });
+
+  it("uses semantics to disambiguate equal geometry in one frame", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root"), node(43, "root")],
+        [
+          { ref: "e1", backendNodeId: 42, role: "button", name: "保存", line: 1 },
+          { ref: "e2", backendNodeId: 43, role: "button", name: "取消", line: 2 },
+        ],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+      fallback: { tag: "button", role: "button", name: "取消" },
+    });
+    expect(target.ref).toBe("e2");
+  });
+});

apps/extension/src/lib/__tests__/trace-reducer-v2.test.ts

@@ -1,6 +1,15 @@
 import { describe, expect, it } from "vitest";
-import type { DraftTraceStep } from "@/transport/types";
-import { reduceTraceSteps, resolveTraceStartUrl, shouldRecordPress } from "../trace-reducer";
+import type { RecordingDraftStep } from "@/lib/recording/types";
+import { shouldRecordPress } from "../recording/draft-policy";
+import { buildTraceV2 } from "../recording/trace-reducer-v2";
+
+function reduceTraceSteps(steps: RecordingDraftStep[], startUrl?: string) {
+  return buildTraceV2({
+    steps,
+    startedAt: "2026-01-01T00:00:00.000Z",
+    ...(startUrl ? { startUrl } : {}),
+  });
+}
 
 describe("shouldRecordPress", () => {
   it("keeps Enter and Escape", () => {
@@ -19,35 +28,35 @@ describe("shouldRecordPress", () => {
 
 describe("reduceTraceSteps", () => {
   it("builds steps with pages dictionary and page id references", () => {
-    const drafts: DraftTraceStep[] = [
+    const drafts: RecordingDraftStep[] = [
       {
         op: "navigate",
         url: "https://example.com/search?q=hello&utm_source=x",
-        page_url: "https://example.com/search?q=hello&utm_source=x",
+        pageUrl: "https://example.com/search?q=hello&utm_source=x",
       },
       {
         op: "fill",
-        target: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
+        captureTarget: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
         value: "browser skill",
-        page_url: "https://example.com/search?q=hello&utm_source=x",
+        pageUrl: "https://example.com/search?q=hello&utm_source=x",
       },
       {
         op: "press",
         key: "Enter",
-        target: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
-        navigated_to: "https://example.com/results/42",
-        page_url: "https://example.com/search?q=hello&utm_source=x",
+        captureTarget: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
+        navigatedTo: "https://example.com/results/42",
+        pageUrl: "https://example.com/search?q=hello&utm_source=x",
       },
       {
         op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
-        navigated_to: "https://example.com/p/99",
-        page_url: "https://example.com/results/42",
+        captureTarget: { tag: "button", role: "button", name: "发布" },
+        navigatedTo: "https://example.com/p/99",
+        pageUrl: "https://example.com/results/42",
       },
       {
         op: "press",
         key: "a",
-        page_url: "https://example.com/p/99",
+        pageUrl: "https://example.com/p/99",
       },
     ];
 
@@ -109,9 +118,9 @@ describe("reduceTraceSteps", () => {
       [
         {
           op: "fill",
-          target: { tag: "input", role: "textbox", name: "Search query" },
+          captureTarget: { tag: "input", role: "textbox", name: "Search query" },
           value: "",
-          page_url: "https://example.com/search",
+          pageUrl: "https://example.com/search",
         },
       ],
       "https://example.com/search",
@@ -125,16 +134,16 @@ describe("reduceTraceSteps", () => {
     ]);
   });
 
-  it("maps select navigated_to onto effect.navigated_to (page id)", () => {
+  it("maps select navigatedTo onto effect.navigatedTo (page id)", () => {
     const { pages, steps } = reduceTraceSteps(
       [
         {
           op: "select",
-          target: { tag: "select", role: "combobox", name: "分类" },
+          captureTarget: { tag: "select", role: "combobox", name: "分类" },
           values: ["tech"],
           labels: ["技术"],
-          navigated_to: "https://example.com/list?cat=tech",
-          page_url: "https://example.com/list",
+          navigatedTo: "https://example.com/list?cat=tech",
+          pageUrl: "https://example.com/list",
         },
       ],
       "https://example.com/list",
@@ -156,13 +165,13 @@ describe("reduceTraceSteps", () => {
       [
         {
           op: "hover",
-          target: { tag: "span", role: "button", name: "Account" },
-          page_url: "https://example.com/app",
+          captureTarget: { tag: "span", role: "button", name: "Account" },
+          pageUrl: "https://example.com/app",
         },
         {
           op: "click",
-          target: { tag: "a", role: "link", name: "Profile" },
-          page_url: "https://example.com/app",
+          captureTarget: { tag: "a", role: "link", name: "Profile" },
+          pageUrl: "https://example.com/app",
         },
       ],
       "https://example.com/app",
@@ -177,10 +186,11 @@ describe("reduceTraceSteps", () => {
 
   it("resolveTraceStartUrl prefers explicit start URL", () => {
     expect(
-      resolveTraceStartUrl(
-        [{ op: "navigate", url: "https://example.com/other" }],
-        "https://example.com/start",
-      ),
+      buildTraceV2({
+        steps: [{ op: "navigate", url: "https://example.com/other" }],
+        startedAt: "2026-01-01T00:00:00.000Z",
+        startUrl: "https://example.com/start",
+      }).entry.start_url,
     ).toBe("https://example.com/start");
   });
 });

apps/extension/src/lib/__tests__/trace-reducer-v3.test.ts

@@ -0,0 +1,62 @@
+import { describe, expect, it } from "vitest";
+import { TRACE_VERSION_V3, VOM_FORMAT_VERSION } from "@/transport/types";
+import { RecordingStateRegistry } from "../recording/state-registry";
+import { buildTraceV3 } from "../recording/trace-builder-v3";
+import { reduceTraceStepsV3 } from "../recording/trace-reducer-v3";
+import type { RecordingDraftStep } from "../recording/types";
+
+describe("trace reducer v3", () => {
+  it("collapses redirect hops while retaining draft-to-step identity", () => {
+    const drafts: RecordingDraftStep[] = [
+      { op: "navigate", url: "https://example.com/start", preStateId: "s1", postStateId: "s2" },
+      {
+        op: "navigate",
+        url: "https://example.com/final",
+        transitionQualifiers: ["server_redirect"],
+        preStateId: "s2",
+        postStateId: "s3",
+      },
+    ];
+    const before = structuredClone(drafts);
+    const reduced = reduceTraceStepsV3(drafts);
+
+    expect(drafts).toEqual(before);
+    expect(reduced.steps).toEqual([
+      expect.objectContaining({
+        id: 1,
+        op: "navigate",
+        state: "s1",
+        to: "https://example.com/final",
+        result: { state: "s3" },
+      }),
+    ]);
+    expect(reduced.stepIdByDraftId.get(1)).toBe(1);
+    expect(reduced.stepIdByDraftId.get(2)).toBe(1);
+  });
+
+  it("builds the wire model from protocol constants", () => {
+    const registry = new RecordingStateRegistry();
+    const state = registry.register({ url: "https://example.com", rawVomText: "@vom 1" });
+    const trace = buildTraceV3({
+      registry,
+      drafts: [
+        {
+          op: "click",
+          captureTarget: { tag: "button", role: "button", name: "Save" },
+          preStateId: state.id,
+          postStateId: state.id,
+        },
+      ],
+      startedAt: "2026-08-12T00:00:00.000Z",
+      stoppedBy: "user_finish",
+      bskVersion: "test",
+    });
+
+    expect(trace.version).toBe(TRACE_VERSION_V3);
+    expect(trace.recorder.vom).toBe(VOM_FORMAT_VERSION);
+    expect(trace.steps[0]).toMatchObject({
+      op: "click",
+      target: { role: "button", name: "Save", unmatched: true },
+    });
+  });
+});

apps/extension/src/lib/describe-target.ts

@@ -1,12 +1,13 @@
 /**
- * Build a semantic TargetDescriptor for an interacted element.
+ * Build a semantic capture descriptor for an interacted element.
  *
  * Trace steps are an LLM *textbook*: each click must say what to look for
  * on screen (usually a short visible name). Tag-only noise like
  * `{ "tag": "div" }` / “点击div” is useless and must not be recorded.
  */
 
-export interface TargetDescriptor {
+/** Content-script capture descriptor before VOM geometric matching. */
+export interface CaptureTargetDescriptor {
   role?: string;
   name?: string;
   tag: string;
@@ -247,7 +248,7 @@ export function resolveHoverElement(target: Element): Element | null {
  * (visible name), or at least a form `name_attr` for checkbox/radio.
  * Recording “点击div” with no name fails this bar.
  */
-export function isMeaningfulClickTarget(target: TargetDescriptor): boolean {
+export function isMeaningfulClickTarget(target: CaptureTargetDescriptor): boolean {
   const name = target.name?.trim();
   if (name && isActionableLabel(name)) return true;
   if (
@@ -323,7 +324,7 @@ function nearbyLabelText(el: Element): string | undefined {
   return undefined;
 }
 
-export function describeTarget(el: Element): TargetDescriptor {
+export function describeTarget(el: Element): CaptureTargetDescriptor {
   const tag = el.tagName.toLowerCase();
   const role = inferRole(el);
   const name = accessibleName(el);
@@ -350,7 +351,7 @@ export function describeTarget(el: Element): TargetDescriptor {
   };
 }
 
-export function describeEventTarget(target: EventTarget | null): TargetDescriptor | null {
+export function describeEventTarget(target: EventTarget | null): CaptureTargetDescriptor | null {
   if (!(target instanceof Element)) return null;
   const clickable = resolveClickableElement(target);
   if (!clickable) return null;

apps/extension/src/lib/help-bridge.ts

@@ -16,6 +16,13 @@ export const HELP_ACK = "bsk-help-ack";
 export const HELP_QUERY = "bsk-help-query";
 export const HELP_FINISH = "bsk-help-finish";
 
+export interface HelpHighlightRect {
+  top: number;
+  left: number;
+  width: number;
+  height: number;
+}
+
 export interface HelpRequestMessage {
   type: typeof HELP_REQUEST;
   requestId: string;
@@ -26,6 +33,8 @@ export interface HelpRequestMessage {
   displayMode?: "full" | "compact";
   /** CSS selectors to scroll to + flash-highlight (may be empty). */
   selectors: string[];
+  /** Top-viewport rectangles for targets that cannot be represented by a root selector. */
+  rects?: HelpHighlightRect[];
   timeoutMs: number;
 }
 
@@ -74,6 +83,16 @@ export function isHelpRequestMessage(msg: unknown): msg is HelpRequestMessage {
     (m.displayMode === undefined || m.displayMode === "full" || m.displayMode === "compact") &&
     Array.isArray(m.selectors) &&
     m.selectors.every((selector) => typeof selector === "string") &&
+    (m.rects === undefined ||
+      (Array.isArray(m.rects) &&
+        m.rects.every(
+          (rect) =>
+            typeof rect === "object" &&
+            rect !== null &&
+            ["top", "left", "width", "height"].every((key) =>
+              Number.isFinite((rect as Record<string, unknown>)[key]),
+            ),
+        ))) &&
     typeof m.timeoutMs === "number"
   );
 }

apps/extension/src/lib/record-bridge.ts

@@ -3,7 +3,7 @@
  * service worker and a tab's content script.
  */
 
-import type { TargetDescriptor } from "./describe-target";
+import type { CaptureTargetDescriptor } from "./describe-target";
 
 export const RECORD_START = "bsk-record-start";
 export const RECORD_STEP = "bsk-record-step";
@@ -42,7 +42,7 @@ export interface RecordStartMessage {
 
 export interface RecordStepPayload {
   op: "click" | "hover" | "fill" | "press" | "select" | "navigate";
-  target?: TargetDescriptor;
+  target?: CaptureTargetDescriptor;
   value?: string;
   key?: string;
   modifiers?: Array<"alt" | "ctrl" | "meta" | "shift">;

apps/extension/src/lib/recording/document-settle.ts

@@ -0,0 +1,134 @@
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import { type CdpRunner, sendToCdpTarget } from "@/tools/shared";
+
+const SETTLE_MIN_MS = 150;
+const SETTLE_QUIET_MS = 250;
+const SETTLE_MAX_MS = 2_000;
+const SETTLE_POLL_MS = 60;
+const SETTLE_WORLD_NAME = "__bsk_record_settle__";
+
+const QUIET_PROBE = `(() => {
+  const scope = window;
+  let probe = scope.__bskRecordQuiet;
+  if (!probe) {
+    probe = { changedAt: Date.now() };
+    const observer = new MutationObserver(() => {
+      probe.changedAt = Date.now();
+    });
+    observer.observe(document.documentElement, {
+      subtree: true,
+      childList: true,
+      attributes: true,
+      characterData: true,
+    });
+    scope.__bskRecordQuiet = probe;
+  }
+  return { idleMs: Date.now() - probe.changedAt, readyState: document.readyState };
+})()`;
+
+export interface DocumentSettleScope {
+  target: CdpTarget;
+  /** Omit only for the target's root document. */
+  frameId?: string;
+}
+
+type SettleOutcome = "quiet" | "timeout" | "cancelled";
+
+interface QuietProbe {
+  idleMs: number;
+  readyState: string;
+}
+
+interface ProbeContext {
+  executionContextId?: number;
+}
+
+function sleep(ms: number, signal?: AbortSignal): Promise<void> {
+  return new Promise((resolve) => {
+    if (signal?.aborted) return resolve();
+    const timer = setTimeout(resolve, ms);
+    signal?.addEventListener(
+      "abort",
+      () => {
+        clearTimeout(timer);
+        resolve();
+      },
+      { once: true },
+    );
+  });
+}
+
+async function executionContextForScope(
+  cdp: CdpRunner,
+  scope: DocumentSettleScope,
+): Promise<number | undefined> {
+  if (!scope.frameId) return undefined;
+  const result = await sendToCdpTarget<{ executionContextId?: number }>(
+    cdp,
+    scope.target,
+    "Page.createIsolatedWorld",
+    {
+      frameId: scope.frameId,
+      worldName: SETTLE_WORLD_NAME,
+      grantUniveralAccess: false,
+    },
+  );
+  return result.executionContextId;
+}
+
+async function readQuietProbe(
+  cdp: CdpRunner,
+  scope: DocumentSettleScope,
+  context: ProbeContext,
+): Promise<QuietProbe | null> {
+  try {
+    if (scope.frameId && context.executionContextId === undefined) {
+      context.executionContextId = await executionContextForScope(cdp, scope);
+      if (context.executionContextId === undefined) return null;
+    }
+    const reply = await sendToCdpTarget<{ result?: { value?: unknown } }>(
+      cdp,
+      scope.target,
+      "Runtime.evaluate",
+      {
+        expression: QUIET_PROBE,
+        returnByValue: true,
+        ...(context.executionContextId !== undefined
+          ? { contextId: context.executionContextId }
+          : {}),
+      },
+    );
+    const value = reply.result?.value;
+    if (!value || typeof value !== "object") return null;
+    const { idleMs, readyState } = value as { idleMs?: unknown; readyState?: unknown };
+    if (typeof idleMs !== "number" || typeof readyState !== "string") return null;
+    return { idleMs, readyState };
+  } catch {
+    context.executionContextId = undefined;
+    return null;
+  }
+}
+
+export async function waitForDocumentSettled(
+  cdp: CdpRunner,
+  scope: DocumentSettleScope,
+  options: { signal?: AbortSignal } = {},
+): Promise<SettleOutcome> {
+  const startedAt = Date.now();
+  const floor = startedAt + SETTLE_MIN_MS;
+  const deadline = startedAt + SETTLE_MAX_MS;
+  const context: ProbeContext = {};
+
+  for (;;) {
+    if (options.signal?.aborted) return "cancelled";
+    await sleep(SETTLE_POLL_MS, options.signal);
+    if (options.signal?.aborted) return "cancelled";
+
+    const probe = await readQuietProbe(cdp, scope, context);
+    const now = Date.now();
+    if (now < floor) continue;
+    if (now >= deadline) return "timeout";
+    if (!probe || probe.readyState === "loading") continue;
+    if (probe.idleMs >= SETTLE_QUIET_MS) return "quiet";
+  }
+}

apps/extension/src/lib/recording/draft-policy.ts

@@ -0,0 +1,34 @@
+import type { RecordingDraftStep } from "./types";
+
+const CLIPBOARD_KEYS = new Set(["a", "c", "v", "x", "A", "C", "V", "X"]);
+const MODIFIER_ONLY_KEYS = new Set(["Meta", "Control", "Alt", "Shift", "OS", "Hyper", "Super"]);
+
+export function shouldRecordPress(
+  key: string,
+  modifiers?: Array<"alt" | "ctrl" | "meta" | "shift">,
+): boolean {
+  if (MODIFIER_ONLY_KEYS.has(key)) return false;
+  const mods = modifiers ?? [];
+  const hasCtrlOrMeta = mods.includes("ctrl") || mods.includes("meta");
+  if (hasCtrlOrMeta && CLIPBOARD_KEYS.has(key)) return false;
+  if (key === "Enter" || key === "Escape") return true;
+  if (key.length === 1 && !hasCtrlOrMeta && !mods.includes("alt")) return false;
+  return false;
+}
+
+export function shouldIncludeDraft(step: RecordingDraftStep): boolean {
+  return step.op !== "press" || shouldRecordPress(step.key, step.modifiers);
+}
+
+export function resolveDraftStartUrl(
+  drafts: RecordingDraftStep[],
+  explicitStartUrl?: string,
+  fallbackUrl?: string,
+): string {
+  if (explicitStartUrl) return explicitStartUrl;
+  const navigation = drafts.find(
+    (step): step is Extract<RecordingDraftStep, { op: "navigate" }> => step.op === "navigate",
+  );
+  if (navigation) return navigation.url;
+  return drafts.find((step) => step.pageUrl)?.pageUrl ?? fallbackUrl ?? "about:blank";
+}

apps/extension/src/lib/recording/observation-capture.ts

@@ -0,0 +1,116 @@
+import type { RenderedRef } from "@browser-skill/vom";
+import {
+  type CaptureVomMatchNode,
+  type CaptureVomObservationResult,
+  captureVomObservation,
+} from "@/tools/capture-vom-observation";
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+
+export interface IndexedObservationNode {
+  frameId: string;
+  geometry: CaptureVomMatchNode;
+  ref?: RenderedRef;
+}
+
+export interface CapturedRecordingObservation {
+  rootFrameId: string;
+  index: ObservationNodeIndex;
+  url: string;
+  title?: string;
+  vomText: string;
+  truncated: boolean;
+}
+
+export interface RegisteredObservation {
+  stateId: string;
+  rootFrameId: string;
+  index: ObservationNodeIndex;
+  url: string;
+}
+
+function nodeKey(frameId: string, backendNodeId: number): string {
+  return `${frameId}:${backendNodeId}`;
+}
+
+function frameTagKey(frameId: string, tag: string): string {
+  return `${frameId}:${tag.toLowerCase()}`;
+}
+
+export class ObservationNodeIndex {
+  readonly #nodesByFrameTag = new Map<string, IndexedObservationNode[]>();
+  readonly #refById = new Map<string, RenderedRef>();
+  readonly #refsByFrame = new Map<string, RenderedRef[]>();
+
+  constructor(input: Pick<CaptureVomObservationResult, "rootFrameId" | "matchNodes" | "refs">) {
+    const refByNode = new Map<string, RenderedRef>();
+    for (const ref of input.refs) {
+      const frameId = ref.frameId ?? input.rootFrameId;
+      refByNode.set(nodeKey(frameId, ref.backendNodeId), ref);
+      this.#refById.set(ref.ref, ref);
+      const frameRefs = this.#refsByFrame.get(frameId) ?? [];
+      frameRefs.push(ref);
+      this.#refsByFrame.set(frameId, frameRefs);
+    }
+    for (const geometry of input.matchNodes) {
+      const { frameId } = geometry;
+      const entry = {
+        frameId,
+        geometry,
+        ref: refByNode.get(nodeKey(frameId, geometry.backendNodeId)),
+      };
+      const key = frameTagKey(frameId, geometry.tag);
+      const bucket = this.#nodesByFrameTag.get(key) ?? [];
+      bucket.push(entry);
+      this.#nodesByFrameTag.set(key, bucket);
+    }
+  }
+
+  candidates(frameId: string, tag: string): readonly IndexedObservationNode[] {
+    return this.#nodesByFrameTag.get(frameTagKey(frameId, tag)) ?? [];
+  }
+
+  ref(refId: string): RenderedRef | undefined {
+    return this.#refById.get(refId);
+  }
+
+  refs(frameId: string): readonly RenderedRef[] {
+    return this.#refsByFrame.get(frameId) ?? [];
+  }
+}
+
+async function readTabMeta(
+  tabsApi: ChromeTabsApi,
+  tabId: number,
+): Promise<{ url: string; title?: string }> {
+  try {
+    const tab = await tabsApi.get(tabId);
+    return { url: tab.url ?? "about:blank", title: tab.title };
+  } catch {
+    return { url: "about:blank" };
+  }
+}
+
+export async function captureRecordingObservation(input: {
+  cdp: CdpRunner;
+  tabsApi: ChromeTabsApi;
+  tabId: number;
+  maxTokens: number;
+  redactValues: boolean;
+  signal?: AbortSignal;
+}): Promise<CapturedRecordingObservation> {
+  const { url, title } = await readTabMeta(input.tabsApi, input.tabId);
+  const captured = await captureVomObservation(input.cdp, input.tabId, url, {
+    maxTokens: input.maxTokens,
+    redactValues: input.redactValues,
+    conditionalSurfaceProbe: false,
+    signal: input.signal,
+  });
+  return {
+    rootFrameId: captured.rootFrameId,
+    index: new ObservationNodeIndex(captured),
+    url,
+    title,
+    vomText: captured.text,
+    truncated: captured.truncated,
+  };
+}

apps/extension/src/lib/recording/observation-session.ts

@@ -0,0 +1,122 @@
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import { captureRecordingObservation, type RegisteredObservation } from "./observation-capture";
+import { RecordingStateRegistry } from "./state-registry";
+import { matchObservationTarget, unmatchedTarget } from "./target-matcher";
+import type { RecordingDraftStep, StepAnnotation, TargetedRecordingDraft } from "./types";
+
+const DEFAULT_MAX_PAGE_TOKENS = 3_000;
+const MIN_CAPTURE_INTERVAL_MS = 200;
+
+export interface TabObservationCursor {
+  lastSettled: RegisteredObservation | null;
+  lastCaptureAt: number;
+}
+
+function abortableDelay(ms: number, signal?: AbortSignal): Promise<void> {
+  return new Promise((resolve) => {
+    if (signal?.aborted) return resolve();
+    const timer = setTimeout(resolve, ms);
+    signal?.addEventListener(
+      "abort",
+      () => {
+        clearTimeout(timer);
+        resolve();
+      },
+      { once: true },
+    );
+  });
+}
+
+function isTargeted(draft: RecordingDraftStep): draft is TargetedRecordingDraft {
+  return draft.op !== "navigate" && draft.op !== "scroll";
+}
+
+export class RecordingObservationSession {
+  readonly registry: RecordingStateRegistry;
+  readonly cursor: TabObservationCursor;
+  readonly annotations: StepAnnotation[];
+  readonly #maxTokens: number;
+  readonly #redactValues: boolean;
+
+  constructor(
+    options: {
+      registry?: RecordingStateRegistry;
+      cursor?: TabObservationCursor;
+      annotations?: StepAnnotation[];
+      maxTokens?: number;
+      redactValues?: boolean;
+    } = {},
+  ) {
+    this.registry = options.registry ?? new RecordingStateRegistry();
+    this.cursor = options.cursor ?? { lastSettled: null, lastCaptureAt: 0 };
+    this.annotations = options.annotations ?? [];
+    this.#maxTokens = options.maxTokens ?? DEFAULT_MAX_PAGE_TOKENS;
+    this.#redactValues = options.redactValues ?? false;
+  }
+
+  async capture(
+    cdp: CdpRunner,
+    tabsApi: ChromeTabsApi,
+    tabId: number,
+    signal?: AbortSignal,
+  ): Promise<RegisteredObservation> {
+    const waitMs = Math.max(0, MIN_CAPTURE_INTERVAL_MS - (Date.now() - this.cursor.lastCaptureAt));
+    if (waitMs > 0) await abortableDelay(waitMs, signal);
+    if (signal?.aborted) throw new DOMException("observation aborted", "AbortError");
+    const captured = await captureRecordingObservation({
+      cdp,
+      tabsApi,
+      tabId,
+      maxTokens: this.#maxTokens,
+      redactValues: this.#redactValues,
+      signal,
+    });
+    const state = this.registry.register({
+      url: captured.url,
+      title: captured.title,
+      rawVomText: captured.vomText,
+      truncated: captured.truncated,
+    });
+    const observation: RegisteredObservation = {
+      stateId: state.id,
+      rootFrameId: captured.rootFrameId,
+      index: captured.index,
+      url: captured.url,
+    };
+    this.cursor.lastSettled = observation;
+    this.cursor.lastCaptureAt = Date.now();
+    return observation;
+  }
+
+  bindDraft(draft: RecordingDraftStep, draftId: number, previousActionPending = false): void {
+    const observation = this.cursor.lastSettled;
+    if (isTargeted(draft)) {
+      draft.matchedTarget = observation
+        ? matchObservationTarget({
+            observation,
+            hint: draft.targetHint,
+            fallback: draft.captureTarget,
+          })
+        : unmatchedTarget(draft.captureTarget);
+    }
+    if (!observation) return;
+
+    const unmatched = isTargeted(draft) && draft.matchedTarget?.unmatched === true;
+    if (previousActionPending && unmatched) return;
+    draft.preStateId = observation.stateId;
+    this.registry.markStep(observation.stateId, draftId);
+
+    if (!isTargeted(draft) || !draft.matchedTarget?.ref) return;
+    const ref = observation.index.ref(draft.matchedTarget.ref);
+    if (!ref) return;
+    this.annotations.push({
+      draftId,
+      op: draft.op,
+      line: ref.line,
+      stateId: observation.stateId,
+      ...(draft.op === "fill" && !this.#redactValues
+        ? { detail: JSON.stringify(draft.value) }
+        : {}),
+    });
+  }
+}

apps/extension/src/lib/recording/settle-controller.ts

@@ -0,0 +1,232 @@
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import { type DocumentSettleScope, waitForDocumentSettled } from "./document-settle";
+import { RecordingObservationSession } from "./observation-session";
+import type { RecordingDraftStep } from "./types";
+
+interface PendingSettle {
+  abort: AbortController;
+  scope: DocumentSettleScope;
+}
+
+interface PendingRedirect {
+  url: string;
+  abort: AbortController;
+}
+
+const CAPTURE_RETRY_DELAY_MS = 250;
+
+function delay(ms: number, signal?: AbortSignal): Promise<void> {
+  return new Promise((resolve) => {
+    if (signal?.aborted) return resolve();
+    const timer = setTimeout(resolve, ms);
+    signal?.addEventListener(
+      "abort",
+      () => {
+        clearTimeout(timer);
+        resolve();
+      },
+      { once: true },
+    );
+  });
+}
+
+function isAbortError(error: unknown): boolean {
+  return (
+    typeof error === "object" &&
+    error !== null &&
+    (error as { name?: string }).name === "AbortError"
+  );
+}
+
+export function inferMissingPostStates(drafts: RecordingDraftStep[]): void {
+  for (let index = 0; index < drafts.length - 1; index += 1) {
+    const draft = drafts[index];
+    const next = drafts[index + 1];
+    if (draft && next && !draft.postStateId && next.preStateId) {
+      draft.postStateId = next.preStateId;
+    }
+  }
+}
+
+export class SettleController {
+  readonly #session: RecordingObservationSession;
+  readonly #cdp: CdpRunner;
+  readonly #tabsApi: ChromeTabsApi;
+  readonly #tabId: number;
+  readonly #rootScope: DocumentSettleScope;
+  readonly #pending = new Map<number, PendingSettle>();
+  #queue = Promise.resolve();
+  #pendingRedirect: PendingRedirect | null = null;
+  #redirectQueue = Promise.resolve();
+
+  constructor(input: {
+    session: RecordingObservationSession;
+    cdp: CdpRunner;
+    tabsApi: ChromeTabsApi;
+    tabId: number;
+  }) {
+    this.#session = input.session;
+    this.#cdp = input.cdp;
+    this.#tabsApi = input.tabsApi;
+    this.#tabId = input.tabId;
+    this.#rootScope = { target: { tabId: input.tabId } };
+  }
+
+  get hasPending(): boolean {
+    return this.#pending.size > 0 || this.#pendingRedirect !== null;
+  }
+
+  async #captureWithRetry(signal?: AbortSignal) {
+    try {
+      return await this.#session.capture(this.#cdp, this.#tabsApi, this.#tabId, signal);
+    } catch (error) {
+      if (signal?.aborted) throw error;
+      await delay(CAPTURE_RETRY_DELAY_MS, signal);
+      return this.#session.capture(this.#cdp, this.#tabsApi, this.#tabId, signal);
+    }
+  }
+
+  schedule(
+    drafts: RecordingDraftStep[],
+    draftIndex: number,
+    scope: DocumentSettleScope = this.#rootScope,
+  ): void {
+    if (scope.target.tabId !== this.#tabId) {
+      throw new Error(
+        `settle scope tab ${scope.target.tabId} does not belong to tab ${this.#tabId}`,
+      );
+    }
+    const landing = drafts[draftIndex]?.preStateId;
+    for (const [index, pending] of this.#pending) {
+      if (index >= draftIndex) continue;
+      pending.abort.abort();
+      this.#pending.delete(index);
+      if (landing && drafts[index] && !drafts[index].postStateId) {
+        drafts[index].postStateId = landing;
+      }
+    }
+
+    this.#pending.get(draftIndex)?.abort.abort();
+    const pending = { abort: new AbortController(), scope };
+    this.#pending.set(draftIndex, pending);
+    const task = async () => {
+      if (pending.abort.signal.aborted) return;
+      try {
+        const outcome = await waitForDocumentSettled(this.#cdp, pending.scope, {
+          signal: pending.abort.signal,
+        });
+        if (outcome === "cancelled") return;
+        const observation = await this.#captureWithRetry(pending.abort.signal);
+        if (!pending.abort.signal.aborted && drafts[draftIndex]) {
+          drafts[draftIndex].postStateId = observation.stateId;
+        }
+      } catch (error) {
+        if (!isAbortError(error)) {
+          console.warn(
+            `[bsk record] post-action observation failed for step ${draftIndex + 1}`,
+            error,
+          );
+        }
+      } finally {
+        if (this.#pending.get(draftIndex) === pending) this.#pending.delete(draftIndex);
+      }
+    };
+    this.#queue = this.#queue.then(task, task).catch(() => {});
+  }
+
+  cancel(): void {
+    for (const pending of this.#pending.values()) pending.abort.abort();
+    this.#pending.clear();
+    this.clearRedirect();
+  }
+
+  async flush(): Promise<void> {
+    for (let round = 0; round < 10; round += 1) {
+      const current = this.#queue;
+      await current;
+      if (current === this.#queue) return;
+    }
+    console.warn("[bsk record] settle queue kept growing; using completed observations");
+  }
+
+  async settleTrailing(drafts: RecordingDraftStep[]): Promise<void> {
+    const trailing: RecordingDraftStep[] = [];
+    for (let index = drafts.length - 1; index >= 0; index -= 1) {
+      const draft = drafts[index];
+      if (!draft || draft.postStateId) break;
+      trailing.push(draft);
+    }
+    if (trailing.length === 0) return;
+    try {
+      const observation = await this.#captureWithRetry();
+      for (const draft of trailing) draft.postStateId = observation.stateId;
+    } catch (error) {
+      console.warn("[bsk record] final observation at stop failed", error);
+    }
+  }
+
+  clearRedirect(): void {
+    this.#pendingRedirect?.abort.abort();
+    this.#pendingRedirect = null;
+  }
+
+  scheduleRedirect(drafts: RecordingDraftStep[], url: string): void {
+    this.#pendingRedirect?.abort.abort();
+    const pending: PendingRedirect = { url, abort: new AbortController() };
+    this.#pendingRedirect = pending;
+    const task = () => this.#settleRedirect(drafts, pending);
+    this.#redirectQueue = this.#redirectQueue.then(task, task).catch(() => {});
+  }
+
+  async #settleRedirect(drafts: RecordingDraftStep[], pending: PendingRedirect): Promise<void> {
+    const outcome = await waitForDocumentSettled(this.#cdp, this.#rootScope, {
+      signal: pending.abort.signal,
+    });
+    if (outcome === "cancelled" || this.#pendingRedirect !== pending) return;
+
+    let finalUrl = pending.url;
+    try {
+      finalUrl = (await this.#tabsApi.get(this.#tabId)).url || finalUrl;
+    } catch {
+      // The navigation event URL remains the best available destination.
+    }
+    if (this.#pendingRedirect !== pending) return;
+    this.#pendingRedirect = null;
+    if (
+      !finalUrl ||
+      finalUrl === "about:blank" ||
+      this.#session.cursor.lastSettled?.url === finalUrl
+    ) {
+      return;
+    }
+
+    const last = drafts[drafts.length - 1];
+    if (last?.op === "navigate" && last.url === finalUrl) {
+      if (!last.postStateId) this.schedule(drafts, drafts.length - 1);
+      await this.flush();
+      return;
+    }
+
+    const draft: RecordingDraftStep = {
+      op: "navigate",
+      url: finalUrl,
+      pageUrl: finalUrl,
+      cause: "browser",
+      preStateId: this.#session.cursor.lastSettled?.stateId,
+    };
+    drafts.push(draft);
+    const draftIndex = drafts.length - 1;
+    if (draft.preStateId) this.#session.registry.markStep(draft.preStateId, draftIndex + 1);
+    this.schedule(drafts, draftIndex);
+    await this.flush();
+  }
+
+  async flushRedirects(): Promise<void> {
+    for (let round = 0; round < 10; round += 1) {
+      const current = this.#redirectQueue;
+      await current;
+      if (current === this.#redirectQueue) return;
+    }
+    console.warn("[bsk record] redirect queue kept growing; using the final completed landing");
+  }
+}

apps/extension/src/lib/recording/state-registry.ts

@@ -0,0 +1,56 @@
+export interface RecordedStateEntry {
+  id: string;
+  url: string;
+  title?: string;
+  rawVomText: string;
+  truncated: boolean;
+  stepsHere: number[];
+}
+
+function stateIdentity(url: string, body: string): string {
+  return `${url}\0${body}`;
+}
+
+export class RecordingStateRegistry {
+  readonly #entriesById = new Map<string, RecordedStateEntry>();
+  readonly #idByIdentity = new Map<string, string>();
+  #nextId = 1;
+
+  register(input: {
+    url: string;
+    title?: string;
+    rawVomText: string;
+    truncated?: boolean;
+  }): RecordedStateEntry {
+    const identity = stateIdentity(input.url, input.rawVomText);
+    const existingId = this.#idByIdentity.get(identity);
+    if (existingId) {
+      const existing = this.#entriesById.get(existingId)!;
+      if (!existing.title && input.title) existing.title = input.title;
+      if (input.truncated) existing.truncated = true;
+      return existing;
+    }
+
+    const entry: RecordedStateEntry = {
+      id: `s${this.#nextId}`,
+      url: input.url,
+      ...(input.title ? { title: input.title } : {}),
+      rawVomText: input.rawVomText,
+      truncated: input.truncated ?? false,
+      stepsHere: [],
+    };
+    this.#nextId += 1;
+    this.#entriesById.set(entry.id, entry);
+    this.#idByIdentity.set(identity, entry.id);
+    return entry;
+  }
+
+  values(): RecordedStateEntry[] {
+    return [...this.#entriesById.values()];
+  }
+
+  markStep(stateId: string, draftId: number): void {
+    const entry = this.#entriesById.get(stateId);
+    if (entry && !entry.stepsHere.includes(draftId)) entry.stepsHere.push(draftId);
+  }
+}

apps/extension/src/lib/recording/step-buffer.ts

@@ -1,8 +1,8 @@
-import type { DraftTraceStep } from "@/transport/types";
-import type { RecordStepPayload } from "./record-bridge";
+import type { RecordStepPayload } from "../record-bridge";
+import type { RecordingDraftStep } from "./types";
 
 export interface RecordingStepBuffer {
-  steps: DraftTraceStep[];
+  steps: RecordingDraftStep[];
   currentUrl?: string;
   pendingNavigation: boolean;
   pendingNavigationDeadline?: number;
@@ -10,33 +10,33 @@ export interface RecordingStepBuffer {
 
 const NAVIGATION_TRIGGER_WINDOW_MS = 3_000;
 
-function toDraftStep(payload: RecordStepPayload): DraftTraceStep | null {
+function toDraftStep(payload: RecordStepPayload): RecordingDraftStep | null {
   const pageUrl = payload.page_url;
   switch (payload.op) {
     case "click":
       return payload.target
         ? {
             op: "click",
-            target: payload.target,
-            ...(pageUrl ? { page_url: pageUrl } : {}),
+            captureTarget: payload.target,
+            ...(pageUrl ? { pageUrl } : {}),
           }
         : null;
     case "hover":
       return payload.target
         ? {
             op: "hover",
-            target: payload.target,
-            ...(pageUrl ? { page_url: pageUrl } : {}),
+            captureTarget: payload.target,
+            ...(pageUrl ? { pageUrl } : {}),
           }
         : null;
     case "fill":
       return payload.target
         ? {
             op: "fill",
-            target: payload.target,
+            captureTarget: payload.target,
             value: payload.value ?? "",
             ...(payload.redacted ? { redacted: true } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
+            ...(pageUrl ? { pageUrl } : {}),
           }
         : null;
     case "press":
@@ -44,19 +44,19 @@ function toDraftStep(payload: RecordStepPayload): DraftTraceStep | null {
         ? {
             op: "press",
             key: payload.key,
-            ...(payload.target ? { target: payload.target } : {}),
+            ...(payload.target ? { captureTarget: payload.target } : {}),
             ...(payload.modifiers?.length ? { modifiers: payload.modifiers } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
+            ...(pageUrl ? { pageUrl } : {}),
           }
         : null;
     case "select":
       return payload.target && payload.values
         ? {
             op: "select",
-            target: payload.target,
+            captureTarget: payload.target,
             values: payload.values,
             ...(payload.labels?.length ? { labels: payload.labels } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
+            ...(pageUrl ? { pageUrl } : {}),
           }
         : null;
     case "navigate":
@@ -69,7 +69,7 @@ function annotateLastStepNavigation(buffer: RecordingStepBuffer, url: string): b
     const step = buffer.steps[i];
     if (!step) continue;
     if (step.op === "click" || step.op === "press" || step.op === "select") {
-      buffer.steps[i] = { ...step, navigated_to: url };
+      buffer.steps[i] = { ...step, navigatedTo: url };
       return true;
     }
     break;
@@ -96,7 +96,7 @@ export function observeRecordedNavigation(
       buffer.steps.push({
         op: "navigate",
         url,
-        page_url: url,
+        pageUrl: url,
       });
     }
     return;
@@ -107,7 +107,7 @@ export function observeRecordedNavigation(
   buffer.steps.push({
     op: "navigate",
     url,
-    page_url: url,
+    pageUrl: url,
   });
 }
 

apps/extension/src/lib/recording/target-matcher.ts

@@ -0,0 +1,76 @@
+import type { RenderedRef } from "@browser-skill/vom";
+import type { TargetDescriptorV3 } from "@/transport/types";
+import type { CaptureTargetDescriptor } from "../describe-target";
+import type { IndexedObservationNode, RegisteredObservation } from "./observation-capture";
+import type { TargetGeometry, TargetMatchHint } from "./types";
+
+const MATCH_TOLERANCE_PX = 2;
+
+function close(a: number, b: number): boolean {
+  return Math.abs(a - b) <= MATCH_TOLERANCE_PX;
+}
+
+function rectMatches(a: TargetGeometry["rect"], b: TargetGeometry["rect"]): boolean {
+  return close(a.x, b.x) && close(a.y, b.y) && close(a.w, b.w) && close(a.h, b.h);
+}
+
+function candidateMatches(candidate: IndexedObservationNode, geometry: TargetGeometry): boolean {
+  return candidate.geometry.rect !== null && rectMatches(geometry.rect, candidate.geometry.rect);
+}
+
+export function unmatchedTarget(fallback?: CaptureTargetDescriptor): TargetDescriptorV3 {
+  return {
+    ...(fallback?.role ? { role: fallback.role } : {}),
+    ...(fallback?.name ? { name: fallback.name } : {}),
+    unmatched: true,
+  };
+}
+
+function normalized(value: string | undefined): string {
+  return value?.replace(/\s+/g, " ").trim().toLowerCase() ?? "";
+}
+
+function matchesSemantics(ref: RenderedRef, fallback?: CaptureTargetDescriptor): boolean {
+  const role = normalized(fallback?.role);
+  const name = normalized(fallback?.name);
+  if (!role && !name) return false;
+  if (role && normalized(ref.role) !== role) return false;
+  if (name && normalized(ref.name) !== name) return false;
+  return true;
+}
+
+function descriptor(ref: RenderedRef): TargetDescriptorV3 {
+  return {
+    ref: ref.ref,
+    ...(ref.role ? { role: ref.role } : {}),
+    ...(ref.name ? { name: ref.name } : {}),
+    ...(ref.ctx ? { ctx: ref.ctx } : {}),
+  };
+}
+
+export function matchObservationTarget(input: {
+  observation: RegisteredObservation;
+  hint?: TargetMatchHint;
+  fallback?: CaptureTargetDescriptor;
+}): TargetDescriptorV3 {
+  const frameId = input.hint?.frameId ?? input.observation.rootFrameId;
+  const geometry = input.hint?.geometry;
+  if (geometry) {
+    const matches = input.observation.index
+      .candidates(frameId, geometry.tag)
+      .filter((candidate) => candidate.ref && candidateMatches(candidate, geometry));
+    if (matches.length === 1) return descriptor(matches[0]!.ref!);
+    const semanticMatches = matches.filter(
+      (candidate) => candidate.ref && matchesSemantics(candidate.ref, input.fallback),
+    );
+    if (semanticMatches.length === 1) return descriptor(semanticMatches[0]!.ref!);
+    return unmatchedTarget(input.fallback);
+  }
+
+  const semanticMatches = input.observation.index
+    .refs(frameId)
+    .filter((ref) => matchesSemantics(ref, input.fallback));
+  return semanticMatches.length === 1
+    ? descriptor(semanticMatches[0]!)
+    : unmatchedTarget(input.fallback);
+}

apps/extension/src/lib/recording/trace-builder-v3.ts

@@ -0,0 +1,87 @@
+import {
+  type StepV3,
+  type StopReason,
+  TRACE_VERSION_V3,
+  type TraceStateV3,
+  type TraceV3,
+  VOM_FORMAT_VERSION,
+} from "@/transport/types";
+import { resolveDraftStartUrl } from "./draft-policy";
+import type { RecordedStateEntry, RecordingStateRegistry } from "./state-registry";
+import { reduceTraceStepsV3 } from "./trace-reducer-v3";
+import { formatTraceStateBody } from "./trace-state-body";
+import type { RecordingDraftStep, StepAnnotation } from "./types";
+
+function publishedEntries(registry: RecordingStateRegistry, steps: StepV3[]): RecordedStateEntry[] {
+  const entries = registry.values();
+  if (steps.length === 0) return entries.slice(0, 1);
+  const referenced = new Set(steps.flatMap((step) => [step.state, step.result.state]));
+  return entries.filter((entry) => referenced.has(entry.id));
+}
+
+function remapDraftIds(draftIds: number[], stepIdByDraftId: Map<number, number>): number[] {
+  return [
+    ...new Set(
+      draftIds.flatMap((id) => {
+        const stepId = stepIdByDraftId.get(id);
+        return stepId === undefined ? [] : [stepId];
+      }),
+    ),
+  ].sort((a, b) => a - b);
+}
+
+export function buildTraceV3(input: {
+  registry: RecordingStateRegistry;
+  drafts: RecordingDraftStep[];
+  annotations?: StepAnnotation[];
+  startedAt: string;
+  purpose?: string;
+  startUrl?: string;
+  stoppedBy: StopReason;
+  bskVersion: string;
+}): TraceV3 {
+  const reduced = reduceTraceStepsV3(input.drafts);
+  const entries = publishedEntries(input.registry, reduced.steps);
+  const publishedId = new Map(entries.map((entry, index) => [entry.id, `s${index + 1}`]));
+  const annotationsByState = new Map<string, StepAnnotation[]>();
+  for (const annotation of input.annotations ?? []) {
+    const bucket = annotationsByState.get(annotation.stateId) ?? [];
+    bucket.push(annotation);
+    annotationsByState.set(annotation.stateId, bucket);
+  }
+  const steps = reduced.steps.map((step) => ({
+    ...step,
+    state: publishedId.get(step.state) ?? step.state,
+    result: { state: publishedId.get(step.result.state) ?? step.result.state },
+  }));
+  const states: TraceStateV3[] = entries.map((entry) => {
+    const id = publishedId.get(entry.id) ?? entry.id;
+    return {
+      id,
+      url: entry.url,
+      ...(entry.title ? { title: entry.title } : {}),
+      body: formatTraceStateBody({
+        stateId: id,
+        url: entry.url,
+        title: entry.title,
+        stepIds: remapDraftIds(entry.stepsHere, reduced.stepIdByDraftId),
+        vomText: entry.rawVomText,
+        annotations: annotationsByState.get(entry.id) ?? [],
+        stepIdByDraftId: reduced.stepIdByDraftId,
+      }),
+      ...(entry.truncated ? { truncated: true } : {}),
+    };
+  });
+
+  return {
+    version: TRACE_VERSION_V3,
+    ...(input.purpose ? { purpose: input.purpose } : {}),
+    recorded_at: new Date().toISOString(),
+    started_at: input.startedAt,
+    stopped_by: input.stoppedBy,
+    entry: { start_url: resolveDraftStartUrl(input.drafts, input.startUrl, states[0]?.url) },
+    recorder: { bsk: input.bskVersion, vom: VOM_FORMAT_VERSION },
+    states,
+    steps,
+  };
+}

apps/extension/src/lib/recording/trace-reducer-v2.ts

@@ -1,30 +1,10 @@
-import type { DraftTraceStep, PageRef, SelectedOption, Step } from "@/transport/types";
-
-const CLIPBOARD_KEYS = new Set(["a", "c", "v", "x", "A", "C", "V", "X"]);
-const MODIFIER_ONLY_KEYS = new Set(["Meta", "Control", "Alt", "Shift", "OS", "Hyper", "Super"]);
-
-export function shouldRecordPress(
-  key: string,
-  modifiers?: Array<"alt" | "ctrl" | "meta" | "shift">,
-): boolean {
-  if (MODIFIER_ONLY_KEYS.has(key)) return false;
-  const mods = modifiers ?? [];
-  const hasCtrlOrMeta = mods.includes("ctrl") || mods.includes("meta");
-  if (hasCtrlOrMeta && CLIPBOARD_KEYS.has(key)) return false;
-  if (key === "Enter" || key === "Escape") return true;
-  // Drop bare character typing — FillSession already records the value.
-  if (key.length === 1 && !hasCtrlOrMeta && !mods.includes("alt")) return false;
-  return false;
-}
-
-function shouldIncludeDraft(step: DraftTraceStep): boolean {
-  if (step.op === "press" && !shouldRecordPress(step.key, step.modifiers)) return false;
-  return true;
-}
+import type { PageRefV2, SelectedOptionV2, StepV2, TraceV2 } from "@/transport/types";
+import { resolveDraftStartUrl, shouldIncludeDraft } from "./draft-policy";
+import type { RecordingDraftStep } from "./types";
 
 /** Collapse consecutive navigations to the last hop. */
-function collapseNavigations(steps: DraftTraceStep[]): DraftTraceStep[] {
-  const out: DraftTraceStep[] = [];
+function collapseNavigations(steps: RecordingDraftStep[]): RecordingDraftStep[] {
+  const out: RecordingDraftStep[] = [];
   for (const step of steps) {
     const prev = out[out.length - 1];
     if (step.op === "navigate" && prev?.op === "navigate") {
@@ -36,7 +16,7 @@ function collapseNavigations(steps: DraftTraceStep[]): DraftTraceStep[] {
   return out;
 }
 
-function collectUrls(steps: DraftTraceStep[], startUrl?: string): string[] {
+function collectUrls(steps: RecordingDraftStep[], startUrl?: string): string[] {
   const urls: string[] = [];
   if (startUrl) urls.push(startUrl);
   for (const step of steps) {
@@ -44,8 +24,8 @@ function collectUrls(steps: DraftTraceStep[], startUrl?: string): string[] {
       urls.push(step.url);
       continue;
     }
-    if ("page_url" in step && step.page_url) urls.push(step.page_url);
-    if ("navigated_to" in step && step.navigated_to) urls.push(step.navigated_to);
+    if (step.pageUrl) urls.push(step.pageUrl);
+    if ("navigatedTo" in step && step.navigatedTo) urls.push(step.navigatedTo);
   }
   const seen = new Set<string>();
   const unique: string[] = [];
@@ -58,9 +38,9 @@ function collectUrls(steps: DraftTraceStep[], startUrl?: string): string[] {
 }
 
 function buildPageRegistry(
-  steps: DraftTraceStep[],
+  steps: RecordingDraftStep[],
   startUrl?: string,
-): { pages: PageRef[]; urlToId: Map<string, string> } {
+): { pages: PageRefV2[]; urlToId: Map<string, string> } {
   const urls = collectUrls(steps, startUrl);
   const urlToId = new Map<string, string>();
   const pages = urls.map((url, index) => {
@@ -81,28 +61,28 @@ function pageIdFor(
   return urlToId.values().next().value ?? "p1";
 }
 
-function pageUrlForDraft(step: DraftTraceStep, fallbackUrl?: string): string | undefined {
-  if (step.op === "navigate") return step.page_url ?? step.url;
-  if ("page_url" in step && step.page_url) return step.page_url;
+function pageUrlForDraft(step: RecordingDraftStep, fallbackUrl?: string): string | undefined {
+  if (step.op === "navigate") return step.pageUrl ?? step.url;
+  if (step.pageUrl) return step.pageUrl;
   return fallbackUrl;
 }
 
 function effectForNavigation(
   navigatedTo: string | undefined,
   urlToId: Map<string, string>,
-): Step["effect"] {
+): StepV2["effect"] {
   if (!navigatedTo) return undefined;
   const pageId = urlToId.get(navigatedTo);
   if (!pageId) return undefined;
   return { navigated_to: pageId };
 }
 
-function withEffect(step: Step, effect: Step["effect"]): Step {
+function withEffect(step: StepV2, effect: StepV2["effect"]): StepV2 {
   if (!effect) return step;
   return { ...step, effect };
 }
 
