Fix comment formatting in useDaemonPort function

修复注释不准确 Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
Fix regex for validating daemon port input
2026-09-10 13:01:23 +08:00 · 2026-09-03 19:58:49 +08:00 · 2026-09-03 19:57:12 +08:00 · 2026-09-02 19:18:03 +08:00 · 2026-09-02 18:56:08 +08:00 · 2026-09-02 16:47:19 +08:00
255 changed files with 30969 additions and 4133 deletions
@@ -325,3 +325,180 @@ jobs:

          echo "Chrome Web Store submission created successfully:"
          jq '{itemId, state, warningInfo}' "$PUBLISH_RESPONSE"
+
+  publish-edge-addons:
+    needs: [resolve, build-extension]
+    runs-on: ubuntu-latest
+    environment: edge-addons
+    permissions:
+      contents: read
+    steps:
+      - name: Download build artifact
+        uses: actions/download-artifact@v8
+        with:
+          name: extension-zip
+          path: dist
+
+      - name: Validate Microsoft Edge Add-ons configuration
+        shell: bash
+        env:
+          API_KEY: ${{ secrets.EDGE_ADDONS_API_KEY }}
+          CLIENT_ID: ${{ vars.EDGE_ADDONS_CLIENT_ID }}
+          PRODUCT_ID: ${{ vars.EDGE_ADDONS_PRODUCT_ID }}
+        run: |
+          set -euo pipefail
+          if [ -z "$API_KEY" ]; then
+            echo "::error::Environment secret EDGE_ADDONS_API_KEY is not configured"
+            exit 1
+          fi
+          if [ -z "$CLIENT_ID" ]; then
+            echo "::error::Environment variable EDGE_ADDONS_CLIENT_ID is not configured"
+            exit 1
+          fi
+          if [ -z "$PRODUCT_ID" ]; then
+            echo "::error::Environment variable EDGE_ADDONS_PRODUCT_ID is not configured"
+            exit 1
+          fi
+          if ! [[ "$PRODUCT_ID" =~ ^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$ ]]; then
+            echo "::error::EDGE_ADDONS_PRODUCT_ID must be the Partner Center product GUID, not the public Edge Add-ons extension ID"
+            exit 1
+          fi
+
+          ARCHIVE="$(find dist -maxdepth 1 -name '*.zip' -type f -print -quit)"
+          if [ -z "$ARCHIVE" ]; then
+            echo "::error::No extension zip found in the downloaded artifact"
+            exit 1
+          fi
+          echo "ARCHIVE=$ARCHIVE" >> "$GITHUB_ENV"
+
+      - name: Upload and publish Microsoft Edge Add-ons extension
+        shell: bash
+        env:
+          API_KEY: ${{ secrets.EDGE_ADDONS_API_KEY }}
+          CLIENT_ID: ${{ vars.EDGE_ADDONS_CLIENT_ID }}
+          PRODUCT_ID: ${{ vars.EDGE_ADDONS_PRODUCT_ID }}
+          RELEASE_VERSION: ${{ needs.resolve.outputs.version }}
+        run: |
+          set -euo pipefail
+          API_ROOT="https://api.addons.microsoftedge.microsoft.com/v1"
+          UPLOAD_HEADERS="$RUNNER_TEMP/edge-upload-headers.txt"
+          UPLOAD_RESPONSE="$RUNNER_TEMP/edge-upload-response.json"
+          STATUS_RESPONSE="$RUNNER_TEMP/edge-status-response.json"
+          PUBLISH_HEADERS="$RUNNER_TEMP/edge-publish-headers.txt"
+          PUBLISH_RESPONSE="$RUNNER_TEMP/edge-publish-response.json"
+
+          operation_id_from_headers() {
+            local headers="$1"
+            local location
+            location="$(awk '
+              tolower($1) == "location:" {
+                sub(/\r$/, "")
+                sub(/^[^:]*:[[:space:]]*/, "")
+                print
+                exit
+              }
+            ' "$headers")"
+            location="${location%%\?*}"
+            printf '%s' "${location##*/}"
+          }
+
+          poll_operation() {
+            local operation_name="$1"
+            local status_url="$2"
+            local status="InProgress"
+            local http_status
+
+            for attempt in $(seq 1 30); do
+              sleep 5
+              http_status="$(curl --silent --show-error \
+                --output "$STATUS_RESPONSE" \
+                --write-out '%{http_code}' \
+                --header "Authorization: ApiKey $API_KEY" \
+                --header "X-ClientID: $CLIENT_ID" \
+                "$status_url")"
+              if [ "$http_status" -lt 200 ] || [ "$http_status" -ge 300 ]; then
+                echo "::error::Microsoft Edge Add-ons $operation_name status check failed with HTTP $http_status"
+                jq . "$STATUS_RESPONSE" || cat "$STATUS_RESPONSE"
+                exit 1
+              fi
+