-function toSelection(values: string[], labels?: string[]): SelectedOption[] {
+function toSelection(values: string[], labels?: string[]): SelectedOptionV2[] {
   return values.map((value, index) => ({
     value,
     ...(labels?.[index] ? { label: labels[index] } : {}),
@@ -110,11 +90,11 @@ function toSelection(values: string[], labels?: string[]): SelectedOption[] {
 }
 
 function toV2Step(
-  step: DraftTraceStep,
+  step: RecordingDraftStep,
   id: number,
   urlToId: Map<string, string>,
   fallbackUrl?: string,
-): Step | null {
+): StepV2 | null {
   if (!shouldIncludeDraft(step)) return null;
 
   const pageUrl = pageUrlForDraft(step, fallbackUrl);
@@ -129,28 +109,31 @@ function toV2Step(
         to: step.url,
       };
     case "click":
+      if (!step.captureTarget) return null;
       return withEffect(
         {
           op: "click",
           id,
           page,
-          target: step.target,
+          target: step.captureTarget,
         },
-        effectForNavigation(step.navigated_to, urlToId),
+        effectForNavigation(step.navigatedTo, urlToId),
       );
     case "hover":
+      if (!step.captureTarget) return null;
       return {
         op: "hover",
         id,
         page,
-        target: step.target,
+        target: step.captureTarget,
       };
     case "fill":
+      if (!step.captureTarget) return null;
       return {
         op: "fill",
         id,
         page,
-        target: step.target,
+        target: step.captureTarget,
         value: step.value,
         ...(step.redacted ? { redacted: true } : {}),
       };
@@ -161,44 +144,47 @@ function toV2Step(
           id,
           page,
           key: step.key,
-          ...(step.target ? { target: step.target } : {}),
+          ...(step.captureTarget ? { target: step.captureTarget } : {}),
           ...(step.modifiers?.length ? { modifiers: step.modifiers } : {}),
         },
-        effectForNavigation(step.navigated_to, urlToId),
+        effectForNavigation(step.navigatedTo, urlToId),
       );
     case "select":
+      if (!step.captureTarget) return null;
       return withEffect(
         {
           op: "select",
           id,
           page,
-          target: step.target,
+          target: step.captureTarget,
           selection: toSelection(step.values, step.labels),
         },
-        effectForNavigation(step.navigated_to, urlToId),
+        effectForNavigation(step.navigatedTo, urlToId),
       );
+    case "scroll":
+      return null;
   }
 }
 
-export interface ReducedTrace {
-  pages: PageRef[];
-  steps: Step[];
+interface ReducedTrace {
+  pages: PageRefV2[];
+  steps: StepV2[];
 }
 
 /**
  * Compile capture drafts into record-only trace v2 steps.
  * Variable inputs are NOT classified here — executing agents infer that at run time.
  */
-export function reduceTraceSteps(steps: DraftTraceStep[], startUrl?: string): ReducedTrace {
+function reduceTraceSteps(steps: RecordingDraftStep[], startUrl?: string): ReducedTrace {
   const collapsed = collapseNavigations(steps);
   const { pages, urlToId } = buildPageRegistry(collapsed, startUrl);
-  const out: Step[] = [];
+  const out: StepV2[] = [];
   let id = 1;
   let lastUrl = startUrl;
   for (const draft of collapsed) {
     if (draft.op === "navigate") lastUrl = draft.url;
-    else if ("navigated_to" in draft && draft.navigated_to) lastUrl = draft.navigated_to;
-    else if ("page_url" in draft && draft.page_url) lastUrl = draft.page_url;
+    else if ("navigatedTo" in draft && draft.navigatedTo) lastUrl = draft.navigatedTo;
+    else if (draft.pageUrl) lastUrl = draft.pageUrl;
     const step = toV2Step(draft, id, urlToId, lastUrl);
     if (!step) continue;
     out.push(step);
@@ -207,18 +193,27 @@ export function reduceTraceSteps(steps: DraftTraceStep[], startUrl?: string): Re
   return { pages, steps: out };
 }
 
-export function resolveTraceStartUrl(
-  drafts: DraftTraceStep[],
+function resolveTraceStartUrl(
+  drafts: RecordingDraftStep[],
   startUrl?: string,
-  pages?: PageRef[],
+  pages?: PageRefV2[],
 ): string {
-  if (startUrl) return startUrl;
-  const navigate = drafts.find((step): step is Extract<DraftTraceStep, { op: "navigate" }> => {
-    return step.op === "navigate";
-  });
-  if (navigate) return navigate.url;
-  for (const draft of drafts) {
-    if ("page_url" in draft && draft.page_url) return draft.page_url;
-  }
-  return pages?.[0]?.url ?? "about:blank";
+  return resolveDraftStartUrl(drafts, startUrl, pages?.[0]?.url);
+}
+
+export function buildTraceV2(input: {
+  steps: RecordingDraftStep[];
+  startedAt: string;
+  startUrl?: string;
+  purpose?: string;
+}): TraceV2 {
+  const { pages, steps } = reduceTraceSteps(input.steps, input.startUrl);
+  return {
+    recorded_at: new Date().toISOString(),
+    started_at: input.startedAt,
+    ...(input.purpose ? { purpose: input.purpose } : {}),
+    entry: { start_url: resolveTraceStartUrl(input.steps, input.startUrl, pages) },
+    pages,
+    steps,
+  };
 }

apps/extension/src/lib/recording/trace-reducer-v3.ts

@@ -0,0 +1,129 @@
+import type { NavigationCause, StepV3 } from "@/transport/types";
+import { shouldIncludeDraft } from "./draft-policy";
+import { unmatchedTarget } from "./target-matcher";
+import type { RecordingDraftStep } from "./types";
+
+interface CollapsedDraft {
+  draft: RecordingDraftStep;
+  draftIds: number[];
+}
+
+const REDIRECT_QUALIFIERS = new Set(["client_redirect", "server_redirect"]);
+const TRANSITION_CAUSES: Record<string, NavigationCause> = {
+  typed: "user_typed",
+  generated: "user_typed",
+  keyword: "user_typed",
+  keyword_generated: "user_typed",
+  link: "link",
+  form_submit: "form_submit",
+  reload: "reload",
+  auto_bookmark: "browser",
+  start_page: "browser",
+};
+
+function isRedirect(step: Extract<RecordingDraftStep, { op: "navigate" }>): boolean {
+  return (step.transitionQualifiers ?? []).some((qualifier) => REDIRECT_QUALIFIERS.has(qualifier));
+}
+
+function collapseRedirects(steps: RecordingDraftStep[]): CollapsedDraft[] {
+  const output: CollapsedDraft[] = [];
+  steps.forEach((step, index) => {
+    const previous = output[output.length - 1];
+    if (step.op === "navigate" && previous?.draft.op === "navigate" && isRedirect(step)) {
+      previous.draft = {
+        ...previous.draft,
+        url: step.url,
+        postStateId: step.postStateId ?? previous.draft.postStateId,
+      };
+      previous.draftIds.push(index + 1);
+      return;
+    }
+    output.push({ draft: { ...step }, draftIds: [index + 1] });
+  });
+  return output;
+}
+
+function navigationCause(step: Extract<RecordingDraftStep, { op: "navigate" }>): NavigationCause {
+  if (step.cause) return step.cause;
+  const qualifiers = step.transitionQualifiers ?? [];
+  if (qualifiers.includes("forward_back")) return "history";
+  if (qualifiers.includes("from_address_bar")) return "user_typed";
+  return TRANSITION_CAUSES[step.transitionType ?? ""] ?? "browser";
+}
+
+function selection(values: string[], labels?: string[]): Array<{ value: string; label?: string }> {
+  return values.map((value, index) => ({
+    value,
+    ...(labels?.[index] ? { label: labels[index] } : {}),
+  }));
+}
+
+function reduceDraft(draft: RecordingDraftStep, id: number): StepV3 | null {
+  if (!shouldIncludeDraft(draft)) return null;
+  const state = draft.preStateId ?? draft.postStateId;
+  const resultState = draft.postStateId ?? draft.preStateId;
+  if (!state || !resultState) return null;
+  const common = { id, state, result: { state: resultState } };
+
+  switch (draft.op) {
+    case "navigate":
+      return { op: "navigate", ...common, to: draft.url, cause: navigationCause(draft) };
+    case "click":
+      return {
+        op: "click",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+      };
+    case "hover":
+      return {
+        op: "hover",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+      };
+    case "fill":
+      return {
+        op: "fill",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+        value: draft.value,
+        commit: draft.commit ?? "blur",
+        ...(draft.redacted ? { redacted: true } : {}),
+      };
+    case "press":
+      return {
+        op: "press",
+        ...common,
+        key: draft.key,
+        ...(draft.captureTarget || draft.matchedTarget
+          ? { target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget) }
+          : {}),
+        ...(draft.modifiers?.length ? { modifiers: draft.modifiers } : {}),
+      };
+    case "select":
+      return {
+        op: "select",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+        selection: selection(draft.values, draft.labels),
+      };
+    case "scroll":
+      return { op: "scroll", ...common };
+  }
+}
+
+export interface ReducedTraceV3 {
+  steps: StepV3[];
+  stepIdByDraftId: Map<number, number>;
+}
+
+export function reduceTraceStepsV3(steps: RecordingDraftStep[]): ReducedTraceV3 {
+  const output: StepV3[] = [];
+  const stepIdByDraftId = new Map<number, number>();
+  for (const { draft, draftIds } of collapseRedirects(steps)) {
+    const step = reduceDraft(draft, output.length + 1);
+    if (!step) continue;
+    output.push(step);
+    for (const draftId of draftIds) stepIdByDraftId.set(draftId, step.id);
+  }
+  return { steps: output, stepIdByDraftId };
+}

apps/extension/src/lib/recording/trace-state-body.ts

@@ -0,0 +1,39 @@
+import type { StepAnnotation } from "./types";
+
+function annotationText(annotation: StepAnnotation, stepId: number): string {
+  return ` ⟵ step ${stepId}: ${annotation.op}${annotation.detail ? `: ${annotation.detail}` : ""}`;
+}
+
+export function formatTraceStateBody(input: {
+  stateId: string;
+  url: string;
+  title?: string;
+  stepIds: number[];
+  vomText: string;
+  annotations: StepAnnotation[];
+  stepIdByDraftId: Map<number, number>;
+}): string {
+  const lines = ["# bsk-observation 1", `state: ${JSON.stringify(input.stateId)}`];
+  lines.push(`url: ${JSON.stringify(input.url)}`);
+  if (input.title) lines.push(`title: ${JSON.stringify(input.title)}`);
+  if (input.stepIds.length > 0) lines.push(`steps_here: [${input.stepIds.join(", ")}]`);
+  lines.push("---");
+
+  const byLine = new Map<number, Array<{ annotation: StepAnnotation; stepId: number }>>();
+  for (const annotation of input.annotations) {
+    const stepId = input.stepIdByDraftId.get(annotation.draftId);
+    if (stepId === undefined) continue;
+    const bucket = byLine.get(annotation.line) ?? [];
+    bucket.push({ annotation, stepId });
+    byLine.set(annotation.line, bucket);
+  }
+
+  input.vomText.split("\n").forEach((bodyLine, lineIndex) => {
+    let line = bodyLine;
+    for (const item of byLine.get(lineIndex) ?? []) {
+      line += annotationText(item.annotation, item.stepId);
+    }
+    lines.push(line);
+  });
+  return `${lines.join("\n")}\n`;
+}

apps/extension/src/lib/recording/types.ts

@@ -0,0 +1,83 @@
+import type { CaptureTargetDescriptor } from "@/lib/describe-target";
+import type {
+  FillCommit,
+  KeyModifier,
+  NavigationCause,
+  StepV3,
+  TargetDescriptorV3,
+} from "@/transport/types";
+
+export interface TargetGeometry {
+  /** Top-level viewport-relative CSS pixels, as defined by the geometry module. */
+  rect: { x: number; y: number; w: number; h: number };
+  tag: string;
+}
+
+export interface TargetMatchHint {
+  geometry?: TargetGeometry;
+  /** Missing means the current top frame, never an unrestricted frame search. */
+  frameId?: string;
+}
+
+export interface StepAnnotation {
+  draftId: number;
+  op: StepV3["op"];
+  line: number;
+  stateId: string;
+  detail?: string;
+}
+
+interface DraftStateLink {
+  pageUrl?: string;
+  preStateId?: string;
+  postStateId?: string;
+}
+
+interface DraftTarget {
+  captureTarget?: CaptureTargetDescriptor;
+  targetHint?: TargetMatchHint;
+  matchedTarget?: TargetDescriptorV3;
+}
+
+interface DraftNavigationEffect {
+  navigatedTo?: string;
+}
+
+export type RecordingDraftStep =
+  | ({ op: "click" } & DraftStateLink & DraftTarget & DraftNavigationEffect)
+  | ({ op: "hover" } & DraftStateLink & DraftTarget)
+  | ({
+      op: "fill";
+      value: string;
+      commit?: FillCommit;
+      redacted?: boolean;
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({
+      op: "press";
+      key: string;
+      modifiers?: KeyModifier[];
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({
+      op: "select";
+      values: string[];
+      labels?: string[];
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({ op: "scroll" } & DraftStateLink)
+  | ({
+      op: "navigate";
+      url: string;
+      cause?: NavigationCause;
+      transitionType?: string;
+      transitionQualifiers?: string[];
+    } & DraftStateLink);
+
+export type TargetedRecordingDraft = Extract<
+  RecordingDraftStep,
+  { op: "click" | "hover" | "fill" | "press" | "select" }
+>;

apps/extension/src/session-manager/__tests__/ref-store.test.ts

@@ -33,4 +33,19 @@ describe("RefStore", () => {
     expect(s.resolve("@e11")).toBe(11);
     expect(s.size()).toBe(2);
   });
+
+  it("preserves the child CDP session as part of ref identity", () => {
+    const s = new RefStore();
+    s.set("e1", 42, {
+      tabId: 7,
+      frameId: "child-frame",
+      cdpSessionId: "child-session",
+    });
+    expect(s.resolveEntry("e1")).toMatchObject({
+      backendNodeId: 42,
+      tabId: 7,
+      frameId: "child-frame",
+      cdpSessionId: "child-session",
+    });
+  });
 });

apps/extension/src/session-manager/ref-store.ts

@@ -1,9 +1,10 @@
 /**
- * Per-session map from `@e<N>` snapshot refs to CDP `backendNodeId`.
+ * Per-session map from `@e<N>` snapshot refs to a CDP node address.
  *
  * Each fresh `tool.snapshot` resets the store: M6 will call
- * `replace(...)` with the new ref → backendNodeId pairs. Tools like
- * `tool.click` consume the store via `resolve("@e1")`.
+ * `replace(...)` with the new ref → node address pairs. A node address
+ * includes the owning flat CDP session/frame when the element lives in
+ * an OOPIF; tools resolve live geometry from that identity at call time.
  *
  * Refs are session-scoped (§7): looking up a ref in the wrong session
  * returns `null`, never silently leaks. Storing values in different
@@ -15,10 +16,19 @@ export type BackendNodeId = number;
 export interface RefEntry {
   backendNodeId: BackendNodeId;
   tabId: number | null;
+  frameId?: string;
+  cdpSessionId?: string;
   generation: number;
 }
 
-type RefInput = BackendNodeId | { backendNodeId: BackendNodeId; tabId: number };
+export type RefInput =
+  | BackendNodeId
+  | {
+      backendNodeId: BackendNodeId;
+      tabId: number;
+      frameId?: string;
+      cdpSessionId?: string;
+    };
 
 export class RefStore {
   private readonly map = new Map<string, RefEntry>();
@@ -44,7 +54,7 @@ export class RefStore {
   }
 
   /**
-   * Replace the entire store with a new ref → backendNodeId mapping.
+   * Replace the entire store with a new ref → CDP node identity mapping.
    * Used after every fresh `tool.snapshot`.
    */
   replace(entries: Iterable<readonly [string, RefInput]>): void {
@@ -53,10 +63,20 @@ export class RefStore {
     for (const [ref, input] of entries) this.map.set(normaliseRef(ref), this.entry(input));
   }
 
-  set(ref: string, id: BackendNodeId, opts: { tabId?: number } = {}): void {
+  set(
+    ref: string,
+    id: BackendNodeId,
+    opts: {
+      tabId?: number;
+      frameId?: string;
+      cdpSessionId?: string;
+    } = {},
+  ): void {
     this.map.set(normaliseRef(ref), {
       backendNodeId: id,
       tabId: opts.tabId ?? null,
+      ...(opts.frameId ? { frameId: opts.frameId } : {}),
+      ...(opts.cdpSessionId ? { cdpSessionId: opts.cdpSessionId } : {}),
       generation: this.generation,
     });
   }
@@ -80,6 +100,8 @@ export class RefStore {
     return {
       backendNodeId: input.backendNodeId,
       tabId: input.tabId,
+      ...(input.frameId ? { frameId: input.frameId } : {}),
+      ...(input.cdpSessionId ? { cdpSessionId: input.cdpSessionId } : {}),
       generation: this.generation,
     };
   }

apps/extension/src/tools/__tests__/borrow-confirmation.test.ts

@@ -612,4 +612,14 @@ describe("isInjectableContentScriptUrl", () => {
     ).toBe(false);
     expect(isInjectableContentScriptUrl("https://chromewebstore.google.com/")).toBe(false);
   });
+
+  it("rejects the Edge Add-ons store", () => {
+    expect(
+      isInjectableContentScriptUrl(
+        "https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg",
+      ),
+    ).toBe(false);
+    // Non-store paths on the same host stay injectable.
+    expect(isInjectableContentScriptUrl("https://microsoftedge.microsoft.com/")).toBe(true);
+  });
 });

apps/extension/src/tools/__tests__/dispatcher.test.ts

@@ -203,6 +203,55 @@ describe("ToolDispatcher", () => {
     expect(sent[0]).toEqual({ id: "r-1", result: {} });
   });
 
+  it("forwards daemon cancellation into an in-flight session stop", async () => {
+    const { transport, sent, deliver } = fakeTransport();
+    const remove = vi.fn(async () => {});
+    const sessions = new SessionManager({
+      agentWindow: {
+        create: vi.fn(async () => 4242),
+        remove,
+        ensureActiveTab: vi.fn(async () => {}),
+      },
+    });
+    await sessions.start("aa11");
+    let finishDetach: () => void = () => {};
+    const detach = new Promise<void>((resolve) => {
+      finishDetach = resolve;
+    });
+    const cdp = {
+      send: vi.fn(),
+      detachSession: vi.fn(() => detach),
+      ensureNetworkCapture: vi.fn(async () => {}),
+      networkEntriesSince: vi.fn(() => ({
+        tab_id: 7,
+        entries: [],
+        next_since: 0,
+        truncated: false,
+      })),
+      setDeviceMetricsOverride: vi.fn(async () => {}),
+      clearDeviceMetricsOverride: vi.fn(async () => {}),
+      setUserAgentOverride: vi.fn(async () => {}),
+      setTouchEmulationEnabled: vi.fn(async () => {}),
+    };
+    const dispatcher = new ToolDispatcher({ transport, sessions, cdp: cdp as TestDispatcherCdp });
+    dispatcher.start();
+
+    deliver(makeRequest("tool.session_stop", { session_id: "aa11" }));
+    await vi.waitFor(() => expect(cdp.detachSession).toHaveBeenCalledWith("aa11"));
+    deliver({ id: "cancel-stop", method: "cancel", params: { rpc_id: "r-1" } });
+    await flushMicrotasks();
+    finishDetach();
+    await flushMicrotasks();
+
+    expect(sent).toContainEqual({ id: "cancel-stop", result: { cancelled: true } });
+    expect(sent).toContainEqual({
+      id: "r-1",
+      error: expect.objectContaining({ code: "cancelled" }),
+    });
+    expect(sessions.has("aa11")).toBe(true);
+    expect(remove).not.toHaveBeenCalled();
+  });
+
   it("returns not_found when stopping an unknown session", async () => {
     const { transport, sent, deliver } = fakeTransport();
     const sessions = new SessionManager({

apps/extension/src/tools/__tests__/element-geometry.test.ts

@@ -1,24 +1,54 @@
 import { describe, expect, it } from "vitest";
-import { nodeBoundingRect, quadBoundingRect } from "../element-geometry";
+import { nodeContentRegion } from "../element-geometry";
 import type { CdpRunner } from "../shared";
 
-describe("quadBoundingRect", () => {
-  it("computes axis-aligned bounds from an 8-double quad", () => {
-    expect(quadBoundingRect([10, 20, 110, 20, 110, 60, 10, 60])).toEqual({
-      x: 10,
-      y: 20,
-      width: 100,
-      height: 40,
+describe("nodeContentRegion", () => {
+  it("rejects invalid content quads before using the box model fallback", async () => {
+    const send = async (_tabId: number, method: string) => {
+      if (method === "DOM.getContentQuads") return { quads: [[0, 0, 0, 0, 0, 0, 0, 0]] };
+      if (method === "DOM.getBoxModel") {
+        return { model: { content: [5, 10, 25, 10, 25, 30, 5, 30] } };
+      }
+      throw new Error(`unexpected CDP call ${method}`);
+    };
+
+    await expect(nodeContentRegion({ send: send as CdpRunner["send"] }, 7, 555)).resolves.toEqual([
+      [
+        { x: 5, y: 10 },
+        { x: 25, y: 10 },
+        { x: 25, y: 30 },
+        { x: 5, y: 30 },
+      ],
+    ]);
+  });
+
+  it("preserves every visible content fragment", async () => {
+    const send = async () => ({
+      quads: [
+        [10, 20, 60, 20, 60, 40, 10, 40],
+        [15, 50, 90, 50, 90, 80, 15, 80],
+      ],
     });
+    const cdp: CdpRunner = {
+      send: send as CdpRunner["send"],
+    };
+
+    await expect(nodeContentRegion(cdp, 7, 555)).resolves.toEqual([
+      [
+        { x: 10, y: 20 },
+        { x: 60, y: 20 },
+        { x: 60, y: 40 },
+        { x: 10, y: 40 },
+      ],
+      [
+        { x: 15, y: 50 },
+        { x: 90, y: 50 },
+        { x: 90, y: 80 },
+        { x: 15, y: 80 },
+      ],
+    ]);
   });
 
-  it("returns null for degenerate quads", () => {
-    expect(quadBoundingRect([0, 0, 0, 0, 0, 0, 0, 0])).toBeNull();
-    expect(quadBoundingRect([1, 2, 3])).toBeNull();
-  });
-});
-
-describe("nodeBoundingRect", () => {
   it("falls back to visible descendant bounds for zero-size containers", async () => {
     const calls: Array<{ method: string; params?: object }> = [];
     const send = async (_tabId: number, method: string, params?: object) => {
@@ -38,12 +68,14 @@ describe("nodeBoundingRect", () => {
     };
     const cdp = { send: send as CdpRunner["send"] };
 
-    await expect(nodeBoundingRect(cdp, 7, 555)).resolves.toEqual({
-      x: 242,
-      y: 468,
-      width: 769,
-      height: 180,
-    });
+    await expect(nodeContentRegion(cdp, 7, 555)).resolves.toEqual([
+      [
+        { x: 242, y: 468 },
+        { x: 1011, y: 468 },
+        { x: 1011, y: 648 },
+        { x: 242, y: 648 },
+      ],
+    ]);
     expect(calls.map((c) => c.method)).toEqual([
       "DOM.getContentQuads",
       "DOM.getBoxModel",

apps/extension/src/tools/__tests__/frame-geometry.test.ts

@@ -0,0 +1,286 @@
+import { describe, expect, it, vi } from "vitest";
+import { resolveFrameProjection, resolveNodeGeometry } from "../frame-geometry";
+import {
+  clipPolygon,
+  polygonArea,
+  polygonBounds,
+  projectAndClipRegion,
+  projectUnitPoint,
+  type Quad,
+  rectPolygon,
+  regionBounds,
+} from "../geometry";
+import type { CdpRunner } from "../shared";
+
+describe("frame geometry projection", () => {
+  it("keeps region bounds separate from polygon area", () => {
+    const region = [
+      rectPolygon({ x: 0, y: 0, w: 10, h: 10 }),
+      rectPolygon({ x: 20, y: 5, w: 5, h: 5 }),
+    ];
+    expect(regionBounds(region)).toEqual({ x: 0, y: 0, width: 25, height: 10 });
+    expect(polygonArea(region[0])).toBe(100);
+  });
+
+  it("maps through the iframe content box instead of its border box", () => {
+    const contentQuad: Quad = [
+      { x: 204, y: 306 },
+      { x: 604, y: 306 },
+      { x: 604, y: 506 },
+      { x: 204, y: 506 },
+    ];
+    const projected = projectAndClipRegion(
+      [rectPolygon({ x: 10, y: 20, w: 100, h: 40 })],
+      [{ sourceViewport: { width: 200, height: 100 }, destinationQuad: contentQuad }],
+      { width: 1000, height: 800 },
+    );
+    expect(polygonBounds(projected.flat())).toEqual({ x: 224, y: 346, width: 200, height: 80 });
+  });
+
+  it("uses a projective mapping for perspective-transformed iframe quads", () => {
+    const quad: Quad = [
+      { x: 0, y: 0 },
+      { x: 200, y: 20 },
+      { x: 180, y: 140 },
+      { x: 20, y: 100 },
+    ];
+    expect(projectUnitPoint({ x: 0, y: 0 }, quad)).toEqual(quad[0]);
+    expect(projectUnitPoint({ x: 1, y: 0 }, quad)).toEqual(quad[1]);
+    expect(projectUnitPoint({ x: 1, y: 1 }, quad)).toEqual(quad[2]);
+    expect(projectUnitPoint({ x: 0, y: 1 }, quad)).toEqual(quad[3]);
+  });
+
+  it("clips against the iframe polygon rather than its bounding box", () => {
+    const frameQuad: Quad = [
+      { x: 50, y: 0 },
+      { x: 100, y: 50 },
+      { x: 50, y: 100 },
+      { x: 0, y: 50 },
+    ];
+    expect(clipPolygon(rectPolygon({ x: 0, y: 0, w: 10, h: 10 }), frameQuad)).toEqual([]);
+  });
+
+  it("does not reapply same-target frame transforms around an OOPIF", async () => {
+    const send = vi.fn(async (_tabId, method, params) => {
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 800, clientHeight: 600 } };
+      }
+      if (method === "DOM.getBoxModel") {
+        const backendNodeId = (params as { backendNodeId?: number }).backendNodeId;
+        return backendNodeId === 20
+          ? { model: { content: [110, 70, 310, 70, 310, 170, 110, 170] } }
+          : { model: { content: [100, 50, 400, 50, 400, 250, 100, 250] } };
+      }
+      throw new Error(`unexpected root command ${method}`);
+    });
+    const cdp: CdpRunner = {
+      send: send as CdpRunner["send"],
+      sendToTarget: vi.fn(async (_target, method) => {
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 200, clientHeight: 100 } };
+        }
+        throw new Error(`unexpected child command ${method}`);
+      }) as CdpRunner["sendToTarget"],
+    };
+    const projection = await resolveFrameProjection(
+      cdp,
+      {
+        rootFrameId: "main",
+        frames: [
+          { frameId: "main", target: { tabId: 4 } },
+          {
+            frameId: "same-process-parent",
+            parentFrameId: "main",
+            ownerBackendNodeId: 10,
+            target: { tabId: 4 },
+          },
+          {
+            frameId: "oopif",
+            parentFrameId: "same-process-parent",
+            ownerBackendNodeId: 20,
+            target: { tabId: 4, sessionId: "oopif-session" },
+          },
+        ],
+      },
+      "oopif",
+    );
+
+    expect(projection?.edges).toEqual([
+      {
+        sourceViewport: { width: 200, height: 100 },
+        destinationQuad: [
+          { x: 110, y: 70 },
+          { x: 310, y: 70 },
+          { x: 310, y: 170 },
+          { x: 110, y: 170 },
+        ],
+        destinationClips: [
+          [
+            { x: 100, y: 50 },
+            { x: 400, y: 50 },
+            { x: 400, y: 250 },
+            { x: 100, y: 250 },
+          ],
+        ],
+      },
+    ]);
+  });
+
+  it("clips live OOPIF geometry at every frame boundary", async () => {
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method) => {
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 800, clientHeight: 600 } };
+        }
+        if (method === "DOM.getBoxModel") {
+          return { model: { content: [100, 100, 300, 100, 300, 200, 100, 200] } };
+        }
+        throw new Error(`unexpected root command ${method}`);
+      }) as CdpRunner["send"],
+      sendToTarget: vi.fn(async (_target, method) => {
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 200, clientHeight: 100 } };
+        }
+        if (method === "DOM.getContentQuads") {
+          return { quads: [[-50, -20, 250, -20, 250, 120, -50, 120]] };
+        }
+        throw new Error(`unexpected child command ${method}`);
+      }) as CdpRunner["sendToTarget"],
+      getFrameGraph: vi.fn(async () => ({
+        rootFrameId: "main",
+        frames: [
+          { frameId: "main", target: { tabId: 4 } },
+          {
+            frameId: "child",
+            parentFrameId: "main",
+            ownerBackendNodeId: 10,
+            target: { tabId: 4, sessionId: "child-session" },
+          },
+        ],
+      })),
+    };
+
+    const geometry = await resolveNodeGeometry(cdp, 4, {
+      target: { tabId: 4, sessionId: "child-session" },
+      frameId: "child",
+      backendNodeId: 101,
+    });
+
+    expect(geometry).toMatchObject({
+      topBounds: { x: 100, y: 100, width: 200, height: 100 },
+      actionPoint: { x: 200, y: 150 },
+    });
+  });
+
+  it("reuses one frame graph while scrolling and projecting live geometry", async () => {
+    const getFrameGraph = vi.fn(async () => ({
+      rootFrameId: "main",
+      frames: [
+        { frameId: "main", target: { tabId: 4 } },
+        {
+          frameId: "child",
+          parentFrameId: "main",
+          ownerBackendNodeId: 10,
+          target: { tabId: 4, sessionId: "child-session" },
+        },
+      ],
+    }));
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method) => {
+        if (method === "DOM.scrollIntoViewIfNeeded") return {};
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 800, clientHeight: 600 } };
+        }
+        if (method === "DOM.getBoxModel") {
+          return { model: { content: [100, 100, 300, 100, 300, 200, 100, 200] } };
+        }
+        throw new Error(`unexpected root command ${method}`);
+      }) as CdpRunner["send"],
+      sendToTarget: vi.fn(async (_target, method) => {
+        if (method === "DOM.scrollIntoViewIfNeeded") return {};
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 200, clientHeight: 100 } };
+        }
+        if (method === "DOM.getContentQuads") {
+          return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] };
+        }
+        throw new Error(`unexpected child command ${method}`);
+      }) as CdpRunner["sendToTarget"],
+      getFrameGraph,
+    };
+
+    await expect(
+      resolveNodeGeometry(
+        cdp,
+        4,
+        {
+          target: { tabId: 4, sessionId: "child-session" },
+          frameId: "child",
+          backendNodeId: 101,
+        },
+        { scrollIntoView: true },
+      ),
+    ).resolves.not.toMatchObject({ code: expect.any(String) });
+    expect(getFrameGraph).toHaveBeenCalledOnce();
+  });
+
+  it("clips live geometry to same-target iframe ancestors", async () => {
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method) => {
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 800, clientHeight: 600 } };
+        }
+        if (method === "DOM.getBoxModel") {
+          return { model: { content: [100, 100, 300, 100, 300, 200, 100, 200] } };
+        }
+        if (method === "DOM.getContentQuads") {
+          return { quads: [[50, 50, 350, 50, 350, 250, 50, 250]] };
+        }
+        throw new Error(`unexpected ${method}`);
+      }) as CdpRunner["send"],
+      getFrameGraph: vi.fn(async () => ({
+        rootFrameId: "main",
+        frames: [
+          { frameId: "main", target: { tabId: 4 } },
+          {
+            frameId: "child",
+            parentFrameId: "main",
+            ownerBackendNodeId: 10,
+            target: { tabId: 4 },
+          },
+        ],
+      })),
+    };
+
+    const geometry = await resolveNodeGeometry(cdp, 4, {
+      target: { tabId: 4 },
+      frameId: "child",
+      backendNodeId: 101,
+    });
+
+    expect(geometry).toMatchObject({
+      topBounds: { x: 100, y: 100, width: 200, height: 100 },
+      actionPoint: { x: 200, y: 150 },
+    });
+  });
+
+  it("fails closed when an OOPIF frame graph is unavailable", async () => {
+    const cdp: CdpRunner = {
+      send: vi.fn(),
+      sendToTarget: vi.fn(async (_target, method) => {
+        if (method === "DOM.getContentQuads") {
+          return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] };
+        }
+        throw new Error(`unexpected ${method}`);
+      }) as CdpRunner["sendToTarget"],
+    };
+
+    await expect(
+      resolveNodeGeometry(cdp, 4, {
+        target: { tabId: 4, sessionId: "child-session" },
+        frameId: "child",
+        backendNodeId: 101,
+      }),
+    ).resolves.toMatchObject({ code: "cdp_failed" });
+  });
+});

apps/extension/src/tools/__tests__/human-loop.test.ts

@@ -1,5 +1,6 @@
 import { afterEach, describe, expect, it, vi } from "vitest";
 import { SessionManager } from "@/session-manager/manager";
+import { RefStore } from "@/session-manager/ref-store";
 import type { RequestHelpParams } from "@/transport/types";
 import { handleRequestHelp, type RequestHelpDeps, resetHelpLifecycleForTests } from "../human-loop";
 
@@ -50,11 +51,10 @@ function installHelpLifecycleChrome() {
 }
 
 function fakeManager(sessionId: string, agentWindowId: number, tabId: number) {
+  const refStore = new RefStore();
   const mgr = {
     get: (id: string) =>
-      id === sessionId
-        ? { sessionId, agentWindowId, refStore: { resolve: () => null }, borrowedTabs: new Map() }
-        : null,
+      id === sessionId ? { sessionId, agentWindowId, refStore, borrowedTabs: new Map() } : null,
     findByWindowId: (wid: number) => (wid === agentWindowId ? { sessionId } : null),
   } as unknown as SessionManager;
   return mgr;
@@ -339,26 +339,23 @@ describe("handleRequestHelp", () => {
 
     ac.abort();
     await expect(pending).resolves.toMatchObject({ code: "cancelled" });
-    expect(cdpSend).toHaveBeenCalledWith(
-      5,
-      "DOM.querySelectorAll",
-      expect.objectContaining({ selector: "[data-bsk-help]" }),
-    );
-    expect(cdpSend).toHaveBeenCalledWith(
-      6,
-      "DOM.querySelectorAll",
-      expect.objectContaining({ selector: "[data-bsk-help]" }),
+    expect(cdpSend).not.toHaveBeenCalledWith(
+      expect.anything(),
+      "DOM.removeAttribute",
+      expect.anything(),
     );
   });
 
-  it("tags ref targets via CDP and reports them matched", async () => {
+  it("resolves ref targets to explicit viewport rectangles without mutating the page", async () => {
+    const refStore = new RefStore();
+    refStore.set("e1", 42, { tabId: 5 });
     const mgr = {
       get: (id: string) =>
         id === "abcd"
           ? {
               sessionId: "abcd",
               agentWindowId: 99,
-              refStore: { resolve: () => 42 },
+              refStore,
               borrowedTabs: new Map(),
             }
           : null,
@@ -366,7 +363,17 @@ describe("handleRequestHelp", () => {
     } as unknown as SessionManager;
     const deps = baseDeps({
       cdp: {
-        send: vi.fn(async () => ({ object: { objectId: "obj-1" } })),
+        send: vi.fn(async (_tabId, method) => {
+          if (method === "DOM.getDocument") return { root: { nodeId: 1 } };
+          if (method === "DOM.scrollIntoViewIfNeeded") return {};
+          if (method === "DOM.getContentQuads") {
+            return { quads: [[10, 20, 110, 20, 110, 60, 10, 60]] };
+          }
+          if (method === "Page.getLayoutMetrics") {
+            return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+          }
+          throw new Error(`unexpected ${method}`);
+        }),
       } as unknown as RequestHelpDeps["cdp"],
     });
     const res = await handleRequestHelp(
@@ -375,14 +382,97 @@ describe("handleRequestHelp", () => {
       deps,
     );
     const sentMsg = (deps.sendToTab as ReturnType<typeof vi.fn>).mock.calls[0][1];
-    expect(sentMsg.selectors).toContain('[data-bsk-help="0"]');
+    expect(sentMsg.selectors).toEqual([]);
+    expect(sentMsg.rects).toEqual([{ top: 20, left: 10, width: 100, height: 40 }]);
     expect(res).toMatchObject({
       outcome: "continued",
       tab_id: 5,
-      resolved_targets: [{ matched: true, ref: "@e1" }],
+      resolved_targets: [
+        {
+          matched: true,
+          ref: "@e1",
+        },
+      ],
     });
   });
 
+  it("projects an OOPIF ref through its live content quad for the help overlay", async () => {
+    const mgr = {
+      get: (id: string) =>
+        id === "abcd"
+          ? {
+              sessionId: "abcd",
+              agentWindowId: 99,
+              refStore: {
+                resolveEntry: () => ({
+                  backendNodeId: 42,
+                  tabId: 5,
+                  frameId: "child",
+                  cdpSessionId: "child-session",
+                  generation: 1,
+                }),
+              },
+              borrowedTabs: new Map(),
+            }
+          : null,
+      findByWindowId: (wid: number) => (wid === 99 ? { sessionId: "abcd" } : null),
+    } as unknown as SessionManager;
+    const send = vi.fn(async (_tabId, method) => {
+      if (method === "DOM.getDocument") return { root: { nodeId: 1 } };
+      if (method === "DOM.scrollIntoViewIfNeeded") return {};
+      if (method === "DOM.getBoxModel") {
+        return { model: { content: [204, 306, 604, 306, 604, 506, 204, 506] } };
+      }
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+      }
+      throw new Error(`unexpected root ${method}`);
+    });
+    const sendToTarget = vi.fn(async (_target, method) => {
+      if (method === "DOM.scrollIntoViewIfNeeded") return {};
+      if (method === "DOM.getContentQuads") {
+        return { quads: [[10, 20, 110, 20, 110, 60, 10, 60]] };
+      }
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 200, clientHeight: 100 } };
+      }
+      throw new Error(`unexpected child ${method}`);
+    });
+    const deps = baseDeps({
+      cdp: {
+        send,
+        sendToTarget,
+        getFrameGraph: vi.fn(async () => ({
+          rootFrameId: "main",
+          frames: [
+            { frameId: "main", target: { tabId: 5 } },
+            {
+              frameId: "child",
+              parentFrameId: "main",
+              ownerBackendNodeId: 99,
+              target: { tabId: 5, sessionId: "child-session" },
+            },
+          ],
+        })),
+      } as unknown as NonNullable<RequestHelpDeps["cdp"]>,
+    });
+
+    const res = await handleRequestHelp(
+      mgr,
+      baseParams({ tab_id: 5, targets: [{ ref: "@e1" }] }),
+      deps,
+    );
+
+    const sentMsg = (deps.sendToTab as ReturnType<typeof vi.fn>).mock.calls[0][1];
+    expect(sentMsg.rects).toEqual([{ top: 346, left: 224, width: 200, height: 80 }]);
+    expect(res).toMatchObject({ resolved_targets: [{ matched: true, ref: "@e1" }] });
+    expect(sendToTarget).toHaveBeenCalledWith(
+      { tabId: 5, sessionId: "child-session" },
+      "DOM.getContentQuads",
+      { backendNodeId: 42 },
+    );
+  });
+
   it("reports ref target unmatched when ref does not resolve", async () => {
     const deps = baseDeps();
     const res = await handleRequestHelp(
@@ -398,16 +488,15 @@ describe("handleRequestHelp", () => {
   });
 
   it("reports ref target unmatched when ref is for another tab", async () => {
+    const refStore = new RefStore();
+    refStore.set("e1", 42, { tabId: 4 });
     const mgr = {
       get: (id: string) =>
         id === "abcd"
           ? {
               sessionId: "abcd",
               agentWindowId: 99,
-              refStore: {
-                resolve: (ref: string, opts: { tabId?: number }) =>
-                  ref === "e1" && opts.tabId === 4 ? 42 : null,
-              },
+              refStore,
               borrowedTabs: new Map(),
             }
           : null,

apps/extension/src/tools/__tests__/interaction.test.ts

@@ -30,6 +30,9 @@ function makeFakeCdp(handlers: Record<string, (params: unknown) => unknown>) {
   const sendImpl = async (tabId: number, method: string, params?: object) => {
     sent.push({ tabId, method, params });
     const h = handlers[method];
+    if (!h && method === "Page.getLayoutMetrics") {
+      return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+    }
     if (!h) throw new Error(`unexpected CDP call ${method}`);
     return h(params);
   };
@@ -164,6 +167,63 @@ describe("handleClick", () => {
     });
   });
 
+  it("resolves frame refs in their CDP session and dispatches input in top coordinates", async () => {
+    const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
+    const ctx = await sm.start("aa11");
+    ctx.refStore.set("e3", 1234, {
+      tabId: 4,
+      frameId: "child-frame",
+      cdpSessionId: "child-session",
+    });
+    const fake = makeFakeCdp({
+      "Input.dispatchMouseEvent": () => ({}),
+      "DOM.scrollIntoViewIfNeeded": () => ({}),
+      "DOM.getBoxModel": () => ({
+        model: { content: [204, 306, 604, 306, 604, 506, 204, 506] },
+      }),
+    });
+    fake.cdp.getFrameGraph = vi.fn(async () => ({
+      rootFrameId: "main",
+      frames: [
+        { frameId: "main", target: { tabId: 4 } },
+        {
+          frameId: "child-frame",
+          parentFrameId: "main",
+          ownerBackendNodeId: 99,
+          target: { tabId: 4, sessionId: "child-session" },
+        },
+      ],
+    }));
+    const targetCalls: Array<{ sessionId?: string; method: string }> = [];
+    fake.cdp.sendToTarget = vi.fn(async (target, method) => {
+      targetCalls.push({ sessionId: target.sessionId, method });
+      if (method === "DOM.scrollIntoViewIfNeeded") return {};
+      if (method === "DOM.getContentQuads") {
+        return { quads: [[10, 20, 110, 20, 110, 60, 10, 60]] };
+      }
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 200, clientHeight: 100 } };
+      }
+      throw new Error(`unexpected child CDP call ${method}`);
+    }) as CdpRunner["sendToTarget"];
+
+    const res = await handleClick(
+      sm,
+      { session_id: "aa11", ref: "@e3" },
+      { cdp: fake.cdp, tabsApi: fake.tabsApi },
+    );
+
+    if ("code" in res) throw new Error(`unexpected error: ${JSON.stringify(res)}`);
+    // The iframe content box starts at (204, 306) after its border and is scaled 2x.
+    expect(res).toMatchObject({ x: 324, y: 386 });
+    expect(targetCalls).toEqual([
+      { sessionId: "child-session", method: "DOM.scrollIntoViewIfNeeded" },
+      { sessionId: "child-session", method: "DOM.getContentQuads" },
+      { sessionId: "child-session", method: "Page.getLayoutMetrics" },
+    ]);
+    expect(fake.sent.filter((call) => call.method === "Input.dispatchMouseEvent")).toHaveLength(3);
+  });
+
   it("enables overlay bypass before mouse events when overlay blocks the click point", async () => {
     const order: string[] = [];
     const bypassOverlay = vi.fn(async (_tabId: number, enabled: boolean) => {

apps/extension/src/tools/__tests__/observation.test.ts

@@ -8,6 +8,7 @@ import {
   buildFrameVomScene,
   buildVomScene,
   type CdpAxNode,
+  captureVomObservation,
   handleGetHtml,
   handleObserve,
   handleScreenshot,
@@ -63,6 +64,9 @@ function makeFakeCdp(handlers: Record<string, (params?: object) => unknown>) {
   const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
     sent.push({ method, params });
     const handler = handlers[method];
+    if (!handler && method === "Page.getLayoutMetrics") {
+      return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+    }
     if (!handler) throw new Error(`unexpected CDP call ${method}`);
     return handler(params);
   });
@@ -586,6 +590,7 @@ describe("buildVomScene", () => {
         {
           frameId: "main",
           contextScopeId: "main",
+          target: { tabId: 7 },
           domNodes: mainNodes,
           axNodes: [
             axNode("root", 1, "RootWebArea"),
@@ -598,6 +603,7 @@ describe("buildVomScene", () => {
           contextScopeId: "first",
           parentFrameId: "main",
           ownerBackendNodeId: 10,
+          target: { tabId: 7, sessionId: "session-first" },
           domNodes: firstNodes,
           axNodes: [
             axNode("root", 100, "RootWebArea"),
@@ -609,6 +615,7 @@ describe("buildVomScene", () => {
           contextScopeId: "second",
           parentFrameId: "main",
           ownerBackendNodeId: 20,
+          target: { tabId: 7, sessionId: "session-second" },
           domNodes: secondNodes,
           axNodes: [
             axNode("root", 200, "RootWebArea"),
@@ -621,6 +628,7 @@ describe("buildVomScene", () => {
           contextScopeId: "nested",
           parentFrameId: "second",
           ownerBackendNodeId: 210,
+          target: { tabId: 7, sessionId: "session-nested" },
           domNodes: nestedNodes,
           axNodes: [
             axNode("root", 300, "RootWebArea"),
@@ -673,6 +681,7 @@ describe("buildVomScene", () => {
         {
           frameId: "main",
           contextScopeId: "main",
+          target: { tabId: 7 },
           domNodes: [],
           axNodes: [],
         },
@@ -680,6 +689,7 @@ describe("buildVomScene", () => {
           frameId: "child",
           contextScopeId: "child",
           parentFrameId: "main",
+          target: { tabId: 7 },
           domNodes: [childNode],
           axNodes: [
             {
@@ -740,6 +750,7 @@ describe("buildVomScene", () => {
         {
           frameId: "main",
           contextScopeId: "main",
+          target: { tabId: 7 },
           domNodes: mainNodes,
           axNodes: [
             {
@@ -761,6 +772,7 @@ describe("buildVomScene", () => {
           contextScopeId: "child",
           parentFrameId: "main",
           ownerBackendNodeId: 10,
+          target: { tabId: 7, sessionId: "child-session" },
           domNodes: [],
           axNodes: [
             {
@@ -1318,7 +1330,7 @@ describe("buildVomScene", () => {
     expect(rendered).toContain('      @e2 textbox "验证码"');
   });
 
-  it("does not mark non-password inputs sensitive from password-like labels", () => {
+  it("marks current-password autocomplete as sensitive even for text inputs", () => {
     const axNodes: CdpAxNode[] = [
       {
         nodeId: "1",
@@ -1353,7 +1365,7 @@ describe("buildVomScene", () => {
     expect(buildVomScene(axNodes, captured).nodes[0]).toEqual(
       expect.objectContaining({
         id: 10,
-        sensitive: false,
+        sensitive: true,
       }),
     );
   });
@@ -1648,7 +1660,9 @@ describe("buildVomScene", () => {
     );
     const rendered = renderVom(scene);
     expect(rendered.text).toContain('@e1 button "close"');
-    expect(rendered.refs).toEqual([{ ref: "e1", backendNodeId: 20 }]);
+    expect(rendered.refs.map(({ ref, backendNodeId }) => ({ ref, backendNodeId }))).toEqual([
+      { ref: "e1", backendNodeId: 20 },
+    ]);
   });
 
   it("does not promote a clickable container that wraps a real interactive control", () => {
@@ -1792,7 +1806,9 @@ describe("buildVomScene", () => {
     expect(scene.nodes.find((n) => n.id === 30)?.role).toBe("generic");
     const rendered = renderVom(scene);
     expect(rendered.text).toContain('@e1 button "收藏"');
-    expect(rendered.refs).toEqual([{ ref: "e1", backendNodeId: 20 }]);
+    expect(rendered.refs.map(({ ref, backendNodeId }) => ({ ref, backendNodeId }))).toEqual([
+      { ref: "e1", backendNodeId: 20 },
+    ]);
   });
 
   it("builds active scope blocks from active aria-controls relationships", () => {
@@ -2893,10 +2909,360 @@ describe("handleSnapshot", () => {
       ],
     };
   }
+
+  function secretsSnapshotReply(secrets: {
+    email: string;
+    password: string;
+    otp: string;
+    card: string;
+  }) {
+    const S = [
+      "html",
+      "body",
+      "input",
+      "position",
+      "static",
+      "pointer-events",
+      "auto",
+      "type",
+      "text",
+      "password",
+      "autocomplete",
+      "one-time-code",
+      "cc-number",
+      "value",
+      secrets.email,
+      secrets.password,
+      secrets.otp,
+      secrets.card,
+    ];
+    const i = (s: string) => S.indexOf(s);
+    const style = [i("static"), i("auto"), i("auto")];
+    return {
+      strings: S,
+      documents: [
+        {
+          nodes: {
+            parentIndex: [-1, 0, 1, 1, 1, 1],
+            nodeName: [i("html"), i("body"), i("input"), i("input"), i("input"), i("input")],
+            backendNodeId: [10, 11, 12, 13, 14, 15],
+            attributes: [
+              [],
+              [],
+              [i("type"), i("text"), i("value"), i(secrets.email)],
+              [i("type"), i("password"), i("value"), i(secrets.password)],
+              [
+                i("type"),
+                i("text"),
+                i("autocomplete"),
+                i("one-time-code"),
+                i("value"),
+                i(secrets.otp),
+              ],
+              [
+                i("type"),
+                i("text"),
+                i("autocomplete"),
+                i("cc-number"),
+                i("value"),
+                i(secrets.card),
+              ],
+            ],
+            inputValue: {
+              index: [2, 3, 4, 5],
+              value: [i(secrets.email), i(secrets.password), i(secrets.otp), i(secrets.card)],
+            },
+          },
+          layout: {
+            nodeIndex: [1, 2, 3, 4, 5],
+            styles: [style, style, style, style, style],
+            bounds: [
+              [0, 0, 1000, 800],
+              [10, 10, 200, 32],
+              [10, 50, 200, 32],
+              [10, 90, 200, 32],
+              [10, 130, 200, 32],
+            ],
+            paintOrders: [0, 1, 2, 3, 4],
+          },
+        },
+      ],
+    };
+  }
+
   const VP_METRICS = {
     cssLayoutViewport: { clientWidth: 1000, clientHeight: 800, pageX: 0, pageY: 0 },
   };
 
+  function makeFrameAwareDeps() {
+    const strings = ["html", "body", "iframe", "button", "title", "Remote", "static", "auto"];
+    const i = (value: string) => strings.indexOf(value);
+    const styles = [i("static"), i("auto"), i("auto")];
+    const snapshot = {
+      strings,
+      documents: [
+        {
+          frameId: "main",
+          nodes: {
+            parentIndex: [-1, 0, 1],
+            nodeName: [i("html"), i("body"), i("iframe")],
+            backendNodeId: [10, 11, 12],
+            attributes: [[], [], [i("title"), i("Remote")]],
+            contentDocumentIndex: { index: [2], value: [1] },
+          },
+          layout: {
+            nodeIndex: [0, 1, 2],
+            styles: [styles, styles, styles],
+            bounds: [
+              [0, 0, 1000, 800],
+              [0, 0, 1000, 800],
+              [100, 100, 400, 300],
+            ],
+            paintOrders: [0, 0, 1],
+          },
+        },
+        {
+          frameId: "child",
+          nodes: {
+            parentIndex: [-1, 0, 1],
+            nodeName: [i("html"), i("body"), i("button")],
+            backendNodeId: [20, 21, 22],
+            attributes: [[], [], []],
+          },
+          layout: {
+            nodeIndex: [0, 1, 2],
+            styles: [styles, styles, styles],
+            bounds: [
+              [0, 0, 400, 300],
+              [0, 0, 400, 300],
+              [20, 30, 120, 40],
+            ],
+            paintOrders: [0, 0, 1],
+          },
+        },
+      ],
+    };
+    const mainAx: CdpAxNode[] = [
+      {
+        nodeId: "main-root",
+        role: { type: "role", value: "RootWebArea" },
+        backendDOMNodeId: 11,
+        childIds: ["frame-owner"],
+      },
+      {
+        nodeId: "frame-owner",
+        parentId: "main-root",
+        role: { type: "role", value: "Iframe" },
+        name: { type: "computedString", value: "Remote" },
+        backendDOMNodeId: 12,
+      },
+    ];
+    const childAx: CdpAxNode[] = [
+      {
+        nodeId: "child-root",
+        role: { type: "role", value: "RootWebArea" },
+        backendDOMNodeId: 21,
+        childIds: ["child-button"],
+      },
+      {
+        nodeId: "child-button",
+        parentId: "child-root",
+        role: { type: "role", value: "button" },
+        name: { type: "computedString", value: "Frame action" },
+        backendDOMNodeId: 22,
+      },
+    ];
+    const send = vi.fn(async (_tabId: number, method: string) => {
+      if (method === "Page.getLayoutMetrics") return VP_METRICS;
+      if (method === "DOMSnapshot.enable" || method === "Accessibility.enable") return {};
+      if (method === "DOMSnapshot.captureSnapshot") return snapshot;
+      if (method === "Accessibility.getFullAXTree") return { nodes: mainAx };
+      throw new Error(`unexpected root CDP method ${method}`);
+    });
+    const sendToTarget = vi.fn(async (_target, method: string) => {
+      if (method === "Accessibility.enable") return {};
+      if (method === "Accessibility.getFullAXTree") return { nodes: childAx };
+      throw new Error(`unexpected child CDP method ${method}`);
+    });
+    const cdp = {
+      send: send as unknown as CdpRunner["send"],
+      sendToTarget: sendToTarget as unknown as NonNullable<CdpRunner["sendToTarget"]>,
+      getFrameGraph: vi.fn(async () => ({
+        rootFrameId: "main",
+        frames: [
+          { frameId: "main", target: { tabId: 4 } },
+          {
+            frameId: "child",
+            parentFrameId: "main",
+            ownerBackendNodeId: 12,
+            target: { tabId: 4, sessionId: "child-session" },
+          },
+        ],
+      })),
+      trackSessionTab: vi.fn(),
+    } satisfies CdpRunner;
+    return {
+      cdp,
+      tabsApi: {
+        get: vi.fn(
+          async (tabId: number) => ({ id: tabId, windowId: 100, active: true }) as chrome.tabs.Tab,
+        ),
+        query: vi.fn(async () => [{ id: 4, windowId: 100, active: true } as chrome.tabs.Tab]),
+      },
+    };
+  }
+
+  it("exposes the frame-aware observation result for recording", async () => {
+    const ax: CdpAxNode[] = [
+      {
+        nodeId: "root",
+        role: { type: "role", value: "RootWebArea" },
+        backendDOMNodeId: 11,
+        childIds: ["password"],
+      },
+      {
+        nodeId: "password",
+        parentId: "root",
+        role: { type: "role", value: "textbox" },
+        name: { type: "computedString", value: "Password" },
+        value: { value: "hunter2" },
+        backendDOMNodeId: 13,
+      },
+    ];
+    const deps = makeOverlayDeps(ax, loginSnapshotReply(), VP_METRICS);
+
+    const result = await captureVomObservation(deps.cdp, 4, "https://example.com", {
+      redactValues: true,
+    });
+
+    expect(result.text).not.toContain("hunter2");
+    expect(result.text).toContain("•••");
+    expect(result.refs[0]).toMatchObject({
+      backendNodeId: 13,
+      role: "textbox",
+      name: "Password",
+      line: expect.any(Number),
+    });
+    expect(result.rootFrameId).toBe("root");
+    expect(result).not.toHaveProperty("frameDocuments");
+    expect(result.frames).toEqual([{ frameId: "root", target: { tabId: 4 } }]);
+    expect(result.matchNodes.find((node) => node.backendNodeId === 13)).toMatchObject({
+      frameId: "root",
+      backendNodeId: 13,
+      tag: "input",
+      rect: { x: 400, y: 300, w: 200, h: 40 },
+      localRect: { x: 400, y: 300, w: 200, h: 40 },
+    });
+  });
+
+  it("does not leak form secrets through the record-safe observation payload", async () => {
+    const secrets = {
+      email: "user@example.com",
+      password: "hunter2",
+      otp: "847291",
+      card: "4111111111111111",
+    };
+    const ax: CdpAxNode[] = [
+      {
+        nodeId: "root",
+        role: { type: "role", value: "RootWebArea" },
+        backendDOMNodeId: 11,
+        childIds: ["email", "password", "otp", "card"],
+      },
+      {
+        nodeId: "email",
+        parentId: "root",
+        role: { type: "role", value: "textbox" },
+        name: { type: "computedString", value: "Email" },
+        value: { value: secrets.email },
+        backendDOMNodeId: 12,
+      },
+      {
+        nodeId: "password",
+        parentId: "root",
+        role: { type: "role", value: "textbox" },
+        name: { type: "computedString", value: "Password" },
+        value: { value: secrets.password },
+        backendDOMNodeId: 13,
+      },
+      {
+        nodeId: "otp",
+        parentId: "root",
+        role: { type: "role", value: "textbox" },
+        name: { type: "computedString", value: "Code" },
+        value: { value: secrets.otp },
+        backendDOMNodeId: 14,
+      },
+      {
+        nodeId: "card",
+        parentId: "root",
+        role: { type: "role", value: "textbox" },
+        name: { type: "computedString", value: "Card" },
+        value: { value: secrets.card },
+        backendDOMNodeId: 15,
+      },
+    ];
+    const deps = makeOverlayDeps(ax, secretsSnapshotReply(secrets), VP_METRICS);
+
+    const result = await captureVomObservation(deps.cdp, 4, "https://example.com", {
+      redactValues: true,
+    });
+    const dumped = JSON.stringify(result);
+
+    expect(result).not.toHaveProperty("frameDocuments");
+    expect(dumped).not.toContain(secrets.email);
+    expect(dumped).not.toContain(secrets.password);
+    expect(dumped).not.toContain(secrets.otp);
+    expect(dumped).not.toContain(secrets.card);
+    expect(dumped).not.toContain("formValue");
+    expect(dumped).not.toContain("formDefaultValue");
+    expect(dumped).not.toContain("axNodes");
+    expect(dumped).not.toContain("domNodes");
+    expect(dumped).not.toContain("attrs");
+    expect(result.text).toContain("•••");
+  });
+
+  it("keeps frames and rendered refs on the same frame identity", async () => {
+    const deps = makeFrameAwareDeps();
+
+    const result = await captureVomObservation(deps.cdp, 4, "https://example.com");
+
+    expect(result.rootFrameId).toBe("main");
+    expect(result.frames).toHaveLength(2);
+    expect(result.frames.find((frame) => frame.frameId === "child")).toEqual({
+      frameId: "child",
+      parentFrameId: "main",
+      ownerBackendNodeId: 12,
+      target: { tabId: 4, sessionId: "child-session" },
+    });
+    expect(result.matchNodes.find((node) => node.backendNodeId === 22)).toMatchObject({
+      frameId: "child",
+      tag: "button",
+      localRect: { x: 20, y: 30, w: 120, h: 40 },
+    });
+    expect(result.refs.find((ref) => ref.backendNodeId === 22)).toMatchObject({
+      frameId: "child",
+      name: "Frame action",
+    });
+  });
+
+  it("stores iframe refs with their owning CDP session", async () => {
+    const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
+    const ctx = await sm.start("aa11");
+    const deps = makeFrameAwareDeps();
+
+    const result = await handleSnapshot(sm, { session_id: "aa11" }, deps);
+
+    if ("code" in result) throw new Error(`unexpected error: ${JSON.stringify(result)}`);
+    expect(result.text).toContain('@e1 button "Frame action"');
+    const frameRef = [...ctx.refStore.entries()].find(([, entry]) => entry.backendNodeId === 22);
+    expect(frameRef?.[1]).toMatchObject({
+      tabId: 4,
+      frameId: "child",
+      cdpSessionId: "child-session",
+    });
+  });
+
   it("renders a blocking login overlay as the focused top layer", async () => {
     const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
     await sm.start("aa11");
@@ -3407,6 +3773,32 @@ describe("handleGetHtml", () => {
     expect(deps.send).toHaveBeenCalledTimes(1);
   });
 
+  it("reads a frame ref through its child CDP session", async () => {
+    const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
+    const ctx = await sm.start("aa11");
+    ctx.refStore.set("e7", 4242, {
+      tabId: 4,
+      frameId: "child-frame",
+      cdpSessionId: "child-session",
+    });
+    const deps = makeDeps({});
+    const sendToTarget = vi.fn(async (target, method, params) => {
+      expect(target).toEqual({ tabId: 4, sessionId: "child-session" });
+      expect(method).toBe("DOM.getOuterHTML");
+      expect(params).toEqual({ backendNodeId: 4242 });
+      return { outerHTML: "<button>frame</button>" };
+    });
+    (deps.cdp as CdpRunner).sendToTarget = sendToTarget as unknown as NonNullable<
+      CdpRunner["sendToTarget"]
+    >;
+
+    const res = await handleGetHtml(sm, { session_id: "aa11", ref: "@e7" }, deps);
+
+    if ("code" in res) throw new Error(`unexpected error: ${JSON.stringify(res)}`);
+    expect(res.html).toBe("<button>frame</button>");
+    expect(deps.send).not.toHaveBeenCalled();
+  });
+
   it("returns not_found when a ref belongs to another tab", async () => {
     const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
     const ctx = await sm.start("aa11");

apps/extension/src/tools/__tests__/session.test.ts

@@ -66,6 +66,52 @@ function makeApis(
 }
 
 describe("handleSessionStop with auto-return", () => {
+  it("leaves the session untouched when cancellation arrived before teardown", async () => {
+    const aw = fakeAgentWindow([100]);
+    const sm = new SessionManager({ agentWindow: aw });
+    await sm.start("aa11");
+    const cdp = { detachSession: vi.fn(async () => {}) };
+    const controller = new AbortController();
+    controller.abort();
+
+    const res = await handleSessionStop(
+      sm,
+      { session_id: "aa11" },
+      { cdp, signal: controller.signal },
+    );
+
+    expect(res).toMatchObject({ code: "cancelled" });
+    expect(sm.has("aa11")).toBe(true);
+    expect(cdp.detachSession).not.toHaveBeenCalled();
+    expect(aw.remove).not.toHaveBeenCalled();
+  });
+
+  it("does not close the Agent Window when cancellation lands during CDP detach", async () => {
+    const aw = fakeAgentWindow([100]);
+    const sm = new SessionManager({ agentWindow: aw });
+    await sm.start("aa11");
+    const controller = new AbortController();
+    let finishDetach: () => void = () => {};
+    const detach = new Promise<void>((resolve) => {
+      finishDetach = resolve;
+    });
+    const cdp = { detachSession: vi.fn(() => detach) };
+
+    const stopping = handleSessionStop(
+      sm,
+      { session_id: "aa11" },
+      { cdp, signal: controller.signal },
+    );
+    await vi.waitFor(() => expect(cdp.detachSession).toHaveBeenCalledWith("aa11"));
+    controller.abort();
+    finishDetach();
+
+    const res = await stopping;
+    expect(res).toMatchObject({ code: "cancelled" });
+    expect(sm.has("aa11")).toBe(true);
+    expect(aw.remove).not.toHaveBeenCalled();
+  });
+
   it("returns every borrowed tab and closes the Agent Window in the right order", async () => {
     const aw = fakeAgentWindow([100]);
     const sm = new SessionManager({ agentWindow: aw });

apps/extension/src/tools/__tests__/snapshot-ref.test.ts

@@ -46,6 +46,25 @@ describe("lookupSnapshotRef", () => {
 });
 
 describe("resolveSnapshotRef", () => {
+  it("preserves the frame and child session needed to route iframe refs", async () => {
+    const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
+    const ctx = await sm.start("aa11");
+    ctx.refStore.set("e3", 1234, {
+      tabId: 4,
+      frameId: "child-frame",
+      cdpSessionId: "child-session",
+    });
+
+    const expected = {
+      backendNodeId: 1234,
+      refKey: "e3",
+      frameId: "child-frame",
+      cdpSessionId: "child-session",
+    };
+    expect(lookupSnapshotRef(ctx, "@e3", 4)).toEqual(expected);
+    expect(resolveSnapshotRef(ctx, "@e3", 4)).toEqual(expected);
+  });
+
   it("returns not_found for unknown ref", async () => {
     const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
     const ctx = await sm.start("aa11");

apps/extension/src/tools/borrow-confirmation.ts

@@ -250,9 +250,10 @@ const DEFAULT_NOTIFICATION_COPY: BorrowNotificationCopy = {
 // URL injection-eligibility test
 // ---------------------------------------------------------------------------
 
-const CHROME_WEB_STORE_RES = [
+const EXTENSION_STORE_RES = [
   /^https:\/\/chrome\.google\.com\/webstore/i,
   /^https:\/\/chromewebstore\.google\.com/i,
+  /^https:\/\/microsoftedge\.microsoft\.com\/addons/i,
 ];
 
 /**
@@ -264,14 +265,15 @@ const CHROME_WEB_STORE_RES = [
  *   - `ftp://` no longer hosts content scripts reliably in modern Chrome.
  *   - `about:` / `chrome:` / `chrome-extension:` / `edge:` / `devtools:` /
  *     `view-source:` / `data:` / `blob:` are blocked by the platform.
- *   - The Chrome Web Store (both legacy and new domains) is also blocked.
+ *   - Extension storefronts are blocked by their own browser: the Chrome Web
+ *     Store (legacy and new domains) under Chrome, and Edge Add-ons under Edge.
  *
  * Mirrors the implicit scheme list documented in
  * https://developer.chrome.com/docs/extensions/develop/concepts/match-patterns.
  */
 export function isInjectableContentScriptUrl(url: string | undefined): boolean {
   if (!url) return false;
-  for (const re of CHROME_WEB_STORE_RES) {
+  for (const re of EXTENSION_STORE_RES) {
     if (re.test(url)) return false;
   }
   return /^https?:\/\//i.test(url);

apps/extension/src/tools/capture-vom-observation.ts

@@ -0,0 +1,9 @@
+export {
+  type CaptureVomObservationOptions,
+  captureVomObservation,
+} from "./observation";
+export {
+  type CaptureVomFrame,
+  type CaptureVomMatchNode,
+  type CaptureVomObservationResult,
+} from "./vom/record-safe-observation";

apps/extension/src/tools/dispatcher.ts

@@ -290,6 +290,7 @@ export class ToolDispatcher {
         await this.releaseHoverLatch((req.params as SessionStopParams).session_id);
         return handleSessionStop(this.sessions, req.params as SessionStopParams, {
           cdp: this.cdp,
+          signal,
         });
       }
       case "tool.tab_list":

apps/extension/src/tools/element-geometry.ts

@@ -1,9 +1,15 @@
-// Shared CDP helpers for scrolling nodes into view and computing
-// viewport-space bounding rectangles. Used by interaction tools (click
-// centre) and observation tools (element screenshot clip).
+// Resolve and scroll nodes inside one CDP target. Cross-frame projection
+// belongs to frame-geometry.ts.
 
 import type { RpcError } from "@/transport/types";
 import { rpcError } from "./errors";
+import {
+  parseCdpQuad,
+  polygonBounds,
+  type Region,
+  rectPolygon,
+  type ViewportRect,
+} from "./geometry";
 import { type CdpRunner, isRpcError } from "./shared";
 
 const ELEMENT_NOT_VISIBLE_MESSAGE =
@@ -13,45 +19,6 @@ function elementNotVisibleError(): RpcError {
   return rpcError("permission_denied", "element_not_visible", ELEMENT_NOT_VISIBLE_MESSAGE);
 }
 
-/** Viewport-space axis-aligned bounding box for CDP `Page.captureScreenshot` clip. */
-export interface ViewportRect {
-  x: number;
-  y: number;
-  width: number;
-  height: number;
-}
-
-/**
- * Compute the axis-aligned bounding box of an 8-double CDP content
- * quad / box-model polygon. Exported for unit tests.
- */
-export function quadBoundingRect(quad: number[]): ViewportRect | null {
-  if (quad.length !== 8) return null;
-  const xs = [quad[0], quad[2], quad[4], quad[6]];
-  const ys = [quad[1], quad[3], quad[5], quad[7]];
-  const minX = Math.min(...xs);
-  const maxX = Math.max(...xs);
-  const minY = Math.min(...ys);
-  const maxY = Math.max(...ys);
-  const width = maxX - minX;
-  const height = maxY - minY;
-  if (width <= 0 || height <= 0) return null;
-  return { x: minX, y: minY, width, height };
-}
-
-function rectToQuad(rect: ViewportRect): number[] {
-  return [
-    rect.x,
-    rect.y,
-    rect.x + rect.width,
-    rect.y,
-    rect.x + rect.width,
-    rect.y + rect.height,
-    rect.x,
-    rect.y + rect.height,
-  ];
-}
-
 /**
  * Resolve `backendNodeId` → CDP `objectId` so we can invoke
  * `Runtime.callFunctionOn` against the live JS object.
@@ -112,48 +79,24 @@ export async function scrollNodeIntoView(
   }
 }
 
-/**
- * Viewport-space bounding box for `backendNodeId`. Prefers
- * `DOM.getContentQuads`, then `DOM.getBoxModel`, then the union of
- * visible descendant client rects for zero-size overflow containers.
- */
-export async function nodeBoundingRect(
+function validCdpRegion(quads: number[][] | undefined): Region {
+  return (quads ?? []).flatMap((raw) => {
+    const polygon = parseCdpQuad(raw);
+    return polygon && polygonBounds(polygon) ? [polygon] : [];
+  });
+}
+
+async function resolveVisibleContentRegion(
   cdp: CdpRunner,
   tabId: number,
   backendNodeId: number,
-): Promise<ViewportRect | RpcError> {
-  const polygon = await visibleContentPolygon(cdp, tabId, backendNodeId);
-  if (isRpcError(polygon)) return polygon;
-  // visibleContentPolygon only returns quads with positive area.
-  return quadBoundingRect(polygon)!;
-}
-
-/**
- * Compute the centroid of a CDP content quad. Quads are reported as
- * 8 doubles in clockwise order: (x1, y1, x2, y2, x3, y3, x4, y4).
- */
-export function quadCentre(quad: number[]): { x: number; y: number } {
-  const x = (quad[0] + quad[4]) / 2;
-  const y = (quad[1] + quad[5]) / 2;
-  return { x, y };
-}
-
-/** Centre of a `DOM.getBoxModel` `content` polygon (also 8 doubles). */
-export function boxCentre(box: number[]): { x: number; y: number } {
-  return quadCentre(box);
-}
-
-async function visibleContentPolygon(
-  cdp: CdpRunner,
-  tabId: number,
-  backendNodeId: number,
-): Promise<number[] | RpcError> {
+): Promise<Region | RpcError> {
   try {
     const quads = await cdp.send<{ quads?: number[][] }>(tabId, "DOM.getContentQuads", {
       backendNodeId,
     });
-    const quad = quads.quads?.find((q) => q.length === 8 && quadBoundingRect(q) !== null);
-    if (quad) return quad;
+    const visible = validCdpRegion(quads.quads);
+    if (visible.length > 0) return visible;
   } catch (err) {
     console.debug("[bsk element-geometry] getContentQuads failed", err);
   }
@@ -162,15 +105,34 @@ async function visibleContentPolygon(
       backendNodeId,
     });
     const content = box.model?.content;
-    if (content && content.length === 8 && quadBoundingRect(content)) return content;
+    const fallback = validCdpRegion(content ? [content] : undefined);
+    if (fallback.length > 0) return fallback;
   } catch (err) {
     console.debug("[bsk element-geometry] getBoxModel failed", err);
   }
   const descendantRect = await descendantBoundingRect(cdp, tabId, backendNodeId);
-  if (descendantRect) return rectToQuad(descendantRect);
+  if (descendantRect) {
+    return [
+      rectPolygon({
+        x: descendantRect.x,
+        y: descendantRect.y,
+        w: descendantRect.width,
+        h: descendantRect.height,
+      }),
+    ];
+  }
   return elementNotVisibleError();
 }
 
+/** Resolve every visible content region in the node's target-local viewport. */
+export async function nodeContentRegion(
+  cdp: CdpRunner,
+  tabId: number,
+  backendNodeId: number,
+): Promise<Region | RpcError> {
+  return resolveVisibleContentRegion(cdp, tabId, backendNodeId);
+}
+
 async function descendantBoundingRect(
   cdp: CdpRunner,
   tabId: number,
@@ -241,20 +203,3 @@ function parseViewportRect(value: unknown): ViewportRect | null {
   if (![x, y, width, height].every(Number.isFinite) || width <= 0 || height <= 0) return null;
   return { x, y, width, height };
 }
-
-/**
- * Get the click point for `backendNodeId`. Prefers
- * `DOM.getContentQuads` (richer for rotated / transformed elements);
- * falls back to `DOM.getBoxModel`, then visible descendant bounds.
- * Returns `permission_denied` with "element not visible" when every
- * geometry path comes back empty / fails.
- */
-export async function nodeCentre(
-  cdp: CdpRunner,
-  tabId: number,
-  backendNodeId: number,
-): Promise<{ x: number; y: number } | RpcError> {
-  const polygon = await visibleContentPolygon(cdp, tabId, backendNodeId);
-  if (isRpcError(polygon)) return polygon;
-  return quadCentre(polygon);
-}

apps/extension/src/tools/frame-geometry.ts

@@ -0,0 +1,290 @@
+import { type CdpFrame, type CdpFrameGraph, type CdpTarget } from "@/browser-driver/frame-graph";
+import type { RpcError } from "@/transport/types";
+import { nodeContentRegion, scrollNodeIntoView } from "./element-geometry";
+import {
+  clipPolygon,
+  type GeometryProjection,
+  type Point,
+  type Polygon,
+  type ProjectiveEdge,
+  parseCdpQuad,
+  polygonArea,
+  polygonCentroid,
+  projectRegionToViewport,
+  type Quad,
+  type Region,
+  rectPolygon,
+  regionBounds,
+  type Size,
+  type ViewportRect,
+} from "./geometry";
+import { type CdpRunner, cdpRunnerForTarget, isRpcError, sendToCdpTarget } from "./shared";
+
+export interface NodeAddress {
+  target: CdpTarget;
+  backendNodeId: number;
+  frameId?: string;
+}
+
+export interface ResolvedNodeGeometry {
+  topVisibleRegions: Region;
+  topBounds: ViewportRect;
+  actionPoint: Point;
+}
+
+function geometryError(message: string): RpcError {
+  return { code: "cdp_failed", message };
+}
+
+function frameMap(graph: CdpFrameGraph): Map<string, CdpFrame> {
+  return new Map(graph.frames.map((frame) => [frame.frameId, frame]));
+}
+
+function targetRootFrame(byId: Map<string, CdpFrame>, frame: CdpFrame): CdpFrame | null {
+  const seen = new Set<string>();
+  let current = frame;
+  while (current.parentFrameId) {
+    if (seen.has(current.frameId)) return null;
+    seen.add(current.frameId);
+    const parent = byId.get(current.parentFrameId);
+    if (!parent || parent.target.sessionId !== current.target.sessionId) break;
+    current = parent;
+  }
+  return current;
+}
+
+function frameAncestry(graph: CdpFrameGraph, frameId: string): CdpFrame[] | null {
+  const byId = frameMap(graph);
+  const path: CdpFrame[] = [];
+  const seen = new Set<string>();
+  let current = byId.get(frameId);
+  if (!current) return null;
+  while (current.parentFrameId) {
+    if (seen.has(current.frameId)) return null;
+    seen.add(current.frameId);
+    path.push(current);
+    const parent = byId.get(current.parentFrameId);
+    if (!parent) return null;
+    current = parent;
+  }
+  return path;
+}
+
+async function targetViewport(cdp: CdpRunner, target: CdpTarget): Promise<Size | null> {
+  const metrics = await sendToCdpTarget<{
+    cssLayoutViewport?: { clientWidth?: number; clientHeight?: number };
+    layoutViewport?: { clientWidth?: number; clientHeight?: number };
+  }>(cdp, target, "Page.getLayoutMetrics", {});
+  const viewport = metrics.cssLayoutViewport ?? metrics.layoutViewport ?? {};
+  const width = viewport.clientWidth ?? 0;
+  const height = viewport.clientHeight ?? 0;
+  return width > 0 && height > 0 ? { width, height } : null;
+}
+
+async function ownerContentQuad(
+  cdp: CdpRunner,
+  parent: CdpFrame,
+  ownerBackendNodeId: number,
+): Promise<Quad | null> {
+  const result = await sendToCdpTarget<{ model?: { content?: number[] } }>(
+    cdp,
+    parent.target,
+    "DOM.getBoxModel",
+    { backendNodeId: ownerBackendNodeId },
+  );
+  return parseCdpQuad(result.model?.content);
+}
+
+async function sameTargetFrameClips(
+  cdp: CdpRunner,
+  byId: Map<string, CdpFrame>,
+  frame: CdpFrame,
+  targetRoot: CdpFrame,
+): Promise<Polygon[] | null> {
+  const clips: Polygon[] = [];
+  let current = frame;
+  const seen = new Set<string>();
+  while (current.frameId !== targetRoot.frameId) {
+    if (seen.has(current.frameId) || !current.parentFrameId) return null;
+    seen.add(current.frameId);
+    const parent = byId.get(current.parentFrameId);
+    if (!parent || current.ownerBackendNodeId === undefined) return null;
+    const clip = await ownerContentQuad(cdp, parent, current.ownerBackendNodeId);
+    if (!clip) return null;
+    clips.push(clip);
+    current = parent;
+  }
+  return clips;
+}
+
+export async function resolveFrameProjection(
+  cdp: CdpRunner,
+  graph: CdpFrameGraph,
+  frameId: string,
+): Promise<GeometryProjection | null> {
+  const byId = frameMap(graph);
+  const frame = byId.get(frameId);
+  if (!frame) return null;
+  let targetRoot = targetRootFrame(byId, frame);
+  if (!targetRoot) return null;
+  const sourceViewport = await targetViewport(cdp, targetRoot.target);
+  if (!sourceViewport) return null;
+  const sourceClips = await sameTargetFrameClips(cdp, byId, frame, targetRoot);
+  if (!sourceClips) return null;
+
+  const edges: ProjectiveEdge[] = [];
+  while (targetRoot.parentFrameId) {
+    const parent = byId.get(targetRoot.parentFrameId);
+    if (!parent || targetRoot.ownerBackendNodeId === undefined) return null;
+    const destinationQuad = await ownerContentQuad(cdp, parent, targetRoot.ownerBackendNodeId);
+    if (!destinationQuad) return null;
+    const source =
+      edges.length === 0 ? sourceViewport : await targetViewport(cdp, targetRoot.target);
+    if (!source) return null;
+    const parentTargetRoot = targetRootFrame(byId, parent);
+    if (!parentTargetRoot) return null;
+    const destinationClips = await sameTargetFrameClips(cdp, byId, parent, parentTargetRoot);
+    if (!destinationClips) return null;
+    edges.push({ sourceViewport: source, destinationQuad, destinationClips });
+    targetRoot = parentTargetRoot;
+  }
+
+  const topViewport =
+    edges.length === 0 ? sourceViewport : await targetViewport(cdp, targetRoot.target);
+  return topViewport ? { sourceClips, edges, topViewport } : null;
+}
+
+async function loadFrameGraph(cdp: CdpRunner, tabId: number): Promise<CdpFrameGraph | null> {
+  if (!cdp.getFrameGraph) return null;
+  try {
+    return await cdp.getFrameGraph(tabId);
+  } catch (error) {
+    console.debug("[bsk frame-geometry] frame graph resolution failed", error);
+    return null;
+  }
+}
+
+async function scrollFrameOwners(
+  cdp: CdpRunner,
+  tabId: number,
+  graph: CdpFrameGraph,
+  frameId: string,
+): Promise<RpcError | null> {
+  const byId = frameMap(graph);
+  const ancestry = frameAncestry(graph, frameId);
+  if (!ancestry) return geometryError(`could not resolve frame ancestry for ${frameId}`);
+  for (const child of [...ancestry].reverse()) {
+    const parent = child.parentFrameId ? byId.get(child.parentFrameId) : undefined;
+    if (!parent || child.ownerBackendNodeId === undefined) {
+      return geometryError(`could not resolve frame owner for ${child.frameId}`);
+    }
+    const error = await scrollNodeIntoView(
+      cdpRunnerForTarget(cdp, parent.target),
+      tabId,
+      child.ownerBackendNodeId,
+    );
+    if (error) return error;
+  }
+  return null;
+}
+
+async function scrollElementWithFrameGraph(
+  cdp: CdpRunner,
+  tabId: number,
+  target: CdpTarget,
+  backendNodeId: number,
+  frameId: string | undefined,
+  graph: CdpFrameGraph | null,
+): Promise<RpcError | null> {
+  if (frameId) {
+    if (!graph) return geometryError(`could not resolve frame graph for ${frameId}`);
+    const error = await scrollFrameOwners(cdp, tabId, graph, frameId);
+    if (error) return error;
+  } else if (target.sessionId) {
+    return geometryError("an OOPIF node address requires frameId");
+  }
+  return scrollNodeIntoView(cdpRunnerForTarget(cdp, target), tabId, backendNodeId);
+}
+
+export async function scrollElementAndFramesIntoView(
+  cdp: CdpRunner,
+  tabId: number,
+  target: CdpTarget,
+  backendNodeId: number,
+  frameId?: string,
+): Promise<RpcError | null> {
+  const graph = frameId ? await loadFrameGraph(cdp, tabId) : null;
+  return scrollElementWithFrameGraph(cdp, tabId, target, backendNodeId, frameId, graph);
+}
+
+function largestRegion(regions: Region): Polygon | null {
+  let largest: { polygon: Polygon; area: number } | null = null;
+  for (const polygon of regions) {
+    const area = polygonArea(polygon);
+    if (area <= 0) continue;
+    if (!largest || area > largest.area) largest = { polygon, area };
+  }
+  return largest?.polygon ?? null;
+}
+
+export async function resolveNodeGeometry(
+  cdp: CdpRunner,
+  tabId: number,
+  address: NodeAddress,
+  options: { scrollIntoView?: boolean } = {},
+): Promise<ResolvedNodeGeometry | RpcError> {
+  try {
+    if (address.target.sessionId && !address.frameId) {
+      return geometryError("an OOPIF node address requires frameId");
+    }
+    const graph = address.frameId ? await loadFrameGraph(cdp, tabId) : null;
+    if (address.frameId && !graph) {
+      return geometryError(`could not resolve frame graph for ${address.frameId}`);
+    }
+
+    if (options.scrollIntoView) {
+      const scrollError = await scrollElementWithFrameGraph(
+        cdp,
+        tabId,
+        address.target,
+        address.backendNodeId,
+        address.frameId,
+        graph,
+      );
+      if (scrollError) return scrollError;
+    }
+
+    const localRegion = await nodeContentRegion(
+      cdpRunnerForTarget(cdp, address.target),
+      tabId,
+      address.backendNodeId,
+    );
+    if (isRpcError(localRegion)) return localRegion;
+
+    let topVisibleRegions: Region;
+    if (address.frameId && graph) {
+      const projection = await resolveFrameProjection(cdp, graph, address.frameId);
+      if (!projection)
+        return geometryError(`could not resolve frame geometry for ${address.frameId}`);
+      topVisibleRegions = projectRegionToViewport(localRegion, projection);
+    } else {
+      const viewport = await targetViewport(cdp, address.target);
+      if (!viewport) return geometryError("could not resolve top viewport geometry");
+      topVisibleRegions = localRegion
+        .map((polygon) =>
+          clipPolygon(polygon, rectPolygon({ x: 0, y: 0, w: viewport.width, h: viewport.height })),
+        )
+        .filter((polygon) => polygon.length >= 3);
+    }
+
+    const topBounds = regionBounds(topVisibleRegions);
+    const actionRegion = largestRegion(topVisibleRegions);
+    const actionPoint = actionRegion ? polygonCentroid(actionRegion) : null;
+    if (!topBounds || !actionPoint) {
+      return { code: "permission_denied", message: "element not visible" };
+    }
+    return { topVisibleRegions, topBounds, actionPoint };
+  } catch (error) {
+    return geometryError(error instanceof Error ? error.message : String(error));
+  }
+}

apps/extension/src/tools/geometry.ts

@@ -0,0 +1,266 @@
+export interface Point {
+  x: number;
+  y: number;
+}
+
+export type Polygon = Point[];
+export type Region = Polygon[];
+export type Quad = [Point, Point, Point, Point];
+
+export interface Size {
+  width: number;
+  height: number;
+}
+
+export interface ViewportRect {
+  x: number;
+  y: number;
+  width: number;
+  height: number;
+}
+
+export interface ProjectiveEdge {
+  sourceViewport: Size;
+  destinationQuad: Quad;
+  destinationClips?: Polygon[];
+}
+
+export interface GeometryProjection {
+  sourceClips: Polygon[];
+  edges: ProjectiveEdge[];
+  topViewport: Size;
+}
+
+export function parseCdpQuad(raw: number[] | undefined): Quad | null {
+  if (!raw || raw.length !== 8 || !raw.every(Number.isFinite)) return null;
+  return [
+    { x: raw[0], y: raw[1] },
+    { x: raw[2], y: raw[3] },
+    { x: raw[4], y: raw[5] },
+    { x: raw[6], y: raw[7] },
+  ];
+}
+
+export function rectPolygon(rect: { x: number; y: number; w: number; h: number }): Quad {
+  return [
+    { x: rect.x, y: rect.y },
+    { x: rect.x + rect.w, y: rect.y },
+    { x: rect.x + rect.w, y: rect.y + rect.h },
+    { x: rect.x, y: rect.y + rect.h },
+  ];
+}
+
+export function viewportPolygon(viewport: Size): Quad {
+  return rectPolygon({ x: 0, y: 0, w: viewport.width, h: viewport.height });
+}
+
+/** Project a normalized unit-square point into an arbitrary content quad. */
+export function projectUnitPoint(point: Point, quad: Quad): Point {
+  const [p0, p1, p2, p3] = quad;
+  const dx1 = p1.x - p2.x;
+  const dx2 = p3.x - p2.x;
+  const dx3 = p0.x - p1.x + p2.x - p3.x;
+  const dy1 = p1.y - p2.y;
+  const dy2 = p3.y - p2.y;
+  const dy3 = p0.y - p1.y + p2.y - p3.y;
+
+  let a: number;
+  let b: number;
+  let c: number;
+  let d: number;
+  let e: number;
+  let f: number;
+  let g = 0;
+  let h = 0;
+
+  if (Math.abs(dx3) < 1e-9 && Math.abs(dy3) < 1e-9) {
+    a = p1.x - p0.x;
+    b = p3.x - p0.x;
+    c = p0.x;
+    d = p1.y - p0.y;
+    e = p3.y - p0.y;
+    f = p0.y;
+  } else {
+    const denominator = dx1 * dy2 - dx2 * dy1;
+    if (Math.abs(denominator) < 1e-9) {
+      return {
+        x: p0.x + (p1.x - p0.x) * point.x + (p3.x - p0.x) * point.y,
+        y: p0.y + (p1.y - p0.y) * point.x + (p3.y - p0.y) * point.y,
+      };
+    }
+    g = (dx3 * dy2 - dx2 * dy3) / denominator;
+    h = (dx1 * dy3 - dx3 * dy1) / denominator;
+    a = p1.x - p0.x + g * p1.x;
+    b = p3.x - p0.x + h * p3.x;
+    c = p0.x;
+    d = p1.y - p0.y + g * p1.y;
+    e = p3.y - p0.y + h * p3.y;
+    f = p0.y;
+  }
+
+  const scale = g * point.x + h * point.y + 1;
+  return {
+    x: (a * point.x + b * point.y + c) / scale,
+    y: (d * point.x + e * point.y + f) / scale,
+  };
+}
+
+export function projectPolygon(polygon: Polygon, edge: ProjectiveEdge): Polygon {
+  const { width, height } = edge.sourceViewport;
+  if (width <= 0 || height <= 0) return [];
+  return polygon.map((point) =>
+    projectUnitPoint({ x: point.x / width, y: point.y / height }, edge.destinationQuad),
+  );
+}
+
+function polygonSignedArea(points: Polygon): number {
+  let area = 0;
+  for (let index = 0; index < points.length; index += 1) {
+    const current = points[index];
+    const next = points[(index + 1) % points.length];
+    area += current.x * next.y - next.x * current.y;
+  }
+  return area / 2;
+}
+
+function edgeIntersection(start: Point, end: Point, clipStart: Point, clipEnd: Point): Point {
+  const subjectX = end.x - start.x;
+  const subjectY = end.y - start.y;
+  const clipX = clipEnd.x - clipStart.x;
+  const clipY = clipEnd.y - clipStart.y;
+  const denominator = subjectX * clipY - subjectY * clipX;
+  if (Math.abs(denominator) < 1e-9) return end;
+  const offsetX = clipStart.x - start.x;
+  const offsetY = clipStart.y - start.y;
+  const scale = (offsetX * clipY - offsetY * clipX) / denominator;
+  return { x: start.x + scale * subjectX, y: start.y + scale * subjectY };
+}
+
+/** Clip a polygon to a convex polygon, preserving every resulting vertex. */
+export function clipPolygon(subject: Polygon, clip: Polygon): Polygon {
+  if (subject.length < 3 || clip.length < 3) return [];
+  const orientation = polygonSignedArea(clip) >= 0 ? 1 : -1;
+  let output = [...subject];
+  for (let edge = 0; edge < clip.length && output.length > 0; edge += 1) {
+    const clipStart = clip[edge];
+    const clipEnd = clip[(edge + 1) % clip.length];
+    const input = output;
+    output = [];
+    const inside = (point: Point) =>
+      orientation *
+        ((clipEnd.x - clipStart.x) * (point.y - clipStart.y) -
+          (clipEnd.y - clipStart.y) * (point.x - clipStart.x)) >=
+      -1e-9;
+    let start = input[input.length - 1];
+    for (const end of input) {
+      const startInside = inside(start);
+      const endInside = inside(end);
+      if (endInside) {
+        if (!startInside) output.push(edgeIntersection(start, end, clipStart, clipEnd));
+        output.push(end);
+      } else if (startInside) {
+        output.push(edgeIntersection(start, end, clipStart, clipEnd));
+      }
+      start = end;
+    }
+  }
+  return output;
+}
+
+export function polygonBounds(points: Polygon): ViewportRect | null {
+  if (points.length < 3) return null;
+  const xs = points.map((point) => point.x);
+  const ys = points.map((point) => point.y);
+  const x = Math.min(...xs);
+  const y = Math.min(...ys);
+  const right = Math.max(...xs);
+  const bottom = Math.max(...ys);
+  if (right <= x || bottom <= y) return null;
+  return { x, y, width: right - x, height: bottom - y };
+}
+
+export function regionBounds(region: Region): ViewportRect | null {
+  return polygonBounds(region.flat());
+}
+
+export function polygonArea(points: Polygon): number {
+  return Math.abs(polygonSignedArea(points));
+}
+
+export function polygonCentroid(points: Polygon): Point | null {
+  if (points.length < 3) return null;
+  let twiceArea = 0;
+  let x = 0;
+  let y = 0;
+  for (let index = 0; index < points.length; index += 1) {
+    const current = points[index];
+    const next = points[(index + 1) % points.length];
+    const cross = current.x * next.y - next.x * current.y;
+    twiceArea += cross;
+    x += (current.x + next.x) * cross;
+    y += (current.y + next.y) * cross;
+  }
+  if (Math.abs(twiceArea) < 1e-9) return null;
+  return { x: x / (3 * twiceArea), y: y / (3 * twiceArea) };
+}
+
+export function projectAndClipRegion(
+  region: Region,
+  edges: ProjectiveEdge[],
+  topViewport: Size,
+): Region {
+  let projected = region;
+  for (const edge of edges) {
+    const sourceClip = viewportPolygon(edge.sourceViewport);
+    projected = projected
+      .map((polygon) => clipPolygon(polygon, sourceClip))
+      .filter((polygon) => polygon.length >= 3)
+      .map((polygon) =>
+        [edge.destinationQuad, ...(edge.destinationClips ?? [])].reduce(
+          (current, clip) => clipPolygon(current, clip),
+          projectPolygon(polygon, edge),
+        ),
+      )
+      .filter((polygon) => polygon.length >= 3);
+  }
+  const topClip = viewportPolygon(topViewport);
+  return projected
+    .map((polygon) => clipPolygon(polygon, topClip))
+    .filter((polygon) => polygon.length >= 3);
+}
+
+export function projectRegionToViewport(region: Region, projection: GeometryProjection): Region {
+  const clipped = region
+    .map((polygon) =>
+      projection.sourceClips.reduce((current, clip) => clipPolygon(current, clip), polygon),
+    )
+    .filter((polygon) => polygon.length >= 3);
+  return projectAndClipRegion(clipped, projection.edges, projection.topViewport);
+}
+
+export function projectRectToViewport(
+  rect: { x: number; y: number; w: number; h: number } | null,
+  projection: GeometryProjection,
+): ViewportRect | null {
+  if (!rect) return null;
+  return regionBounds(projectRegionToViewport([rectPolygon(rect)], projection));
+}
+
+export function childFrameProjection(
+  parent: GeometryProjection,
+  ownerRectInParent: { x: number; y: number; w: number; h: number },
+): GeometryProjection {
+  const destinationQuad = rectPolygon(ownerRectInParent);
+  return {
+    sourceClips: [],
+    edges: [
+      {
+        sourceViewport: { width: ownerRectInParent.w, height: ownerRectInParent.h },
+        destinationQuad,
+        destinationClips: parent.sourceClips,
+      },
+      ...parent.edges,
+    ],
+    topViewport: parent.topViewport,
+  };
+}

apps/extension/src/tools/human-loop.ts

@@ -8,6 +8,7 @@ import {
   HELP_REQUEST,
   type HelpCancelMessage,
   type HelpFinishMessage,
+  type HelpHighlightRect,
   type HelpQueryResponse,
   type HelpRequestMessage,
   isHelpAckMessage,
@@ -25,6 +26,7 @@ import type {
   ResolvedTarget,
   RpcError,
 } from "@/transport/types";
+import { resolveNodeGeometry } from "./frame-geometry";
 import {
   type CdpRunner,
   type ChromeTabsApi,
@@ -37,7 +39,6 @@ import {
 import { lookupSnapshotRef } from "./snapshot-ref";
 
 const DEFAULT_HELP_TIMEOUT_MS = 300_000;
-const HELP_ATTR = "data-bsk-help";
 const HELP_SEND_RETRIES = 3;
 const HELP_SEND_RETRY_DELAY_MS = 350;
 const HELP_REARM_DEBOUNCE_MS = 150;
@@ -74,6 +75,7 @@ interface ActiveHelpRequest {
   title?: string;
   targets: HelpTarget[];
   selectors: string[];
+  rects: HelpHighlightRect[];
   timeoutMs: number;
   notificationId: string;
   resolvedTargets?: ResolvedTarget[];
@@ -134,6 +136,7 @@ function helpRequestMessage(help: ActiveHelpRequest, tabId: number): HelpRequest
     ...(help.title ? { title: help.title } : {}),
     displayMode: isPrimaryTab ? "full" : "compact",
     selectors: isPrimaryTab ? help.selectors : [],
+    rects: isPrimaryTab ? help.rects : [],
     timeoutMs: help.timeoutMs,
   };
 }
@@ -165,33 +168,6 @@ async function sendHelpRequestWithAck(
   throw lastError ?? new Error("failed to show help overlay");
 }
 
-async function tagRefTarget(
-  cdp: CdpRunner,
-  tabId: number,
-  backendNodeId: number,
-  index: number,
-): Promise<string | null> {
-  let objectId: string | undefined;
-  try {
-    const resolved = await cdp.send<{ object?: { objectId?: string } }>(tabId, "DOM.resolveNode", {
-      backendNodeId,
-    });
-    objectId = resolved.object?.objectId;
-    if (!objectId) return null;
-    await cdp.send(tabId, "Runtime.callFunctionOn", {
-      objectId,
-      functionDeclaration: `function(){ this.setAttribute("${HELP_ATTR}", "${index}"); }`,
-    });
-    return `[${HELP_ATTR}="${index}"]`;
-  } catch {
-    return null;
-  } finally {
-    if (objectId) {
-      await cdp.send(tabId, "Runtime.releaseObject", { objectId }).catch(() => {});
-    }
-  }
-}
-
 async function selectorExists(
   cdp: CdpRunner,
   tabId: number,
@@ -209,36 +185,22 @@ async function selectorExists(
   }
 }
 
-async function clearRefTags(cdp: CdpRunner | undefined, tabId: number): Promise<void> {
-  if (!cdp) return;
-  try {
-    const doc = await cdp.send<{ root?: { nodeId?: number } }>(tabId, "DOM.getDocument", {
-      depth: 0,
-    });
-    const rootId = doc.root?.nodeId;
-    if (rootId === undefined) return;
-    const { nodeIds } = await cdp.send<{ nodeIds: number[] }>(tabId, "DOM.querySelectorAll", {
-      nodeId: rootId,
-      selector: `[${HELP_ATTR}]`,
-    });
-    for (const nodeId of nodeIds ?? []) {
-      await cdp.send(tabId, "DOM.removeAttribute", { nodeId, name: HELP_ATTR }).catch(() => {});
-    }
-  } catch {
-    // Best-effort cleanup.
-  }
-}
-
 async function resolveHelpTargets(
   ctx: ReturnType<SessionManager["get"]>,
   tabId: number,
   targets: HelpTarget[],
   deps: RequestHelpDeps,
-): Promise<{ selectors: string[]; resolvedTargets?: ResolvedTarget[] }> {
+  options: { scrollIntoView: boolean },
+): Promise<{
+  selectors: string[];
+  rects: HelpHighlightRect[];
+  resolvedTargets?: ResolvedTarget[];
+}> {
   const selectors: string[] = [];
+  const rects: HelpHighlightRect[] = [];
   const resolved: ResolvedTarget[] = [];
   let rootNodeId: number | undefined;
-  if (deps.cdp && targets.length > 0) {
+  if (deps.cdp && targets.some((target) => Boolean(target.selector))) {
     try {
       const doc = await deps.cdp.send<{ root?: { nodeId?: number } }>(tabId, "DOM.getDocument", {
         depth: 0,
@@ -262,28 +224,55 @@ async function resolveHelpTargets(
       resolved.push({ matched, selector: tgt.selector });
     } else if (tgt.ref) {
       const looked = ctx ? lookupSnapshotRef(ctx, tgt.ref, tabId) : null;
-      const backendNodeId = looked?.backendNodeId ?? null;
-      let sel: string | null = null;
-      if (backendNodeId !== null && deps.cdp) {
-        sel = await tagRefTarget(deps.cdp, tabId, backendNodeId, i);
+      let rect: HelpHighlightRect | null = null;
+      if (looked && deps.cdp) {
+        const target = {
+          tabId,
+          ...(looked.cdpSessionId ? { sessionId: looked.cdpSessionId } : {}),
+        };
+        const geometry = await resolveNodeGeometry(
+          deps.cdp,
+          tabId,
+          {
+            target,
+            backendNodeId: looked.backendNodeId,
+            ...(looked.frameId ? { frameId: looked.frameId } : {}),
+          },
+          { scrollIntoView: options.scrollIntoView },
+        );
+        if (!isRpcError(geometry)) {
+          rect = {
+            top: geometry.topBounds.y,
+            left: geometry.topBounds.x,
+            width: geometry.topBounds.width,
+            height: geometry.topBounds.height,
+          };
+        }
       }
-      if (sel) selectors.push(sel);
-      resolved.push({ matched: sel !== null, ref: tgt.ref });
+      if (rect) rects.push(rect);
+      resolved.push({
+        matched: rect !== null,
+        ref: tgt.ref,
+      });
     }
   }
 
-  return { selectors, resolvedTargets: resolved.length > 0 ? resolved : undefined };
+  return { selectors, rects, resolvedTargets: resolved.length > 0 ? resolved : undefined };
 }
 
-async function refreshHelpTargets(help: ActiveHelpRequest): Promise<void> {
-  await clearRefTags(help.deps.cdp, help.primaryTabId);
-  const { selectors, resolvedTargets } = await resolveHelpTargets(
+async function refreshHelpTargets(
+  help: ActiveHelpRequest,
+  options: { scrollIntoView: boolean } = { scrollIntoView: true },
+): Promise<void> {
+  const { selectors, rects, resolvedTargets } = await resolveHelpTargets(
     help.ctx,
     help.primaryTabId,
     help.targets,
     help.deps,
+    options,
   );
   help.selectors = selectors;
+  help.rects = rects;
   help.resolvedTargets = resolvedTargets;
 }
 
@@ -294,12 +283,7 @@ async function cleanupHelp(help: ActiveHelpRequest): Promise<void> {
   const tabsToCancel = new Set([help.primaryTabId, ...help.overlayTabIds]);
   await Promise.all(
     [...tabsToCancel].map((tabId) =>
-      Promise.all([
-        clearRefTags(help.deps.cdp, tabId),
-        help.deps
-          .sendToTab(tabId, { type: HELP_CANCEL, requestId: help.requestId })
-          .catch(() => {}),
-      ]),
+      help.deps.sendToTab(tabId, { type: HELP_CANCEL, requestId: help.requestId }).catch(() => {}),
     ),
   );
 }
@@ -476,7 +460,9 @@ function attachHelpRuntimeListener(deps: RequestHelpDeps): () => void {
           sendResponse({ active: false });
           return;
         }
-        if (tabId === help.primaryTabId) await refreshHelpTargets(help);
+        if (tabId === help.primaryTabId) {
+          await refreshHelpTargets(help, { scrollIntoView: false });
+        }
         help.overlayTabIds.add(tabId);
         sendResponse({
           active: true,
@@ -486,6 +472,7 @@ function attachHelpRuntimeListener(deps: RequestHelpDeps): () => void {
             ...(help.title ? { title: help.title } : {}),
             displayMode: tabId === help.primaryTabId ? "full" : "compact",
             selectors: tabId === help.primaryTabId ? help.selectors : [],
+            rects: tabId === help.primaryTabId ? help.rects : [],
             timeoutMs: help.timeoutMs,
           },
         });
@@ -686,7 +673,13 @@ export async function handleRequestHelp(
   if (deps.autoAttachLifecycle !== false) ensureHelpLifecycleListeners(deps);
   const tabId = target.tabId;
   const initialTargets = params.targets ?? [];
-  const { selectors, resolvedTargets } = await resolveHelpTargets(ctx, tabId, initialTargets, deps);
+  const { selectors, rects, resolvedTargets } = await resolveHelpTargets(
+    ctx,
+    tabId,
+    initialTargets,
+    deps,
+    { scrollIntoView: true },
+  );
 
   await deps.windows.update(target.windowId, { focused: true }).catch(() => {});
   await deps.activateTab(tabId).catch(() => {});
@@ -729,6 +722,7 @@ export async function handleRequestHelp(
       ...(params.title ? { title: params.title } : {}),
       targets: initialTargets,
       selectors,
+      rects,
       timeoutMs,
       notificationId,
       resolvedTargets,

apps/extension/src/tools/interaction.ts

@@ -3,14 +3,15 @@
 //
 // All interaction tools:
 // 1. Resolve target tab (sandbox: must be inside Agent Window).
-// 2. Resolve target element by `ref` (RefStore.resolve with tabId
-//    binding) or `selector` (DOM.querySelector + describeNode).
-// 3. Scroll the node into view, then dispatch the appropriate
-//    `Input.*` CDP events.
+// 2. Resolve target element by `ref` (compound frame/session identity)
+//    or `selector` (DOM.querySelector + describeNode).
+// 3. Scroll the node and its frame owners into view, project its live
+//    content quad into the top viewport, then dispatch `Input.*` events.
 // 4. Honour `AbortSignal` so canceled calls don't issue follow-up CDP
 //    commands.
 
 import { ChromiumCdp } from "@/browser-driver/chromium-cdp";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
 import type { SessionContext, SessionManager } from "@/session-manager/manager";
 import type {
   ClickParams,
@@ -28,17 +29,13 @@ import type {
   SelectResult,
 } from "@/transport/types";
 import { attachDialogs, markDialogCursor } from "./dialogs";
-import {
-  backendNodeToObject,
-  boxCentre,
-  nodeCentre,
-  quadCentre,
-  scrollNodeIntoView,
-} from "./element-geometry";
+import { backendNodeToObject } from "./element-geometry";
 import { rpcError } from "./errors";
+import { resolveNodeGeometry, scrollElementAndFramesIntoView } from "./frame-geometry";
 import {
   type CdpRunner,
   type ChromeTabsApi,
+  cdpRunnerForTarget,
   chromeTabsApi,
   enforceAgentWindow,
   isRpcError,
@@ -137,7 +134,16 @@ async function resolveBackendNode(
   target: { tabId: number },
   params: { ref?: string; selector?: string },
   toolName: string,
-): Promise<{ backendNodeId: number; usedRef?: string; usedSelector?: string } | RpcError> {
+): Promise<
+  | {
+      backendNodeId: number;
+      cdpTarget: CdpTarget;
+      frameId?: string;
+      usedRef?: string;
+      usedSelector?: string;
+    }
+  | RpcError
+> {
   const hasRef = typeof params.ref === "string" && params.ref.length > 0;
   const hasSelector = typeof params.selector === "string" && params.selector.length > 0;
   if (hasRef && hasSelector) {
@@ -155,7 +161,15 @@ async function resolveBackendNode(
   if (hasRef) {
     const resolved = resolveSnapshotRef(ctx, params.ref as string, target.tabId);
     if (isRpcError(resolved)) return resolved;
-    return { backendNodeId: resolved.backendNodeId, usedRef: resolved.refKey };
+    return {
+      backendNodeId: resolved.backendNodeId,
+      cdpTarget: {
+        tabId: target.tabId,
+        ...(resolved.cdpSessionId ? { sessionId: resolved.cdpSessionId } : {}),
+      },
+      ...(resolved.frameId ? { frameId: resolved.frameId } : {}),
+      usedRef: resolved.refKey,
+    };
   }
   // selector path
   try {
@@ -192,7 +206,7 @@ async function resolveBackendNode(
         message: "DOM.describeNode returned no backendNodeId",
       };
     }
-    return { backendNodeId, usedSelector: params.selector };
+    return { backendNodeId, cdpTarget: { tabId: target.tabId }, usedSelector: params.selector };
   } catch (err) {
     return {
       code: "cdp_failed",
@@ -228,19 +242,19 @@ export async function handleClick(
     return { code: "cancelled", message: "click aborted" };
   }
 
-  try {
-    deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
-    const scrollErr = await scrollNodeIntoView(deps.cdp, target.tabId, node.backendNodeId);
-    if (scrollErr) return scrollErr;
-  } catch (err) {
-    return {
-      code: "cdp_failed",
-      message: err instanceof Error ? err.message : String(err),
-    };
-  }
-
-  const centre = await nodeCentre(deps.cdp, target.tabId, node.backendNodeId);
-  if (isRpcError(centre)) return centre;
+  deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
+  const geometry = await resolveNodeGeometry(
+    deps.cdp,
+    target.tabId,
+    {
+      target: node.cdpTarget,
+      backendNodeId: node.backendNodeId,
+      ...(node.frameId ? { frameId: node.frameId } : {}),
+    },
+    { scrollIntoView: true },
+  );
+  if (isRpcError(geometry)) return geometry;
+  const centre = geometry.actionPoint;
 
   if (throwIfAborted(deps.signal)) {
     return { code: "cancelled", message: "click aborted" };
@@ -353,19 +367,19 @@ export async function handleHover(
   const node = await resolveBackendNode(deps.cdp, ctx, target, params, "hover");
   if (isRpcError(node)) return node;
 
-  try {
-    deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
-    const scrollErr = await scrollNodeIntoView(deps.cdp, target.tabId, node.backendNodeId);
-    if (scrollErr) return scrollErr;
-  } catch (err) {
-    return {
-      code: "cdp_failed",
-      message: err instanceof Error ? err.message : String(err),
-    };
-  }
-
-  const centre = await nodeCentre(deps.cdp, target.tabId, node.backendNodeId);
-  if (isRpcError(centre)) return centre;
+  deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
+  const geometry = await resolveNodeGeometry(
+    deps.cdp,
+    target.tabId,
+    {
+      target: node.cdpTarget,
+      backendNodeId: node.backendNodeId,
+      ...(node.frameId ? { frameId: node.frameId } : {}),
+    },
+    { scrollIntoView: true },
+  );
+  if (isRpcError(geometry)) return geometry;
+  const centre = geometry.actionPoint;
 
   if (throwIfAborted(deps.signal)) {
     return { code: "cancelled", message: "hover aborted" };
@@ -585,10 +599,11 @@ export async function handleFill(
 
   const node = await resolveBackendNode(deps.cdp, ctx, target, params, "fill");
   if (isRpcError(node)) return node;
+  const nodeCdp = cdpRunnerForTarget(deps.cdp, node.cdpTarget);
 
   try {
     deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
-    const described = await deps.cdp.send<{ node?: DescribedNode }>(
+    const described = await nodeCdp.send<{ node?: DescribedNode }>(
       target.tabId,
       "DOM.describeNode",
       {
@@ -602,12 +617,18 @@ export async function handleFill(
         `element ${described.node?.nodeName ?? "?"} not fillable (need input/textarea/contenteditable)`,
       );
     }
-    const scrollErr = await scrollNodeIntoView(deps.cdp, target.tabId, node.backendNodeId);
+    const scrollErr = await scrollElementAndFramesIntoView(
+      deps.cdp,
+      target.tabId,
+      node.cdpTarget,
+      node.backendNodeId,
+      node.frameId,
+    );
     if (scrollErr) return scrollErr;
     if (throwIfAborted(deps.signal)) {
       return { code: "cancelled", message: "fill aborted" };
     }
-    await deps.cdp.send(target.tabId, "DOM.focus", { backendNodeId: node.backendNodeId });
+    await nodeCdp.send(target.tabId, "DOM.focus", { backendNodeId: node.backendNodeId });
   } catch (err) {
     return {
       code: "cdp_failed",
@@ -619,7 +640,7 @@ export async function handleFill(
     return { code: "cancelled", message: "fill aborted" };
   }
 
-  const objectIdOrErr = await backendNodeToObject(deps.cdp, target.tabId, node.backendNodeId);
+  const objectIdOrErr = await backendNodeToObject(nodeCdp, target.tabId, node.backendNodeId);
   if (isRpcError(objectIdOrErr)) return objectIdOrErr;
   const objectId = objectIdOrErr;
   const clearBefore = params.clear_before ?? true;
@@ -628,7 +649,7 @@ export async function handleFill(
     if (clearBefore) {
       // Clear input/textarea value or wipe contenteditable innerText,
       // then fire `input` so frameworks observe the empty state.
-      await deps.cdp.send(target.tabId, "Runtime.callFunctionOn", {
+      await nodeCdp.send(target.tabId, "Runtime.callFunctionOn", {
         objectId,
         functionDeclaration: `function() {
           if (this.isContentEditable) { this.textContent = ''; }
@@ -655,7 +676,7 @@ export async function handleFill(
       return { code: "cancelled", message: "fill aborted" };
     }
     // Fire `input` + `change` so React / Vue controlled inputs commit.
-    await deps.cdp.send(target.tabId, "Runtime.callFunctionOn", {
+    await nodeCdp.send(target.tabId, "Runtime.callFunctionOn", {
       objectId,
       functionDeclaration: `function() {
         this.dispatchEvent(new Event('input', { bubbles: true }));
@@ -853,14 +874,21 @@ export async function handlePress(
   if (params.ref || params.selector) {
     const node = await resolveBackendNode(deps.cdp, ctx, target, params, "press");
     if (isRpcError(node)) return node;
+    const nodeCdp = cdpRunnerForTarget(deps.cdp, node.cdpTarget);
     try {
       deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
-      const scrollErr = await scrollNodeIntoView(deps.cdp, target.tabId, node.backendNodeId);
+      const scrollErr = await scrollElementAndFramesIntoView(
+        deps.cdp,
+        target.tabId,
+        node.cdpTarget,
+        node.backendNodeId,
+        node.frameId,
+      );
       if (scrollErr) return scrollErr;
       if (throwIfAborted(deps.signal)) {
         return { code: "cancelled", message: "press aborted" };
       }
-      await deps.cdp.send(target.tabId, "DOM.focus", { backendNodeId: node.backendNodeId });
+      await nodeCdp.send(target.tabId, "DOM.focus", { backendNodeId: node.backendNodeId });
     } catch (err) {
       return {
         code: "cdp_failed",
@@ -965,10 +993,11 @@ export async function handleSelect(
 
   const node = await resolveBackendNode(deps.cdp, ctx, target, params, "select");
   if (isRpcError(node)) return node;
+  const nodeCdp = cdpRunnerForTarget(deps.cdp, node.cdpTarget);
 
   try {
     deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
-    const described = await deps.cdp.send<{ node?: DescribedNode }>(
+    const described = await nodeCdp.send<{ node?: DescribedNode }>(
       target.tabId,
       "DOM.describeNode",
       { backendNodeId: node.backendNodeId },
@@ -991,12 +1020,18 @@ export async function handleSelect(
         "single-select <select> requires exactly one value",
       );
     }
-    const scrollErr = await scrollNodeIntoView(deps.cdp, target.tabId, node.backendNodeId);
+    const scrollErr = await scrollElementAndFramesIntoView(
+      deps.cdp,
+      target.tabId,
+      node.cdpTarget,
+      node.backendNodeId,
+      node.frameId,
+    );
     if (scrollErr) return scrollErr;
     if (throwIfAborted(deps.signal)) {
       return { code: "cancelled", message: "select aborted" };
     }
-    await deps.cdp.send(target.tabId, "DOM.focus", { backendNodeId: node.backendNodeId });
+    await nodeCdp.send(target.tabId, "DOM.focus", { backendNodeId: node.backendNodeId });
   } catch (err) {
     return {
       code: "cdp_failed",
@@ -1008,12 +1043,12 @@ export async function handleSelect(
     return { code: "cancelled", message: "select aborted" };
   }
 
-  const objectIdOrErr = await backendNodeToObject(deps.cdp, target.tabId, node.backendNodeId);
+  const objectIdOrErr = await backendNodeToObject(nodeCdp, target.tabId, node.backendNodeId);
   if (isRpcError(objectIdOrErr)) return objectIdOrErr;
   const objectId = objectIdOrErr;
 
   try {
-    const evaluated = await deps.cdp.send<{
+    const evaluated = await nodeCdp.send<{
       result?: { value?: SelectMutationResult | null };
     }>(target.tabId, "Runtime.callFunctionOn", {
       objectId,
@@ -1072,9 +1107,6 @@ export async function handleSelect(
 
 export const __testing__ = {
   DEFAULT_TIMEOUT_MS,
-  quadCentre,
-  boxCentre,
   resolveBackendNode,
-  nodeCentre,
   isFillable,
 };

apps/extension/src/tools/observation.ts

@@ -10,9 +10,11 @@ import {
   isVomReferenceNode,
   renderVom,
   type VomNode,
+  type VomOptions,
   type VomScene,
 } from "@browser-skill/vom";
 import { ChromiumCdp } from "@/browser-driver/chromium-cdp";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
 import {
   type CaptureSuppressSendToTab,
   withOverlaysHiddenForCapture,
@@ -30,8 +32,8 @@ import type {
   SnapshotResult,
 } from "@/transport/types";
 import { attachDialogs, markDialogCursor } from "./dialogs";
-import { nodeBoundingRect, scrollNodeIntoView } from "./element-geometry";
 import { rpcError } from "./errors";
+import { resolveNodeGeometry } from "./frame-geometry";
 import {
   type ChromeTabsApi,
   enforceToolTargetScope,
@@ -40,6 +42,7 @@ import {
   type ResolvedTargetTab,
   resolveCdpAccessibleTargetTab,
   type CdpRunner as SharedCdpRunner,
+  sendToCdpTarget,
   normaliseRef as sharedNormaliseRef,
   type ToolEffect,
 } from "./shared";
@@ -51,6 +54,10 @@ import {
   collectOverlayExcludedBackendIds,
 } from "./vom/capture";
 import { type CapturedFrameDocument, captureFrameData } from "./vom/frame-capture";
+import {
+  type CaptureVomObservationResult,
+  projectRecordSafeObservation,
+} from "./vom/record-safe-observation";
 
 // ---------------------------------------------------------------------------
 // Shared helpers (legacy aliases — observation.ts kept exporting these
@@ -163,26 +170,30 @@ function throwIfAborted(signal: AbortSignal | undefined, tool: string): void {
 async function captureElementScreenshot(
   cdp: SharedCdpRunner,
   tabId: number,
+  target: CdpTarget,
   backendNodeId: number,
+  frameId?: string,
   signal?: AbortSignal,
 ): Promise<{ image_base64: string; width: number; height: number } | RpcError> {
   if (signal?.aborted) return cancelled("screenshot");
-  const scrollErr = await scrollNodeIntoView(cdp, tabId, backendNodeId);
-  if (scrollErr) return scrollErr;
-  if (signal?.aborted) return cancelled("screenshot");
-
-  const rectOrErr = await nodeBoundingRect(cdp, tabId, backendNodeId);
-  if (isRpcError(rectOrErr)) return rectOrErr;
+  const geometry = await resolveNodeGeometry(
+    cdp,
+    tabId,
+    { target, backendNodeId, ...(frameId ? { frameId } : {}) },
+    { scrollIntoView: true },
+  );
+  if (isRpcError(geometry)) return geometry;
   if (signal?.aborted) return cancelled("screenshot");
+  const rect = geometry.topBounds;
 
   try {
     const shot = await cdp.send<{ data?: string }>(tabId, "Page.captureScreenshot", {
       format: "png",
       clip: {
-        x: rectOrErr.x,
-        y: rectOrErr.y,
-        width: rectOrErr.width,
-        height: rectOrErr.height,
+        x: rect.x,
+        y: rect.y,
+        width: rect.width,
+        height: rect.height,
         scale: 1,
       },
     });
@@ -192,8 +203,8 @@ async function captureElementScreenshot(
       return { code: "cdp_failed", message: "Page.captureScreenshot returned no data" };
     }
     const dims = parsePngDimensions(image_base64) ?? {
-      width: Math.round(rectOrErr.width),
-      height: Math.round(rectOrErr.height),
+      width: Math.round(rect.width),
+      height: Math.round(rect.height),
     };
     return { image_base64, width: dims.width, height: dims.height };
   } catch (err) {
@@ -297,9 +308,21 @@ export async function handleScreenshot(
     await deps.cdp.ensureAttachedToUrl?.(target.tabId, target.url);
     if (signal?.aborted) return cancelled("screenshot");
     const cdp = deps.cdp;
+    const nodeTarget = {
+      tabId: target.tabId,
+      ...(node.cdpSessionId ? { sessionId: node.cdpSessionId } : {}),
+    };
     const captured = await withOverlaysHiddenForCapture(
       target.tabId,
-      () => captureElementScreenshot(cdp, target.tabId, node.backendNodeId, signal),
+      () =>
+        captureElementScreenshot(
+          cdp,
+          target.tabId,
+          nodeTarget,
+          node.backendNodeId,
+          node.frameId,
+          signal,
+        ),
       deps.sendToTab,
     );
     if (isRpcError(captured)) return captured;
@@ -393,7 +416,15 @@ function isModalSignal(
 
 function isSensitive(capturedNode: CapturedNode | undefined): boolean {
   const attrs = capturedNode?.attrs ?? {};
-  return (attrs.type ?? "").toLowerCase() === "password";
+  const type = (attrs.type ?? "").toLowerCase();
+  if (type === "password") return true;
+  const autocomplete = (attrs.autocomplete ?? "").toLowerCase();
+  return (
+    autocomplete.startsWith("cc-") ||
+    autocomplete === "one-time-code" ||
+    autocomplete === "current-password" ||
+    autocomplete === "new-password"
+  );
 }
 
 interface AxNodeSignals {
@@ -443,7 +474,13 @@ const AX_TEXT_STOP_ROLES = new Set([
   "columnheader",
   "rowheader",
 ]);
-const SENSITIVE_AX_INPUT_TYPES = new Set(["password", "credit-card"]);
+const SENSITIVE_AX_INPUT_TYPES = new Set([
+  "password",
+  "credit-card",
+  "one-time-code",
+  "current-password",
+  "new-password",
+]);
 
 function axPropertyString(axNode: CdpAxNode, name: string): string | undefined {
   const prop = axNode.properties?.find((item) => item.name === name);
@@ -1280,7 +1317,7 @@ export function buildFrameVomScene(
           excludedBackendNodeIds:
             frameId === rootFrameId ? captured.excludedBackendNodeIds : new Set(),
         },
-        { pageUrl: options.pageUrl },
+        { pageUrl: document.url ?? options.pageUrl },
       ),
     );
   }
@@ -1452,9 +1489,15 @@ export async function handleGetHtml(
     if (params.ref) {
       const resolved = resolveSnapshotRef(ctx, params.ref, target.tabId);
       if (isRpcError(resolved)) return resolved;
-      const resp = await deps.cdp.send<{ outerHTML?: string }>(target.tabId, "DOM.getOuterHTML", {
-        backendNodeId: resolved.backendNodeId,
-      });
+      const resp = await sendToCdpTarget<{ outerHTML?: string }>(
+        deps.cdp,
+        {
+          tabId: target.tabId,
+          ...(resolved.cdpSessionId ? { sessionId: resolved.cdpSessionId } : {}),
+        },
+        "DOM.getOuterHTML",
+        { backendNodeId: resolved.backendNodeId },
+      );
       throwIfAborted(signal, "get_html");
       html = resp.outerHTML ?? "";
     } else {
@@ -1513,14 +1556,13 @@ async function fallbackCapturedViewModel(
   try {
     const metrics = await cdp.send<LayoutMetricsViewportReply>(tabId, "Page.getLayoutMetrics", {});
     throwIfAborted(signal, "observation");
-    const vpSrc = metrics.cssLayoutViewport ?? metrics.layoutViewport ?? {};
+    const source = metrics.cssLayoutViewport ?? metrics.layoutViewport ?? {};
     viewport = {
-      width: vpSrc.clientWidth ?? 0,
-      height: vpSrc.clientHeight ?? 0,
+      width: source.clientWidth ?? 0,
+      height: source.clientHeight ?? 0,
     };
-  } catch (err) {
-    if (isAbortError(err)) throw err;
-    // viewport stays zero-sized
+  } catch (error) {
+    if (isAbortError(error)) throw error;
   }
   const excludedBackendNodeIds = await collectOverlayExcludedBackendIds(cdp, tabId, signal);
   throwIfAborted(signal, "observation");
@@ -1530,22 +1572,58 @@ async function fallbackCapturedViewModel(
 async function captureForVom(
   cdp: CdpRunner,
   tabId: number,
-  conditionalSurfaceProbe: boolean,
-  hoverProbeBypassOverlay?: (tabId: number, enabled: boolean) => Promise<void>,
-  signal?: AbortSignal,
+  options: CaptureVomObservationOptions,
 ): Promise<CapturedViewModel> {
   try {
     return await captureViewModel(cdp, tabId, {
-      conditionalSurfaceProbe,
-      hoverProbeBypassOverlay,
-      signal,
+      conditionalSurfaceProbe: options.conditionalSurfaceProbe ?? false,
+      hoverProbeBypassOverlay: options.hoverProbeBypassOverlay,
+      signal: options.signal,
     });
-  } catch (err) {
-    if (isAbortError(err)) throw err;
-    return fallbackCapturedViewModel(cdp, tabId, signal);
+  } catch (error) {
+    if (isAbortError(error)) throw error;
+    return fallbackCapturedViewModel(cdp, tabId, options.signal);
   }
 }
 
+export interface CaptureVomObservationOptions extends VomOptions {
+  conditionalSurfaceProbe?: boolean;
+  hoverProbeBypassOverlay?: (tabId: number, enabled: boolean) => Promise<void>;
+  signal?: AbortSignal;
+}
+
+export async function captureVomObservation(
+  cdp: CdpRunner,
+  tabId: number,
+  url: string | undefined,
+  options: CaptureVomObservationOptions = {},
+): Promise<CaptureVomObservationResult> {
+  throwIfAborted(options.signal, "observation");
+  await cdp.ensureAttachedToUrl?.(tabId, url);
+  throwIfAborted(options.signal, "observation");
+  const captured = await captureForVom(cdp, tabId, options);
+  throwIfAborted(options.signal, "observation");
+  const documents = await captureFrameData<CdpAxNode>(cdp, tabId, captured, options.signal);
+  throwIfAborted(options.signal, "observation");
+  const scene =
+    captured.rootFrameId && captured.frameNodes?.size
+      ? buildFrameVomScene(documents, captured, { pageUrl: url })
+      : buildVomScene(documents[0]?.axNodes ?? [], captured, { pageUrl: url });
+  const rendered = renderVom(scene, {
+    maxDepth: options.maxDepth,
+    maxTokens: options.maxTokens,
+    redactValues: options.redactValues,
+    activeRegionPolicy: options.activeRegionPolicy,
+  });
+  throwIfAborted(options.signal, "observation");
+  return projectRecordSafeObservation({
+    rootFrameId: captured.rootFrameId ?? documents[0]?.frameId ?? "root",
+    frameDocuments: documents,
+    rendered,
+    surfaceProbes: captured.surfaceProbes,
+  });
+}
+
 async function handleVomObservation(
   manager: SessionManager,
   params: SnapshotParams | ObserveParams,
@@ -1575,49 +1653,43 @@ async function handleVomObservation(
   try {
     throwIfAborted(signal, toolName);
     deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
-    await deps.cdp.ensureAttachedToUrl?.(target.tabId, target.url);
-    throwIfAborted(signal, toolName);
     const effectiveConditionalSurfaceProbe =
       deps.conditionalSurfaceProbe ?? conditionalSurfaceProbe;
-    const captured = await captureForVom(
-      deps.cdp,
-      target.tabId,
-      effectiveConditionalSurfaceProbe,
-      deps.hoverProbeBypassOverlay,
-      signal,
-    );
-    throwIfAborted(signal, toolName);
-    const frameDocuments = await captureFrameData<CdpAxNode>(
-      deps.cdp,
-      target.tabId,
-      captured,
-      signal,
-    );
-    throwIfAborted(signal, toolName);
-    const scene =
-      captured.rootFrameId && captured.frameNodes?.size
-        ? buildFrameVomScene(frameDocuments, captured, { pageUrl: target.url })
-        : buildVomScene(frameDocuments[0]?.axNodes ?? [], captured, { pageUrl: target.url });
-    const rendered = renderVom(scene, {
+    const observation = await captureVomObservation(deps.cdp, target.tabId, target.url, {
       maxDepth: params.max_depth,
       maxTokens: params.max_tokens,
       activeRegionPolicy: true,
+      conditionalSurfaceProbe: effectiveConditionalSurfaceProbe,
+      hoverProbeBypassOverlay: deps.hoverProbeBypassOverlay,
+      signal,
     });
     throwIfAborted(signal, toolName);
+    const targetByFrameId = new Map(
+      observation.frames.map((frame) => [frame.frameId, frame.target]),
+    );
     ctx.refStore.replace(
-      rendered.refs.map(
-        (ref) => [ref.ref, { backendNodeId: ref.backendNodeId, tabId: target.tabId }] as const,
-      ),
+      observation.refs.map((ref) => {
+        const refTarget = ref.frameId ? targetByFrameId.get(ref.frameId) : undefined;
+        return [
+          ref.ref,
+          {
+            backendNodeId: ref.backendNodeId,
+            tabId: target.tabId,
+            ...(ref.frameId ? { frameId: ref.frameId } : {}),
+            ...(refTarget?.sessionId ? { cdpSessionId: refTarget.sessionId } : {}),
+          },
+        ] as const;
+      }),
     );
     return attachDialogs(deps.cdp, target.tabId, dialogCursor, {
-      text: rendered.text,
-      ref_count: rendered.refs.length,
+      text: observation.text,
+      ref_count: observation.refs.length,
       tab_id: target.tabId,
-      truncated: rendered.truncated,
+      truncated: observation.truncated,
       ...(toolName === "observe" && (params as ObserveParams).debug_surfaces
         ? {
             debug: {
-              surface_probes: (captured.surfaceProbes ?? []).map((probe) => ({
+              surface_probes: (observation.surfaceProbes ?? []).map((probe) => ({
                 trigger_backend_node_id: probe.triggerBackendNodeId,
                 ...(probe.triggerPoint ? { trigger_point: probe.triggerPoint } : {}),
                 trigger_action: probe.triggerAction,

apps/extension/src/tools/record.ts

@@ -17,11 +17,11 @@ import {
   type RecordStartMessage,
   type RecordStopMessage,
 } from "@/lib/record-bridge";
-import { appendRecordedPayload, observeRecordedNavigation } from "@/lib/recording-step-buffer";
-import { reduceTraceSteps, resolveTraceStartUrl } from "@/lib/trace-reducer";
+import { appendRecordedPayload, observeRecordedNavigation } from "@/lib/recording/step-buffer";
+import { buildTraceV2 } from "@/lib/recording/trace-reducer-v2";
+import type { RecordingDraftStep } from "@/lib/recording/types";
 import type { SessionManager } from "@/session-manager/manager";
 import type {
-  DraftTraceStep,
   RecordAwaitParams,
   RecordAwaitResult,
   RecordStartParams,
@@ -29,7 +29,7 @@ import type {
   RecordStopParams,
   RecordStopResult,
   RpcError,
-  Trace,
+  TraceV2,
 } from "@/transport/types";
 import { handleNavigate } from "./navigation";
 import {
@@ -47,11 +47,11 @@ interface ActiveRecording {
   agentWindowId: number;
   startUrl?: string;
   purpose?: string;
-  steps: DraftTraceStep[];
+  steps: RecordingDraftStep[];
   startedAt: string;
   startedAtMs: number;
-  finishPromise: Promise<Trace>;
-  resolveFinish: (trace: Trace) => void;
+  finishPromise: Promise<TraceV2>;
+  resolveFinish: (trace: TraceV2) => void;
   rejectFinish: (err: Error) => void;
   settled: boolean;
   finishing: boolean;
@@ -154,17 +154,13 @@ async function sendRecordStartWithAck(
   throw lastError ?? new Error("failed to start recording in content script");
 }
 
-function buildTrace(recording: ActiveRecording): Trace {
-  const { pages, steps } = reduceTraceSteps(recording.steps, recording.startUrl);
-  const startUrl = resolveTraceStartUrl(recording.steps, recording.startUrl, pages);
-  return {
+function buildTrace(recording: ActiveRecording): TraceV2 {
+  return buildTraceV2({
+    steps: recording.steps,
+    startedAt: recording.startedAt,
+    ...(recording.startUrl ? { startUrl: recording.startUrl } : {}),
     ...(recording.purpose ? { purpose: recording.purpose } : {}),
-    recorded_at: new Date().toISOString(),
-    started_at: recording.startedAt,
-    entry: { start_url: startUrl },
-    pages,
-    steps,
-  };
+  });
 }
 
 export interface RecordDeps {
@@ -532,7 +528,7 @@ async function finishRecordingByRequest(
   }
 }
 
-async function finishRecording(sessionId: string, deps: RecordDeps): Promise<Trace | null> {
+async function finishRecording(sessionId: string, deps: RecordDeps): Promise<TraceV2 | null> {
   const recording = recordings.get(sessionId);
   if (!recording || recording.settled || recording.finishing) return null;
   recording.finishing = true;
@@ -574,9 +570,9 @@ export async function handleRecordStart(
   // on the destination page can RECORD_QUERY → rearm → show RecordOverlay
   // instead of flashing ControlOverlay ("Agent 正在控制").
   const requestId = makeRequestId(target.tabId);
-  let resolveFinish!: (trace: Trace) => void;
+  let resolveFinish!: (trace: TraceV2) => void;
   let rejectFinish!: (err: Error) => void;
-  const finishPromise = new Promise<Trace>((resolve, reject) => {
+  const finishPromise = new Promise<TraceV2>((resolve, reject) => {
     resolveFinish = resolve;
     rejectFinish = reject;
   });
@@ -785,9 +781,9 @@ export async function handleRecordAwait(
     return { code: "cancelled", message: "record_await aborted" };
   }
 
-  const outcome = await new Promise<{ trace: Trace } | { error: RpcError }>((resolve) => {
+  const outcome = await new Promise<{ trace: TraceV2 } | { error: RpcError }>((resolve) => {
     let settled = false;
-    const finish = (result: { trace: Trace } | { error: RpcError }) => {
+    const finish = (result: { trace: TraceV2 } | { error: RpcError }) => {
       if (settled) return;
       settled = true;
       if (timer) clearTimeout(timer);

apps/extension/src/tools/session.ts

@@ -76,6 +76,7 @@ export interface SessionStopResult {
 }
 
 export interface SessionStopDeps {
+  signal?: AbortSignal;
   cdp?: {
     detachSession(sessionId: string): Promise<void>;
   };
@@ -177,6 +178,9 @@ export async function handleSessionStop(
       message: `session ${params.session_id} unknown`,
     };
   }
+  if (deps.signal?.aborted) {
+    return { code: "cancelled", message: "session_stop aborted before teardown" };
+  }
 
   // Step 1: auto-return borrowed tabs. Iterate over a snapshot of the
   // ids so deletions during iteration do not break the Map iterator.
@@ -187,6 +191,7 @@ export async function handleSessionStop(
     try {
       const tabManagement = {
         ...(deps.tabManagement ?? {}),
+        signal: deps.signal,
         isAgentWindowId:
           deps.tabManagement?.isAgentWindowId ??
           ((windowId: number) => manager.findByWindowId(windowId) !== null),
@@ -214,6 +219,17 @@ export async function handleSessionStop(
     }
   }
 
+  if (deps.signal?.aborted) {
+    const nonCancelFailures = returnFailures?.filter((failure) => failure.code !== "cancelled");
+    if (nonCancelFailures && nonCancelFailures.length > 0) {
+      return {
+        ...(returnedTabIds.length > 0 ? { returned_tab_ids: returnedTabIds } : {}),
+        return_failures: nonCancelFailures,
+      };
+    }
+    return { code: "cancelled", message: "session_stop aborted during tab return" };
+  }
+
   const result: SessionStopResult = {};
   if (returnedTabIds.length > 0) result.returned_tab_ids = returnedTabIds;
   if (returnFailures && returnFailures.length > 0) {
@@ -233,6 +249,10 @@ export async function handleSessionStop(
   // Step 3: detach CDP sessions this session opened (no-op if none).
   await deps.cdp?.detachSession(params.session_id);
 
+  if (deps.signal?.aborted) {
+    return { code: "cancelled", message: "session_stop aborted before window close" };
+  }
+
   // Step 4: close the Agent Window and drop the context.
   await manager.stop(params.session_id);
 

apps/extension/src/tools/shared.ts

@@ -6,7 +6,8 @@
 // exactly the same sandbox + visibility rules as the M6 observation
 // handlers (review parity).
 
-import type { DialogCursor } from "@/browser-driver/chromium-cdp";
+import type { CdpDebuggee, DialogCursor } from "@/browser-driver/chromium-cdp";
+import type { CdpFrameGraph, CdpTarget } from "@/browser-driver/frame-graph";
 import type { SessionContext, SessionManager } from "@/session-manager/manager";
 import { normaliseRef } from "@/session-manager/ref-store";
 import type { ConsoleResult, JavaScriptDialogInfo, RpcError } from "@/transport/types";
@@ -51,9 +52,11 @@ export type { DialogCursor };
  */
 export interface CdpRunner {
   send<T = unknown>(tabId: number, method: string, params?: object): Promise<T>;
+  sendToTarget?<T = unknown>(target: CdpTarget, method: string, params?: object): Promise<T>;
+  getFrameGraph?(tabId: number): Promise<CdpFrameGraph>;
   ensureAttachedToUrl?(tabId: number, expectedUrl: string | undefined): Promise<void>;
   trackSessionTab?(sessionId: string, tabId: number): void;
-  onEvent?(handler: (source: chrome.debugger.Debuggee, method: string, params: unknown) => void): {
+  onEvent?(handler: (source: CdpDebuggee, method: string, params: unknown) => void): {
     dispose(): void;
   };
   dialogCursor?(tabId: number): DialogCursor;
@@ -68,6 +71,25 @@ export interface CdpRunner {
   ): ConsoleResult;
 }
 
+export function sendToCdpTarget<T = unknown>(
+  cdp: CdpRunner,
+  target: CdpTarget,
+  method: string,
+  params?: object,
+): Promise<T> {
+  if (target.sessionId && cdp.sendToTarget) {
+    return cdp.sendToTarget<T>(target, method, params);
+  }
+  return cdp.send<T>(target.tabId, method, params);
+}
+
+export function cdpRunnerForTarget(cdp: CdpRunner, target: CdpTarget): CdpRunner {
+  return {
+    send: <T = unknown>(_tabId: number, method: string, params?: object) =>
+      sendToCdpTarget<T>(cdp, target, method, params),
+  };
+}
+
 export interface BufferedReadBounds {
   since: number | undefined;
   limit: number;

apps/extension/src/tools/snapshot-ref.ts

@@ -1,5 +1,5 @@
 // Snapshot ref resolution — normalise `@eN` / `eN`, look up
-// `backendNodeId` via the session RefStore, and build stable
+// compound CDP node identity via the session RefStore, and build stable
 // `ref_not_found` errors for hard-failure tool paths.
 
 import type { SessionContext } from "@/session-manager/manager";
@@ -10,6 +10,13 @@ import { rpcError } from "./errors";
 export interface SnapshotRefLookup {
   backendNodeId: number;
   refKey: string;
+  frameId?: string;
+  cdpSessionId?: string;
+}
+
+function refEntryForTab(ctx: SessionContext, refKey: string, tabId: number) {
+  const entry = ctx.refStore.resolveEntry(refKey);
+  return entry?.tabId === tabId ? entry : null;
 }
 
 /**
@@ -23,9 +30,14 @@ export function lookupSnapshotRef(
   tabId: number,
 ): SnapshotRefLookup | null {
   const refKey = normaliseRef(ref);
-  const backendNodeId = ctx.refStore.resolve(refKey, { tabId });
-  if (backendNodeId === null) return null;
-  return { backendNodeId, refKey };
+  const entry = refEntryForTab(ctx, refKey, tabId);
+  if (!entry) return null;
+  return {
+    backendNodeId: entry.backendNodeId,
+    refKey,
+    ...(entry.frameId ? { frameId: entry.frameId } : {}),
+    ...(entry.cdpSessionId ? { cdpSessionId: entry.cdpSessionId } : {}),
+  };
 }
 
 /**
@@ -37,7 +49,7 @@ export function resolveSnapshotRef(
   ctx: SessionContext,
   ref: string,
   tabId: number,
-): { backendNodeId: number; refKey: string } | RpcError {
+): SnapshotRefLookup | RpcError {
   const looked = lookupSnapshotRef(ctx, ref, tabId);
   if (looked === null) {
     return rpcError(

apps/extension/src/tools/vom/__tests__/capture.test.ts

@@ -698,7 +698,7 @@ describe("captureViewModel", () => {
     const { nodes } = await captureViewModel(cdp, 4);
     const div = nodes.find((n) => n.backendNodeId === 12);
     expect(div?.localRect?.y).toBe(-200);
-    expect(div?.rect).toMatchObject({ y: -200, h: 800 });
+    expect(div?.rect).toMatchObject({ y: 0, h: 600 });
   });
 
   it("normalizes device-pixel bounds by devicePixelRatio", async () => {
@@ -919,7 +919,7 @@ describe("captureViewModel", () => {
     expect(input?.attrs.type).toBe("text");
     expect(input?.ownerFrameBackendNodeId).toBe(13);
     expect(input?.localRect).toEqual({ x: 0, y: 0, w: 200, h: 40 });
-    expect(input?.rect).toBeNull();
+    expect(input?.rect).toEqual({ x: 100, y: 300, w: 200, h: 40 });
     expect(rootFrameId).toBe("main-frame");
     expect(frameNodes?.get("child-frame")).toBe(subNodes);
     expect(frameOwnerBackendNodeIds?.get("child-frame")).toBe(13);
@@ -1091,10 +1091,10 @@ describe("captureViewModel", () => {
     const input = iframeNodes.get(23)?.find((n) => n.backendNodeId === 31);
 
     expect(nestedIframe?.localRect).toEqual({ x: 5, y: 6, w: 100, h: 80 });
-    expect(nestedIframe?.rect).toBeNull();
+    expect(nestedIframe?.rect).toEqual({ x: 15, y: 26, w: 100, h: 80 });
     expect(input?.ownerFrameBackendNodeId).toBe(23);
     expect(input?.localRect).toEqual({ x: 1, y: 2, w: 40, h: 20 });
-    expect(input?.rect).toBeNull();
+    expect(input?.rect).toEqual({ x: 16, y: 28, w: 40, h: 20 });
   });
 
   it("normalizes bounds then subtracts CSS scroll at dpr>1", async () => {

apps/extension/src/tools/vom/__tests__/frame-capture.test.ts

@@ -3,61 +3,133 @@ import type { CdpRunner } from "../../shared";
 import type { CapturedNode, CapturedViewModel } from "../capture";
 import { captureFrameData } from "../frame-capture";
 
-function node(frameId: string, backendNodeId: number): CapturedNode {
+function ownerNode(backendNodeId: number, x: number): CapturedNode {
   return {
     backendNodeId,
-    parentBackendNodeId: null,
-    frameId,
-    tag: "div",
+    parentBackendNodeId: 1,
+    frameId: "main",
+    ownerFrameBackendNodeId: null,
+    tag: "iframe",
     attrs: {},
-    rect: null,
-    localRect: { x: 0, y: 0, w: 20, h: 20 },
-    paintOrder: 0,
+    rect: { x, y: 100, w: 300, h: 200 },
+    localRect: { x, y: 100, w: 300, h: 200 },
+    paintOrder: 1,
     position: "static",
     pointerEvents: "auto",
   };
 }
 
+function childSnapshot(frameId: string, backendNodeId: number) {
+  const strings = [frameId, "body", "button", "static", "auto", "pointer"];
+  return {
+    strings,
+    documents: [
+      {
+        frameId,
+        nodes: {
+          parentIndex: [-1, 0],
+          nodeName: [1, 2],
+          backendNodeId: [backendNodeId - 1, backendNodeId],
+          attributes: [[], []],
+        },
+        layout: {
+          nodeIndex: [0, 1],
+          styles: [
+            [3, 4, 4],
+            [3, 4, 5],
+          ],
+          bounds: [
+            [0, 0, 300, 200],
+            [10, 20, 100, 40],
+          ],
+          paintOrders: [0, 1],
+        },
+      },
+    ],
+  };
+}
+
 describe("captureFrameData", () => {
-  it("captures AX trees for every same-target frame found in the DOM snapshot", async () => {
+  it("captures and positions multiple OOPIF documents missing from the root snapshot", async () => {
+    const leftOwner = ownerNode(10, 50);
+    const rightOwner = ownerNode(20, 500);
     const captured: CapturedViewModel = {
-      nodes: [node("main", 1)],
+      nodes: [leftOwner, rightOwner],
       viewport: { width: 1000, height: 800 },
-      iframeNodes: new Map([[10, [node("child", 101)]]]),
-      frameNodes: new Map([
-        ["main", [node("main", 1)]],
-        ["child", [node("child", 101)]],
-      ]),
-      frameOwnerBackendNodeIds: new Map([["child", 10]]),
-      frameParentIds: new Map([["child", "main"]]),
+      iframeNodes: new Map(),
+      frameNodes: new Map([["main", [leftOwner, rightOwner]]]),
+      frameOwnerBackendNodeIds: new Map(),
       rootFrameId: "main",
       excludedBackendNodeIds: new Set(),
     };
-    const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
-      if (method === "Accessibility.enable") return {};
-      if (method === "Accessibility.getFullAXTree") {
-        const frameId = (params as { frameId?: string })?.frameId ?? "main";
-        return {
-          nodes: [
-            {
-              nodeId: `${frameId}-root`,
-              frameId,
-              backendDOMNodeId: frameId === "main" ? 1 : 101,
-            },
-          ],
-        };
+    const sendToTarget = vi.fn(async (target, method) => {
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 300, clientHeight: 200, pageX: 0, pageY: 0 } };
       }
+      if (method === "DOMSnapshot.enable" || method === "Accessibility.enable") return {};
+      if (method === "DOMSnapshot.captureSnapshot") {
+        return target.sessionId === "left-session"
+          ? childSnapshot("left", 101)
+          : childSnapshot("right", 201);
+      }
+      if (method === "Accessibility.getFullAXTree") return { nodes: [] };
       throw new Error(`unexpected ${method}`);
     });
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method, params) => {
+        if (method === "Accessibility.enable") return {};
+        if (method === "Accessibility.getFullAXTree") return { nodes: [] };
+        if (method === "DOM.getBoxModel") {
+          const backendNodeId = (params as { backendNodeId?: number })?.backendNodeId;
+          const x = backendNodeId === 10 ? 50 : 500;
+          return { model: { content: [x, 100, x + 300, 100, x + 300, 300, x, 300] } };
+        }
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 1000, clientHeight: 800 } };
+        }
+        throw new Error(`unexpected root ${method}`);
+      }) as CdpRunner["send"],
+      sendToTarget: sendToTarget as unknown as NonNullable<CdpRunner["sendToTarget"]>,
+      getFrameGraph: vi.fn(async () => ({
+        rootFrameId: "main",
+        frames: [
+          { frameId: "main", target: { tabId: 4 } },
+          {
+            frameId: "left",
+            parentFrameId: "main",
+            ownerBackendNodeId: 10,
+            target: { tabId: 4, sessionId: "left-session" },
+          },
+          {
+            frameId: "right",
+            parentFrameId: "main",
+            ownerBackendNodeId: 20,
+            target: { tabId: 4, sessionId: "right-session" },
+          },
+        ],
+      })),
+    };
 
-    const documents = await captureFrameData({ send } as CdpRunner, 4, captured);
+    const trees = await captureFrameData(cdp, 4, captured);
 
-    expect(send).toHaveBeenCalledWith(4, "Accessibility.enable", {});
-    expect(documents.map((document) => document.frameId)).toEqual(["main", "child"]);
-    expect(documents.find((document) => document.frameId === "child")).toMatchObject({
-      parentFrameId: "main",
-      ownerBackendNodeId: 10,
-      axNodes: [{ nodeId: "child-root", frameId: "child", backendDOMNodeId: 101 }],
-    });
+    expect(trees.map((tree) => tree.frameId)).toEqual(["main", "left", "right"]);
+    expect(
+      captured.frameNodes?.get("left")?.find((node) => node.backendNodeId === 101)?.rect,
+    ).toEqual({ x: 60, y: 120, w: 100, h: 40 });
+    expect(
+      captured.frameNodes?.get("right")?.find((node) => node.backendNodeId === 201)?.rect,
+    ).toEqual({ x: 510, y: 120, w: 100, h: 40 });
+    expect(captured.frameOwnerBackendNodeIds).toEqual(
+      new Map([
+        ["left", 10],
+        ["right", 20],
+      ]),
+    );
+    expect(captured.frameParentIds).toEqual(
+      new Map([
+        ["left", "main"],
+        ["right", "main"],
+      ]),
+    );
   });
 });

apps/extension/src/tools/vom/__tests__/frame-document.test.ts

@@ -1,4 +1,5 @@
 import { describe, expect, it } from "vitest";
+import type { CdpFrameGraph } from "@/browser-driver/frame-graph";
 import type { CapturedNode, CapturedViewModel } from "../capture";
 import { buildFrameDocuments, type FrameAxBatch, type FrameOwnedAxNode } from "../frame-document";
 
@@ -9,8 +10,7 @@ function domNode(frameId: string, backendNodeId: number): CapturedNode {
     frameId,
     tag: "div",
     attrs: {},
-    rect: null,
-    localRect: { x: 0, y: 0, w: 20, h: 20 },
+    rect: { x: 0, y: 0, w: 20, h: 20 },
     paintOrder: 0,
     position: "static",
     pointerEvents: "auto",
@@ -30,9 +30,16 @@ function captured(frameNodes: Map<string, CapturedNode[]>): CapturedViewModel {
 
 describe("buildFrameDocuments", () => {
   it("partitions mixed AX results by node ownership and cuts cross-frame parent edges", () => {
+    const graph: CdpFrameGraph = {
+      rootFrameId: "main",
+      frames: [
+        { frameId: "main", target: { tabId: 4 } },
+        { frameId: "child", parentFrameId: "main", target: { tabId: 4 } },
+      ],
+    };
     const batches: FrameAxBatch<FrameOwnedAxNode>[] = [
       {
-        frameId: "main",
+        frame: graph.frames[0],
         nodes: [
           { nodeId: "root", frameId: "main", backendDOMNodeId: 1, childIds: ["h"] },
           {
@@ -48,6 +55,7 @@ describe("buildFrameDocuments", () => {
     ];
 
     const documents = buildFrameDocuments(
+      graph,
       batches,
       captured(
         new Map([
@@ -64,14 +72,28 @@ describe("buildFrameDocuments", () => {
     expect(childNodes.find((node) => node.nodeId === "virtual")?.frameId).toBe("child");
   });
 
-  it("deduplicates overlapping AX results using the strongest ownership", () => {
+  it("deduplicates overlapping same-target AX results using the strongest ownership", () => {
+    const graph: CdpFrameGraph = {
+      rootFrameId: "main",
+      frames: [
+        { frameId: "main", target: { tabId: 4 } },
+        { frameId: "child", parentFrameId: "main", target: { tabId: 4 } },
+      ],
+    };
     const childNode = { nodeId: "shared", backendDOMNodeId: 100 };
     const batches: FrameAxBatch<FrameOwnedAxNode>[] = [
-      { frameId: "main", nodes: [{ ...childNode, frameId: "child" }] },
-      { frameId: "child", nodes: [childNode] },
+      {
+        frame: graph.frames[0],
+        nodes: [{ ...childNode, frameId: "child" }],
+      },
+      {
+        frame: graph.frames[1],
+        nodes: [childNode],
+      },
     ];
 
     const documents = buildFrameDocuments(
+      graph,
       batches,
       captured(
         new Map([
@@ -85,22 +107,64 @@ describe("buildFrameDocuments", () => {
     expect(documents.find((document) => document.frameId === "child")?.axNodes).toHaveLength(1);
   });
 
+  it("uses target-scoped backend ownership when OOPIF backend ids collide", () => {
+    const graph: CdpFrameGraph = {
+      rootFrameId: "main",
+      frames: [
+        { frameId: "main", target: { tabId: 4 } },
+        {
+          frameId: "left",
+          parentFrameId: "main",
+          target: { tabId: 4, sessionId: "left-session" },
+        },
+        {
+          frameId: "right",
+          parentFrameId: "main",
+          target: { tabId: 4, sessionId: "right-session" },
+        },
+      ],
+    };
+    const batches: FrameAxBatch<FrameOwnedAxNode>[] = graph.frames.slice(1).map((frame) => ({
+      frame,
+      nodes: [{ nodeId: `${frame.frameId}-node`, backendDOMNodeId: 7 }],
+    }));
+
+    const documents = buildFrameDocuments(
+      graph,
+      batches,
+      captured(
+        new Map([
+          ["main", []],
+          ["left", [domNode("left", 7)]],
+          ["right", [domNode("right", 7)]],
+        ]),
+      ),
+    );
+
+    expect(documents.find((document) => document.frameId === "left")?.axNodes[0]?.nodeId).toBe(
+      "left-node",
+    );
+    expect(documents.find((document) => document.frameId === "right")?.axNodes[0]?.nodeId).toBe(
+      "right-node",
+    );
+  });
+
   it("uses captured frame parent identity instead of guessing from backend ids", () => {
     const frameNodes = new Map([
       ["main", [domNode("main", 1)]],
       ["left", [domNode("left", 7)]],
-      ["right", [domNode("right", 8)]],
+      ["right", [domNode("right", 7)]],
       ["child", [domNode("child", 9)]],
     ]);
     const capture = captured(frameNodes);
     capture.frameOwnerBackendNodeIds = new Map([["child", 7]]);
     capture.frameParentIds = new Map([["child", "left"]]);
-    const batches = ["main", "left", "right", "child"].map((frameId) => ({
-      frameId,
+    const frames = ["main", "left", "right", "child"].map((frameId) => ({
+      frame: { frameId, target: { tabId: 4 } },
       nodes: [],
     }));
 
-    const documents = buildFrameDocuments(batches, capture);
+    const documents = buildFrameDocuments(null, frames, capture);
 
     expect(documents.find((document) => document.frameId === "child")).toMatchObject({
       parentFrameId: "left",

apps/extension/src/tools/vom/capture.ts

@@ -7,6 +7,7 @@
 import type { Rect, Viewport } from "@browser-skill/vom";
 import { evaluateHoverTrigger } from "@/lib/hover-trigger-policy";
 import { isOverlayHostNode, OVERLAY_HOST_SELECTOR } from "../../lib/overlay-bridge";
+import { childFrameProjection, type GeometryProjection, projectRectToViewport } from "../geometry";
 import type { CdpRunner } from "../shared";
 
 const REQUESTED_STYLES = ["position", "pointer-events", "cursor"] as const;
@@ -22,9 +23,9 @@ export interface CapturedNode {
   ownerFrameBackendNodeId?: number | null;
   tag: string;
   attrs: Record<string, string>;
-  /** Top-level viewport geometry when this node belongs to the root document. */
+  /** Top-level viewport-relative CSS px, clipped to the owning frame viewport. */
   rect: Rect | null;
-  /** Owning document viewport-relative CSS px. */
+  /** Frame-local viewport-relative CSS px before top-level projection. */
   localRect?: Rect | null;
   paintOrder: number;
   position: string;
@@ -317,6 +318,7 @@ interface ParseDocumentResult {
 interface FrameContext {
   frameId?: string;
   ownerFrameBackendNodeId: number | null;
+  projection: GeometryProjection | null;
   scrollX: number;
   scrollY: number;
 }
@@ -869,7 +871,10 @@ function parseDocumentNodes(
           w: b[2] / dpr,
           h: b[3] / dpr,
         };
-        rect = context.ownerFrameBackendNodeId === null ? localRect : null;
+        const bounds = context.projection
+          ? projectRectToViewport(localRect, context.projection)
+          : null;
+        rect = bounds ? { x: bounds.x, y: bounds.y, w: bounds.width, h: bounds.height } : null;
       }
       paintOrder = dl?.paintOrders?.[li] ?? 0;
       const styleRow = dl?.styles?.[li] ?? [];
@@ -939,6 +944,7 @@ function parseChildFrameDocuments(
   strings: string[],
   dpr: number,
   parentDocIndex: number,
+  parentNodes: CapturedNode[],
   parentContext: FrameContext,
   visited = new Set<number>(),
 ): ParseFrameDocumentsResult {
@@ -953,6 +959,7 @@ function parseChildFrameDocuments(
   }
 
   const parentBackendIds = parentDoc?.nodes?.backendNodeId ?? [];
+  const parentNodeByBackendId = new Map(parentNodes.map((node) => [node.backendNodeId, node]));
 
   for (const [nodeArrayIdx, childDocIndex] of cdi) {
     if (visited.has(childDocIndex)) continue;
@@ -960,10 +967,16 @@ function parseChildFrameDocuments(
     if (!childDoc) continue;
     const iframeBackendId = parentBackendIds[nodeArrayIdx];
     if (iframeBackendId === undefined) continue;
+    const iframeNode = parentNodeByBackendId.get(iframeBackendId);
+    const projection =
+      parentContext.projection && iframeNode?.localRect
+        ? childFrameProjection(parentContext.projection, iframeNode.localRect)
+        : null;
 
     const childContext: FrameContext = {
       frameId: snapshotFrameId(childDoc, strings),
       ownerFrameBackendNodeId: iframeBackendId,
+      projection,
       scrollX: childDoc.scrollOffsetX ?? 0,
       scrollY: childDoc.scrollOffsetY ?? 0,
     };
@@ -982,6 +995,7 @@ function parseChildFrameDocuments(
       strings,
       dpr,
       childDocIndex,
+      parsed.nodes,
       childContext,
       nextVisited,
     );
@@ -1042,6 +1056,11 @@ export async function captureViewModel(
   const topContext: FrameContext = {
     frameId: snapshotFrameId(doc0, strings),
     ownerFrameBackendNodeId: null,
+    projection: {
+      sourceClips: [],
+      edges: [],
+      topViewport: viewport,
+    },
     scrollX,
     scrollY,
   };
@@ -1049,7 +1068,7 @@ export async function captureViewModel(
   const nodes = mainParsed.nodes;
   const excludedBackendNodeIds = new Set(mainParsed.excludedBackendNodeIds);
 
-  const frameParsed = parseChildFrameDocuments(documents, strings, dpr, 0, topContext);
+  const frameParsed = parseChildFrameDocuments(documents, strings, dpr, 0, nodes, topContext);
   const iframeNodes = frameParsed.iframeNodes;
   for (const id of frameParsed.excludedBackendNodeIds) {
     excludedBackendNodeIds.add(id);

apps/extension/src/tools/vom/frame-capture.ts

@@ -1,5 +1,8 @@
-import type { CdpRunner } from "../shared";
-import type { CapturedViewModel } from "./capture";
+import type { CdpFrame, CdpFrameGraph } from "@/browser-driver/frame-graph";
+import { resolveFrameProjection } from "../frame-geometry";
+import { type GeometryProjection, projectRectToViewport } from "../geometry";
+import { type CdpRunner, cdpRunnerForTarget, sendToCdpTarget } from "../shared";
+import { type CapturedNode, type CapturedViewModel, captureViewModel } from "./capture";
 import {
   buildFrameDocuments,
   type FrameAxBatch,
@@ -18,39 +21,136 @@ function isAbortError(err: unknown): boolean {
   return err instanceof Error && err.name === "AbortError";
 }
 
-function capturedFrameIds(captured: CapturedViewModel): string[] {
-  const frameIds = new Set<string>();
-  if (captured.rootFrameId) frameIds.add(captured.rootFrameId);
-  for (const frameId of captured.frameNodes?.keys() ?? []) frameIds.add(frameId);
-  if (frameIds.size === 0) frameIds.add("root");
-  return [...frameIds];
+async function discoverFrameGraph(cdp: CdpRunner, tabId: number): Promise<CdpFrameGraph | null> {
+  if (!cdp.getFrameGraph) return null;
+  try {
+    return await cdp.getFrameGraph(tabId);
+  } catch (err) {
+    console.debug("[bsk observation] frame graph capture failed", err);
+    return null;
+  }
+}
+
+function transformFrameNodes(
+  nodes: CapturedNode[],
+  projection: GeometryProjection,
+): CapturedNode[] {
+  return nodes.map((node) => ({
+    ...node,
+    rect: (() => {
+      const bounds = projectRectToViewport(node.rect, projection);
+      return bounds ? { x: bounds.x, y: bounds.y, w: bounds.width, h: bounds.height } : null;
+    })(),
+  }));
+}
+
+function frameOwnerNode(captured: CapturedViewModel, frame: CdpFrame): CapturedNode | undefined {
+  if (frame.ownerBackendNodeId === undefined) return undefined;
+  const parentNodes = frame.parentFrameId
+    ? captured.frameNodes?.get(frame.parentFrameId)
+    : captured.nodes;
+  return parentNodes?.find((node) => node.backendNodeId === frame.ownerBackendNodeId);
+}
+
+async function captureMissingFrameDocuments(
+  cdp: CdpRunner,
+  tabId: number,
+  graph: CdpFrameGraph,
+  captured: CapturedViewModel,
+  signal?: AbortSignal,
+): Promise<void> {
+  if (!captured.frameNodes) captured.frameNodes = new Map();
+  if (!captured.frameOwnerBackendNodeIds) captured.frameOwnerBackendNodeIds = new Map();
+  if (!captured.frameParentIds) captured.frameParentIds = new Map();
+
+  for (const frame of graph.frames) {
+    if (!frame.target.sessionId || captured.frameNodes.has(frame.frameId)) continue;
+    const owner = frameOwnerNode(captured, frame);
+    if (!owner?.rect || frame.ownerBackendNodeId === undefined) continue;
+    try {
+      const child = await captureViewModel(cdpRunnerForTarget(cdp, frame.target), tabId, {
+        signal,
+      });
+      const projection = await resolveFrameProjection(cdp, graph, frame.frameId);
+      if (!projection) continue;
+      const rootFrameId = child.rootFrameId ?? frame.frameId;
+      const childFrames = child.frameNodes ?? new Map<string, CapturedNode[]>();
+      if (!childFrames.has(rootFrameId)) childFrames.set(rootFrameId, child.nodes);
+      if (rootFrameId !== frame.frameId && !childFrames.has(frame.frameId)) {
+        childFrames.set(
+          frame.frameId,
+          child.nodes.map((node) => ({ ...node, frameId: frame.frameId })),
+        );
+      }
+      for (const [childFrameId, nodes] of childFrames) {
+        captured.frameNodes.set(childFrameId, transformFrameNodes(nodes, projection));
+      }
+      captured.iframeNodes.set(
+        frame.ownerBackendNodeId,
+        captured.frameNodes.get(frame.frameId) ?? [],
+      );
+      captured.frameOwnerBackendNodeIds.set(frame.frameId, frame.ownerBackendNodeId);
+      if (frame.parentFrameId) captured.frameParentIds.set(frame.frameId, frame.parentFrameId);
+      for (const [childFrameId, ownerBackendNodeId] of child.frameOwnerBackendNodeIds ?? []) {
+        captured.frameOwnerBackendNodeIds.set(childFrameId, ownerBackendNodeId);
+      }
+      for (const [childFrameId, parentFrameId] of child.frameParentIds ?? []) {
+        captured.frameParentIds.set(childFrameId, parentFrameId);
+      }
+    } catch (err) {
+      if (isAbortError(err)) throw err;
+      console.debug("[bsk observation] child frame DOM capture failed", {
+        frameId: frame.frameId,
+        err,
+      });
+    }
+  }
 }
 
 async function captureAxTrees<T extends FrameAxNode>(
   cdp: CdpRunner,
   tabId: number,
+  discoveredFrames: CdpFrame[],
   captured: CapturedViewModel,
   signal?: AbortSignal,
 ): Promise<FrameAxBatch<T>[]> {
-  const frameIds = capturedFrameIds(captured);
+  let frames = [...discoveredFrames];
+  const capturedFrameIds = [...(captured.frameNodes?.keys() ?? [])];
+  if (frames.length === 0) {
+    const rootFrameId = captured.rootFrameId ?? capturedFrameIds[0] ?? "root";
+    frames = [{ frameId: rootFrameId, target: { tabId } }];
+  }
+  for (const frameId of capturedFrameIds) {
+    if (!frames.some((frame) => frame.frameId === frameId)) {
+      frames.push({ frameId, target: { tabId } });
+    }
+  }
+
   let firstFailure: unknown;
-  await cdp.send(tabId, "Accessibility.enable", {});
   const trees = await Promise.all(
-    frameIds.map(async (frameId): Promise<FrameAxBatch<T>> => {
+    frames.map(async (frame): Promise<FrameAxBatch<T>> => {
       try {
         throwIfAborted(signal);
-        const result = await cdp.send<{ nodes?: T[] }>(
-          tabId,
+        await sendToCdpTarget(cdp, frame.target, "Accessibility.enable", {});
+        const result = await sendToCdpTarget<{ nodes?: T[] }>(
+          cdp,
+          frame.target,
           "Accessibility.getFullAXTree",
-          frameId === "root" ? {} : { frameId },
+          frame.frameId === "root" ? {} : { frameId: frame.frameId },
         );
         throwIfAborted(signal);
-        return { frameId, nodes: result.nodes ?? [] };
+        return {
+          frame,
+          nodes: result.nodes ?? [],
+        };
       } catch (err) {
         if (isAbortError(err)) throw err;
         firstFailure ??= err;
-        console.debug("[bsk observation] frame AX capture failed", { frameId, err });
-        return { frameId, nodes: [] };
+        console.debug("[bsk observation] frame AX capture failed", {
+          frameId: frame.frameId,
+          err,
+        });
+        return { frame, nodes: [] };
       }
     }),
   );
@@ -70,6 +170,10 @@ export async function captureFrameData<T extends FrameAxNode>(
   captured: CapturedViewModel,
   signal?: AbortSignal,
 ): Promise<CapturedFrameDocument<T>[]> {
-  const batches = await captureAxTrees<T>(cdp, tabId, captured, signal);
-  return buildFrameDocuments(batches, captured);
+  const graph = await discoverFrameGraph(cdp, tabId);
+  const frames = graph?.frames ?? [];
+  if (graph) await captureMissingFrameDocuments(cdp, tabId, graph, captured, signal);
+  throwIfAborted(signal);
+  const batches = await captureAxTrees<T>(cdp, tabId, frames, captured, signal);
+  return buildFrameDocuments(graph, batches, captured);
 }

apps/extension/src/tools/vom/frame-document.ts

@@ -1,3 +1,9 @@
+import {
+  type CdpFrame,
+  type CdpFrameGraph,
+  type CdpTarget,
+  cdpTargetKey,
+} from "@/browser-driver/frame-graph";
 import type { CapturedNode, CapturedViewModel } from "./capture";
 
 export interface FrameOwnedAxNode {
@@ -9,14 +15,11 @@ export interface FrameOwnedAxNode {
 }
 
 export interface FrameAxBatch<T extends FrameOwnedAxNode> {
-  frameId: string;
+  frame: CdpFrame;
   nodes: T[];
 }
 
-export interface FrameDocument<T extends FrameOwnedAxNode> {
-  frameId: string;
-  parentFrameId?: string;
-  ownerBackendNodeId?: number;
+export interface FrameDocument<T extends FrameOwnedAxNode> extends CdpFrame {
   contextScopeId: string;
   axNodes: T[];
   domNodes: CapturedNode[];
@@ -29,30 +32,58 @@ interface Ownership {
 
 interface OwnedCandidate<T> {
   node: T;
+  target: CdpTarget;
   ownership: Ownership;
 }
 
-function frameIds<T extends FrameOwnedAxNode>(
+function targetNodeKey(target: CdpTarget, nodeId: string): string {
+  return `${cdpTargetKey(target)}:${nodeId}`;
+}
+
+function targetBackendKey(target: CdpTarget, backendNodeId: number): string {
+  return `${cdpTargetKey(target)}:${backendNodeId}`;
+}
+
+function frameList<T extends FrameOwnedAxNode>(
+  graph: CdpFrameGraph | null,
   batches: FrameAxBatch<T>[],
   captured: CapturedViewModel,
-): string[] {
-  const ids = new Set<string>();
-  if (captured.rootFrameId) ids.add(captured.rootFrameId);
-  for (const frameId of captured.frameNodes?.keys() ?? []) ids.add(frameId);
-  for (const batch of batches) ids.add(batch.frameId);
-  return [...ids];
+): CdpFrame[] {
+  const frames = new Map<string, CdpFrame>();
+  for (const frame of graph?.frames ?? []) frames.set(frame.frameId, frame);
+  for (const batch of batches) {
+    if (!frames.has(batch.frame.frameId)) frames.set(batch.frame.frameId, batch.frame);
+  }
+  for (const frameId of captured.frameNodes?.keys() ?? []) {
+    if (!frames.has(frameId))
+      frames.set(frameId, { frameId, target: { tabId: batches[0]?.frame.target.tabId ?? 0 } });
+  }
+  return [...frames.values()].map((frame) => {
+    const ownerBackendNodeId =
+      frame.ownerBackendNodeId ?? captured.frameOwnerBackendNodeIds?.get(frame.frameId);
+    const parentFrameId = frame.parentFrameId ?? captured.frameParentIds?.get(frame.frameId);
+    return {
+      ...frame,
+      ...(ownerBackendNodeId !== undefined ? { ownerBackendNodeId } : {}),
+      ...(parentFrameId ? { parentFrameId } : {}),
+    };
+  });
 }
 
 export function buildFrameDocuments<T extends FrameOwnedAxNode>(
+  graph: CdpFrameGraph | null,
   batches: FrameAxBatch<T>[],
   captured: CapturedViewModel,
 ): FrameDocument<T>[] {
-  const frames = frameIds(batches, captured);
-  const knownFrames = new Set(frames);
-  const backendOwner = new Map<number, string>();
-  for (const frameId of frames) {
-    for (const node of captured.frameNodes?.get(frameId) ?? []) {
-      backendOwner.set(node.backendNodeId, frameId);
+  const frames = frameList(graph, batches, captured);
+  const frameById = new Map(frames.map((frame) => [frame.frameId, frame]));
+  const rootFrameId = graph?.rootFrameId ?? captured.rootFrameId ?? frames[0]?.frameId;
+  const domNodesForFrame = (frameId: string): CapturedNode[] =>
+    captured.frameNodes?.get(frameId) ?? (frameId === rootFrameId ? captured.nodes : []);
+  const backendOwner = new Map<string, string>();
+  for (const frame of frames) {
+    for (const node of domNodesForFrame(frame.frameId)) {
+      backendOwner.set(targetBackendKey(frame.target, node.backendNodeId), frame.frameId);
     }
   }
 
@@ -64,15 +95,17 @@ export function buildFrameDocuments<T extends FrameOwnedAxNode>(
     const resolveOwnership = (node: T): Ownership => {
       const cached = ownershipByNodeId.get(node.nodeId);
       if (cached) return cached;
-      if (node.frameId && knownFrames.has(node.frameId)) {
+      if (node.frameId && frameById.has(node.frameId)) {
         const ownership = { frameId: node.frameId, strength: 4 };
         ownershipByNodeId.set(node.nodeId, ownership);
         return ownership;
       }
       if (typeof node.backendDOMNodeId === "number") {
-        const owner = backendOwner.get(node.backendDOMNodeId);
-        if (owner) {
-          const ownership = { frameId: owner, strength: 3 };
+        const frameId = backendOwner.get(
+          targetBackendKey(batch.frame.target, node.backendDOMNodeId),
+        );
+        if (frameId) {
+          const ownership = { frameId, strength: 3 };
           ownershipByNodeId.set(node.nodeId, ownership);
           return ownership;
         }
@@ -91,28 +124,32 @@ export function buildFrameDocuments<T extends FrameOwnedAxNode>(
           return ownership;
         }
       }
-      const ownership = { frameId: batch.frameId, strength: 1 };
+      const ownership = { frameId: batch.frame.frameId, strength: 1 };
       ownershipByNodeId.set(node.nodeId, ownership);
       return ownership;
     };
 
     for (const node of batch.nodes) {
       const ownership = resolveOwnership(node);
-      const existing = candidates.get(node.nodeId);
+      const key = targetNodeKey(batch.frame.target, node.nodeId);
+      const existing = candidates.get(key);
       if (!existing || ownership.strength > existing.ownership.strength) {
-        candidates.set(node.nodeId, { node, ownership });
+        candidates.set(key, { node, target: batch.frame.target, ownership });
       }
     }
   }
 
-  const ownershipByNodeId = new Map(
-    [...candidates].map(([nodeId, candidate]) => [nodeId, candidate.ownership.frameId]),
+  const ownershipByTargetNode = new Map(
+    [...candidates].map(([key, candidate]) => [key, candidate.ownership.frameId]),
   );
   const axNodesByFrame = new Map<string, T[]>();
-  for (const { node, ownership } of candidates.values()) {
-    const parentFrameId = node.parentId ? ownershipByNodeId.get(node.parentId) : undefined;
+  for (const candidate of candidates.values()) {
+    const { node, target, ownership } = candidate;
+    const parentFrameId = node.parentId
+      ? ownershipByTargetNode.get(targetNodeKey(target, node.parentId))
+      : undefined;
     const childIds = node.childIds?.filter(
-      (childId) => ownershipByNodeId.get(childId) === ownership.frameId,
+      (childId) => ownershipByTargetNode.get(targetNodeKey(target, childId)) === ownership.frameId,
     );
     const ownedNode = {
       ...node,
@@ -127,16 +164,10 @@ export function buildFrameDocuments<T extends FrameOwnedAxNode>(
     axNodesByFrame.set(ownership.frameId, nodes);
   }
 
-  return frames.map((frameId) => ({
-    frameId,
-    ...(captured.frameParentIds?.get(frameId)
-      ? { parentFrameId: captured.frameParentIds.get(frameId) }
-      : {}),
-    ...(captured.frameOwnerBackendNodeIds?.get(frameId) !== undefined
-      ? { ownerBackendNodeId: captured.frameOwnerBackendNodeIds.get(frameId) }
-      : {}),
-    contextScopeId: frameId,
-    axNodes: axNodesByFrame.get(frameId) ?? [],
-    domNodes: captured.frameNodes?.get(frameId) ?? [],
+  return frames.map((frame) => ({
+    ...frame,
+    contextScopeId: frame.frameId,
+    axNodes: axNodesByFrame.get(frame.frameId) ?? [],
+    domNodes: domNodesForFrame(frame.frameId),
   }));
 }

apps/extension/src/tools/vom/record-safe-observation.ts

@@ -0,0 +1,77 @@
+import type { Rect, RenderedRef, VomResult } from "@browser-skill/vom";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import type { CapturedSurfaceProbe } from "./capture";
+import type { CapturedFrameDocument, FrameAxNode } from "./frame-capture";
+
+/** Frame identity needed to resolve an `@eN` that lives in an iframe. */
+export interface CaptureVomFrame {
+  frameId: string;
+  target: CdpTarget;
+  parentFrameId?: string;
+  ownerBackendNodeId?: number;
+}
+
+/** Allowlisted geometry used to match a recorded action to a rendered ref. */
+export interface CaptureVomMatchNode {
+  frameId: string;
+  backendNodeId: number;
+  tag: string;
+  /** Top-level viewport-relative geometry. */
+  rect: Rect | null;
+  /** Frame-local viewport-relative geometry, when available. */
+  localRect?: Rect | null;
+}
+
+/**
+ * Raw AX/DOM trees are never returned. When `redactValues` is enabled by the
+ * caller, form values in `text` are masked as well.
+ */
+export interface CaptureVomObservationResult {
+  text: string;
+  refs: RenderedRef[];
+  truncated: boolean;
+  rootFrameId: string;
+  frames: CaptureVomFrame[];
+  matchNodes: CaptureVomMatchNode[];
+  surfaceProbes?: CapturedSurfaceProbe[];
+}
+
+function projectFrames(documents: CapturedFrameDocument<FrameAxNode>[]): CaptureVomFrame[] {
+  return documents.map((document) => ({
+    frameId: document.frameId,
+    target: document.target,
+    ...(document.parentFrameId ? { parentFrameId: document.parentFrameId } : {}),
+    ...(document.ownerBackendNodeId !== undefined
+      ? { ownerBackendNodeId: document.ownerBackendNodeId }
+      : {}),
+  }));
+}
+
+function projectMatchNodes(documents: CapturedFrameDocument<FrameAxNode>[]): CaptureVomMatchNode[] {
+  return documents.flatMap((document) =>
+    document.domNodes.map((node) => ({
+      frameId: document.frameId,
+      backendNodeId: node.backendNodeId,
+      tag: node.tag,
+      rect: node.rect,
+      ...(node.localRect !== undefined ? { localRect: node.localRect } : {}),
+    })),
+  );
+}
+
+export function projectRecordSafeObservation(input: {
+  rootFrameId: string;
+  frameDocuments: CapturedFrameDocument<FrameAxNode>[];
+  rendered: VomResult;
+  surfaceProbes?: CapturedSurfaceProbe[];
+}): CaptureVomObservationResult {
+  return {
+    text: input.rendered.text,
+    refs: input.rendered.refs,
+    truncated: input.rendered.truncated,
+    rootFrameId: input.rootFrameId,
+    frames: projectFrames(input.frameDocuments),
+    matchNodes: projectMatchNodes(input.frameDocuments),
+    surfaceProbes: input.surfaceProbes,
+  };
+}

apps/extension/src/transport/types.ts

@@ -657,10 +657,60 @@ export interface EmulateResult {
 }
 
 // --------------------------------------------------------------------------
-// Semantic record payloads — mirror bsk-protocol record.rs (Trace v2)
+// Semantic record payloads mirror the versioned Rust protocol models.
 // --------------------------------------------------------------------------
 
-export interface TargetDescriptor {
+export const TRACE_VERSION_V3 = 3;
+/** Logical v2 identifier. Not a wire field — v2 envelopes omit `version`. */
+export const TRACE_VERSION_V2 = 2;
+export const VOM_FORMAT_VERSION = 1;
+
+export interface TargetDescriptorV3 {
+  ref?: string;
+  role?: string;
+  name?: string;
+  ctx?: string;
+  unmatched?: boolean;
+}
+
+export interface RecorderInfo {
+  bsk: string;
+  vom: number;
+}
+
+export type StopReason = "user_finish" | "cli_stop";
+
+export interface TraceStateV3 {
+  id: string;
+  url: string;
+  title?: string;
+  body: string;
+  truncated?: boolean;
+}
+
+export interface StepResultV3 {
+  state: string;
+}
+
+export interface StepCommonV3 {
+  id: number;
+  state: string;
+  result: StepResultV3;
+}
+
+export type NavigationCause =
+  | "user_typed"
+  | "link"
+  | "form_submit"
+  | "reload"
+  | "history"
+  | "script"
+  | "browser";
+
+export type FillCommit = "enter" | "suggestion" | "blur";
+
+/** Legacy v2 target shape retained for existing record producers. */
+export interface TargetDescriptorV2 {
   role?: string;
   name?: string;
   tag: string;
@@ -673,98 +723,97 @@ export interface TraceEntry {
   start_url: string;
 }
 
-export interface PageRef {
+export interface PageRefV2 {
   id: string;
   url: string;
   title?: string;
 }
 
-export interface SelectedOption {
+export interface SelectedOptionV2 {
   value: string;
   label?: string;
 }
 
-export interface StepEffect {
+export interface StepEffectV2 {
   navigated_to: string;
 }
 
-export interface StepCommon {
+export interface StepCommonV2 {
   id: number;
   page: string;
-  effect?: StepEffect;
+  effect?: StepEffectV2;
 }
 
-/** Capture/buffer draft before v2 reduction. */
-export type DraftTraceStep =
-  | {
-      op: "click";
-      target: TargetDescriptor;
-      navigated_to?: string;
-      page_url?: string;
-    }
-  | {
-      op: "hover";
-      target: TargetDescriptor;
-      page_url?: string;
-    }
-  | {
-      op: "fill";
-      target: TargetDescriptor;
-      value: string;
-      redacted?: boolean;
-      page_url?: string;
-    }
-  | {
-      op: "press";
-      key: string;
-      target?: TargetDescriptor;
-      modifiers?: KeyModifier[];
-      navigated_to?: string;
-      page_url?: string;
-    }
-  | {
-      op: "select";
-      target: TargetDescriptor;
-      values: string[];
-      labels?: string[];
-      navigated_to?: string;
-      page_url?: string;
-    }
-  | {
-      op: "navigate";
-      url: string;
-      page_url?: string;
-    };
-
 /** Exported record-only step (trace v2). */
-export type Step =
-  | ({ op: "navigate" } & StepCommon & { to: string })
-  | ({ op: "click" } & StepCommon & { target: TargetDescriptor })
-  | ({ op: "hover" } & StepCommon & { target: TargetDescriptor })
-  | ({ op: "fill" } & StepCommon & {
-        target: TargetDescriptor;
+export type StepV2 =
+  | ({ op: "navigate" } & StepCommonV2 & { to: string })
+  | ({ op: "click" } & StepCommonV2 & { target: TargetDescriptorV2 })
+  | ({ op: "hover" } & StepCommonV2 & { target: TargetDescriptorV2 })
+  | ({ op: "fill" } & StepCommonV2 & {
+        target: TargetDescriptorV2;
         value: string;
         redacted?: boolean;
       })
-  | ({ op: "select" } & StepCommon & {
-        target: TargetDescriptor;
-        selection: SelectedOption[];
+  | ({ op: "select" } & StepCommonV2 & {
+        target: TargetDescriptorV2;
+        selection: SelectedOptionV2[];
       })
-  | ({ op: "press" } & StepCommon & {
+  | ({ op: "press" } & StepCommonV2 & {
         key: string;
         modifiers?: KeyModifier[];
-        target?: TargetDescriptor;
+        target?: TargetDescriptorV2;
       });
 
-export interface Trace {
+export interface TraceV2 {
   recorded_at: string;
   started_at?: string;
   purpose?: string;
   entry: TraceEntry;
-  pages: PageRef[];
-  steps: Step[];
+  pages: PageRefV2[];
+  steps: StepV2[];
 }
 
+export interface SelectedOptionV3 {
+  value: string;
+  label?: string;
+}
+
+export type StepV3 =
+  | ({ op: "navigate" } & StepCommonV3 & { to: string; cause: NavigationCause })
+  | ({ op: "click" } & StepCommonV3 & { target: TargetDescriptorV3 })
+  | ({ op: "hover" } & StepCommonV3 & { target: TargetDescriptorV3 })
+  | ({ op: "fill" } & StepCommonV3 & {
+        target: TargetDescriptorV3;
+        value: string;
+        commit: FillCommit;
+        redacted?: boolean;
+      })
+  | ({ op: "select" } & StepCommonV3 & {
+        target: TargetDescriptorV3;
+        selection?: SelectedOptionV3[];
+      })
+  | ({ op: "press" } & StepCommonV3 & {
+        key: string;
+        modifiers?: KeyModifier[];
+        target?: TargetDescriptorV3;
+      })
+  | ({ op: "scroll" } & StepCommonV3);
+
+export interface TraceV3 {
+  version: typeof TRACE_VERSION_V3;
+  recorded_at: string;
+  started_at?: string;
+  purpose?: string;
+  stopped_by: StopReason;
+  entry: TraceEntry;
+  recorder: RecorderInfo;
+  states: TraceStateV3[];
+  steps: StepV3[];
+}
+
+export type RecordedTrace = TraceV2 | TraceV3;
+export type RecordedStep = StepV2 | StepV3;
+
 export interface RecordStartParams {
   session_id: string;
   tab_id?: number;
@@ -782,7 +831,7 @@ export interface RecordStopParams {
 }
 
 export interface RecordStopResult {
-  trace: Trace;
+  trace: RecordedTrace;
 }
 
 export interface RecordAwaitParams {
@@ -791,5 +840,5 @@ export interface RecordAwaitParams {
 }
 
 export interface RecordAwaitResult {
-  trace: Trace;
+  trace: RecordedTrace;
 }

apps/extension/wxt.config.ts

@@ -25,10 +25,8 @@ export default defineConfig({
     name: "BrowserSkill",
     description:
       "Let AI agents use your logged-in browser in a separate Agent Window—without interrupting your work. Powered by the bsk CLI.",
-    // Chrome 116 is the first version where WebSocket activity resets the
-    // service-worker idle timer, which the 20s heartbeat relies on to
-    // keep the daemon link alive.
-    minimum_chrome_version: "116",
+    // Flat debugger sessions are required to address out-of-process iframes.
+    minimum_chrome_version: "125",
     permissions: [
       "alarms",
       "debugger",

crates/bsk-cli/src/cli/doctor.rs

@@ -18,6 +18,12 @@ use crate::daemon::state::PROTOCOL_VERSION;
 const EXTENSION_STORE_URL: &str =
     "https://chromewebstore.google.com/detail/hhcmgoofomhgciiibhipgmgkgnoenaoi";
 
+/// Edge Add-ons listing for the browser-skill extension.
+const EXTENSION_STORE_URL_EDGE: &str = "https://microsoftedge.microsoft.com/addons/detail/browserskill/emacgiaaaiojkkpkddmmdfhmokgmnikg";
+
+/// Store listings highlighted in repair hints, in the order they appear.
+const EXTENSION_STORE_URLS: [&str; 2] = [EXTENSION_STORE_URL, EXTENSION_STORE_URL_EDGE];
+
 /// Status of a single doctor check. `Ok` / `Fail` are the legacy two
 /// states; `NotApplicable` (review M2) is reported as "N/A" in human
 /// output and as `"status": "na"` in `--json` output, so a check that
@@ -420,7 +426,10 @@ fn check_extension_connected(status: Option<&StatusResult>) -> CheckResult {
         CheckResult::fail(
             name,
             "0 browsers connected",
-            format!("install the extension from {EXTENSION_STORE_URL} and load it in Chromium"),
+            format!(
+                "install the extension from {EXTENSION_STORE_URL} (Chrome) \
+                 or {EXTENSION_STORE_URL_EDGE} (Edge) and load it in the browser"
+            ),
         )
     }
 }
@@ -428,17 +437,14 @@ fn check_extension_connected(status: Option<&StatusResult>) -> CheckResult {
 /// Highlight known URLs in repair hints for terminal output. Plain
 /// text is preserved in `--json` and in stored [`CheckResult::hint`].
 fn style_hint(hint: &str) -> String {
-    if !hint.contains(EXTENSION_STORE_URL) {
-        return hint.to_string();
+    let mut styled = hint.to_string();
+    for url in EXTENSION_STORE_URLS {
+        if !styled.contains(url) {
+            continue;
+        }
+        styled = styled.replace(url, &style(url).cyan().bold().underlined().to_string());
     }
-    hint.replace(
-        EXTENSION_STORE_URL,
-        &style(EXTENSION_STORE_URL)
-            .cyan()
-            .bold()
-            .underlined()
-            .to_string(),
-    )
+    styled
 }
 
 fn render_human(checks: &[CheckResult]) {
@@ -504,6 +510,26 @@ mod m2_tests {
             hint.contains(EXTENSION_STORE_URL),
             "hint should include Chrome Web Store URL: {hint}"
         );
+        assert!(
+            hint.contains(EXTENSION_STORE_URL_EDGE),
+            "hint should include Edge Add-ons URL: {hint}"
+        );
+    }
+
+    #[test]
+    fn style_hint_preserves_every_store_url() {
+        let hint = check_extension_connected(Some(&fake_status(Vec::new(), Vec::new())))
+            .hint
+            .expect("extension disconnected should include a hint");
+        let styled = style_hint(&hint);
+        // Whether or not the terminal accepts colors, styling must never drop or
+        // mangle a URL the user has to click.
+        for url in EXTENSION_STORE_URLS {
+            assert!(
+                styled.contains(url),
+                "styled hint should still contain {url}: {styled}"
+            );
+        }
     }
 
     #[test]

crates/bsk-cli/src/cli/record.rs

@@ -8,7 +8,7 @@ use anyhow::Context;
 use bsk_protocol::Method;
 use bsk_protocol::tools::{
     RecordAwaitParams, RecordAwaitResult, RecordStartParams, RecordStartResult, RecordStopParams,
-    RecordStopResult, Trace,
+    RecordStopResult, RecordedTrace,
 };
 use clap::{Args, Subcommand};
 
@@ -190,7 +190,7 @@ fn record_await_ipc_timeout(timeout_ms: u32) -> Duration {
         .unwrap_or(Duration::from_secs(u64::from(timeout_ms / 1_000) + 15))
 }
 
-fn write_trace_file(output: &PathBuf, trace: &Trace) -> Result<(), CliError> {
+fn write_trace_file(output: &PathBuf, trace: &RecordedTrace) -> Result<(), CliError> {
     let json = serde_json::to_string_pretty(trace)
         .context("serialize trace JSON")
         .map_err(CliError::Local)?;
@@ -207,7 +207,7 @@ fn write_trace_file(output: &PathBuf, trace: &Trace) -> Result<(), CliError> {
     Ok(())
 }
 
-fn render_finish(trace: &Trace, output: &PathBuf, format: Format) -> Result<(), CliError> {
+fn render_finish(trace: &RecordedTrace, output: &PathBuf, format: Format) -> Result<(), CliError> {
     match format {
         Format::Json => {
             println!(
@@ -221,7 +221,11 @@ fn render_finish(trace: &Trace, output: &PathBuf, format: Format) -> Result<(),
             );
         }
         Format::Human => {
-            println!("saved {} steps to {}", trace.steps.len(), output.display());
+            let step_count = match trace {
+                RecordedTrace::V2(trace) => trace.steps.len(),
+                RecordedTrace::V3(trace) => trace.steps.len(),
+            };
+            println!("saved {step_count} steps to {}", output.display());
         }
     }
     Ok(())

crates/bsk-cli/src/daemon/ipc.rs

@@ -206,15 +206,15 @@ pub fn full_handler(status: DaemonStatus, state: Arc<DaemonState>) -> RpcHandler
                     Ok(v) => ResponseBody::Ok(v),
                     Err(e) => ResponseBody::Err(e),
                 },
-                Method::SessionStart => match handle_session_start(&state, params).await {
+                Method::SessionStart => match handle_session_start(&state, rpc_id, params).await {
                     Ok(v) => ResponseBody::Ok(v),
                     Err(e) => ResponseBody::Err(e),
                 },
-                Method::SessionStop => match handle_session_stop(&state, params).await {
+                Method::SessionStop => match handle_session_stop(&state, rpc_id, params).await {
                     Ok(v) => ResponseBody::Ok(v),
                     Err(e) => ResponseBody::Err(e),
                 },
-                Method::SessionStopAll => match handle_session_stop_all(&state).await {
+                Method::SessionStopAll => match handle_session_stop_all_rpc(&state, rpc_id).await {
                     Ok(v) => ResponseBody::Ok(v),
                     Err(e) => ResponseBody::Err(e),
                 },
@@ -434,8 +434,9 @@ async fn handle_wait_ms(
 /// cancellation surfaces (M10.2 + review C2):
 ///
 /// 1. [`AbortRegistry`] — answers daemon-local cancellable runners
-///    (currently `tool.wait_ms`). If a token is registered we trip it
-///    and stop.
+///    (`tool.wait_ms` and `session.*` lifecycle calls). If a token is
+///    registered we trip it and stop. Lifecycle handlers forward their
+///    own WS cancel after preserving request-before-cancel ordering.
 /// 2. [`super::inflight::ToolInflightRegistry`] — every IPC-tracked
 ///    `tool.*` RPC, registered the moment the IPC handler accepts the
 ///    request. Trips the entry's cancel token regardless of whether
@@ -634,7 +635,20 @@ fn clamp_browser_wait(wait_ms: Option<u64>) -> Option<Duration> {
     ))
 }
 
-async fn handle_session_start(state: &Arc<DaemonState>, params: Value) -> Result<Value, RpcError> {
+async fn handle_session_start(
+    state: &Arc<DaemonState>,
+    rpc_id: RpcId,
+    params: Value,
+) -> Result<Value, RpcError> {
+    let abort_guard = state
+        .abort_registry
+        .register(rpc_id)
+        .map_err(|err| RpcError {
+            code: ErrorCode::ProtocolError,
+            message: format!("session.start cancellation registration failed: {err:?}"),
+            data: None,
+        })?;
+    let cancel = abort_guard.token().clone();
     let params: CliSessionStartParams = if params.is_null() {
         CliSessionStartParams {
             browser_instance_id: None,
@@ -673,6 +687,7 @@ async fn handle_session_start(state: &Arc<DaemonState>, params: Value) -> Result
         },
         state.config.extension_connect_wait,
         DEFAULT_RPC_TIMEOUT,
+        Some(cancel),
     )
     .await
     {
@@ -696,6 +711,8 @@ fn map_start_error(err: StartSessionError) -> RpcError {
         StartSessionError::AmbiguousBrowserLabel { .. } => ErrorCode::InvalidParams,
         StartSessionError::IdExhausted => ErrorCode::ProtocolError,
         StartSessionError::Timeout => ErrorCode::Timeout,
+        StartSessionError::Cancelled => ErrorCode::Cancelled,
+        StartSessionError::CleanupFailed { .. } => ErrorCode::ProtocolError,
         StartSessionError::TransportClosed => ErrorCode::ProtocolError,
         StartSessionError::ExtensionError(inner) => inner.code,
     };
@@ -711,6 +728,16 @@ fn map_start_error(err: StartSessionError) -> RpcError {
             "label": label,
             "instance_ids": instance_ids,
         })),
+        StartSessionError::CleanupFailed {
+            session_id,
+            agent_window_id,
+            ..
+        } => Some(serde_json::json!({
+            "reason": "cleanup_failed",
+            "session_id": session_id.0,
+            "agent_window_id": agent_window_id,
+        })),
+        StartSessionError::ExtensionError(inner) => inner.data.clone(),
         _ => None,
     };
     RpcError {
@@ -720,7 +747,20 @@ fn map_start_error(err: StartSessionError) -> RpcError {
     }
 }
 
-async fn handle_session_stop(state: &Arc<DaemonState>, params: Value) -> Result<Value, RpcError> {
+async fn handle_session_stop(
+    state: &Arc<DaemonState>,
+    rpc_id: RpcId,
+    params: Value,
+) -> Result<Value, RpcError> {
+    let abort_guard = state
+        .abort_registry
+        .register(rpc_id)
+        .map_err(|err| RpcError {
+            code: ErrorCode::ProtocolError,
+            message: format!("session.stop cancellation registration failed: {err:?}"),
+            data: None,
+        })?;
+    let cancel = abort_guard.token().clone();
     let params: CliSessionStopParams = if params.is_null() {
         CliSessionStopParams {
             session_id: None,
@@ -734,7 +774,7 @@ async fn handle_session_stop(state: &Arc<DaemonState>, params: Value) -> Result<
         })?
     };
     if params.all {
-        return handle_session_stop_all(state).await;
+        return handle_session_stop_all(state, Some(cancel)).await;
     }
     let session_id = match params.session_id {
         Some(s) => SessionId(s),
@@ -753,6 +793,7 @@ async fn handle_session_stop(state: &Arc<DaemonState>, params: Value) -> Result<
         &state.session_interrupts,
         &session_id,
         DEFAULT_SESSION_STOP_TIMEOUT,
+        Some(cancel),
     )
     .await
     {
@@ -804,7 +845,25 @@ fn map_stop_error(err: StopSessionError) -> RpcError {
     }
 }
 
-async fn handle_session_stop_all(state: &Arc<DaemonState>) -> Result<Value, RpcError> {
+async fn handle_session_stop_all_rpc(
+    state: &Arc<DaemonState>,
+    rpc_id: RpcId,
+) -> Result<Value, RpcError> {
+    let abort_guard = state
+        .abort_registry
+        .register(rpc_id)
+        .map_err(|err| RpcError {
+            code: ErrorCode::ProtocolError,
+            message: format!("session.stop_all cancellation registration failed: {err:?}"),
+            data: None,
+        })?;
+    handle_session_stop_all(state, Some(abort_guard.token().clone())).await
+}
+
+async fn handle_session_stop_all(
+    state: &Arc<DaemonState>,
+    cancel: Option<super::abort::AbortToken>,
+) -> Result<Value, RpcError> {
     let ids: Vec<SessionId> = state
         .sessions
         .snapshot()
@@ -816,6 +875,16 @@ async fn handle_session_stop_all(state: &Arc<DaemonState>) -> Result<Value, RpcE
     let mut returned_tab_ids = Vec::new();
     let mut return_failures = Vec::new();
     for id in ids {
+        if cancel
+            .as_ref()
+            .is_some_and(super::abort::AbortToken::is_cancelled)
+        {
+            return Err(RpcError {
+                code: ErrorCode::Cancelled,
+                message: "session.stop_all was cancelled".into(),
+                data: None,
+            });
+        }
         match stop_session(
             &state.browsers,
             &state.sessions,
@@ -823,6 +892,7 @@ async fn handle_session_stop_all(state: &Arc<DaemonState>) -> Result<Value, RpcE
             &state.session_interrupts,
             &id,
             DEFAULT_SESSION_STOP_TIMEOUT,
+            cancel.clone(),
         )
         .await
         {
@@ -848,6 +918,15 @@ async fn handle_session_stop_all(state: &Arc<DaemonState>) -> Result<Value, RpcE
                 returned_tab_ids.extend(stop.returned_tab_ids);
                 return_failures.extend(stop.return_failures);
             }
+            Err(err)
+                if matches!(
+                    &err,
+                    StopSessionError::ExtensionError(inner)
+                        if inner.code == ErrorCode::Cancelled
+                ) =>
+            {
+                return Err(map_stop_error(err));
+            }
             Err(err) => {
                 debug!(session = %id, ?err, "session.stop_all: failure (continuing)");
                 let rpc = map_stop_error(err);

crates/bsk-cli/src/daemon/queue.rs

@@ -43,6 +43,7 @@ use serde_json::Value;
 use tokio::sync::{mpsc, oneshot};
 use tracing::{debug, warn};
 
+use super::abort::AbortToken;
 use super::browsers::BrowserRegistry;
 use super::inflight::{PromoteOutcome, ToolInflightEntry};
 use super::sessions::{SessionId, SessionRegistry};
@@ -83,6 +84,14 @@ pub struct ToolJob {
     /// IPC request id (e.g. `session.stop`'s queued teardown call —
     /// those already carry their own bespoke retry / abort path).
     pub inflight: Option<Arc<ToolInflightEntry>>,
+    /// Cancellation token for session-lifecycle work registered in the
+    /// daemon-local abort registry. Unlike `inflight`, lifecycle callers
+    /// forward their own WS cancel after the request has been queued.
+    pub lifecycle_cancel: Option<AbortToken>,
+    /// How long cancellation keeps the worker busy while the extension
+    /// finishes compensation. Session teardown uses its full RPC budget
+    /// so daemon state is reconciled even after the CLI exits.
+    pub cancel_cleanup_timeout: Duration,
     /// Owning session — used by `ToolInflightRegistry::cancel_session`
     /// to drain queued jobs that have not yet been promoted to
     /// "forwarded". Worker callers also have access to it via the
@@ -322,6 +331,8 @@ impl ToolQueueRegistry {
             timeout,
             false,
             inflight,
+            None,
+            CANCEL_CLEANUP_TIMEOUT,
         )
         .await;
         // A long-running request may outlive the idle threshold. Touching
@@ -360,6 +371,8 @@ impl ToolQueueRegistry {
             timeout,
             respond: respond_tx,
             inflight,
+            lifecycle_cancel: None,
+            cancel_cleanup_timeout: CANCEL_CLEANUP_TIMEOUT,
             session_id: sid.clone(),
         };
         match forward_one(sid, &self.browsers, &self.sessions, &job).await {
@@ -378,6 +391,7 @@ impl ToolQueueRegistry {
         method: Method,
         params: Value,
         timeout: Duration,
+        cancel: Option<AbortToken>,
     ) -> Result<Value, DispatchError> {
         let (sender, state) = {
             let mut guard = self.queues.lock().expect("tool queue registry poisoned");
@@ -404,6 +418,8 @@ impl ToolQueueRegistry {
             timeout,
             true,
             None,
+            cancel,
+            timeout,
         )
         .await
     }
@@ -419,6 +435,8 @@ async fn dispatch_with_sender(
     timeout: Duration,
     wait_for_capacity: bool,
     inflight: Option<Arc<ToolInflightEntry>>,
+    lifecycle_cancel: Option<AbortToken>,
+    cancel_cleanup_timeout: Duration,
 ) -> Result<Value, DispatchError> {
     let (respond_tx, respond_rx) = oneshot::channel();
     let job = ToolJob {
@@ -427,8 +445,11 @@ async fn dispatch_with_sender(
         timeout,
         respond: respond_tx,
         inflight,
+        lifecycle_cancel,
+        cancel_cleanup_timeout,
         session_id,
     };
+    let lifecycle_cancellable = job.lifecycle_cancel.is_some();
     if wait_for_capacity {
         let waited = tokio::time::timeout(
             timeout.saturating_add(Duration::from_secs(1)),
@@ -453,8 +474,15 @@ async fn dispatch_with_sender(
             mpsc::error::TrySendError::Closed(_) => DispatchError::QueueClosed,
         });
     }
-    let waited =
-        tokio::time::timeout(timeout.saturating_add(Duration::from_secs(1)), respond_rx).await;
+    let mut response_timeout = timeout.saturating_add(Duration::from_secs(1));
+    if lifecycle_cancellable {
+        // A lifecycle cancel can arrive at the original RPC deadline and
+        // intentionally keeps the worker alive while extension cleanup
+        // settles. Do not let this outer waiter abandon that reconciliation
+        // early, which could reopen a daemon session whose window is gone.
+        response_timeout = response_timeout.saturating_add(cancel_cleanup_timeout);
+    }
+    let waited = tokio::time::timeout(response_timeout, respond_rx).await;
     match waited {
         Ok(Ok(Ok(v))) => Ok(v),
         Ok(Ok(Err(rpc))) => Err(DispatchError::Rpc(rpc)),
@@ -492,11 +520,17 @@ async fn forward_one(
     // / browser resolution work, and before any WS frame leaves the
     // daemon (review C2). We keep the `tokio::select!` later so
     // cancels arriving mid-WS-hop also unblock the worker.
-    if let Some(entry) = job.inflight.as_ref()
-        && entry.is_cancelled()
+    if job
+        .inflight
+        .as_ref()
+        .is_some_and(|entry| entry.is_cancelled())
+        || job
+            .lifecycle_cancel
+            .as_ref()
+            .is_some_and(AbortToken::is_cancelled)
     {
         return Err(cancelled_error(
-            Some(entry),
+            job.inflight.as_deref(),
             "tool dispatch cancelled before forwarding",
         ));
     }
@@ -560,11 +594,20 @@ async fn forward_one(
             }
         }
         None => {
-            // Daemon-internal callers (e.g. queued session.stop drain)
-            // don't carry an inflight entry; they cannot be cancelled
-            // through the IPC `cancel` surface, so a plain sink send
-            // is sufficient and keeps the existing transport-error
-            // behaviour.
+            // Daemon-internal callers do not carry a tool-inflight entry.
+            // Session lifecycle jobs instead use the abort-registry token
+            // below; other internal callers keep the plain send path.
+            if job
+                .lifecycle_cancel
+                .as_ref()
+                .is_some_and(AbortToken::is_cancelled)
+            {
+                client.pending.lock().unwrap().cancel(&rpc_id);
+                return Err(cancelled_error(
+                    None,
+                    "session lifecycle cancelled before forwarding",
+                ));
+            }
             if client.sink.send(request).is_err() {
                 client.pending.lock().unwrap().cancel(&rpc_id);
                 return Err(RpcError {
@@ -573,19 +616,45 @@ async fn forward_one(
                     data: None,
                 });
             }
-            None
+            job.lifecycle_cancel.clone()
         }
     };
+    let forward_lifecycle_cancel = || {
+        if job.lifecycle_cancel.is_none() {
+            return;
+        }
+        let cancel = Frame::Request(RequestFrame {
+            id: format!("cancel-{rpc_id}"),
+            method: Method::Cancel,
+            params: Some(serde_json::json!({ "rpc_id": rpc_id })),
+        });
+        if let Err(err) = client.sink.send(cancel) {
+            warn!(%rpc_id, ?err, "failed to forward session lifecycle cancel");
+        }
+    };
+    let on_abort: Option<&(dyn Fn() + Sync)> = job
+        .lifecycle_cancel
+        .as_ref()
+        .map(|_| &forward_lifecycle_cancel as &(dyn Fn() + Sync));
     let waited = await_with_optional_cancel(
         job.timeout,
-        CANCEL_CLEANUP_TIMEOUT,
+        job.cancel_cleanup_timeout,
         waiter,
         cancel_token.as_ref(),
+        on_abort,
     )
     .await;
     let response = match waited {
         WaitOutcome::Response(resp) => resp,
         WaitOutcome::CancelledAfterResponse(resp) => {
+            if job.method == Method::ToolSessionStop
+                && let ResponseBody::Ok(value) = resp.body
+            {
+                // Teardown crossed its final irreversible boundary before
+                // the cancel landed. Commit the real extension result so the
+                // daemon does not retain a session whose window is gone.
+                return Ok(value);
+            }
             // Cancellation wins the external verdict, but only after the
             // extension's original RPC has settled. Preserve any non-cancel
             // error so compensation failures remain explicit instead of
@@ -600,13 +669,33 @@ async fn forward_one(
                 "tool dispatch cancelled after extension cleanup",
             ));
         }
+        WaitOutcome::TimedOutAfterResponse(resp) => match resp.body {
+            ResponseBody::Ok(value) if job.method == Method::ToolSessionStop => {
+                // The close crossed its irreversible boundary during the
+                // timeout cleanup grace. Reconcile daemon state instead of
+                // reopening a session whose window is already gone.
+                return Ok(value);
+            }
+            ResponseBody::Err(err)
+                if !matches!(err.code, ErrorCode::Cancelled | ErrorCode::UserAborted) =>
+            {
+                return Err(err);
+            }
+            _ => {
+                return Err(RpcError {
+                    code: ErrorCode::Timeout,
+                    message: format!("tool RPC timed out after {:?}", job.timeout),
+                    data: None,
+                });
+            }
+        },
         WaitOutcome::CleanupTimeout => {
             client.pending.lock().unwrap().cancel(&rpc_id);
             return Err(RpcError {
                 code: ErrorCode::Timeout,
                 message: format!(
                     "cancelled tool did not finish cleanup within {:?}",
-                    CANCEL_CLEANUP_TIMEOUT
+                    job.cancel_cleanup_timeout
                 ),
                 data: Some(serde_json::json!({ "reason": "cancel_cleanup_timeout" })),
             });
@@ -638,6 +727,7 @@ async fn forward_one(
 enum WaitOutcome {
     Response(bsk_protocol::ResponseFrame),
     CancelledAfterResponse(bsk_protocol::ResponseFrame),
+    TimedOutAfterResponse(bsk_protocol::ResponseFrame),
     CleanupTimeout,
     WaiterClosed,
     Timeout,
@@ -648,6 +738,7 @@ async fn await_with_optional_cancel(
     cleanup_timeout: Duration,
     mut waiter: oneshot::Receiver<bsk_protocol::ResponseFrame>,
     cancel: Option<&super::abort::AbortToken>,
+    on_abort: Option<&(dyn Fn() + Sync)>,
 ) -> WaitOutcome {
     match cancel {
         Some(token) => {
@@ -659,6 +750,9 @@ async fn await_with_optional_cancel(
                 // after compensation or the cleanup deadline expires.
                 biased;
                 _ = token.cancelled() => {
+                    if let Some(on_abort) = on_abort {
+                        on_abort();
+                    }
                     match tokio::time::timeout(cleanup_timeout, &mut waiter).await {
                         Ok(Ok(resp)) => WaitOutcome::CancelledAfterResponse(resp),
                         Ok(Err(_)) => WaitOutcome::WaiterClosed,
@@ -669,7 +763,17 @@ async fn await_with_optional_cancel(
                     Ok(resp) => WaitOutcome::Response(resp),
                     Err(_) => WaitOutcome::WaiterClosed,
                 },
-                _ = &mut deadline => WaitOutcome::Timeout,
+                _ = &mut deadline => {
+                    let Some(on_abort) = on_abort else {
+                        return WaitOutcome::Timeout;
+                    };
+                    on_abort();
+                    match tokio::time::timeout(cleanup_timeout, &mut waiter).await {
+                        Ok(Ok(resp)) => WaitOutcome::TimedOutAfterResponse(resp),
+                        Ok(Err(_)) => WaitOutcome::WaiterClosed,
+                        Err(_) => WaitOutcome::CleanupTimeout,
+                    }
+                },
             }
         }
         None => match tokio::time::timeout(timeout, &mut waiter).await {
@@ -759,6 +863,7 @@ mod await_with_optional_cancel_tests {
             Duration::from_secs(1),
             rx,
             Some(&token),
+            None,
         )
         .await;
         assert!(
@@ -781,6 +886,7 @@ mod await_with_optional_cancel_tests {
             Duration::from_secs(1),
             rx,
             Some(&token),
+            None,
         )
         .await;
         match outcome {
@@ -795,9 +901,14 @@ mod await_with_optional_cancel_tests {
     async fn no_cancel_token_still_returns_response() {
         let (tx, rx) = oneshot::channel();
         tx.send(dummy_response()).unwrap();
-        let outcome =
-            await_with_optional_cancel(Duration::from_secs(10), Duration::from_secs(1), rx, None)
-                .await;
+        let outcome = await_with_optional_cancel(
+            Duration::from_secs(10),
+            Duration::from_secs(1),
+            rx,
+            None,
+            None,
+        )
+        .await;
         assert!(matches!(outcome, WaitOutcome::Response(_)));
     }
 
@@ -812,6 +923,7 @@ mod await_with_optional_cancel_tests {
                 Duration::from_secs(1),
                 rx,
                 Some(&token),
+                None,
             )
             .await
         });
@@ -835,10 +947,37 @@ mod await_with_optional_cancel_tests {
             Duration::from_millis(10),
             rx,
             Some(&token),
+            None,
         )
         .await;
         assert!(matches!(outcome, WaitOutcome::CleanupTimeout));
     }
+
+    #[tokio::test]
+    async fn lifecycle_timeout_forwards_abort_and_waits_for_cleanup_response() {
+        use std::sync::atomic::{AtomicBool, Ordering};
+
+        let token = AbortToken::new();
+        let (tx, rx) = oneshot::channel();
+        let abort_forwarded = AtomicBool::new(false);
+        let forward_abort = || abort_forwarded.store(true, Ordering::SeqCst);
+        tokio::spawn(async move {
+            tokio::time::sleep(Duration::from_millis(20)).await;
+            tx.send(dummy_response()).unwrap();
+        });
+
+        let outcome = await_with_optional_cancel(
+            Duration::from_millis(5),
+            Duration::from_millis(100),
+            rx,
+            Some(&token),
+            Some(&forward_abort),
+        )
+        .await;
+
+        assert!(abort_forwarded.load(Ordering::SeqCst));
+        assert!(matches!(outcome, WaitOutcome::TimedOutAfterResponse(_)));
+    }
 }
 
 #[cfg(test)]
@@ -901,6 +1040,8 @@ mod tool_job_session_id_tests {
             timeout: Duration::from_secs(1),
             respond: tx,
             inflight: None,
+            lifecycle_cancel: None,
+            cancel_cleanup_timeout: CANCEL_CLEANUP_TIMEOUT,
             session_id: SessionId("sess-A".into()),
         };
         assert_eq!(job.session_id.0, "sess-A");

crates/bsk-cli/src/daemon/sessions.rs

@@ -12,13 +12,14 @@ use bsk_protocol::system::{BrowserStatusEntry, SessionStatusEntry};
 use bsk_protocol::tools::{
     SessionStartParams, SessionStartResult, SessionStopParams, SessionStopResult,
 };
-use bsk_protocol::{Frame, RequestFrame, ResponseBody, RpcError, RpcId};
+use bsk_protocol::{ErrorCode, Frame, Method, RequestFrame, ResponseBody, RpcError, RpcId};
 use rand::Rng;
 use serde::{Deserialize, Serialize};
 use tokio::time::{Duration, timeout};
 
+use super::abort::AbortToken;
 use super::browsers::{BrowserClient, BrowserId, BrowserRegistry, SelectError};
-use super::queue::{DispatchError, ToolQueueRegistry};
+use super::queue::{CANCEL_CLEANUP_TIMEOUT, DispatchError, ToolQueueRegistry};
 use super::session_interrupt::SessionInterruptRegistry;
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize, Deserialize)]
@@ -339,6 +340,14 @@ pub enum StartSessionError {
     IdExhausted,
     #[error("session creation timed out waiting for extension")]
     Timeout,
+    #[error("session creation was cancelled")]
+    Cancelled,
+    #[error("session creation cancellation cleanup failed for {session_id}: {message}")]
+    CleanupFailed {
+        session_id: SessionId,
+        agent_window_id: Option<i64>,
+        message: String,
+    },
     #[error("extension rejected tool.session_start: {0:?}")]
     ExtensionError(RpcError),
     #[error("transport closed while waiting for extension response")]
@@ -354,6 +363,8 @@ impl StartSessionError {
             StartSessionError::AmbiguousBrowserLabel { .. } => "invalid_params",
             StartSessionError::IdExhausted => "protocol_error",
             StartSessionError::Timeout => "timeout",
+            StartSessionError::Cancelled => "cancelled",
+            StartSessionError::CleanupFailed { .. } => "protocol_error",
             StartSessionError::TransportClosed => "protocol_error",
             StartSessionError::ExtensionError(err) => match err.code {
                 bsk_protocol::ErrorCode::Timeout => "timeout",
@@ -407,6 +418,7 @@ pub struct AgentWindowOptions {
 /// On success the matching per-session dispatch queue (M6.5,
 /// design §5) is also spawned so that subsequent `tool.*` RPCs serialise
 /// against this session's Agent Window / ref-store.
+#[allow(clippy::too_many_arguments)]
 pub async fn start_session(
     registry: &Arc<BrowserRegistry>,
     sessions: &Arc<SessionRegistry>,
@@ -415,24 +427,32 @@ pub async fn start_session(
     window: AgentWindowOptions,
     connect_wait: Duration,
     timeout_dur: Duration,
+    cancel: Option<AbortToken>,
 ) -> Result<Session, StartSessionError> {
-    let client: Arc<BrowserClient> = registry
-        .select_with_connect_wait(requested, connect_wait)
-        .await
-        .map_err(|e| match e {
-            SelectError::NoBrowserConnected => StartSessionError::NoBrowserConnected,
-            SelectError::MultipleBrowsersOnline => StartSessionError::MultipleBrowsersOnline {
-                browsers: snapshot_status_entries(registry, sessions),
-            },
-            SelectError::NotFound => StartSessionError::BrowserNotFound,
-            SelectError::AmbiguousLabel {
-                label,
-                instance_ids,
-            } => StartSessionError::AmbiguousBrowserLabel {
-                label,
-                instance_ids,
-            },
-        })?;
+    let selection = registry.select_with_connect_wait(requested, connect_wait);
+    tokio::pin!(selection);
+    let selected = match cancel.as_ref() {
+        Some(token) => tokio::select! {
+            biased;
+            _ = token.cancelled() => return Err(StartSessionError::Cancelled),
+            selected = &mut selection => selected,
+        },
+        None => selection.await,
+    };
+    let client: Arc<BrowserClient> = selected.map_err(|e| match e {
+        SelectError::NoBrowserConnected => StartSessionError::NoBrowserConnected,
+        SelectError::MultipleBrowsersOnline => StartSessionError::MultipleBrowsersOnline {
+            browsers: snapshot_status_entries(registry, sessions),
+        },
+        SelectError::NotFound => StartSessionError::BrowserNotFound,
+        SelectError::AmbiguousLabel {
+            label,
+            instance_ids,
+        } => StartSessionError::AmbiguousBrowserLabel {
+            label,
+            instance_ids,
+        },
+    })?;
     let session_id = sessions
         .reserve_id(client.id.clone(), SESSION_ID_MAX_RESERVE_ATTEMPTS, now_ms)
         .ok_or(StartSessionError::IdExhausted)?;
@@ -453,22 +473,71 @@ pub async fn start_session(
         let mut pending = client.pending.lock().unwrap();
         pending.register(rpc_id.clone())
     };
+    if cancel.as_ref().is_some_and(AbortToken::is_cancelled) {
+        sessions.cancel_reservation(&session_id);
+        client.pending.lock().unwrap().cancel(&rpc_id);
+        return Err(StartSessionError::Cancelled);
+    }
     if client.sink.send(Frame::Request(request)).is_err() {
         sessions.cancel_reservation(&session_id);
         client.pending.lock().unwrap().cancel(&rpc_id);
         return Err(StartSessionError::TransportClosed);
     }
-    let response = match timeout(timeout_dur, waiter).await {
-        Ok(Ok(resp)) => resp,
-        Ok(Err(_)) => {
+    let mut waiter = waiter;
+    enum StartWaitOutcome {
+        Response(bsk_protocol::ResponseFrame),
+        WaiterClosed,
+        Cancelled,
+        Timeout,
+    }
+    let wait_outcome = match cancel.as_ref() {
+        Some(token) => {
+            let deadline = tokio::time::sleep(timeout_dur);
+            tokio::pin!(deadline);
+            tokio::select! {
+                biased;
+                _ = token.cancelled() => StartWaitOutcome::Cancelled,
+                response = &mut waiter => match response {
+                    Ok(response) => StartWaitOutcome::Response(response),
+                    Err(_) => StartWaitOutcome::WaiterClosed,
+                },
+                _ = &mut deadline => StartWaitOutcome::Timeout,
+            }
+        }
+        None => match timeout(timeout_dur, &mut waiter).await {
+            Ok(Ok(response)) => StartWaitOutcome::Response(response),
+            Ok(Err(_)) => StartWaitOutcome::WaiterClosed,
+            Err(_) => StartWaitOutcome::Timeout,
+        },
+    };
+    let response = match wait_outcome {
+        StartWaitOutcome::Response(response) => response,
+        StartWaitOutcome::WaiterClosed => {
             sessions.cancel_reservation(&session_id);
             client.pending.lock().unwrap().cancel(&rpc_id);
             return Err(StartSessionError::TransportClosed);
         }
-        Err(_) => {
-            sessions.cancel_reservation(&session_id);
-            client.pending.lock().unwrap().cancel(&rpc_id);
-            return Err(StartSessionError::Timeout);
+        StartWaitOutcome::Cancelled => {
+            return Err(finish_aborted_start(
+                &client,
+                sessions,
+                &session_id,
+                &rpc_id,
+                waiter,
+                StartAbortReason::Cancelled,
+            )
+            .await);
+        }
+        StartWaitOutcome::Timeout => {
+            return Err(finish_aborted_start(
+                &client,
+                sessions,
+                &session_id,
+                &rpc_id,
+                waiter,
+                StartAbortReason::Timeout,
+            )
+            .await);
         }
     };
     let agent_window_id = match response.body {
@@ -504,6 +573,124 @@ pub async fn start_session(
     Ok(session)
 }
 
+#[derive(Clone, Copy)]
+enum StartAbortReason {
+    Cancelled,
+    Timeout,
+}
+
+impl StartAbortReason {
+    fn error(self) -> StartSessionError {
+        match self {
+            Self::Cancelled => StartSessionError::Cancelled,
+            Self::Timeout => StartSessionError::Timeout,
+        }
+    }
+}
+
+async fn finish_aborted_start(
+    client: &Arc<BrowserClient>,
+    sessions: &Arc<SessionRegistry>,
+    session_id: &SessionId,
+    rpc_id: &RpcId,
+    mut waiter: tokio::sync::oneshot::Receiver<bsk_protocol::ResponseFrame>,
+    reason: StartAbortReason,
+) -> StartSessionError {
+    sessions.cancel_reservation(session_id);
+    let cancel = Frame::Request(RequestFrame {
+        id: format!("cancel-{rpc_id}"),
+        method: Method::Cancel,
+        params: Some(serde_json::json!({ "rpc_id": rpc_id })),
+    });
+    if client.sink.send(cancel).is_err() {
+        client.pending.lock().unwrap().cancel(rpc_id);
+        return StartSessionError::TransportClosed;
+    }
+
+    match timeout(CANCEL_CLEANUP_TIMEOUT, &mut waiter).await {
+        Ok(Ok(response)) => match response.body {
+            ResponseBody::Err(err)
+                if matches!(err.code, ErrorCode::Cancelled | ErrorCode::UserAborted) =>
+            {
+                reason.error()
+            }
+            ResponseBody::Err(err) => StartSessionError::ExtensionError(err),
+            ResponseBody::Ok(value) => {
+                let agent_window_id = serde_json::from_value::<SessionStartResult>(value)
+                    .ok()
+                    .and_then(|result| result.agent_window_id);
+                match rollback_extension_session(client, session_id).await {
+                    Ok(()) => reason.error(),
+                    Err(message) => StartSessionError::CleanupFailed {
+                        session_id: session_id.clone(),
+                        agent_window_id,
+                        message,
+                    },
+                }
+            }
+        },
+        Ok(Err(_)) => {
+            client.pending.lock().unwrap().cancel(rpc_id);
+            StartSessionError::TransportClosed
+        }
+        Err(_) => {
+            // The cancel frame is already queued behind session_start. Even
+            // if chrome.windows.create is still blocked, the extension will
+            // observe the aborted signal and compensate before replying.
+            client.pending.lock().unwrap().cancel(rpc_id);
+            reason.error()
+        }
+    }
+}
+
+async fn rollback_extension_session(
+    client: &Arc<BrowserClient>,
+    session_id: &SessionId,
+) -> Result<(), String> {
+    let rollback_id = next_rpc_id("sess-start-rollback");
+    let waiter = {
+        let mut pending = client.pending.lock().unwrap();
+        pending.register(rollback_id.clone())
+    };
+    let request = RequestFrame {
+        id: rollback_id.clone(),
+        method: Method::ToolSessionStop,
+        params: Some(
+            serde_json::to_value(SessionStopParams {
+                session_id: session_id.0.clone(),
+            })
+            .expect("serialize session_start rollback params"),
+        ),
+    };
+    if client.sink.send(Frame::Request(request)).is_err() {
+        client.pending.lock().unwrap().cancel(&rollback_id);
+        return Err("browser disconnected before rollback was queued".into());
+    }
+    let response = match timeout(CANCEL_CLEANUP_TIMEOUT, waiter).await {
+        Ok(Ok(response)) => response,
+        Ok(Err(_)) => return Err("browser disconnected during rollback".into()),
+        Err(_) => {
+            client.pending.lock().unwrap().cancel(&rollback_id);
+            return Err(format!(
+                "extension did not finish rollback within {CANCEL_CLEANUP_TIMEOUT:?}"
+            ));
+        }
+    };
+    match response.body {
+        ResponseBody::Ok(value) => {
+            let result: SessionStopResult = serde_json::from_value(value)
+                .map_err(|err| format!("invalid rollback response: {err}"))?;
+            if result.return_failures.is_empty() {
+                Ok(())
+            } else {
+                Err("rollback reported borrowed-tab return failures".into())
+            }
+        }
+        ResponseBody::Err(err) if err.code == ErrorCode::NotFound => Ok(()),
+        ResponseBody::Err(err) => Err(format!("rollback failed: {} ({:?})", err.message, err.code)),
+    }
+}
+
 /// Tear down a single session id (round-trips `tool.session_stop` to the
 /// owning extension and unregisters on success). Also tears down the
 /// per-session dispatch queue so the worker task exits.
@@ -514,6 +701,7 @@ pub async fn stop_session(
     interrupts: &Arc<SessionInterruptRegistry>,
     session_id: &SessionId,
     timeout_dur: Duration,
+    cancel: Option<AbortToken>,
 ) -> Result<SessionStopResult, StopSessionError> {
     let session = sessions.get(session_id).ok_or(StopSessionError::NotFound)?;
     if registry.get(&session.browser_id).is_none() {
@@ -524,12 +712,17 @@ pub async fn stop_session(
         session_id: session_id.0.clone(),
     })
     .unwrap();
+    // Internal callers (idle reaping and shutdown) do not have a CLI-owned
+    // token, but still need timeout-driven WS cancellation so a late window
+    // close cannot leave daemon state pointing at a vanished session.
+    let lifecycle_cancel = Some(cancel.unwrap_or_default());
     match queues
         .dispatch_after_closing(
             session_id,
             bsk_protocol::Method::ToolSessionStop,
             params,
             timeout_dur,
+            lifecycle_cancel,
         )
         .await
     {
@@ -567,6 +760,10 @@ pub async fn stop_session(
                 drop_session_local(queues, interrupts, session_id);
                 return Ok(SessionStopResult::default());
             }
+            if err.code == bsk_protocol::ErrorCode::Timeout {
+                queues.reopen(session_id);
+                return Err(StopSessionError::Timeout);
+            }
             queues.reopen(session_id);
             Err(StopSessionError::ExtensionError(err))
         }

crates/bsk-cli/src/daemon/start.rs

@@ -15,7 +15,6 @@ use std::net::{IpAddr, Ipv4Addr, SocketAddr};
 use std::path::Path;
 use std::sync::Arc;
 use std::sync::Mutex;
-use std::sync::atomic::{AtomicUsize, Ordering};
 use std::time::{Duration, Instant};
 
 use anyhow::{Context, Result};
@@ -291,8 +290,7 @@ pub fn run_foreground(cfg: DaemonConfig) -> Result<()> {
         });
 
         let started_at = Instant::now();
-        let activity: Arc<Mutex<Instant>> = Arc::new(Mutex::new(started_at));
-        let active_ipc_connections = Arc::new(AtomicUsize::new(0));
+        let activity = Arc::new(Mutex::new(IpcActivityState::new(started_at)));
         let (ipc_shutdown_tx, ipc_shutdown_rx) = tokio::sync::oneshot::channel::<()>();
         let status = ipc::DaemonStatus {
             started_at,
@@ -314,18 +312,14 @@ pub fn run_foreground(cfg: DaemonConfig) -> Result<()> {
             let handler = handler.clone();
             let ipc_open = {
                 let activity = activity.clone();
-                let active = active_ipc_connections.clone();
                 move || {
-                    active.fetch_add(1, Ordering::SeqCst);
-                    record_activity(&activity);
+                    record_ipc_open(&activity);
                 }
             };
             let ipc_close = {
                 let activity = activity.clone();
-                let active = active_ipc_connections.clone();
                 move || {
-                    active.fetch_sub(1, Ordering::SeqCst);
-                    record_activity(&activity);
+                    record_ipc_close(&activity);
                 }
             };
             tokio::spawn(ipc::serve(
@@ -344,7 +338,6 @@ pub fn run_foreground(cfg: DaemonConfig) -> Result<()> {
         let idle_task = {
             let activity = activity.clone();
             let state = Arc::clone(&state);
-            let active_ipc_connections = active_ipc_connections.clone();
             let daemon_idle = cfg.daemon_idle;
             tokio::spawn(async move {
                 let tick = (daemon_idle / 4).max(Duration::from_millis(250));
@@ -352,22 +345,19 @@ pub fn run_foreground(cfg: DaemonConfig) -> Result<()> {
                 ticker.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Delay);
                 loop {
                     ticker.tick().await;
-                    let last = match activity.lock() {
-                        Ok(a) => *a,
-                        Err(p) => *p.into_inner(),
-                    };
-                    if last.elapsed() < daemon_idle {
+                    let ipc_is_idle =
+                        lock_activity(&activity).should_exit_for_idle(Instant::now(), daemon_idle);
+                    if !ipc_is_idle {
                         continue;
                     }
-                    // Bridge from M2/M3 (which only knew about connection
-                    // counts) to M4/M5 (browser + session registries):
-                    // hold the daemon alive while any IPC client is
-                    // connected, any browser is paired, or any session
-                    // is live (design §3.2).
-                    if active_ipc_connections.load(Ordering::SeqCst) > 0
-                        || !state.browsers.is_empty()
-                        || !state.sessions.is_empty()
-                    {
+                    // IPC liveness (open-connection count + idle window) is already
+                    // enforced above by `should_exit_for_idle`, which reads
+                    // `IpcActivityState` under one lock and returns true only when
+                    // there are zero connections AND the idle interval has elapsed.
+                    // Here we additionally hold the daemon alive while any browser
+                    // is paired or any session is live (design §3.2, M4/M5
+                    // registries).
+                    if !state.browsers.is_empty() || !state.sessions.is_empty() {
                         continue;
                     }
                     info!(
@@ -491,6 +481,7 @@ pub(crate) fn spawn_session_idle_reaper(state: Arc<DaemonState>) -> tokio::task:
                     &state.session_interrupts,
                     &session_id,
                     Duration::from_secs(10),
+                    None,
                 )
                 .await
                 {
@@ -681,10 +672,55 @@ fn restart_start_args(cfg: &DaemonConfig) -> StartArgs {
     }
 }
 
-fn record_activity(activity: &Arc<Mutex<Instant>>) {
-    if let Ok(mut a) = activity.lock() {
-        *a = Instant::now();
+#[derive(Debug)]
+struct IpcActivityState {
+    last_activity: Instant,
+    active_connections: usize,
+}
+
+impl IpcActivityState {
+    fn new(now: Instant) -> Self {
+        Self {
+            last_activity: now,
+            active_connections: 0,
+        }
     }
+
+    fn touch(&mut self, now: Instant) {
+        self.last_activity = now;
+    }
+
+    fn opened(&mut self, now: Instant) {
+        self.active_connections = self.active_connections.saturating_add(1);
+        self.last_activity = now;
+    }
+
+    fn closed(&mut self, now: Instant) {
+        self.active_connections = self.active_connections.saturating_sub(1);
+        self.last_activity = now;
+    }
+
+    fn should_exit_for_idle(&self, now: Instant, idle: Duration) -> bool {
+        self.active_connections == 0 && now.saturating_duration_since(self.last_activity) >= idle
+    }
+}
+
+fn lock_activity(
+    activity: &Arc<Mutex<IpcActivityState>>,
+) -> std::sync::MutexGuard<'_, IpcActivityState> {
+    activity.lock().unwrap_or_else(|poison| poison.into_inner())
+}
+
+fn record_activity(activity: &Arc<Mutex<IpcActivityState>>) {
+    lock_activity(activity).touch(Instant::now());
+}
+
+fn record_ipc_open(activity: &Arc<Mutex<IpcActivityState>>) {
+    lock_activity(activity).opened(Instant::now());
+}
+
+fn record_ipc_close(activity: &Arc<Mutex<IpcActivityState>>) {
+    lock_activity(activity).closed(Instant::now());
 }
 
 /// Initialise tracing for the daemon: write a daily-rotated file in
@@ -1067,4 +1103,37 @@ mod tests {
         assert_eq!(args.session_idle, Some(Duration::from_secs(11)));
         assert_eq!(args.daemon_idle, Some(Duration::from_secs(22)));
     }
+
+    #[test]
+    fn ipc_close_restarts_the_idle_window_atomically() {
+        let started = Instant::now();
+        let idle = Duration::from_secs(10);
+        let mut activity = IpcActivityState::new(started);
+
+        activity.opened(started);
+        let closed_at = started + Duration::from_secs(30);
+        assert!(
+            !activity.should_exit_for_idle(closed_at, idle),
+            "an open IPC connection must hold the daemon alive"
+        );
+
+        activity.closed(closed_at);
+        assert_eq!(activity.active_connections, 0);
+        assert_eq!(activity.last_activity, closed_at);
+        assert!(!activity.should_exit_for_idle(closed_at, idle));
+        assert!(!activity.should_exit_for_idle(closed_at + idle - Duration::from_millis(1), idle));
+        assert!(activity.should_exit_for_idle(closed_at + idle, idle));
+    }
+
+    #[test]
+    fn ipc_activity_keeps_the_daemon_alive_until_a_full_idle_interval_passes() {
+        let started = Instant::now();
+        let idle = Duration::from_secs(10);
+        let mut activity = IpcActivityState::new(started);
+        let request_at = started + Duration::from_secs(20);
+
+        activity.touch(request_at);
+        assert!(!activity.should_exit_for_idle(request_at + Duration::from_secs(9), idle));
+        assert!(activity.should_exit_for_idle(request_at + idle, idle));
+    }
 }

crates/bsk-cli/src/daemon/state.rs

@@ -34,8 +34,8 @@ pub struct DaemonState {
     /// `stop_session` / browser disconnect.
     pub tool_queues: Arc<ToolQueueRegistry>,
     /// Per-rpc-id cancellation tokens for daemon-side long-runners
-    /// (M9.3 — currently only `tool.wait_ms`). The CLI's `cancel
-    /// { rpc_id }` consults this registry first.
+    /// (`tool.wait_ms` plus `session.*` lifecycle calls). The CLI's
+    /// `cancel { rpc_id }` consults this registry first.
     pub abort_registry: Arc<AbortRegistry>,
     /// Tracks `tool.*` RPCs that have been forwarded to an extension
     /// over WS but have not yet received a response. Indexed by the

crates/bsk-cli/tests/per_session_queue.rs

@@ -325,6 +325,7 @@ async fn session_stop_fast_fails_while_tool_is_in_flight() {
         &state.session_interrupts,
         &sid,
         Duration::from_secs(5),
+        None,
     )
     .await;
     assert!(
@@ -366,6 +367,7 @@ async fn session_stop_fast_fails_while_tool_is_in_flight() {
         &state.session_interrupts,
         &sid,
         Duration::from_secs(5),
+        None,
     )
     .await
     .expect("session.stop ok after tool completes");

crates/bsk-cli/tests/sessions_ipc.rs

@@ -10,9 +10,14 @@ use std::time::Duration;
 
 use bsk::daemon::{self, DaemonConfig};
 use bsk::ipc_client::IpcClient;
+use bsk_protocol::cancel::{CancelParams, CancelResult};
 use bsk_protocol::system::{HandshakeParams, HandshakeResult, StatusResult};
-use bsk_protocol::tools::{SessionStartParams, SessionStartResult, SessionStopParams};
-use bsk_protocol::{BrowserPeerInfo, Frame, Method, RequestFrame, ResponseBody, ResponseFrame};
+use bsk_protocol::tools::{
+    SessionStartParams, SessionStartResult, SessionStopParams, SessionStopResult,
+};
+use bsk_protocol::{
+    BrowserPeerInfo, ErrorCode, Frame, Method, RequestFrame, ResponseBody, ResponseFrame, RpcError,
+};
 use futures_util::{SinkExt, StreamExt};
 use rand::Rng;
 use tokio_tungstenite::tungstenite::handshake::client::generate_key;
@@ -23,6 +28,9 @@ use support::{wait_for_browser_count, wait_for_no_sessions};
 
 const TEST_EXT_ID: &str = "abcdefghijklmnopabcdefghijklmnop";
 
+type TestWs =
+    tokio_tungstenite::WebSocketStream<tokio_tungstenite::MaybeTlsStream<tokio::net::TcpStream>>;
+
 fn tempfile_path(prefix: &str) -> PathBuf {
     let mut p = std::env::temp_dir();
     let mut rng = rand::thread_rng();
@@ -56,9 +64,7 @@ async fn spawn_daemon_with_session_idle(session_idle: Duration) -> (daemon::Daem
     (handle, sock)
 }
 
-async fn connect_ext(
-    addr: std::net::SocketAddr,
-) -> tokio_tungstenite::WebSocketStream<tokio_tungstenite::MaybeTlsStream<tokio::net::TcpStream>> {
+async fn connect_ext(addr: std::net::SocketAddr) -> TestWs {
     let origin = format!("chrome-extension://{TEST_EXT_ID}");
     let url = format!("ws://{addr}/");
     let req = Request::builder()
@@ -76,11 +82,7 @@ async fn connect_ext(
     ws
 }
 
-async fn handshake_as_ext(
-    ws: &mut tokio_tungstenite::WebSocketStream<
-        tokio_tungstenite::MaybeTlsStream<tokio::net::TcpStream>,
-    >,
-) -> HandshakeResult {
+async fn handshake_as_ext(ws: &mut TestWs) -> HandshakeResult {
     let params = HandshakeParams {
         client: "browser-skill-extension".into(),
         version: "0.1.0-dev.0".parse().unwrap(),
@@ -114,6 +116,128 @@ async fn handshake_as_ext(
     }
 }
 
+async fn next_extension_request(ws: &mut TestWs) -> RequestFrame {
+    loop {
+        let message = ws.next().await.expect("daemon closed websocket").unwrap();
+        match message {
+            Message::Text(text) => match serde_json::from_str::<Frame>(&text).unwrap() {
+                Frame::Request(request) => return request,
+                Frame::Response(_) | Frame::Event(_) => continue,
+            },
+            Message::Ping(payload) => ws.send(Message::Pong(payload)).await.unwrap(),
+            Message::Close(_) => panic!("daemon closed websocket before sending request"),
+            _ => {}
+        }
+    }
+}
+
+async fn send_extension_response(ws: &mut TestWs, response: ResponseFrame) {
+    ws.send(Message::Text(serde_json::to_string(&response).unwrap()))
+        .await
+        .unwrap();
+}
+
+async fn acknowledge_extension_cancel(ws: &mut TestWs, cancel: RequestFrame, target_rpc_id: &str) {
+    assert_eq!(cancel.method, Method::Cancel);
+    let params: CancelParams = serde_json::from_value(cancel.params.unwrap()).unwrap();
+    assert_eq!(params.rpc_id, target_rpc_id);
+    send_extension_response(
+        ws,
+        ResponseFrame {
+            id: cancel.id,
+            body: ResponseBody::Ok(serde_json::to_value(CancelResult { cancelled: true }).unwrap()),
+        },
+    )
+    .await;
+}
+
+async fn respond_to_aborted_start(
+    ws: &mut TestWs,
+    start_seen: Option<tokio::sync::oneshot::Sender<()>>,
+    agent_window_id: i64,
+) {
+    let start = next_extension_request(ws).await;
+    assert_eq!(start.method, Method::ToolSessionStart);
+    let params: SessionStartParams = serde_json::from_value(start.params.clone().unwrap()).unwrap();
+    if let Some(start_seen) = start_seen {
+        start_seen.send(()).unwrap();
+    }
+
+    let cancel = next_extension_request(ws).await;
+    acknowledge_extension_cancel(ws, cancel, &start.id).await;
+
+    // Model the hardest race: chrome.windows.create completed just as
+    // cancellation arrived, so the extension's original call succeeds.
+    send_extension_response(
+        ws,
+        ResponseFrame {
+            id: start.id,
+            body: ResponseBody::Ok(
+                serde_json::to_value(SessionStartResult {
+                    agent_window_id: Some(agent_window_id),
+                })
+                .unwrap(),
+            ),
+        },
+    )
+    .await;
+
+    let rollback = next_extension_request(ws).await;
+    assert_eq!(rollback.method, Method::ToolSessionStop);
+    let rollback_params: SessionStopParams =
+        serde_json::from_value(rollback.params.unwrap()).unwrap();
+    assert_eq!(rollback_params.session_id, params.session_id);
+    send_extension_response(
+        ws,
+        ResponseFrame {
+            id: rollback.id,
+            body: ResponseBody::Ok(serde_json::to_value(SessionStopResult::default()).unwrap()),
+        },
+    )
+    .await;
+}
+
+async fn respond_to_aborted_stop(
+    ws: &mut TestWs,
+    stop_seen: Option<tokio::sync::oneshot::Sender<()>>,
+) {
+    let start = next_extension_request(ws).await;
+    assert_eq!(start.method, Method::ToolSessionStart);
+    send_extension_response(
+        ws,
+        ResponseFrame {
+            id: start.id,
+            body: ResponseBody::Ok(
+                serde_json::to_value(SessionStartResult {
+                    agent_window_id: Some(4242),
+                })
+                .unwrap(),
+            ),
+        },
+    )
+    .await;
+
+    let stop = next_extension_request(ws).await;
+    assert_eq!(stop.method, Method::ToolSessionStop);
+    if let Some(stop_seen) = stop_seen {
+        stop_seen.send(()).unwrap();
+    }
+    let cancel = next_extension_request(ws).await;
+    acknowledge_extension_cancel(ws, cancel, &stop.id).await;
+    send_extension_response(
+        ws,
+        ResponseFrame {
+            id: stop.id,
+            body: ResponseBody::Err(RpcError {
+                code: ErrorCode::Cancelled,
+                message: "session_stop aborted before window close".into(),
+                data: None,
+            }),
+        },
+    )
+    .await;
+}
+
 #[tokio::test]
 async fn session_start_stop_round_trip_via_ipc() {
     let (handle, sock) = spawn_daemon().await;
@@ -250,6 +374,240 @@ async fn session_start_stop_round_trip_via_ipc() {
     handle.shutdown().await;
 }
 
+#[tokio::test]
+async fn cancelling_session_start_rolls_back_a_late_extension_success() {
+    const START_RPC_ID: &str = "session-start-cancel";
+
+    let (handle, sock) = spawn_daemon().await;
+    let mut ws = connect_ext(handle.ws_addr()).await;
+    let _ = handshake_as_ext(&mut ws).await;
+    let (start_seen_tx, start_seen_rx) = tokio::sync::oneshot::channel();
+    let (release_tx, release_rx) = tokio::sync::oneshot::channel();
+
+    let responder = tokio::spawn(async move {
+        respond_to_aborted_start(&mut ws, Some(start_seen_tx), 4242).await;
+        let _ = release_rx.await;
+    });
+
+    let mut start_ipc = IpcClient::connect(&sock).await.unwrap();
+    let start_call = tokio::spawn(async move {
+        let outcome: Result<serde_json::Value, RpcError> = start_ipc
+            .call_with_id(
+                START_RPC_ID.to_string(),
+                Method::SessionStart,
+                Some(serde_json::json!({ "focused": false })),
+                Duration::from_secs(5),
+            )
+            .await
+            .unwrap();
+        outcome
+    });
+
+    start_seen_rx.await.unwrap();
+    let mut cancel_ipc = IpcClient::connect(&sock).await.unwrap();
+    let cancel: CancelResult = cancel_ipc
+        .call(
+            "cancel-start",
+            Method::Cancel,
+            Some(CancelParams {
+                rpc_id: START_RPC_ID.to_string(),
+            }),
+            Duration::from_secs(2),
+        )
+        .await
+        .unwrap()
+        .unwrap();
+    assert!(cancel.cancelled);
+
+    let start_error = start_call.await.unwrap().unwrap_err();
+    assert_eq!(start_error.code, ErrorCode::Cancelled);
+
+    let mut status_ipc = IpcClient::connect(&sock).await.unwrap();
+    let status: StatusResult = status_ipc
+        .call::<(), _>(
+            "status-after-start-cancel",
+            Method::SystemStatus,
+            None,
+            Duration::from_secs(2),
+        )
+        .await
+        .unwrap()
+        .unwrap();
+    assert!(status.sessions.is_empty());
+    assert_eq!(status.browsers[0].session_count, 0);
+
+    let _ = release_tx.send(());
+    responder.await.unwrap();
+    handle.shutdown().await;
+}
+
+#[tokio::test]
+async fn timing_out_session_start_rolls_back_a_late_extension_success() {
+    let (handle, _sock) = spawn_daemon().await;
+    let state = handle.state();
+    let mut ws = connect_ext(handle.ws_addr()).await;
+    let _ = handshake_as_ext(&mut ws).await;
+    let (release_tx, release_rx) = tokio::sync::oneshot::channel();
+
+    let responder = tokio::spawn(async move {
+        respond_to_aborted_start(&mut ws, None, 4343).await;
+        let _ = release_rx.await;
+    });
+
+    let start = bsk::daemon::sessions::start_session(
+        &state.browsers,
+        &state.sessions,
+        &state.tool_queues,
+        None,
+        bsk::daemon::sessions::AgentWindowOptions::default(),
+        Duration::ZERO,
+        Duration::from_millis(20),
+        None,
+    )
+    .await;
+    assert!(matches!(
+        start,
+        Err(bsk::daemon::sessions::StartSessionError::Timeout)
+    ));
+    assert!(state.sessions.is_empty());
+
+    let _ = release_tx.send(());
+    responder.await.unwrap();
+    handle.shutdown().await;
+}
+
+#[tokio::test]
+async fn cancelling_session_stop_keeps_the_session_retryable() {
+    const STOP_RPC_ID: &str = "session-stop-cancel";
+
+    let (handle, sock) = spawn_daemon().await;
+    let mut ws = connect_ext(handle.ws_addr()).await;
+    let _ = handshake_as_ext(&mut ws).await;
+    let (stop_seen_tx, stop_seen_rx) = tokio::sync::oneshot::channel();
+    let (release_tx, release_rx) = tokio::sync::oneshot::channel();
+
+    let responder = tokio::spawn(async move {
+        respond_to_aborted_stop(&mut ws, Some(stop_seen_tx)).await;
+        let _ = release_rx.await;
+    });
+
+    let mut start_ipc = IpcClient::connect(&sock).await.unwrap();
+    let start: serde_json::Value = start_ipc
+        .call(
+            "start-before-stop-cancel",
+            Method::SessionStart,
+            Some(serde_json::json!({ "focused": false })),
+            Duration::from_secs(5),
+        )
+        .await
+        .unwrap()
+        .unwrap();
+    let session_id = start["session_id"].as_str().unwrap().to_string();
+
+    let mut stop_ipc = IpcClient::connect(&sock).await.unwrap();
+    let stop_session_id = session_id.clone();
+    let stop_call = tokio::spawn(async move {
+        let outcome: Result<serde_json::Value, RpcError> = stop_ipc
+            .call_with_id(
+                STOP_RPC_ID.to_string(),
+                Method::SessionStop,
+                Some(serde_json::json!({
+                    "session_id": stop_session_id,
+                    "all": false,
+                })),
+                Duration::from_secs(5),
+            )
+            .await
+            .unwrap();
+        outcome
+    });
+
+    stop_seen_rx.await.unwrap();
+    let mut cancel_ipc = IpcClient::connect(&sock).await.unwrap();
+    let cancel: CancelResult = cancel_ipc
+        .call(
+            "cancel-stop",
+            Method::Cancel,
+            Some(CancelParams {
+                rpc_id: STOP_RPC_ID.to_string(),
+            }),
+            Duration::from_secs(2),
+        )
+        .await
+        .unwrap()
+        .unwrap();
+    assert!(cancel.cancelled);
+
+    let stop_error = stop_call.await.unwrap().unwrap_err();
+    assert_eq!(stop_error.code, ErrorCode::Cancelled);
+
+    let mut status_ipc = IpcClient::connect(&sock).await.unwrap();
+    let status: StatusResult = status_ipc
+        .call::<(), _>(
+            "status-after-stop-cancel",
+            Method::SystemStatus,
+            None,
+            Duration::from_secs(2),
+        )
+        .await
+        .unwrap()
+        .unwrap();
+    assert_eq!(status.sessions.len(), 1);
+    assert_eq!(status.sessions[0].session_id, session_id);
+
+    let _ = release_tx.send(());
+    responder.await.unwrap();
+    handle.shutdown().await;
+}
+
+#[tokio::test]
+async fn timing_out_session_stop_cancels_extension_teardown_and_keeps_session() {
+    let (handle, sock) = spawn_daemon().await;
+    let state = handle.state();
+    let mut ws = connect_ext(handle.ws_addr()).await;
+    let _ = handshake_as_ext(&mut ws).await;
+    let (release_tx, release_rx) = tokio::sync::oneshot::channel();
+
+    let responder = tokio::spawn(async move {
+        respond_to_aborted_stop(&mut ws, None).await;
+        let _ = release_rx.await;
+    });
+
+    let mut start_ipc = IpcClient::connect(&sock).await.unwrap();
+    let start: serde_json::Value = start_ipc
+        .call(
+            "start-before-stop-timeout",
+            Method::SessionStart,
+            Some(serde_json::json!({ "focused": false })),
+            Duration::from_secs(5),
+        )
+        .await
+        .unwrap()
+        .unwrap();
+    let session_id =
+        bsk::daemon::sessions::SessionId(start["session_id"].as_str().unwrap().to_string());
+
+    let stop = bsk::daemon::sessions::stop_session(
+        &state.browsers,
+        &state.sessions,
+        &state.tool_queues,
+        &state.session_interrupts,
+        &session_id,
+        Duration::from_millis(20),
+        None,
+    )
+    .await;
+    assert!(matches!(
+        stop,
+        Err(bsk::daemon::sessions::StopSessionError::Timeout)
+    ));
+    assert!(state.sessions.get(&session_id).is_some());
+
+    let _ = release_tx.send(());
+    responder.await.unwrap();
+    handle.shutdown().await;
+}
+
 #[tokio::test]
 async fn session_idle_timeout_stops_and_unregisters_session() {
     let (handle, _sock) = spawn_daemon_with_session_idle(Duration::from_millis(50)).await;

crates/bsk-protocol/schema/tool_record_await_result.json

@@ -7,10 +7,18 @@
   ],
   "properties": {
     "trace": {
-      "$ref": "#/definitions/Trace"
+      "$ref": "#/definitions/RecordedTrace"
     }
   },
   "definitions": {
+    "FillCommit": {
+      "type": "string",
+      "enum": [
+        "enter",
+        "suggestion",
+        "blur"
+      ]
+    },
     "KeyModifier": {
       "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
       "type": "string",
@@ -21,7 +29,19 @@
         "shift"
       ]
     },
-    "PageRef": {
+    "NavigationCause": {
+      "type": "string",
+      "enum": [
+        "user_typed",
+        "link",
+        "form_submit",
+        "reload",
+        "history",
+        "script",
+        "browser"
+      ]
+    },
+    "PageRefV2": {
       "description": "Page context dictionary entry — referenced by steps via `page` id.",
       "type": "object",
       "required": [
@@ -43,7 +63,42 @@
         }
       }
     },
-    "SelectedOption": {
+    "RecordedTrace": {
+      "if": {
+        "required": [
+          "version"
+        ],
+        "properties": {
+          "version": {
+            "type": "integer"
+          }
+        }
+      },
+      "then": {
+        "$ref": "#/definitions/TraceV3"
+      },
+      "else": {
+        "$ref": "#/definitions/TraceV2"
+      }
+    },
+    "RecorderInfo": {
+      "type": "object",
+      "required": [
+        "bsk",
+        "vom"
+      ],
+      "properties": {
+        "bsk": {
+          "type": "string"
+        },
+        "vom": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        }
+      }
+    },
+    "SelectedOptionV2": {
       "description": "One selected option (`select` op).",
       "type": "object",
       "required": [
@@ -61,11 +116,53 @@
         }
       }
     },
-    "Step": {
-      "description": "One recorded user action — discriminated union by `op`.",
+    "SelectedOptionV3": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepEffectV2": {
+      "description": "Observed navigation after a step (objective fact only).",
+      "type": "object",
+      "required": [
+        "navigated_to"
+      ],
+      "properties": {
+        "navigated_to": {
+          "description": "Reference into `pages[]` for the destination page.",
+          "type": "string"
+        }
+      }
+    },
+    "StepResultV3": {
+      "type": "object",
+      "required": [
+        "state"
+      ],
+      "properties": {
+        "state": {
+          "type": "string"
+        }
+      }
+    },
+    "StepV2": {
+      "description": "One recorded user action — discriminated union by `op` (v2).",
       "oneOf": [
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -77,7 +174,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -105,7 +202,7 @@
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -117,7 +214,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -140,12 +237,12 @@
               "type": "string"
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -157,7 +254,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -180,12 +277,12 @@
               "type": "string"
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -198,7 +295,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -227,7 +324,7 @@
               ]
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             },
             "value": {
               "type": "string"
@@ -235,7 +332,7 @@
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -248,7 +345,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -273,16 +370,16 @@
             "selection": {
               "type": "array",
               "items": {
-                "$ref": "#/definitions/SelectedOption"
+                "$ref": "#/definitions/SelectedOptionV2"
               }
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -294,7 +391,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -331,7 +428,7 @@
             "target": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/TargetDescriptor"
+                  "$ref": "#/definitions/TargetDescriptorV2"
                 },
                 {
                   "type": "null"
@@ -342,21 +439,294 @@
         }
       ]
     },
-    "StepEffect": {
-      "description": "Observed navigation after a step (objective fact only).",
-      "type": "object",
-      "required": [
-        "navigated_to"
-      ],
-      "properties": {
-        "navigated_to": {
-          "description": "Reference into `pages[]` for the destination page.",
-          "type": "string"
+    "StepV3": {
+      "description": "One recorded user action — discriminated union by `op`.",
+      "oneOf": [
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "cause",
+            "id",
+            "op",
+            "result",
+            "state",
+            "to"
+          ],
+          "properties": {
+            "cause": {
+              "$ref": "#/definitions/NavigationCause"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "navigate"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "to": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "click"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "hover"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "commit",
+            "id",
+            "op",
+            "result",
+            "state",
+            "target",
+            "value"
+          ],
+          "properties": {
+            "commit": {
+              "$ref": "#/definitions/FillCommit"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "fill"
+              ]
+            },
+            "redacted": {
+              "type": "boolean"
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            },
+            "value": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "select"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "selection": {
+              "type": "array",
+              "items": {
+                "$ref": "#/definitions/SelectedOptionV3"
+              }
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "key",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "key": {
+              "type": "string"
+            },
+            "modifiers": {
+              "type": [
+                "array",
+                "null"
+              ],
+              "items": {
+                "$ref": "#/definitions/KeyModifier"
+              }
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "press"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/TargetDescriptorV3"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "scroll"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
         }
-      }
+      ]
     },
-    "TargetDescriptor": {
-      "description": "Stable semantic handle for an interacted element.\n\n`name` and `nearby_label` are **untrusted page text**.",
+    "StopReason": {
+      "type": "string",
+      "enum": [
+        "user_finish",
+        "cli_stop"
+      ]
+    },
+    "TargetDescriptorV2": {
+      "description": "Stable semantic handle for an interacted element (v2).\n\n`name` and `nearby_label` are **untrusted page text**.",
       "type": "object",
       "required": [
         "tag"
@@ -397,8 +767,83 @@
         }
       }
     },
-    "Trace": {
-      "description": "Persisted user-action trace exported by `tool.record_stop` / `await`.",
+    "TargetDescriptorV3": {
+      "description": "Stable semantic handle for an interacted element within a page observation.",
+      "type": "object",
+      "properties": {
+        "ctx": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "ref": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "unmatched": {
+          "type": "boolean"
+        }
+      }
+    },
+    "TraceEntry": {
+      "type": "object",
+      "required": [
+        "start_url"
+      ],
+      "properties": {
+        "start_url": {
+          "type": "string"
+        }
+      }
+    },
+    "TraceStateV3": {
+      "description": "Page observation dictionary entry — referenced by steps via `state` / `result.state`.",
+      "type": "object",
+      "required": [
+        "body",
+        "id",
+        "url"
+      ],
+      "properties": {
+        "body": {
+          "description": "Full page observation (front matter + VOM body + annotations).",
+          "type": "string"
+        },
+        "id": {
+          "type": "string"
+        },
+        "title": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "truncated": {
+          "type": "boolean"
+        },
+        "url": {
+          "type": "string"
+        }
+      }
+    },
+    "TraceV2": {
+      "title": "TraceV2",
+      "description": "Persisted user-action trace exported by legacy `tool.record_stop` / `await`.\n\nUnknown extension fields are ignored so older traces remain readable. `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace` classification.",
       "type": "object",
       "required": [
         "entry",
@@ -413,11 +858,10 @@
         "pages": {
           "type": "array",
           "items": {
-            "$ref": "#/definitions/PageRef"
+            "$ref": "#/definitions/PageRefV2"
           }
         },
         "purpose": {
-          "description": "Optional user-provided goal from `--purpose` (metadata only).",
           "type": [
             "string",
             "null"
@@ -433,25 +877,76 @@
             "null"
           ]
         },
+        "states": false,
         "steps": {
           "type": "array",
           "items": {
-            "$ref": "#/definitions/Step"
+            "$ref": "#/definitions/StepV2"
+          }
+        },
+        "version": {
+          "description": "Numeric version selects Trace v3. Legacy v2 envelopes omit this field.",
+          "not": {
+            "type": "integer"
           }
         }
       }
     },
-    "TraceEntry": {
-      "description": "Recording entry point — first URL the flow starts from.",
+    "TraceV3": {
+      "description": "Wire trace returned by `tool.record_stop` / `await`.",
       "type": "object",
       "required": [
-        "start_url"
+        "entry",
+        "recorded_at",
+        "recorder",
+        "states",
+        "steps",
+        "stopped_by",
+        "version"
       ],
       "properties": {
-        "start_url": {
+        "entry": {
+          "$ref": "#/definitions/TraceEntry"
+        },
+        "purpose": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "recorded_at": {
           "type": "string"
+        },
+        "recorder": {
+          "$ref": "#/definitions/RecorderInfo"
+        },
+        "started_at": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "states": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/TraceStateV3"
+          }
+        },
+        "steps": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/StepV3"
+          }
+        },
+        "stopped_by": {
+          "$ref": "#/definitions/StopReason"
+        },
+        "version": {
+          "type": "integer",
+          "const": 3
         }
-      }
+      },
+      "additionalProperties": false
     }
   }
 }

crates/bsk-protocol/schema/tool_record_stop_result.json

@@ -7,10 +7,18 @@
   ],
   "properties": {
     "trace": {
-      "$ref": "#/definitions/Trace"
+      "$ref": "#/definitions/RecordedTrace"
     }
   },
   "definitions": {
+    "FillCommit": {
+      "type": "string",
+      "enum": [
+        "enter",
+        "suggestion",
+        "blur"
+      ]
+    },
     "KeyModifier": {
       "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
       "type": "string",
@@ -21,7 +29,19 @@
         "shift"
       ]
     },
-    "PageRef": {
+    "NavigationCause": {
+      "type": "string",
+      "enum": [
+        "user_typed",
+        "link",
+        "form_submit",
+        "reload",
+        "history",
+        "script",
+        "browser"
+      ]
+    },
+    "PageRefV2": {
       "description": "Page context dictionary entry — referenced by steps via `page` id.",
       "type": "object",
       "required": [
@@ -43,7 +63,42 @@
         }
       }
     },
-    "SelectedOption": {
+    "RecordedTrace": {
+      "if": {
+        "required": [
+          "version"
+        ],
+        "properties": {
+          "version": {
+            "type": "integer"
+          }
+        }
+      },
+      "then": {
+        "$ref": "#/definitions/TraceV3"
+      },
+      "else": {
+        "$ref": "#/definitions/TraceV2"
+      }
+    },
+    "RecorderInfo": {
+      "type": "object",
+      "required": [
+        "bsk",
+        "vom"
+      ],
+      "properties": {
+        "bsk": {
+          "type": "string"
+        },
+        "vom": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        }
+      }
+    },
+    "SelectedOptionV2": {
       "description": "One selected option (`select` op).",
       "type": "object",
       "required": [
@@ -61,11 +116,53 @@
         }
       }
     },
-    "Step": {
-      "description": "One recorded user action — discriminated union by `op`.",
+    "SelectedOptionV3": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepEffectV2": {
+      "description": "Observed navigation after a step (objective fact only).",
+      "type": "object",
+      "required": [
+        "navigated_to"
+      ],
+      "properties": {
+        "navigated_to": {
+          "description": "Reference into `pages[]` for the destination page.",
+          "type": "string"
+        }
+      }
+    },
+    "StepResultV3": {
+      "type": "object",
+      "required": [
+        "state"
+      ],
+      "properties": {
+        "state": {
+          "type": "string"
+        }
+      }
+    },
+    "StepV2": {
+      "description": "One recorded user action — discriminated union by `op` (v2).",
       "oneOf": [
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -77,7 +174,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -105,7 +202,7 @@
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -117,7 +214,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -140,12 +237,12 @@
               "type": "string"
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -157,7 +254,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -180,12 +277,12 @@
               "type": "string"
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -198,7 +295,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -227,7 +324,7 @@
               ]
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             },
             "value": {
               "type": "string"
@@ -235,7 +332,7 @@
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -248,7 +345,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -273,16 +370,16 @@
             "selection": {
               "type": "array",
               "items": {
-                "$ref": "#/definitions/SelectedOption"
+                "$ref": "#/definitions/SelectedOptionV2"
               }
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -294,7 +391,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -331,7 +428,7 @@
             "target": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/TargetDescriptor"
+                  "$ref": "#/definitions/TargetDescriptorV2"
                 },
                 {
                   "type": "null"
@@ -342,21 +439,294 @@
         }
       ]
     },
-    "StepEffect": {
-      "description": "Observed navigation after a step (objective fact only).",
-      "type": "object",
-      "required": [
-        "navigated_to"
-      ],
-      "properties": {
-        "navigated_to": {
-          "description": "Reference into `pages[]` for the destination page.",
-          "type": "string"
+    "StepV3": {
+      "description": "One recorded user action — discriminated union by `op`.",
+      "oneOf": [
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "cause",
+            "id",
+            "op",
+            "result",
+            "state",
+            "to"
+          ],
+          "properties": {
+            "cause": {
+              "$ref": "#/definitions/NavigationCause"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "navigate"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "to": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "click"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "hover"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "commit",
+            "id",
+            "op",
+            "result",
+            "state",
+            "target",
+            "value"
+          ],
+          "properties": {
+            "commit": {
+              "$ref": "#/definitions/FillCommit"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "fill"
+              ]
+            },
+            "redacted": {
+              "type": "boolean"
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            },
+            "value": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "select"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "selection": {
+              "type": "array",
+              "items": {
+                "$ref": "#/definitions/SelectedOptionV3"
+              }
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "key",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "key": {
+              "type": "string"
+            },
+            "modifiers": {
+              "type": [
+                "array",
+                "null"
+              ],
+              "items": {
+                "$ref": "#/definitions/KeyModifier"
+              }
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "press"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/TargetDescriptorV3"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "scroll"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
         }
-      }
+      ]
     },
-    "TargetDescriptor": {
-      "description": "Stable semantic handle for an interacted element.\n\n`name` and `nearby_label` are **untrusted page text**.",
+    "StopReason": {
+      "type": "string",
+      "enum": [
+        "user_finish",
+        "cli_stop"
+      ]
+    },
+    "TargetDescriptorV2": {
+      "description": "Stable semantic handle for an interacted element (v2).\n\n`name` and `nearby_label` are **untrusted page text**.",
       "type": "object",
       "required": [
         "tag"
@@ -397,8 +767,83 @@
         }
       }
     },
-    "Trace": {
-      "description": "Persisted user-action trace exported by `tool.record_stop` / `await`.",
+    "TargetDescriptorV3": {
+      "description": "Stable semantic handle for an interacted element within a page observation.",
+      "type": "object",
+      "properties": {
+        "ctx": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "ref": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "unmatched": {
+          "type": "boolean"
+        }
+      }
+    },
+    "TraceEntry": {
+      "type": "object",
+      "required": [
+        "start_url"
+      ],
+      "properties": {
+        "start_url": {
+          "type": "string"
+        }
+      }
+    },
+    "TraceStateV3": {
+      "description": "Page observation dictionary entry — referenced by steps via `state` / `result.state`.",
+      "type": "object",
+      "required": [
+        "body",
+        "id",
+        "url"
+      ],
+      "properties": {
+        "body": {
+          "description": "Full page observation (front matter + VOM body + annotations).",
+          "type": "string"
+        },
+        "id": {
+          "type": "string"
+        },
+        "title": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "truncated": {
+          "type": "boolean"
+        },
+        "url": {
+          "type": "string"
+        }
+      }
+    },
+    "TraceV2": {
+      "title": "TraceV2",
+      "description": "Persisted user-action trace exported by legacy `tool.record_stop` / `await`.\n\nUnknown extension fields are ignored so older traces remain readable. `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace` classification.",
       "type": "object",
       "required": [
         "entry",
@@ -413,11 +858,10 @@
         "pages": {
           "type": "array",
           "items": {
-            "$ref": "#/definitions/PageRef"
+            "$ref": "#/definitions/PageRefV2"
           }
         },
         "purpose": {
-          "description": "Optional user-provided goal from `--purpose` (metadata only).",
           "type": [
             "string",
             "null"
@@ -433,25 +877,76 @@
             "null"
           ]
         },
+        "states": false,
         "steps": {
           "type": "array",
           "items": {
-            "$ref": "#/definitions/Step"
+            "$ref": "#/definitions/StepV2"
+          }
+        },
+        "version": {
+          "description": "Numeric version selects Trace v3. Legacy v2 envelopes omit this field.",
+          "not": {
+            "type": "integer"
           }
         }
       }
     },
-    "TraceEntry": {
-      "description": "Recording entry point — first URL the flow starts from.",
+    "TraceV3": {
+      "description": "Wire trace returned by `tool.record_stop` / `await`.",
       "type": "object",
       "required": [
-        "start_url"
+        "entry",
+        "recorded_at",
+        "recorder",
+        "states",
+        "steps",
+        "stopped_by",
+        "version"
       ],
       "properties": {
-        "start_url": {
+        "entry": {
+          "$ref": "#/definitions/TraceEntry"
+        },
+        "purpose": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "recorded_at": {
           "type": "string"
+        },
+        "recorder": {
+          "$ref": "#/definitions/RecorderInfo"
+        },
+        "started_at": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "states": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/TraceStateV3"
+          }
+        },
+        "steps": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/StepV3"
+          }
+        },
+        "stopped_by": {
+          "$ref": "#/definitions/StopReason"
+        },
+        "version": {
+          "type": "integer",
+          "const": 3
         }
-      }
+      },
+      "additionalProperties": false
     }
   }
 }

crates/bsk-protocol/schema/trace.json

@@ -1,49 +1,31 @@
 {
   "$schema": "http://json-schema.org/draft-07/schema#",
-  "title": "Trace",
-  "description": "Persisted user-action trace exported by `tool.record_stop` / `await`.",
-  "type": "object",
-  "required": [
-    "entry",
-    "pages",
-    "recorded_at",
-    "steps"
-  ],
-  "properties": {
-    "entry": {
-      "$ref": "#/definitions/TraceEntry"
-    },
-    "pages": {
-      "type": "array",
-      "items": {
-        "$ref": "#/definitions/PageRef"
-      }
-    },
-    "purpose": {
-      "description": "Optional user-provided goal from `--purpose` (metadata only).",
-      "type": [
-        "string",
-        "null"
-      ]
-    },
-    "recorded_at": {
-      "description": "RFC 3339 timestamp when recording stopped.",
-      "type": "string"
-    },
-    "started_at": {
-      "type": [
-        "string",
-        "null"
-      ]
-    },
-    "steps": {
-      "type": "array",
-      "items": {
-        "$ref": "#/definitions/Step"
+  "title": "RecordedTrace",
+  "if": {
+    "required": [
+      "version"
+    ],
+    "properties": {
+      "version": {
+        "type": "integer"
       }
     }
   },
+  "then": {
+    "$ref": "#/definitions/TraceV3"
+  },
+  "else": {
+    "$ref": "#/definitions/TraceV2"
+  },
   "definitions": {
+    "FillCommit": {
+      "type": "string",
+      "enum": [
+        "enter",
+        "suggestion",
+        "blur"
+      ]
+    },
     "KeyModifier": {
       "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
       "type": "string",
@@ -54,7 +36,19 @@
         "shift"
       ]
     },
-    "PageRef": {
+    "NavigationCause": {
+      "type": "string",
+      "enum": [
+        "user_typed",
+        "link",
+        "form_submit",
+        "reload",
+        "history",
+        "script",
+        "browser"
+      ]
+    },
+    "PageRefV2": {
       "description": "Page context dictionary entry — referenced by steps via `page` id.",
       "type": "object",
       "required": [
@@ -76,7 +70,24 @@
         }
       }
     },
-    "SelectedOption": {
+    "RecorderInfo": {
+      "type": "object",
+      "required": [
+        "bsk",
+        "vom"
+      ],
+      "properties": {
+        "bsk": {
+          "type": "string"
+        },
+        "vom": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        }
+      }
+    },
+    "SelectedOptionV2": {
       "description": "One selected option (`select` op).",
       "type": "object",
       "required": [
@@ -94,11 +105,53 @@
         }
       }
     },
-    "Step": {
-      "description": "One recorded user action — discriminated union by `op`.",
+    "SelectedOptionV3": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepEffectV2": {
+      "description": "Observed navigation after a step (objective fact only).",
+      "type": "object",
+      "required": [
+        "navigated_to"
+      ],
+      "properties": {
+        "navigated_to": {
+          "description": "Reference into `pages[]` for the destination page.",
+          "type": "string"
+        }
+      }
+    },
+    "StepResultV3": {
+      "type": "object",
+      "required": [
+        "state"
+      ],
+      "properties": {
+        "state": {
+          "type": "string"
+        }
+      }
+    },
+    "StepV2": {
+      "description": "One recorded user action — discriminated union by `op` (v2).",
       "oneOf": [
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -110,7 +163,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -138,7 +191,7 @@
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -150,7 +203,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -173,12 +226,12 @@
               "type": "string"
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -190,7 +243,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -213,12 +266,12 @@
               "type": "string"
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -231,7 +284,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -260,7 +313,7 @@
               ]
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             },
             "value": {
               "type": "string"
@@ -268,7 +321,7 @@
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -281,7 +334,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -306,16 +359,16 @@
             "selection": {
               "type": "array",
               "items": {
-                "$ref": "#/definitions/SelectedOption"
+                "$ref": "#/definitions/SelectedOptionV2"
               }
             },
             "target": {
-              "$ref": "#/definitions/TargetDescriptor"
+              "$ref": "#/definitions/TargetDescriptorV2"
             }
           }
         },
         {
-          "description": "Fields shared by every step variant (flattened in JSON).",
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
           "type": "object",
           "required": [
             "id",
@@ -327,7 +380,7 @@
             "effect": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/StepEffect"
+                  "$ref": "#/definitions/StepEffectV2"
                 },
                 {
                   "type": "null"
@@ -364,7 +417,7 @@
             "target": {
               "anyOf": [
                 {
-                  "$ref": "#/definitions/TargetDescriptor"
+                  "$ref": "#/definitions/TargetDescriptorV2"
                 },
                 {
                   "type": "null"
@@ -375,21 +428,294 @@
         }
       ]
     },
-    "StepEffect": {
-      "description": "Observed navigation after a step (objective fact only).",
-      "type": "object",
-      "required": [
-        "navigated_to"
-      ],
-      "properties": {
-        "navigated_to": {
-          "description": "Reference into `pages[]` for the destination page.",
-          "type": "string"
+    "StepV3": {
+      "description": "One recorded user action — discriminated union by `op`.",
+      "oneOf": [
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "cause",
+            "id",
+            "op",
+            "result",
+            "state",
+            "to"
+          ],
+          "properties": {
+            "cause": {
+              "$ref": "#/definitions/NavigationCause"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "navigate"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "to": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "click"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "hover"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "commit",
+            "id",
+            "op",
+            "result",
+            "state",
+            "target",
+            "value"
+          ],
+          "properties": {
+            "commit": {
+              "$ref": "#/definitions/FillCommit"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "fill"
+              ]
+            },
+            "redacted": {
+              "type": "boolean"
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            },
+            "value": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "select"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "selection": {
+              "type": "array",
+              "items": {
+                "$ref": "#/definitions/SelectedOptionV3"
+              }
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "key",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "key": {
+              "type": "string"
+            },
+            "modifiers": {
+              "type": [
+                "array",
+                "null"
+              ],
+              "items": {
+                "$ref": "#/definitions/KeyModifier"
+              }
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "press"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/TargetDescriptorV3"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "scroll"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
         }
-      }
+      ]
     },
-    "TargetDescriptor": {
-      "description": "Stable semantic handle for an interacted element.\n\n`name` and `nearby_label` are **untrusted page text**.",
+    "StopReason": {
+      "type": "string",
+      "enum": [
+        "user_finish",
+        "cli_stop"
+      ]
+    },
+    "TargetDescriptorV2": {
+      "description": "Stable semantic handle for an interacted element (v2).\n\n`name` and `nearby_label` are **untrusted page text**.",
       "type": "object",
       "required": [
         "tag"
@@ -430,8 +756,40 @@
         }
       }
     },
+    "TargetDescriptorV3": {
+      "description": "Stable semantic handle for an interacted element within a page observation.",
+      "type": "object",
+      "properties": {
+        "ctx": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "ref": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "unmatched": {
+          "type": "boolean"
+        }
+      }
+    },
     "TraceEntry": {
-      "description": "Recording entry point — first URL the flow starts from.",
       "type": "object",
       "required": [
         "start_url"
@@ -441,6 +799,143 @@
           "type": "string"
         }
       }
+    },
+    "TraceStateV3": {
+      "description": "Page observation dictionary entry — referenced by steps via `state` / `result.state`.",
+      "type": "object",
+      "required": [
+        "body",
+        "id",
+        "url"
+      ],
+      "properties": {
+        "body": {
+          "description": "Full page observation (front matter + VOM body + annotations).",
+          "type": "string"
+        },
+        "id": {
+          "type": "string"
+        },
+        "title": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "truncated": {
+          "type": "boolean"
+        },
+        "url": {
+          "type": "string"
+        }
+      }
+    },
+    "TraceV2": {
+      "title": "TraceV2",
+      "description": "Persisted user-action trace exported by legacy `tool.record_stop` / `await`.\n\nUnknown extension fields are ignored so older traces remain readable. `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace` classification.",
+      "type": "object",
+      "required": [
+        "entry",
+        "pages",
+        "recorded_at",
+        "steps"
+      ],
+      "properties": {
+        "entry": {
+          "$ref": "#/definitions/TraceEntry"
+        },
+        "pages": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/PageRefV2"
+          }
+        },
+        "purpose": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "recorded_at": {
+          "description": "RFC 3339 timestamp when recording stopped.",
+          "type": "string"
+        },
+        "started_at": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "states": false,
+        "steps": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/StepV2"
+          }
+        },
+        "version": {
+          "description": "Numeric version selects Trace v3. Legacy v2 envelopes omit this field.",
+          "not": {
+            "type": "integer"
+          }
+        }
+      }
+    },
+    "TraceV3": {
+      "description": "Wire trace returned by `tool.record_stop` / `await`.",
+      "type": "object",
+      "required": [
+        "entry",
+        "recorded_at",
+        "recorder",
+        "states",
+        "steps",
+        "stopped_by",
+        "version"
+      ],
+      "properties": {
+        "entry": {
+          "$ref": "#/definitions/TraceEntry"
+        },
+        "purpose": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "recorded_at": {
+          "type": "string"
+        },
+        "recorder": {
+          "$ref": "#/definitions/RecorderInfo"
+        },
+        "started_at": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "states": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/TraceStateV3"
+          }
+        },
+        "steps": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/StepV3"
+          }
+        },
+        "stopped_by": {
+          "$ref": "#/definitions/StopReason"
+        },
+        "version": {
+          "type": "integer",
+          "const": 3
+        }
+      },
+      "additionalProperties": false
     }
   }
 }

crates/bsk-protocol/schema/trace_step.json

@@ -1,286 +1,32 @@
 {
   "$schema": "http://json-schema.org/draft-07/schema#",
-  "title": "Step",
-  "description": "One recorded user action — discriminated union by `op`.",
-  "oneOf": [
-    {
-      "description": "Fields shared by every step variant (flattened in JSON).",
-      "type": "object",
-      "required": [
-        "id",
-        "op",
-        "page",
-        "to"
-      ],
-      "properties": {
-        "effect": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/StepEffect"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        },
-        "id": {
-          "type": "integer",
-          "format": "uint32",
-          "minimum": 0.0
-        },
-        "op": {
-          "type": "string",
-          "enum": [
-            "navigate"
-          ]
-        },
-        "page": {
-          "description": "Reference into `pages[]`.",
-          "type": "string"
-        },
-        "to": {
-          "type": "string"
-        }
-      }
-    },
-    {
-      "description": "Fields shared by every step variant (flattened in JSON).",
-      "type": "object",
-      "required": [
-        "id",
-        "op",
-        "page",
-        "target"
-      ],
-      "properties": {
-        "effect": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/StepEffect"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        },
-        "id": {
-          "type": "integer",
-          "format": "uint32",
-          "minimum": 0.0
-        },
-        "op": {
-          "type": "string",
-          "enum": [
-            "click"
-          ]
-        },
-        "page": {
-          "description": "Reference into `pages[]`.",
-          "type": "string"
-        },
-        "target": {
-          "$ref": "#/definitions/TargetDescriptor"
-        }
-      }
-    },
-    {
-      "description": "Fields shared by every step variant (flattened in JSON).",
-      "type": "object",
-      "required": [
-        "id",
-        "op",
-        "page",
-        "target"
-      ],
-      "properties": {
-        "effect": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/StepEffect"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        },
-        "id": {
-          "type": "integer",
-          "format": "uint32",
-          "minimum": 0.0
-        },
-        "op": {
-          "type": "string",
-          "enum": [
-            "hover"
-          ]
-        },
-        "page": {
-          "description": "Reference into `pages[]`.",
-          "type": "string"
-        },
-        "target": {
-          "$ref": "#/definitions/TargetDescriptor"
-        }
-      }
-    },
-    {
-      "description": "Fields shared by every step variant (flattened in JSON).",
-      "type": "object",
-      "required": [
-        "id",
-        "op",
-        "page",
-        "target",
-        "value"
-      ],
-      "properties": {
-        "effect": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/StepEffect"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        },
-        "id": {
-          "type": "integer",
-          "format": "uint32",
-          "minimum": 0.0
-        },
-        "op": {
-          "type": "string",
-          "enum": [
-            "fill"
-          ]
-        },
-        "page": {
-          "description": "Reference into `pages[]`.",
-          "type": "string"
-        },
-        "redacted": {
-          "type": [
-            "boolean",
-            "null"
-          ]
-        },
-        "target": {
-          "$ref": "#/definitions/TargetDescriptor"
-        },
-        "value": {
-          "type": "string"
-        }
-      }
-    },
-    {
-      "description": "Fields shared by every step variant (flattened in JSON).",
-      "type": "object",
-      "required": [
-        "id",
-        "op",
-        "page",
-        "selection",
-        "target"
-      ],
-      "properties": {
-        "effect": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/StepEffect"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        },
-        "id": {
-          "type": "integer",
-          "format": "uint32",
-          "minimum": 0.0
-        },
-        "op": {
-          "type": "string",
-          "enum": [
-            "select"
-          ]
-        },
-        "page": {
-          "description": "Reference into `pages[]`.",
-          "type": "string"
-        },
-        "selection": {
-          "type": "array",
-          "items": {
-            "$ref": "#/definitions/SelectedOption"
-          }
-        },
-        "target": {
-          "$ref": "#/definitions/TargetDescriptor"
-        }
-      }
-    },
-    {
-      "description": "Fields shared by every step variant (flattened in JSON).",
-      "type": "object",
-      "required": [
-        "id",
-        "key",
-        "op",
-        "page"
-      ],
-      "properties": {
-        "effect": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/StepEffect"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        },
-        "id": {
-          "type": "integer",
-          "format": "uint32",
-          "minimum": 0.0
-        },
-        "key": {
-          "type": "string"
-        },
-        "modifiers": {
-          "type": [
-            "array",
-            "null"
-          ],
-          "items": {
-            "$ref": "#/definitions/KeyModifier"
-          }
-        },
-        "op": {
-          "type": "string",
-          "enum": [
-            "press"
-          ]
-        },
-        "page": {
-          "description": "Reference into `pages[]`.",
-          "type": "string"
-        },
-        "target": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/TargetDescriptor"
-            },
-            {
-              "type": "null"
-            }
-          ]
-        }
-      }
-    }
-  ],
+  "title": "RecordedStep",
+  "not": {
+    "required": [
+      "page",
+      "state"
+    ]
+  },
+  "if": {
+    "required": [
+      "state"
+    ]
+  },
+  "then": {
+    "$ref": "#/definitions/StepV3"
+  },
+  "else": {
+    "$ref": "#/definitions/StepV2"
+  },
   "definitions": {
+    "FillCommit": {
+      "type": "string",
+      "enum": [
+        "enter",
+        "suggestion",
+        "blur"
+      ]
+    },
     "KeyModifier": {
       "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
       "type": "string",
@@ -291,7 +37,19 @@
         "shift"
       ]
     },
-    "SelectedOption": {
+    "NavigationCause": {
+      "type": "string",
+      "enum": [
+        "user_typed",
+        "link",
+        "form_submit",
+        "reload",
+        "history",
+        "script",
+        "browser"
+      ]
+    },
+    "SelectedOptionV2": {
       "description": "One selected option (`select` op).",
       "type": "object",
       "required": [
@@ -309,7 +67,25 @@
         }
       }
     },
-    "StepEffect": {
+    "SelectedOptionV3": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepEffectV2": {
       "description": "Observed navigation after a step (objective fact only).",
       "type": "object",
       "required": [
@@ -322,8 +98,579 @@
         }
       }
     },
-    "TargetDescriptor": {
-      "description": "Stable semantic handle for an interacted element.\n\n`name` and `nearby_label` are **untrusted page text**.",
+    "StepResultV3": {
+      "type": "object",
+      "required": [
+        "state"
+      ],
+      "properties": {
+        "state": {
+          "type": "string"
+        }
+      }
+    },
+    "StepV2": {
+      "description": "One recorded user action — discriminated union by `op` (v2).",
+      "oneOf": [
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "to"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "navigate"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "to": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "target"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "click"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "target"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "hover"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "target",
+            "value"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "fill"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "redacted": {
+              "type": [
+                "boolean",
+                "null"
+              ]
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            },
+            "value": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "selection",
+            "target"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "select"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "selection": {
+              "type": "array",
+              "items": {
+                "$ref": "#/definitions/SelectedOptionV2"
+              }
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "key",
+            "op",
+            "page"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "key": {
+              "type": "string"
+            },
+            "modifiers": {
+              "type": [
+                "array",
+                "null"
+              ],
+              "items": {
+                "$ref": "#/definitions/KeyModifier"
+              }
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "press"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "target": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/TargetDescriptorV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            }
+          }
+        }
+      ]
+    },
+    "StepV3": {
+      "description": "One recorded user action — discriminated union by `op`.",
+      "oneOf": [
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "cause",
+            "id",
+            "op",
+            "result",
+            "state",
+            "to"
+          ],
+          "properties": {
+            "cause": {
+              "$ref": "#/definitions/NavigationCause"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "navigate"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "to": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "click"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "hover"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "commit",
+            "id",
+            "op",
+            "result",
+            "state",
+            "target",
+            "value"
+          ],
+          "properties": {
+            "commit": {
+              "$ref": "#/definitions/FillCommit"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "fill"
+              ]
+            },
+            "redacted": {
+              "type": "boolean"
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            },
+            "value": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "select"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "selection": {
+              "type": "array",
+              "items": {
+                "$ref": "#/definitions/SelectedOptionV3"
+              }
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "key",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "key": {
+              "type": "string"
+            },
+            "modifiers": {
+              "type": [
+                "array",
+                "null"
+              ],
+              "items": {
+                "$ref": "#/definitions/KeyModifier"
+              }
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "press"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/TargetDescriptorV3"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "scroll"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
+        }
+      ]
+    },
+    "TargetDescriptorV2": {
+      "description": "Stable semantic handle for an interacted element (v2).\n\n`name` and `nearby_label` are **untrusted page text**.",
       "type": "object",
       "required": [
         "tag"
@@ -363,6 +710,39 @@
           "type": "string"
         }
       }
+    },
+    "TargetDescriptorV3": {
+      "description": "Stable semantic handle for an interacted element within a page observation.",
+      "type": "object",
+      "properties": {
+        "ctx": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "ref": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "unmatched": {
+          "type": "boolean"
+        }
+      }
     }
   }
 }

crates/bsk-protocol/schema/trace_step_v2.json

@@ -0,0 +1,368 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "StepV2",
+  "description": "One recorded user action — discriminated union by `op` (v2).",
+  "oneOf": [
+    {
+      "description": "Fields shared by every v2 step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "page",
+        "to"
+      ],
+      "properties": {
+        "effect": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/StepEffectV2"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "navigate"
+          ]
+        },
+        "page": {
+          "description": "Reference into `pages[]`.",
+          "type": "string"
+        },
+        "to": {
+          "type": "string"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every v2 step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "page",
+        "target"
+      ],
+      "properties": {
+        "effect": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/StepEffectV2"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "click"
+          ]
+        },
+        "page": {
+          "description": "Reference into `pages[]`.",
+          "type": "string"
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV2"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every v2 step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "page",
+        "target"
+      ],
+      "properties": {
+        "effect": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/StepEffectV2"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "hover"
+          ]
+        },
+        "page": {
+          "description": "Reference into `pages[]`.",
+          "type": "string"
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV2"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every v2 step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "page",
+        "target",
+        "value"
+      ],
+      "properties": {
+        "effect": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/StepEffectV2"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "fill"
+          ]
+        },
+        "page": {
+          "description": "Reference into `pages[]`.",
+          "type": "string"
+        },
+        "redacted": {
+          "type": [
+            "boolean",
+            "null"
+          ]
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV2"
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every v2 step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "page",
+        "selection",
+        "target"
+      ],
+      "properties": {
+        "effect": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/StepEffectV2"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "select"
+          ]
+        },
+        "page": {
+          "description": "Reference into `pages[]`.",
+          "type": "string"
+        },
+        "selection": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/SelectedOptionV2"
+          }
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV2"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every v2 step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "key",
+        "op",
+        "page"
+      ],
+      "properties": {
+        "effect": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/StepEffectV2"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "key": {
+          "type": "string"
+        },
+        "modifiers": {
+          "type": [
+            "array",
+            "null"
+          ],
+          "items": {
+            "$ref": "#/definitions/KeyModifier"
+          }
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "press"
+          ]
+        },
+        "page": {
+          "description": "Reference into `pages[]`.",
+          "type": "string"
+        },
+        "target": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        }
+      }
+    }
+  ],
+  "definitions": {
+    "KeyModifier": {
+      "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
+      "type": "string",
+      "enum": [
+        "alt",
+        "ctrl",
+        "meta",
+        "shift"
+      ]
+    },
+    "SelectedOptionV2": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepEffectV2": {
+      "description": "Observed navigation after a step (objective fact only).",
+      "type": "object",
+      "required": [
+        "navigated_to"
+      ],
+      "properties": {
+        "navigated_to": {
+          "description": "Reference into `pages[]` for the destination page.",
+          "type": "string"
+        }
+      }
+    },
+    "TargetDescriptorV2": {
+      "description": "Stable semantic handle for an interacted element (v2).\n\n`name` and `nearby_label` are **untrusted page text**.",
+      "type": "object",
+      "required": [
+        "tag"
+      ],
+      "properties": {
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name_attr": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "nearby_label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "placeholder": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "tag": {
+          "type": "string"
+        }
+      }
+    }
+  }
+}

crates/bsk-protocol/schema/trace_step_v3.json

@@ -0,0 +1,375 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "StepV3",
+  "description": "One recorded user action — discriminated union by `op`.",
+  "oneOf": [
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "cause",
+        "id",
+        "op",
+        "result",
+        "state",
+        "to"
+      ],
+      "properties": {
+        "cause": {
+          "$ref": "#/definitions/NavigationCause"
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "navigate"
+          ]
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        },
+        "to": {
+          "type": "string"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "result",
+        "state",
+        "target"
+      ],
+      "properties": {
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "click"
+          ]
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV3"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "result",
+        "state",
+        "target"
+      ],
+      "properties": {
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "hover"
+          ]
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV3"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "commit",
+        "id",
+        "op",
+        "result",
+        "state",
+        "target",
+        "value"
+      ],
+      "properties": {
+        "commit": {
+          "$ref": "#/definitions/FillCommit"
+        },
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "fill"
+          ]
+        },
+        "redacted": {
+          "type": "boolean"
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV3"
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "result",
+        "state",
+        "target"
+      ],
+      "properties": {
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "select"
+          ]
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "selection": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/SelectedOptionV3"
+          }
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        },
+        "target": {
+          "$ref": "#/definitions/TargetDescriptorV3"
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "key",
+        "op",
+        "result",
+        "state"
+      ],
+      "properties": {
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "key": {
+          "type": "string"
+        },
+        "modifiers": {
+          "type": [
+            "array",
+            "null"
+          ],
+          "items": {
+            "$ref": "#/definitions/KeyModifier"
+          }
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "press"
+          ]
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        },
+        "target": {
+          "anyOf": [
+            {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            },
+            {
+              "type": "null"
+            }
+          ]
+        }
+      }
+    },
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "result",
+        "state"
+      ],
+      "properties": {
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "scroll"
+          ]
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        }
+      }
+    }
+  ],
+  "definitions": {
+    "FillCommit": {
+      "type": "string",
+      "enum": [
+        "enter",
+        "suggestion",
+        "blur"
+      ]
+    },
+    "KeyModifier": {
+      "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
+      "type": "string",
+      "enum": [
+        "alt",
+        "ctrl",
+        "meta",
+        "shift"
+      ]
+    },
+    "NavigationCause": {
+      "type": "string",
+      "enum": [
+        "user_typed",
+        "link",
+        "form_submit",
+        "reload",
+        "history",
+        "script",
+        "browser"
+      ]
+    },
+    "SelectedOptionV3": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepResultV3": {
+      "type": "object",
+      "required": [
+        "state"
+      ],
+      "properties": {
+        "state": {
+          "type": "string"
+        }
+      }
+    },
+    "TargetDescriptorV3": {
+      "description": "Stable semantic handle for an interacted element within a page observation.",
+      "type": "object",
+      "properties": {
+        "ctx": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "ref": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "unmatched": {
+          "type": "boolean"
+        }
+      }
+    }
+  }
+}

crates/bsk-protocol/schema/trace_v2.json

@@ -0,0 +1,451 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "TraceV2",
+  "description": "Persisted user-action trace exported by legacy `tool.record_stop` / `await`.\n\nUnknown extension fields are ignored so older traces remain readable. `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace` classification.",
+  "type": "object",
+  "required": [
+    "entry",
+    "pages",
+    "recorded_at",
+    "steps"
+  ],
+  "properties": {
+    "entry": {
+      "$ref": "#/definitions/TraceEntry"
+    },
+    "pages": {
+      "type": "array",
+      "items": {
+        "$ref": "#/definitions/PageRefV2"
+      }
+    },
+    "purpose": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "recorded_at": {
+      "description": "RFC 3339 timestamp when recording stopped.",
+      "type": "string"
+    },
+    "started_at": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "states": false,
+    "steps": {
+      "type": "array",
+      "items": {
+        "$ref": "#/definitions/StepV2"
+      }
+    },
+    "version": {
+      "description": "Numeric version selects Trace v3. Legacy v2 envelopes omit this field.",
+      "not": {
+        "type": "integer"
+      }
+    }
+  },
+  "definitions": {
+    "KeyModifier": {
+      "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
+      "type": "string",
+      "enum": [
+        "alt",
+        "ctrl",
+        "meta",
+        "shift"
+      ]
+    },
+    "PageRefV2": {
+      "description": "Page context dictionary entry — referenced by steps via `page` id.",
+      "type": "object",
+      "required": [
+        "id",
+        "url"
+      ],
+      "properties": {
+        "id": {
+          "type": "string"
+        },
+        "title": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "url": {
+          "type": "string"
+        }
+      }
+    },
+    "SelectedOptionV2": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepEffectV2": {
+      "description": "Observed navigation after a step (objective fact only).",
+      "type": "object",
+      "required": [
+        "navigated_to"
+      ],
+      "properties": {
+        "navigated_to": {
+          "description": "Reference into `pages[]` for the destination page.",
+          "type": "string"
+        }
+      }
+    },
+    "StepV2": {
+      "description": "One recorded user action — discriminated union by `op` (v2).",
+      "oneOf": [
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "to"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "navigate"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "to": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "target"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "click"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "target"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "hover"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "target",
+            "value"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "fill"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "redacted": {
+              "type": [
+                "boolean",
+                "null"
+              ]
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            },
+            "value": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "page",
+            "selection",
+            "target"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "select"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "selection": {
+              "type": "array",
+              "items": {
+                "$ref": "#/definitions/SelectedOptionV2"
+              }
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV2"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every v2 step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "key",
+            "op",
+            "page"
+          ],
+          "properties": {
+            "effect": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/StepEffectV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "key": {
+              "type": "string"
+            },
+            "modifiers": {
+              "type": [
+                "array",
+                "null"
+              ],
+              "items": {
+                "$ref": "#/definitions/KeyModifier"
+              }
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "press"
+              ]
+            },
+            "page": {
+              "description": "Reference into `pages[]`.",
+              "type": "string"
+            },
+            "target": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/TargetDescriptorV2"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            }
+          }
+        }
+      ]
+    },
+    "TargetDescriptorV2": {
+      "description": "Stable semantic handle for an interacted element (v2).\n\n`name` and `nearby_label` are **untrusted page text**.",
+      "type": "object",
+      "required": [
+        "tag"
+      ],
+      "properties": {
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name_attr": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "nearby_label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "placeholder": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "tag": {
+          "type": "string"
+        }
+      }
+    },
+    "TraceEntry": {
+      "type": "object",
+      "required": [
+        "start_url"
+      ],
+      "properties": {
+        "start_url": {
+          "type": "string"
+        }
+      }
+    }
+  }
+}

crates/bsk-protocol/schema/trace_v3.json

@@ -0,0 +1,496 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "TraceV3",
+  "description": "Wire trace returned by `tool.record_stop` / `await`.",
+  "type": "object",
+  "required": [
+    "entry",
+    "recorded_at",
+    "recorder",
+    "states",
+    "steps",
+    "stopped_by",
+    "version"
+  ],
+  "properties": {
+    "entry": {
+      "$ref": "#/definitions/TraceEntry"
+    },
+    "purpose": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "recorded_at": {
+      "type": "string"
+    },
+    "recorder": {
+      "$ref": "#/definitions/RecorderInfo"
+    },
+    "started_at": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "states": {
+      "type": "array",
+      "items": {
+        "$ref": "#/definitions/TraceStateV3"
+      }
+    },
+    "steps": {
+      "type": "array",
+      "items": {
+        "$ref": "#/definitions/StepV3"
+      }
+    },
+    "stopped_by": {
+      "$ref": "#/definitions/StopReason"
+    },
+    "version": {
+      "type": "integer",
+      "const": 3
+    }
+  },
+  "additionalProperties": false,
+  "definitions": {
+    "FillCommit": {
+      "type": "string",
+      "enum": [
+        "enter",
+        "suggestion",
+        "blur"
+      ]
+    },
+    "KeyModifier": {
+      "description": "Keyboard modifier flags. Multiple flags may be combined; the extension folds them into CDP's bitfield (`alt=1, ctrl=2, meta=4, shift=8`).",
+      "type": "string",
+      "enum": [
+        "alt",
+        "ctrl",
+        "meta",
+        "shift"
+      ]
+    },
+    "NavigationCause": {
+      "type": "string",
+      "enum": [
+        "user_typed",
+        "link",
+        "form_submit",
+        "reload",
+        "history",
+        "script",
+        "browser"
+      ]
+    },
+    "RecorderInfo": {
+      "type": "object",
+      "required": [
+        "bsk",
+        "vom"
+      ],
+      "properties": {
+        "bsk": {
+          "type": "string"
+        },
+        "vom": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        }
+      }
+    },
+    "SelectedOptionV3": {
+      "description": "One selected option (`select` op).",
+      "type": "object",
+      "required": [
+        "value"
+      ],
+      "properties": {
+        "label": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "value": {
+          "type": "string"
+        }
+      }
+    },
+    "StepResultV3": {
+      "type": "object",
+      "required": [
+        "state"
+      ],
+      "properties": {
+        "state": {
+          "type": "string"
+        }
+      }
+    },
+    "StepV3": {
+      "description": "One recorded user action — discriminated union by `op`.",
+      "oneOf": [
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "cause",
+            "id",
+            "op",
+            "result",
+            "state",
+            "to"
+          ],
+          "properties": {
+            "cause": {
+              "$ref": "#/definitions/NavigationCause"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "navigate"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "to": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "click"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "hover"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "commit",
+            "id",
+            "op",
+            "result",
+            "state",
+            "target",
+            "value"
+          ],
+          "properties": {
+            "commit": {
+              "$ref": "#/definitions/FillCommit"
+            },
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "fill"
+              ]
+            },
+            "redacted": {
+              "type": "boolean"
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            },
+            "value": {
+              "type": "string"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state",
+            "target"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "select"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "selection": {
+              "type": "array",
+              "items": {
+                "$ref": "#/definitions/SelectedOptionV3"
+              }
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "$ref": "#/definitions/TargetDescriptorV3"
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "key",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "key": {
+              "type": "string"
+            },
+            "modifiers": {
+              "type": [
+                "array",
+                "null"
+              ],
+              "items": {
+                "$ref": "#/definitions/KeyModifier"
+              }
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "press"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            },
+            "target": {
+              "anyOf": [
+                {
+                  "$ref": "#/definitions/TargetDescriptorV3"
+                },
+                {
+                  "type": "null"
+                }
+              ]
+            }
+          }
+        },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "scroll"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
+        }
+      ]
+    },
+    "StopReason": {
+      "type": "string",
+      "enum": [
+        "user_finish",
+        "cli_stop"
+      ]
+    },
+    "TargetDescriptorV3": {
+      "description": "Stable semantic handle for an interacted element within a page observation.",
+      "type": "object",
+      "properties": {
+        "ctx": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "name": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "ref": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "role": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "unmatched": {
+          "type": "boolean"
+        }
+      }
+    },
+    "TraceEntry": {
+      "type": "object",
+      "required": [
+        "start_url"
+      ],
+      "properties": {
+        "start_url": {
+          "type": "string"
+        }
+      }
+    },
+    "TraceStateV3": {
+      "description": "Page observation dictionary entry — referenced by steps via `state` / `result.state`.",
+      "type": "object",
+      "required": [
+        "body",
+        "id",
+        "url"
+      ],
+      "properties": {
+        "body": {
+          "description": "Full page observation (front matter + VOM body + annotations).",
+          "type": "string"
+        },
+        "id": {
+          "type": "string"
+        },
+        "title": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "truncated": {
+          "type": "boolean"
+        },
+        "url": {
+          "type": "string"
+        }
+      }
+    }
+  }
+}

crates/bsk-protocol/src/bin/dump-schema.rs

@@ -113,8 +113,12 @@ fn main() {
     dump!(RequestHelpParams, "tool_request_help_params");
     dump!(RequestHelpResult, "tool_request_help_result");
 
-    dump!(Trace, "trace");
-    dump!(Step, "trace_step");
+    dump!(TraceV2, "trace_v2");
+    dump!(TraceV3, "trace_v3");
+    dump!(RecordedTrace, "trace");
+    dump!(StepV2, "trace_step_v2");
+    dump!(StepV3, "trace_step_v3");
+    dump!(RecordedStep, "trace_step");
     dump!(RecordStartParams, "tool_record_start_params");
     dump!(RecordStartResult, "tool_record_start_result");
     dump!(RecordStopParams, "tool_record_stop_params");

crates/bsk-protocol/src/tools/mod.rs

@@ -9,6 +9,9 @@ pub mod navigation;
 pub mod network;
 pub mod observation;
 pub mod record;
+mod record_common;
+mod record_v2;
+mod record_v3;
 pub mod script;
 pub mod session;
 pub mod tabs;

crates/bsk-protocol/src/tools/record.rs

@@ -1,147 +1,23 @@
 //! Semantic user-action recording (`tool.record_start` / `stop` / `await`).
 //!
-//! Trace v2 is a **record-only** log of user actions: what was clicked, filled,
-//! selected, and where navigation occurred. No LLM runs during recording, so
-//! variable-vs-constant classification is **not** stored — executing agents
-//! infer that at run time from raw values and control names.
+//! Wire traces are either Trace v2 (`pages[]`) or Trace v3 (`version: 3`,
+//! `states[]`). Version-specific models live in `record_v2` / `record_v3`.
 
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
 
-use super::interaction::KeyModifier;
+pub use super::record_common::TraceEntry;
+pub use super::record_v2::{
+    PageRefV2, SelectedOptionV2, StepCommonV2, StepEffectV2, StepV2, TargetDescriptorV2, TraceV2,
+};
+pub use super::record_v3::{
+    FillCommit, NavigationCause, RecorderInfo, SelectedOptionV3, StepCommonV3, StepResultV3,
+    StepV3, StopReason, TRACE_VERSION_V3, TargetDescriptorV3, TraceStateV3, TraceV3,
+    VOM_FORMAT_VERSION,
+};
 
-// ---------------------------------------------------------------------------
-// Target
-// ---------------------------------------------------------------------------
-
-/// Stable semantic handle for an interacted element.
-///
-/// `name` and `nearby_label` are **untrusted page text**.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-pub struct TargetDescriptor {
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub role: Option<String>,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub name: Option<String>,
-    pub tag: String,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub name_attr: Option<String>,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub placeholder: Option<String>,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub nearby_label: Option<String>,
-}
-
-// ---------------------------------------------------------------------------
-// Trace envelope
-// ---------------------------------------------------------------------------
-
-/// Recording entry point — first URL the flow starts from.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-pub struct TraceEntry {
-    pub start_url: String,
-}
-
-/// Page context dictionary entry — referenced by steps via `page` id.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-pub struct PageRef {
-    pub id: String,
-    pub url: String,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub title: Option<String>,
-}
-
-/// One selected option (`select` op).
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-pub struct SelectedOption {
-    pub value: String,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub label: Option<String>,
-}
-
-/// Observed navigation after a step (objective fact only).
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-pub struct StepEffect {
-    /// Reference into `pages[]` for the destination page.
-    pub navigated_to: String,
-}
-
-/// Fields shared by every step variant (flattened in JSON).
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-pub struct StepCommon {
-    pub id: u32,
-    /// Reference into `pages[]`.
-    pub page: String,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub effect: Option<StepEffect>,
-}
-
-// ---------------------------------------------------------------------------
-// Step op-specific payloads
-// ---------------------------------------------------------------------------
-
-/// One recorded user action — discriminated union by `op`.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-#[serde(tag = "op", rename_all = "snake_case")]
-pub enum Step {
-    Navigate {
-        #[serde(flatten)]
-        common: StepCommon,
-        to: String,
-    },
-    Click {
-        #[serde(flatten)]
-        common: StepCommon,
-        target: TargetDescriptor,
-    },
-    Hover {
-        #[serde(flatten)]
-        common: StepCommon,
-        target: TargetDescriptor,
-    },
-    Fill {
-        #[serde(flatten)]
-        common: StepCommon,
-        target: TargetDescriptor,
-        value: String,
-        #[serde(default, skip_serializing_if = "Option::is_none")]
-        redacted: Option<bool>,
-    },
-    Select {
-        #[serde(flatten)]
-        common: StepCommon,
-        target: TargetDescriptor,
-        selection: Vec<SelectedOption>,
-    },
-    Press {
-        #[serde(flatten)]
-        common: StepCommon,
-        key: String,
-        #[serde(default, skip_serializing_if = "Option::is_none")]
-        modifiers: Option<Vec<KeyModifier>>,
-        #[serde(default, skip_serializing_if = "Option::is_none")]
-        target: Option<TargetDescriptor>,
-    },
-}
-
-// ---------------------------------------------------------------------------
-// Trace root
-// ---------------------------------------------------------------------------
-
-/// Persisted user-action trace exported by `tool.record_stop` / `await`.
-#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
-pub struct Trace {
-    /// RFC 3339 timestamp when recording stopped.
-    pub recorded_at: String,
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub started_at: Option<String>,
-    /// Optional user-provided goal from `--purpose` (metadata only).
-    #[serde(default, skip_serializing_if = "Option::is_none")]
-    pub purpose: Option<String>,
-    pub entry: TraceEntry,
-    pub pages: Vec<PageRef>,
-    pub steps: Vec<Step>,
-}
+/// Logical v2 identifier. Not a wire field — v2 envelopes omit `version`.
+pub const TRACE_VERSION_V2: u32 = 2;
 
 // ---------------------------------------------------------------------------
 // RPC params / results
@@ -169,9 +45,209 @@ pub struct RecordStopParams {
     pub session_id: String,
 }
 
+/// Wire trace payload — v2 (legacy `pages[]`) or v3 (`version: 3`, `states[]`).
+///
+/// Classification matches [`RecordedTrace::classify_value`]: a numeric `version`
+/// selects v3 (and forbids `pages[]`); otherwise the envelope is v2 and must
+/// not include `states[]`.
+#[derive(Debug, Clone, PartialEq)]
+pub enum RecordedTrace {
+    V2(TraceV2),
+    V3(TraceV3),
+}
+
+impl RecordedTrace {
+    pub fn classify_value(v: &serde_json::Value) -> Result<Self, String> {
+        if let Some(ver) = v.get("version").and_then(|x| x.as_u64()) {
+            if ver != u64::from(TRACE_VERSION_V3) {
+                return Err(format!("unsupported trace version {ver}"));
+            }
+            if v.get("pages").is_some() {
+                return Err("trace v3 must not include legacy pages[]".into());
+            }
+            return serde_json::from_value(v.clone())
+                .map(RecordedTrace::V3)
+                .map_err(|e| e.to_string());
+        }
+        if v.get("states").is_some() {
+            return Err("trace v2 must not include states[]; set version: 3 for Trace v3".into());
+        }
+        if v.get("pages").is_some() {
+            return serde_json::from_value(v.clone())
+                .map(RecordedTrace::V2)
+                .map_err(|e| e.to_string());
+        }
+        Err("ambiguous or unparseable trace".into())
+    }
+}
+
+impl Serialize for RecordedTrace {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            RecordedTrace::V2(t) => t.serialize(serializer),
+            RecordedTrace::V3(t) => t.serialize(serializer),
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for RecordedTrace {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let value = serde_json::Value::deserialize(deserializer)?;
+        Self::classify_value(&value).map_err(serde::de::Error::custom)
+    }
+}
+
+impl JsonSchema for RecordedTrace {
+    fn schema_name() -> String {
+        "RecordedTrace".into()
+    }
+
+    fn json_schema(generator: &mut schemars::SchemaGenerator) -> schemars::schema::Schema {
+        // Mirror classify_value: a numeric `version` selects v3; otherwise v2.
+        // TraceV2 stays open for unknown extension fields but forbids `states[]`
+        // and a numeric `version`. TraceV3 already denies `pages[]`.
+        let mut version_props = schemars::Map::new();
+        version_props.insert(
+            "version".into(),
+            schemars::schema::SchemaObject {
+                instance_type: Some(schemars::schema::InstanceType::Integer.into()),
+                ..Default::default()
+            }
+            .into(),
+        );
+        let mut required = schemars::Set::new();
+        required.insert("version".into());
+
+        schemars::schema::SchemaObject {
+            subschemas: Some(Box::new(schemars::schema::SubschemaValidation {
+                if_schema: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        object: Some(Box::new(schemars::schema::ObjectValidation {
+                            properties: version_props,
+                            required,
+                            ..Default::default()
+                        })),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
+                then_schema: Some(Box::new(generator.subschema_for::<TraceV3>())),
+                else_schema: Some(Box::new(generator.subschema_for::<TraceV2>())),
+                ..Default::default()
+            })),
+            ..Default::default()
+        }
+        .into()
+    }
+}
+
+/// One recorded step — v2 (`page`) or v3 (`state` / `result.state`).
+///
+/// Classification matches [`RecordedStep::classify_value`]: `state` selects v3
+/// (and forbids `page`); otherwise the step is v2 and must include `page`.
+#[derive(Debug, Clone, PartialEq)]
+pub enum RecordedStep {
+    V2(StepV2),
+    V3(StepV3),
+}
+
+impl RecordedStep {
+    pub fn classify_value(v: &serde_json::Value) -> Result<Self, String> {
+        if v.get("state").is_some() {
+            if v.get("page").is_some() {
+                return Err("step v3 must not include legacy page".into());
+            }
+            return serde_json::from_value(v.clone())
+                .map(RecordedStep::V3)
+                .map_err(|e| e.to_string());
+        }
+        if v.get("page").is_some() {
+            return serde_json::from_value(v.clone())
+                .map(RecordedStep::V2)
+                .map_err(|e| e.to_string());
+        }
+        Err("ambiguous or unparseable step".into())
+    }
+}
+
+impl Serialize for RecordedStep {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: serde::Serializer,
+    {
+        match self {
+            RecordedStep::V2(s) => s.serialize(serializer),
+            RecordedStep::V3(s) => s.serialize(serializer),
+        }
+    }
+}
+
+impl<'de> Deserialize<'de> for RecordedStep {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        let value = serde_json::Value::deserialize(deserializer)?;
+        Self::classify_value(&value).map_err(serde::de::Error::custom)
+    }
+}
+
+impl JsonSchema for RecordedStep {
+    fn schema_name() -> String {
+        "RecordedStep".into()
+    }
+
+    fn json_schema(generator: &mut schemars::SchemaGenerator) -> schemars::schema::Schema {
+        // Mirror classify_value: `state` selects v3; otherwise v2.
+        // Mixed page + state is rejected at this layer because StepV2/StepV3
+        // still allow unknown extension fields.
+        let mut required = schemars::Set::new();
+        required.insert("state".into());
+        let mut mixed_keys = schemars::Set::new();
+        mixed_keys.insert("page".into());
+        mixed_keys.insert("state".into());
+
+        schemars::schema::SchemaObject {
+            subschemas: Some(Box::new(schemars::schema::SubschemaValidation {
+                if_schema: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        object: Some(Box::new(schemars::schema::ObjectValidation {
+                            required,
+                            ..Default::default()
+                        })),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
+                then_schema: Some(Box::new(generator.subschema_for::<StepV3>())),
+                else_schema: Some(Box::new(generator.subschema_for::<StepV2>())),
+                not: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        object: Some(Box::new(schemars::schema::ObjectValidation {
+                            required: mixed_keys,
+                            ..Default::default()
+                        })),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
+                ..Default::default()
+            })),
+            ..Default::default()
+        }
+        .into()
+    }
+}
+
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
 pub struct RecordStopResult {
-    pub trace: Trace,
+    pub trace: RecordedTrace,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
@@ -183,281 +259,197 @@ pub struct RecordAwaitParams {
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
 pub struct RecordAwaitResult {
-    pub trace: Trace,
+    pub trace: RecordedTrace,
 }
 
-// ---------------------------------------------------------------------------
-// Tests
-// ---------------------------------------------------------------------------
-
 #[cfg(test)]
 mod tests {
     use super::*;
     use serde_json::json;
 
-    fn sample_common(id: u32) -> StepCommon {
-        StepCommon {
-            id,
-            page: "p1".into(),
-            effect: None,
+    #[test]
+    fn recorded_trace_classifies_v2_and_v3() {
+        let v2 = json!({
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "entry": { "start_url": "https://example.com/" },
+            "pages": [{ "id": "p1", "url": "https://example.com/" }],
+            "steps": []
+        });
+        match RecordedTrace::classify_value(&v2).unwrap() {
+            RecordedTrace::V2(_) => {}
+            other => panic!("expected v2, got {other:?}"),
         }
-    }
 
-    fn sample_target() -> TargetDescriptor {
-        TargetDescriptor {
-            role: Some("button".into()),
-            name: Some("发布".into()),
-            tag: "button".into(),
-            name_attr: None,
-            placeholder: None,
-            nearby_label: None,
-        }
-    }
-
-    fn sample_trace() -> Trace {
-        Trace {
-            recorded_at: "2026-07-17T09:01:10Z".into(),
-            started_at: Some("2026-07-17T09:00:00Z".into()),
-            purpose: Some("发布一篇文章".into()),
-            entry: TraceEntry {
-                start_url: "https://x.com/editor".into(),
-            },
-            pages: vec![
-                PageRef {
-                    id: "p1".into(),
-                    url: "https://x.com/editor".into(),
-                    title: Some("写文章".into()),
-                },
-                PageRef {
-                    id: "p2".into(),
-                    url: "https://x.com/p/99".into(),
-                    title: None,
-                },
-            ],
-            steps: vec![
-                Step::Fill {
-                    common: sample_common(1),
-                    target: TargetDescriptor {
-                        role: Some("textbox".into()),
-                        name: Some("标题".into()),
-                        tag: "input".into(),
-                        name_attr: None,
-                        placeholder: None,
-                        nearby_label: None,
-                    },
-                    value: "我的第一篇文章".into(),
-                    redacted: None,
-                },
-                Step::Select {
-                    common: sample_common(3),
-                    target: TargetDescriptor {
-                        role: Some("combobox".into()),
-                        name: Some("分类".into()),
-                        tag: "select".into(),
-                        name_attr: None,
-                        placeholder: None,
-                        nearby_label: None,
-                    },
-                    selection: vec![SelectedOption {
-                        value: "tech".into(),
-                        label: Some("技术分享".into()),
-                    }],
-                },
-                Step::Click {
-                    common: StepCommon {
-                        effect: Some(StepEffect {
-                            navigated_to: "p2".into(),
-                        }),
-                        ..sample_common(4)
-                    },
-                    target: sample_target(),
-                },
-            ],
+        let v3 = json!({
+            "version": 3,
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "stopped_by": "user_finish",
+            "entry": { "start_url": "https://example.com/" },
+            "recorder": { "bsk": "0.1.10", "vom": 1 },
+            "states": [],
+            "steps": []
+        });
+        match RecordedTrace::classify_value(&v3).unwrap() {
+            RecordedTrace::V3(t) => assert_eq!(t.version, 3),
+            other => panic!("expected v3, got {other:?}"),
         }
     }
 
     #[test]
-    fn step_click_round_trips() {
-        let step = Step::Click {
-            common: sample_common(1),
-            target: sample_target(),
-        };
-        let v = serde_json::to_value(&step).unwrap();
-        assert_eq!(v.get("op").and_then(|v| v.as_str()), Some("click"));
-        assert_eq!(v.get("page").and_then(|v| v.as_str()), Some("p1"));
-        assert!(v.get("key").is_none());
-        let round: Step = serde_json::from_value(v).unwrap();
-        assert_eq!(round, step);
+    fn recorded_trace_rejects_mixed_and_unsupported_versions() {
+        let v2_with_states = json!({
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "entry": { "start_url": "https://example.com/" },
+            "pages": [{ "id": "p1", "url": "https://example.com/" }],
+            "states": [],
+            "steps": []
+        });
+        assert!(RecordedTrace::classify_value(&v2_with_states).is_err());
+
+        let v3_with_pages = json!({
+            "version": 3,
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "stopped_by": "user_finish",
+            "entry": { "start_url": "https://example.com/" },
+            "recorder": { "bsk": "0.1.10", "vom": 1 },
+            "pages": [{ "id": "p1", "url": "https://example.com/" }],
+            "states": [],
+            "steps": []
+        });
+        assert!(RecordedTrace::classify_value(&v3_with_pages).is_err());
+
+        let unsupported = json!({
+            "version": 2,
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "stopped_by": "user_finish",
+            "entry": { "start_url": "https://example.com/" },
+            "recorder": { "bsk": "0.1.10", "vom": 1 },
+            "states": [],
+            "steps": []
+        });
+        assert!(RecordedTrace::classify_value(&unsupported).is_err());
+        assert!(serde_json::from_value::<TraceV3>(unsupported).is_err());
     }
 
-    #[test]
-    fn step_fill_with_raw_value_round_trips() {
-        let step = Step::Fill {
-            common: sample_common(2),
-            target: TargetDescriptor {
-                role: Some("textbox".into()),
-                name: Some("服务名称".into()),
-                tag: "input".into(),
-                name_attr: Some("serviceName".into()),
-                placeholder: None,
-                nearby_label: None,
-            },
-            value: "my-svc".into(),
-            redacted: None,
-        };
-        let v = serde_json::to_value(&step).unwrap();
-        assert_eq!(v["op"], "fill");
-        assert_eq!(v["value"], "my-svc");
-        let round: Step = serde_json::from_value(v).unwrap();
-        assert_eq!(round, step);
-    }
-
-    #[test]
-    fn step_fill_password_is_redacted() {
-        let step = Step::Fill {
-            common: sample_common(1),
-            target: TargetDescriptor {
-                role: Some("textbox".into()),
-                name: Some("密码".into()),
-                tag: "input".into(),
-                name_attr: None,
-                placeholder: None,
-                nearby_label: None,
-            },
-            value: "***".into(),
-            redacted: Some(true),
-        };
-        let v = serde_json::to_value(&step).unwrap();
-        assert_eq!(v["value"], "***");
-        assert_eq!(v["redacted"], true);
-    }
-
-    #[test]
-    fn step_select_uses_object_array() {
-        let step = Step::Select {
-            common: sample_common(3),
-            target: TargetDescriptor {
-                role: Some("combobox".into()),
-                name: Some("分类".into()),
-                tag: "select".into(),
-                name_attr: None,
-                placeholder: None,
-                nearby_label: None,
-            },
-            selection: vec![SelectedOption {
-                value: "tech".into(),
-                label: Some("技术分享".into()),
-            }],
-        };
-        let v = serde_json::to_value(&step).unwrap();
-        assert_eq!(v["selection"][0]["value"], "tech");
-        assert_eq!(v["selection"][0]["label"], "技术分享");
-        let round: Step = serde_json::from_value(v).unwrap();
-        assert_eq!(round, step);
-    }
-
-    #[test]
-    fn step_navigate_round_trips() {
-        let step = Step::Navigate {
-            common: sample_common(1),
-            to: "https://example.com".into(),
-        };
-        let v = serde_json::to_value(&step).unwrap();
-        assert_eq!(v["op"], "navigate");
-        assert_eq!(v["to"], "https://example.com");
-        let round: Step = serde_json::from_value(v).unwrap();
-        assert_eq!(round, step);
-    }
-
-    #[test]
-    fn step_press_with_modifiers_round_trips() {
-        let step = Step::Press {
-            common: StepCommon {
-                effect: Some(StepEffect {
-                    navigated_to: "p2".into(),
-                }),
-                ..sample_common(2)
-            },
-            key: "Enter".into(),
-            modifiers: Some(vec![KeyModifier::Ctrl, KeyModifier::Shift]),
-            target: Some(sample_target()),
-        };
-        let v = serde_json::to_value(&step).unwrap();
-        assert_eq!(v["key"], "Enter");
-        assert_eq!(v["modifiers"], json!(["ctrl", "shift"]));
-        assert_eq!(v["effect"]["navigated_to"], "p2");
-        let round: Step = serde_json::from_value(v).unwrap();
-        assert_eq!(round, step);
-    }
-
-    #[test]
-    fn trace_record_only_round_trips() {
-        let trace = sample_trace();
-        let v = serde_json::to_value(&trace).unwrap();
-        assert!(v.get("version").is_none());
+    fn assert_classifies_by_integer_version(schema: &serde_json::Value) {
         assert_eq!(
-            v.get("purpose").and_then(|v| v.as_str()),
-            Some("发布一篇文章")
+            schema["if"]["required"],
+            json!(["version"]),
+            "numeric version is the RecordedTrace classification key"
         );
-        assert!(v.get("parameters").is_none());
-        assert!(v.get("site").is_none());
-        assert!(v.get("goal").is_none());
-        assert_eq!(
-            v.get("entry")
-                .and_then(|e| e.get("start_url"))
-                .and_then(|u| u.as_str()),
-            Some("https://x.com/editor")
-        );
-        let round: Trace = serde_json::from_value(v).unwrap();
-        assert_eq!(round, trace);
+        assert_eq!(schema["if"]["properties"]["version"]["type"], "integer");
+        assert_eq!(schema["then"]["$ref"], "#/definitions/TraceV3");
+        assert_eq!(schema["else"]["$ref"], "#/definitions/TraceV2");
     }
 
     #[test]
-    fn discriminated_union_click_ignores_extra_key_field() {
-        let bad = json!({
+    fn recorded_trace_schema_includes_v2_and_v3() {
+        let schema = serde_json::to_value(schemars::schema_for!(RecordStopResult)).unwrap();
+        assert_classifies_by_integer_version(&schema["definitions"]["RecordedTrace"]);
+        assert_eq!(
+            schema["definitions"]["TraceV3"]["properties"]["version"]["const"],
+            3
+        );
+    }
+
+    #[test]
+    fn recorded_trace_schema_follows_classify_value() {
+        let standalone = serde_json::to_value(schemars::schema_for!(RecordedTrace)).unwrap();
+        assert_classifies_by_integer_version(&standalone);
+        assert!(standalone["definitions"].get("TraceV2").is_some());
+        assert!(standalone["definitions"].get("TraceV3").is_some());
+
+        let stop_result = serde_json::to_value(schemars::schema_for!(RecordStopResult)).unwrap();
+        assert_classifies_by_integer_version(&stop_result["definitions"]["RecordedTrace"]);
+    }
+
+    #[test]
+    fn standalone_trace_schema_is_recorded_trace_union() {
+        let schema = serde_json::to_value(schemars::schema_for!(RecordedTrace)).unwrap();
+        assert_eq!(schema["title"], "RecordedTrace");
+        assert_classifies_by_integer_version(&schema);
+        assert!(schema["definitions"].get("TraceV2").is_some());
+        assert!(schema["definitions"].get("TraceV3").is_some());
+    }
+
+    #[test]
+    fn recorded_trace_accepts_v2_with_unknown_extension_fields() {
+        let v2 = json!({
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "entry": { "start_url": "https://example.com/" },
+            "pages": [{ "id": "p1", "url": "https://example.com/" }],
+            "steps": [],
+            "meta": { "tool": "legacy-exporter" }
+        });
+        match RecordedTrace::classify_value(&v2).unwrap() {
+            RecordedTrace::V2(trace) => assert_eq!(trace.pages.len(), 1),
+            other => panic!("expected v2, got {other:?}"),
+        }
+    }
+
+    fn v2_click() -> serde_json::Value {
+        json!({
             "op": "click",
             "id": 1,
             "page": "p1",
-            "target": { "tag": "button", "name": "OK" },
-            "key": "Enter"
-        });
-        let step: Step = serde_json::from_value(bad).unwrap();
-        assert!(matches!(step, Step::Click { .. }));
-        let v = serde_json::to_value(&step).unwrap();
-        assert!(v.get("key").is_none());
+            "target": { "tag": "button", "role": "button", "name": "发布" }
+        })
+    }
+
+    fn v3_click() -> serde_json::Value {
+        json!({
+            "op": "click",
+            "id": 1,
+            "state": "s1",
+            "result": { "state": "s2" },
+            "target": { "ref": "e1", "role": "button", "name": "发布" }
+        })
+    }
+
+    fn assert_step_classifies_by_state(schema: &serde_json::Value) {
+        assert_eq!(
+            schema["if"]["required"],
+            json!(["state"]),
+            "state is the RecordedStep classification key"
+        );
+        assert_eq!(schema["then"]["$ref"], "#/definitions/StepV3");
+        assert_eq!(schema["else"]["$ref"], "#/definitions/StepV2");
+        let mut forbidden = schema["not"]["required"]
+            .as_array()
+            .expect("RecordedStep schema must reject mixed page + state steps")
+            .iter()
+            .filter_map(|v| v.as_str())
+            .collect::<Vec<_>>();
+        forbidden.sort_unstable();
+        assert_eq!(forbidden, ["page", "state"]);
     }
 
     #[test]
-    fn extension_trace_deserializes() {
-        let v = json!({
-            "recorded_at": "2026-07-21T08:00:00Z",
-            "started_at": "2026-07-21T07:59:00Z",
-            "purpose": "demo",
-            "entry": { "start_url": "https://example.com/editor" },
-            "pages": [
-                { "id": "p1", "url": "https://example.com/editor" },
-                { "id": "p2", "url": "https://example.com/p/99" }
-            ],
-            "steps": [
-                {
-                    "op": "fill",
-                    "id": 1,
-                    "page": "p1",
-                    "target": { "tag": "input", "role": "textbox", "name": "标题" },
-                    "value": "hello"
-                },
-                {
-                    "op": "click",
-                    "id": 2,
-                    "page": "p1",
-                    "target": { "tag": "button", "role": "button", "name": "发布" },
-                    "effect": { "navigated_to": "p2" }
-                }
-            ]
-        });
-        let trace: Trace = serde_json::from_value(v).unwrap();
-        assert_eq!(trace.entry.start_url, "https://example.com/editor");
-        assert_eq!(trace.pages.len(), 2);
-        assert_eq!(trace.steps.len(), 2);
+    fn recorded_step_classifies_v2_and_v3() {
+        match RecordedStep::classify_value(&v2_click()).unwrap() {
+            RecordedStep::V2(StepV2::Click { .. }) => {}
+            other => panic!("expected v2 click, got {other:?}"),
+        }
+        match RecordedStep::classify_value(&v3_click()).unwrap() {
+            RecordedStep::V3(StepV3::Click { .. }) => {}
+            other => panic!("expected v3 click, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn recorded_step_rejects_mixed_page_and_state() {
+        let mut mixed = v2_click();
+        mixed["state"] = json!("s1");
+        mixed["result"] = json!({ "state": "s2" });
+        assert!(RecordedStep::classify_value(&mixed).is_err());
+    }
+
+    #[test]
+    fn recorded_step_schema_follows_classify_value() {
+        let schema = serde_json::to_value(schemars::schema_for!(RecordedStep)).unwrap();
+        assert_eq!(schema["title"], "RecordedStep");
+        assert_step_classifies_by_state(&schema);
+        assert!(schema["definitions"].get("StepV2").is_some());
+        assert!(schema["definitions"].get("StepV3").is_some());
     }
 }

crates/bsk-protocol/src/tools/record_common.rs

@@ -0,0 +1,7 @@
+use schemars::JsonSchema;
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct TraceEntry {
+    pub start_url: String,
+}

crates/bsk-protocol/src/tools/record_v2.rs

@@ -0,0 +1,330 @@
+//! Trace v2 — record-only user-action log with `pages[]` and step `page` refs.
+//!
+//! Legacy wire format with no top-level `version` field.
+
+use schemars::JsonSchema;
+use serde::{Deserialize, Serialize};
+
+use super::interaction::KeyModifier;
+use super::record_common::TraceEntry;
+
+/// Stable semantic handle for an interacted element (v2).
+///
+/// `name` and `nearby_label` are **untrusted page text**.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct TargetDescriptorV2 {
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub role: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub name: Option<String>,
+    pub tag: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub name_attr: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub placeholder: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub nearby_label: Option<String>,
+}
+
+/// Page context dictionary entry — referenced by steps via `page` id.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct PageRefV2 {
+    pub id: String,
+    pub url: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub title: Option<String>,
+}
+
+/// One selected option (`select` op).
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct SelectedOptionV2 {
+    pub value: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub label: Option<String>,
+}
+
+/// Observed navigation after a step (objective fact only).
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct StepEffectV2 {
+    /// Reference into `pages[]` for the destination page.
+    pub navigated_to: String,
+}
+
+/// Fields shared by every v2 step variant (flattened in JSON).
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct StepCommonV2 {
+    pub id: u32,
+    /// Reference into `pages[]`.
+    pub page: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub effect: Option<StepEffectV2>,
+}
+
+/// One recorded user action — discriminated union by `op` (v2).
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+#[serde(tag = "op", rename_all = "snake_case")]
+pub enum StepV2 {
+    Navigate {
+        #[serde(flatten)]
+        common: StepCommonV2,
+        to: String,
+    },
+    Click {
+        #[serde(flatten)]
+        common: StepCommonV2,
+        target: TargetDescriptorV2,
+    },
+    Hover {
+        #[serde(flatten)]
+        common: StepCommonV2,
+        target: TargetDescriptorV2,
+    },
+    Fill {
+        #[serde(flatten)]
+        common: StepCommonV2,
+        target: TargetDescriptorV2,
+        value: String,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        redacted: Option<bool>,
+    },
+    Select {
+        #[serde(flatten)]
+        common: StepCommonV2,
+        target: TargetDescriptorV2,
+        selection: Vec<SelectedOptionV2>,
+    },
+    Press {
+        #[serde(flatten)]
+        common: StepCommonV2,
+        key: String,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        modifiers: Option<Vec<KeyModifier>>,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        target: Option<TargetDescriptorV2>,
+    },
+}
+
+/// Persisted user-action trace exported by legacy `tool.record_stop` / `await`.
+///
+/// Unknown extension fields are ignored so older traces remain readable.
+/// `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace`
+/// classification — serde still ignores them, but the JSON Schema rejects them.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+pub struct TraceV2 {
+    /// RFC 3339 timestamp when recording stopped.
+    pub recorded_at: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub started_at: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub purpose: Option<String>,
+    pub entry: TraceEntry,
+    pub pages: Vec<PageRefV2>,
+    pub steps: Vec<StepV2>,
+}
+
+fn constrain_trace_v2_schema(mut schema: schemars::schema::Schema) -> schemars::schema::Schema {
+    let schemars::schema::Schema::Object(obj) = &mut schema else {
+        return schema;
+    };
+    obj.metadata().title = Some("TraceV2".into());
+    obj.metadata().description = Some(
+        "Persisted user-action trace exported by legacy `tool.record_stop` / `await`.\n\n\
+         Unknown extension fields are ignored so older traces remain readable. \
+         `states[]` and a numeric `version` are reserved for Trace v3 / `RecordedTrace` classification."
+            .into(),
+    );
+
+    let object = obj.object.get_or_insert_with(Default::default);
+    object
+        .properties
+        .insert("states".into(), schemars::schema::Schema::Bool(false));
+    object.properties.insert(
+        "version".into(),
+        schemars::schema::SchemaObject {
+            metadata: Some(Box::new(schemars::schema::Metadata {
+                description: Some(
+                    "Numeric version selects Trace v3. Legacy v2 envelopes omit this field.".into(),
+                ),
+                ..Default::default()
+            })),
+            subschemas: Some(Box::new(schemars::schema::SubschemaValidation {
+                not: Some(Box::new(
+                    schemars::schema::SchemaObject {
+                        instance_type: Some(schemars::schema::InstanceType::Integer.into()),
+                        ..Default::default()
+                    }
+                    .into(),
+                )),
+                ..Default::default()
+            })),
+            ..Default::default()
+        }
+        .into(),
+    );
+    schema
+}
+
+impl JsonSchema for TraceV2 {
+    fn schema_name() -> String {
+        "TraceV2".into()
+    }
+
+    fn json_schema(generator: &mut schemars::SchemaGenerator) -> schemars::schema::Schema {
+        #[derive(JsonSchema)]
+        #[allow(dead_code)]
+        struct TraceV2Shape {
+            /// RFC 3339 timestamp when recording stopped.
+            recorded_at: String,
+            started_at: Option<String>,
+            purpose: Option<String>,
+            entry: TraceEntry,
+            pages: Vec<PageRefV2>,
+            steps: Vec<StepV2>,
+        }
+
+        constrain_trace_v2_schema(TraceV2Shape::json_schema(generator))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json::json;
+
+    fn sample_common(id: u32) -> StepCommonV2 {
+        StepCommonV2 {
+            id,
+            page: "p1".into(),
+            effect: None,
+        }
+    }
+
+    fn sample_target() -> TargetDescriptorV2 {
+        TargetDescriptorV2 {
+            role: Some("button".into()),
+            name: Some("发布".into()),
+            tag: "button".into(),
+            name_attr: None,
+            placeholder: None,
+            nearby_label: None,
+        }
+    }
+
+    #[test]
+    fn trace_v2_has_no_version_field() {
+        let trace = TraceV2 {
+            recorded_at: "2026-07-17T09:01:10Z".into(),
+            started_at: None,
+            purpose: None,
+            entry: TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            pages: vec![PageRefV2 {
+                id: "p1".into(),
+                url: "https://example.com/".into(),
+                title: None,
+            }],
+            steps: vec![StepV2::Click {
+                common: sample_common(1),
+                target: sample_target(),
+            }],
+        };
+        let v = serde_json::to_value(&trace).unwrap();
+        assert!(v.get("version").is_none());
+        assert!(v.get("pages").is_some());
+        assert!(v.get("states").is_none());
+    }
+
+    #[test]
+    fn extension_v2_trace_deserializes() {
+        let v = json!({
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "started_at": "2026-07-21T07:59:00Z",
+            "purpose": "demo",
+            "entry": { "start_url": "https://example.com/editor" },
+            "pages": [
+                { "id": "p1", "url": "https://example.com/editor" },
+                { "id": "p2", "url": "https://example.com/p/99" }
+            ],
+            "steps": [
+                {
+                    "op": "fill",
+                    "id": 1,
+                    "page": "p1",
+                    "target": { "tag": "input", "role": "textbox", "name": "标题" },
+                    "value": "hello"
+                },
+                {
+                    "op": "click",
+                    "id": 2,
+                    "page": "p1",
+                    "target": { "tag": "button", "role": "button", "name": "发布" },
+                    "effect": { "navigated_to": "p2" }
+                }
+            ]
+        });
+        let trace: TraceV2 = serde_json::from_value(v).unwrap();
+        assert_eq!(trace.pages.len(), 2);
+        assert_eq!(trace.steps.len(), 2);
+    }
+
+    #[test]
+    fn v2_hover_steps_round_trip() {
+        let value = json!({
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "entry": { "start_url": "https://example.com/" },
+            "pages": [{ "id": "p1", "url": "https://example.com/" }],
+            "steps": [{
+                "op": "hover",
+                "id": 1,
+                "page": "p1",
+                "target": { "tag": "span", "role": "button", "name": "Account" }
+            }]
+        });
+
+        let trace: TraceV2 = serde_json::from_value(value).unwrap();
+        assert!(matches!(trace.steps.as_slice(), [StepV2::Hover { .. }]));
+        assert_eq!(
+            serde_json::to_value(&trace).unwrap()["steps"][0]["op"],
+            "hover"
+        );
+    }
+
+    #[test]
+    fn trace_v2_ignores_unknown_extension_fields() {
+        let value = json!({
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "entry": { "start_url": "https://example.com/" },
+            "pages": [{ "id": "p1", "url": "https://example.com/" }],
+            "steps": [],
+            "meta": { "tool": "legacy-exporter" }
+        });
+        let trace: TraceV2 = serde_json::from_value(value).unwrap();
+        assert_eq!(trace.pages.len(), 1);
+        assert!(trace.steps.is_empty());
+    }
+
+    #[test]
+    fn trace_v2_schema_allows_additional_properties() {
+        let schema = serde_json::to_value(schemars::schema_for!(TraceV2)).unwrap();
+        assert_ne!(
+            schema.get("additionalProperties"),
+            Some(&serde_json::Value::Bool(false)),
+            "Trace v2 must keep accepting traces with unknown extension fields"
+        );
+    }
+
+    #[test]
+    fn trace_v2_schema_forbids_classification_keys() {
+        let schema = serde_json::to_value(schemars::schema_for!(TraceV2)).unwrap();
+        assert_eq!(
+            schema["properties"]["states"],
+            json!(false),
+            "Trace v2 schema must reject states[] (reserved for v3)"
+        );
+        assert_eq!(
+            schema["properties"]["version"]["not"]["type"], "integer",
+            "Trace v2 schema must reject a numeric version (that selects the v3 path)"
+        );
+    }
+}

crates/bsk-protocol/src/tools/record_v3.rs

@@ -0,0 +1,428 @@
+//! Trace v3 — state-action-state log with `states[]` and step `state` refs.
+//!
+//! Wire format with top-level `version: 3`.
+
+use schemars::JsonSchema;
+use serde::{Deserialize, Deserializer, Serialize};
+
+use super::interaction::KeyModifier;
+use super::record_common::TraceEntry;
+
+pub const TRACE_VERSION_V3: u32 = 3;
+pub const VOM_FORMAT_VERSION: u32 = 1;
+
+fn deserialize_trace_v3_version<'de, D>(deserializer: D) -> Result<u32, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    let version = u32::deserialize(deserializer)?;
+    if version != TRACE_VERSION_V3 {
+        return Err(serde::de::Error::custom(format!(
+            "unsupported trace version {version} (expected {TRACE_VERSION_V3})"
+        )));
+    }
+    Ok(version)
+}
+
+fn trace_v3_version_schema(_: &mut schemars::r#gen::SchemaGenerator) -> schemars::schema::Schema {
+    schemars::schema::SchemaObject {
+        instance_type: Some(schemars::schema::InstanceType::Integer.into()),
+        const_value: Some(serde_json::json!(TRACE_VERSION_V3)),
+        ..Default::default()
+    }
+    .into()
+}
+
+/// Stable semantic handle for an interacted element within a page observation.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct TargetDescriptorV3 {
+    #[serde(default, skip_serializing_if = "Option::is_none", rename = "ref")]
+    pub element_ref: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub role: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub name: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub ctx: Option<String>,
+    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+    pub unmatched: bool,
+}
+
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct RecorderInfo {
+    pub bsk: String,
+    pub vom: u32,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum StopReason {
+    UserFinish,
+    CliStop,
+}
+
+/// Page observation dictionary entry — referenced by steps via `state` / `result.state`.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct TraceStateV3 {
+    pub id: String,
+    pub url: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub title: Option<String>,
+    /// Full page observation (front matter + VOM body + annotations).
+    pub body: String,
+    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+    pub truncated: bool,
+}
+
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct StepResultV3 {
+    pub state: String,
+}
+
+/// Fields shared by every step variant (flattened in JSON).
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct StepCommonV3 {
+    pub id: u32,
+    /// Observation id immediately before this action.
+    pub state: String,
+    pub result: StepResultV3,
+}
+
+/// One selected option (`select` op).
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+pub struct SelectedOptionV3 {
+    pub value: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub label: Option<String>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum NavigationCause {
+    UserTyped,
+    Link,
+    FormSubmit,
+    Reload,
+    History,
+    Script,
+    Browser,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum FillCommit {
+    Enter,
+    Suggestion,
+    Blur,
+}
+
+/// One recorded user action — discriminated union by `op`.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+#[serde(tag = "op", rename_all = "snake_case")]
+pub enum StepV3 {
+    Navigate {
+        #[serde(flatten)]
+        common: StepCommonV3,
+        to: String,
+        cause: NavigationCause,
+    },
+    Click {
+        #[serde(flatten)]
+        common: StepCommonV3,
+        target: TargetDescriptorV3,
+    },
+    Hover {
+        #[serde(flatten)]
+        common: StepCommonV3,
+        target: TargetDescriptorV3,
+    },
+    Fill {
+        #[serde(flatten)]
+        common: StepCommonV3,
+        target: TargetDescriptorV3,
+        value: String,
+        commit: FillCommit,
+        #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+        redacted: bool,
+    },
+    Select {
+        #[serde(flatten)]
+        common: StepCommonV3,
+        target: TargetDescriptorV3,
+        #[serde(default, skip_serializing_if = "Vec::is_empty")]
+        selection: Vec<SelectedOptionV3>,
+    },
+    Press {
+        #[serde(flatten)]
+        common: StepCommonV3,
+        key: String,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        modifiers: Option<Vec<KeyModifier>>,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        target: Option<TargetDescriptorV3>,
+    },
+    Scroll {
+        #[serde(flatten)]
+        common: StepCommonV3,
+    },
+}
+
+/// Wire trace returned by `tool.record_stop` / `await`.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
+#[serde(deny_unknown_fields)]
+pub struct TraceV3 {
+    #[serde(deserialize_with = "deserialize_trace_v3_version")]
+    #[schemars(schema_with = "trace_v3_version_schema")]
+    pub version: u32,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub purpose: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub started_at: Option<String>,
+    pub recorded_at: String,
+    pub stopped_by: StopReason,
+    pub entry: TraceEntry,
+    pub recorder: RecorderInfo,
+    pub states: Vec<TraceStateV3>,
+    pub steps: Vec<StepV3>,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use serde_json::json;
+
+    fn sample_common(id: u32, state: &str, result_state: &str) -> StepCommonV3 {
+        StepCommonV3 {
+            id,
+            state: state.into(),
+            result: StepResultV3 {
+                state: result_state.into(),
+            },
+        }
+    }
+
+    fn sample_target() -> TargetDescriptorV3 {
+        TargetDescriptorV3 {
+            element_ref: Some("e21".into()),
+            role: Some("button".into()),
+            name: Some("发布".into()),
+            ctx: Some("金桔柠檬 6 号".into()),
+            unmatched: false,
+        }
+    }
+
+    fn sample_trace() -> TraceV3 {
+        TraceV3 {
+            version: TRACE_VERSION_V3,
+            purpose: Some("把草稿商品发布上架".into()),
+            started_at: Some("2026-08-10T02:10:41.080Z".into()),
+            recorded_at: "2026-08-10T02:12:55.360Z".into(),
+            stopped_by: StopReason::UserFinish,
+            entry: TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            recorder: RecorderInfo {
+                bsk: "0.1.10".into(),
+                vom: VOM_FORMAT_VERSION,
+            },
+            states: vec![
+                TraceStateV3 {
+                    id: "s1".into(),
+                    url: "https://example.com/".into(),
+                    title: Some("Example Domain".into()),
+                    body: "@vom 1\nRootWebArea \"Example Domain\"".into(),
+                    truncated: false,
+                },
+                TraceStateV3 {
+                    id: "s2".into(),
+                    url: "https://shop.example.com/products?status=draft".into(),
+                    title: Some("商品管理".into()),
+                    body: "@vom 1\nRootWebArea \"商品管理\"".into(),
+                    truncated: false,
+                },
+            ],
+            steps: vec![
+                StepV3::Navigate {
+                    common: sample_common(1, "s1", "s2"),
+                    to: "https://shop.example.com/products?status=draft".into(),
+                    cause: NavigationCause::UserTyped,
+                },
+                StepV3::Fill {
+                    common: sample_common(2, "s2", "s2"),
+                    target: TargetDescriptorV3 {
+                        element_ref: Some("e12".into()),
+                        role: Some("textbox".into()),
+                        name: Some("搜索商品".into()),
+                        ctx: None,
+                        unmatched: false,
+                    },
+                    value: "金桔柠檬".into(),
+                    commit: FillCommit::Enter,
+                    redacted: false,
+                },
+                StepV3::Click {
+                    common: sample_common(3, "s2", "s2"),
+                    target: sample_target(),
+                },
+            ],
+        }
+    }
+
+    #[test]
+    fn step_click_round_trips() {
+        let step = StepV3::Click {
+            common: sample_common(1, "s1", "s2"),
+            target: sample_target(),
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v.get("op").and_then(|v| v.as_str()), Some("click"));
+        assert_eq!(v.get("state").and_then(|v| v.as_str()), Some("s1"));
+        assert_eq!(v["result"]["state"], "s2");
+        assert_eq!(v["target"]["ref"], "e21");
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
+    #[test]
+    fn step_fill_with_commit_round_trips() {
+        let step = StepV3::Fill {
+            common: sample_common(2, "s2", "s3"),
+            target: TargetDescriptorV3 {
+                element_ref: Some("e12".into()),
+                role: Some("textbox".into()),
+                name: Some("搜索商品".into()),
+                ctx: None,
+                unmatched: false,
+            },
+            value: "browser skill".into(),
+            commit: FillCommit::Enter,
+            redacted: false,
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["op"], "fill");
+        assert_eq!(v["commit"], "enter");
+        assert!(v.get("redacted").is_none());
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
+    #[test]
+    fn step_fill_password_is_redacted() {
+        let step = StepV3::Fill {
+            common: sample_common(1, "s1", "s1"),
+            target: TargetDescriptorV3 {
+                element_ref: Some("e3".into()),
+                role: Some("textbox".into()),
+                name: Some("密码".into()),
+                ctx: None,
+                unmatched: false,
+            },
+            value: "***".into(),
+            commit: FillCommit::Blur,
+            redacted: true,
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["value"], "***");
+        assert_eq!(v["redacted"], true);
+    }
+
+    #[test]
+    fn step_navigate_with_cause_round_trips() {
+        let step = StepV3::Navigate {
+            common: sample_common(1, "s1", "s2"),
+            to: "https://example.com".into(),
+            cause: NavigationCause::UserTyped,
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["op"], "navigate");
+        assert_eq!(v["cause"], "user_typed");
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
+    #[test]
+    fn trace_v3_round_trips() {
+        let trace = sample_trace();
+        let v = serde_json::to_value(&trace).unwrap();
+        assert_eq!(v.get("version").and_then(|v| v.as_u64()), Some(3));
+        assert!(v.get("pages").is_none());
+        assert_eq!(v["recorder"]["vom"], 1);
+        assert_eq!(v["states"].as_array().unwrap().len(), 2);
+        let round: TraceV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, trace);
+    }
+
+    #[test]
+    fn default_fields_are_omitted() {
+        let step = StepV3::Click {
+            common: sample_common(1, "s1", "s1"),
+            target: TargetDescriptorV3 {
+                element_ref: Some("e1".into()),
+                role: Some("button".into()),
+                name: Some("OK".into()),
+                ctx: None,
+                unmatched: false,
+            },
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert!(v.get("unmatched").is_none());
+        assert!(v["target"].get("ctx").is_none());
+        assert!(v["target"].get("unmatched").is_none());
+    }
+
+    #[test]
+    fn unmatched_target_serializes_flag() {
+        let step = StepV3::Click {
+            common: sample_common(1, "s1", "s2"),
+            target: TargetDescriptorV3 {
+                element_ref: None,
+                role: Some("button".into()),
+                name: Some("发布".into()),
+                ctx: None,
+                unmatched: true,
+            },
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["target"]["unmatched"], true);
+        assert!(v["target"].get("ref").is_none());
+    }
+
+    #[test]
+    fn extension_trace_deserializes() {
+        let v = json!({
+            "version": 3,
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "started_at": "2026-07-21T07:59:00Z",
+            "purpose": "demo",
+            "stopped_by": "user_finish",
+            "entry": { "start_url": "https://example.com/editor" },
+            "recorder": { "bsk": "0.1.10", "vom": 1 },
+            "states": [
+                { "id": "s1", "url": "https://example.com/editor", "body": "@vom 1" },
+                { "id": "s2", "url": "https://example.com/p/99", "body": "@vom 1" }
+            ],
+            "steps": [
+                {
+                    "op": "fill",
+                    "id": 1,
+                    "state": "s1",
+                    "result": { "state": "s1" },
+                    "target": { "ref": "e1", "role": "textbox", "name": "标题" },
+                    "value": "hello",
+                    "commit": "blur"
+                },
+                {
+                    "op": "click",
+                    "id": 2,
+                    "state": "s1",
+                    "result": { "state": "s2" },
+                    "target": { "ref": "e2", "role": "button", "name": "发布" }
+                }
+            ]
+        });
+        let trace: TraceV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(trace.version, 3);
+        assert_eq!(trace.states.len(), 2);
+        assert_eq!(trace.steps.len(), 2);
+    }
+}

packages/dsh-plugin-browserskill/README.md

@@ -6,7 +6,7 @@ A [DeepSeek Harness](https://github.com/deepseek-ai/deepseek-harness) (dsh) tool
 [BrowserSkill](https://github.com/Tencent/BrowserSkill) (`bsk`) browser automation to the model.
 
 Each tool maps to one `bsk <cmd> --json` invocation: the plugin spawns the bsk CLI, parses its
-structured JSON output, and returns a canonical typed value. The bsk daemon, browser, and Chrome
+structured JSON output, and returns a canonical typed value. The bsk daemon, browser, and browser
 extension keep owning the actual browser control — this package is a thin, well-typed bridge.
 
 ## Tools
@@ -64,9 +64,10 @@ dsh plugin --profile <name> add @wxg-prc-cpg/browser-skill-dsh-plugin
 dsh --profile <name>
 ```
 
-Prerequisite: the `bsk` CLI must be installed and on `PATH`, and the BrowserSkill Chrome extension
-must be connected — see the [BrowserSkill README](https://github.com/Tencent/BrowserSkill). When bsk
-is missing, tool calls fail with install guidance instead of a bare spawn error.
+Prerequisite: the `bsk` CLI must be installed and on `PATH`, and the BrowserSkill browser extension
+(Chrome or Edge) must be connected — see the
+[BrowserSkill README](https://github.com/Tencent/BrowserSkill). When bsk is missing, tool calls fail
+with install guidance instead of a bare spawn error.
 
 ## Configuration
 
@@ -76,7 +77,7 @@ All fields are optional and validated through the plugin's Schemastery `Config`:
 # cordis.patch.yml override example
 - insert:
     - id: browserskill
-      name: dsh-plugin-browserskill
+      name: "@wxg-prc-cpg/browser-skill-dsh-plugin"
       config:
         bskPath: bsk          # path to the bsk binary (default: resolve from PATH)
         defaultTimeoutMs: 120000
@@ -186,8 +187,8 @@ git tag dsh-plugin-v0.1.0
 git push origin dsh-plugin-v0.1.0
 ```
 
-Or run the workflow from the Actions tab (`workflow_dispatch`). The job reads
-`NPM_TOKEN` from the GitHub Environment of the same name.
+Or run the workflow from the Actions tab (`workflow_dispatch`). The job reads the
+`NPM_TOKEN` secret from the `npm-publish` GitHub Environment.
 
 ## License
 

packages/dsh-plugin-browserskill/cordis.patch.yml

@@ -1,3 +1,5 @@
 - insert:
     - id: browserskill
-      name: dsh-plugin-browserskill
+      # Must be the published package name — the loader imports this specifier.
+      # Quoted because YAML reserves a leading '@' in plain scalars.
+      name: "@wxg-prc-cpg/browser-skill-dsh-plugin"

packages/dsh-plugin-browserskill/package.json

@@ -1,7 +1,7 @@
 {
   "name": "@wxg-prc-cpg/browser-skill-dsh-plugin",
   "description": "DeepSeek Harness tool plugin that exposes BrowserSkill (bsk) browser automation to the model",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "license": "MIT",
   "publishConfig": {
     "access": "public",

packages/dsh-plugin-browserskill/src/observation.ts

@@ -12,7 +12,7 @@
  * events, and never move the registry's current pointer.
  */
 
-import { createHash } from "node:crypto";
+import { createHash, randomUUID } from "node:crypto";
 import { readFile, unlink } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
@@ -78,6 +78,7 @@ const FAILURE_BACKOFF_THRESHOLD = 3;
 const FRAME_RING_SIZE = 2;
 
 export class ObservationService {
+  private readonly scratchNamespace = randomUUID();
   private readonly observations = new Map<string, SessionObservation>();
   private readonly listeners = new Set<(event: ObservationEvent) => void>();
   private readonly captureTimers = new Map<string, unknown>();
@@ -304,9 +305,9 @@ export class ObservationService {
     if (current === undefined || current.dead === true) return;
     if (this.captureInFlight.has(sessionId)) return;
     this.captureInFlight.add(sessionId);
-    // One fixed scratch path per session (overwritten each frame) and always
-    // unlinked after the bytes are read — /tmp must not grow without bound.
-    const outPath = join(tmpdir(), `bsk-obs-${sessionId}.png`);
+    // Stable within this service, isolated from captures owned by other instances.
+    const sessionKey = createHash("sha256").update(sessionId).digest("hex").slice(0, 16);
+    const outPath = join(tmpdir(), `bsk-obs-${this.scratchNamespace}-${sessionKey}.png`);
     let writtenPath = outPath;
     try {
       const result = await this.deps.queue.run(sessionId, () =>

packages/dsh-plugin-browserskill/tests/observation.test.ts

@@ -5,7 +5,7 @@
 import { existsSync, mkdtempSync, writeFileSync } from "node:fs";
 import type { IncomingMessage, ServerResponse } from "node:http";
 import { tmpdir } from "node:os";
-import { join } from "node:path";
+import { basename, dirname } from "node:path";
 import { describe, expect, it } from "vitest";
 import {
   actionForLabel,
@@ -145,7 +145,7 @@ function own(registry: SessionRegistry, sessionId: string): void {
 }
 
 /** Poll until the condition holds (capture completion is real async I/O). */
-async function waitFor(cond: () => boolean, timeoutMs = 2000): Promise<void> {
+async function waitFor(cond: () => boolean, timeoutMs = 10_000): Promise<void> {
   const start = Date.now();
   while (!cond()) {
     if (Date.now() - start > timeoutMs) throw new Error("waitFor timeout");
@@ -525,22 +525,6 @@ describe("availability and dead sessions", () => {
   });
 });
 
-describe("thumbnail read-back", () => {
-  it("serves captured frames through readThumbnail and 404s unknown ids", async () => {
-    const scheduler = fakeScheduler();
-    const runner = fakeRunner();
-    const { service } = setup({ runner, scheduler });
-    service.addSession("s1");
-    scheduler.runNext();
-    await waitFor(() => service.getState()[0]?.thumbnailAttachmentId !== undefined);
-    const frame = await service.readThumbnail("obs-s1-1");
-    expect(frame?.mediaType).toBe("image/png");
-    expect([...(frame?.data ?? [])]).toEqual([0x89, 0x50, 0x4e, 0x47]);
-    expect(await service.readThumbnail("nope")).toBeUndefined();
-    service.dispose();
-  });
-});
-
 describe("actionForLabel", () => {
   it("maps tool labels onto observation verbs", () => {
     expect(actionForLabel("navigate")).toBe("navigating");
@@ -564,8 +548,12 @@ describe("scratch files and thumbnail references", () => {
     );
     const firstOut = runner.calls.filter((c) => c.args[0] === "screenshot").at(-1)?.args;
     const pathOf = (args: string[]) => args[args.indexOf("--out") + 1];
-    expect(pathOf(firstOut ?? [])).toBe(join(tmpdir(), "bsk-obs-s1.png"));
-    expect(existsSync(pathOf(firstOut ?? []))).toBe(false);
+    const firstPath = pathOf(firstOut ?? []);
+    expect(dirname(firstPath)).toBe(tmpdir());
+    expect(basename(firstPath)).toMatch(
+      /^bsk-obs-[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}-[0-9a-f]{16}\.png$/,
+    );
+    expect(existsSync(firstPath)).toBe(false);
     // second frame: same path, deleted again
     service.endAction("s1");
     scheduler.runNext();
@@ -575,11 +563,33 @@ describe("scratch files and thumbnail references", () => {
         scheduler.pending().length === 1,
     );
     const secondOut = runner.calls.filter((c) => c.args[0] === "screenshot").at(-1)?.args;
-    expect(pathOf(secondOut ?? [])).toBe(join(tmpdir(), "bsk-obs-s1.png"));
-    await waitFor(() => !existsSync(pathOf(secondOut ?? [])));
+    const secondPath = pathOf(secondOut ?? []);
+    expect(secondPath).toBe(firstPath);
+    await waitFor(() => !existsSync(secondPath));
     service.dispose();
   });
 
+  it("isolates scratch paths between service instances", async () => {
+    const first = setup({ scheduler: fakeScheduler(), runner: fakeRunner() });
+    const second = setup({ scheduler: fakeScheduler(), runner: fakeRunner() });
+    first.service.addSession("s1");
+    second.service.addSession("s1");
+    first.scheduler.runNext();
+    second.scheduler.runNext();
+    await waitFor(
+      () =>
+        first.service.getState()[0]?.thumbnailAttachmentId !== undefined &&
+        second.service.getState()[0]?.thumbnailAttachmentId !== undefined,
+    );
+    const pathOf = (runner: FakeRunner) => {
+      const args = runner.calls.find((call) => call.args[0] === "screenshot")?.args ?? [];
+      return args[args.indexOf("--out") + 1];
+    };
+    expect(pathOf(first.runner)).not.toBe(pathOf(second.runner));
+    first.service.dispose();
+    second.service.dispose();
+  });
+
   it("keeps the last two distinct frames and evicts the third", async () => {
     let n = 0;
     const runner = fakeRunner({

packages/dsh-plugin-browserskill/tsdown.config.ts

@@ -2,6 +2,7 @@ import { readFile } from "node:fs/promises";
 import { basename, dirname, resolve as resolvePath } from "node:path";
 import { transform } from "lightningcss";
 import { defineConfig, type UserConfig } from "tsdown";
+import pkg from "./package.json" with { type: "json" };
 
 /**
  * Two build faces of the dual-face package:
@@ -33,7 +34,10 @@ const VENDORED_LIBRARY = /^@deepseek-ai\/(cosmokit|schemastery)(\/|$)/;
 
 const CSS_VIRTUAL_PREFIX = "\0bsk-css:";
 const CSS_VIRTUAL_SUFFIX = ".mjs";
-const CLIENT_ID = "dsh-plugin-browserskill";
+// The web shell resolves client bundles from its module table by package name
+// (dsh's own bundles register the same way), so this must never drift from
+// package.json.
+const CLIENT_ID = pkg.name;
 
 const client: UserConfig = {
   name: `${CLIENT_ID}/client`,