+              status="$(jq -r '.status // empty' "$STATUS_RESPONSE")"
+              echo "$operation_name status check $attempt/30: $status"
+              case "$status" in
+                Succeeded)
+                  return 0
+                  ;;
+                InProgress)
+                  ;;
+                Failed)
+                  echo "::error::Microsoft Edge Add-ons $operation_name failed"
+                  jq . "$STATUS_RESPONSE"
+                  exit 1
+                  ;;
+                *)
+                  echo "::error::Microsoft Edge Add-ons returned an unknown $operation_name status: $status"
+                  jq . "$STATUS_RESPONSE"
+                  exit 1
+                  ;;
+              esac
+            done
+
+            echo "::error::Microsoft Edge Add-ons $operation_name did not complete after 30 checks"
+            jq . "$STATUS_RESPONSE"
+            exit 1
+          }
+
+          HTTP_STATUS="$(curl --silent --show-error \
+            --output "$UPLOAD_RESPONSE" \
+            --dump-header "$UPLOAD_HEADERS" \
+            --write-out '%{http_code}' \
+            --request POST \
+            --header "Authorization: ApiKey $API_KEY" \
+            --header "X-ClientID: $CLIENT_ID" \
+            --header "Content-Type: application/zip" \
+            --data-binary "@$ARCHIVE" \
+            "$API_ROOT/products/$PRODUCT_ID/submissions/draft/package")"
+          if [ "$HTTP_STATUS" != "202" ]; then
+            echo "::error::Microsoft Edge Add-ons upload failed with HTTP $HTTP_STATUS"
+            jq . "$UPLOAD_RESPONSE" || cat "$UPLOAD_RESPONSE"
+            exit 1
+          fi
+
+          UPLOAD_OPERATION_ID="$(operation_id_from_headers "$UPLOAD_HEADERS")"
+          if [ -z "$UPLOAD_OPERATION_ID" ]; then
+            echo "::error::Microsoft Edge Add-ons upload response has no Location operation ID"
+            cat "$UPLOAD_HEADERS"
+            exit 1
+          fi
+          poll_operation \
+            "package upload" \
+            "$API_ROOT/products/$PRODUCT_ID/submissions/draft/package/operations/$UPLOAD_OPERATION_ID"
+
+          HTTP_STATUS="$(curl --silent --show-error \
+            --output "$PUBLISH_RESPONSE" \
+            --dump-header "$PUBLISH_HEADERS" \
+            --write-out '%{http_code}' \
+            --request POST \
+            --header "Authorization: ApiKey $API_KEY" \
+            --header "X-ClientID: $CLIENT_ID" \
+            --header "Content-Type: application/json" \
+            --data "{\"notes\":\"Automated BrowserSkill extension v${RELEASE_VERSION} release from GitHub Actions.\"}" \
+            "$API_ROOT/products/$PRODUCT_ID/submissions")"
+          if [ "$HTTP_STATUS" != "202" ]; then
+            echo "::error::Microsoft Edge Add-ons publish failed with HTTP $HTTP_STATUS"
+            jq . "$PUBLISH_RESPONSE" || cat "$PUBLISH_RESPONSE"
+            exit 1
+          fi
+
+          PUBLISH_OPERATION_ID="$(operation_id_from_headers "$PUBLISH_HEADERS")"
+          if [ -z "$PUBLISH_OPERATION_ID" ]; then
+            echo "::error::Microsoft Edge Add-ons publish response has no Location operation ID"
+            cat "$PUBLISH_HEADERS"
+            exit 1
+          fi
+          poll_operation \
+            "submission" \
+            "$API_ROOT/products/$PRODUCT_ID/submissions/operations/$PUBLISH_OPERATION_ID"
+
+          echo "Microsoft Edge Add-ons submission created successfully:"
+          jq '{status, message, errorCode, errors}' "$STATUS_RESPONSE"
@@ -7,10 +7,18 @@ dist/
 .output/
 .wxt/
 .web-extension-id
+.pnpm-store/
+
+# Git worktrees
+.worktrees/

 # Logs
 *.log

+# Local browser evaluation artifacts
+evals/browser/results/
+evals/browser/agents.local.json
+
 # macOS
 .DS_Store

@@ -134,9 +134,10 @@ dependencies = [

 [[package]]
 name = "bsk"
-version = "0.1.10"
+version = "0.1.11"
 dependencies = [
 "anyhow",
+ "base64",
 "bsk-protocol",
 "clap",
 "console",
@@ -168,7 +169,7 @@ dependencies = [

 [[package]]
 name = "bsk-protocol"
-version = "0.1.10"
+version = "0.1.11"
 dependencies = [
 "schemars",
 "semver",
@@ -7,7 +7,7 @@ members = [
 default-members = ["crates/bsk-cli"]

 [workspace.package]
-version = "0.1.10"
+version = "0.1.11"
 edition = "2024"
 rust-version = "1.85"
 license = "MIT"
@@ -36,6 +36,7 @@ flate2 = "1.1.9"
 tar = "0.4.46"
 zip = { version = "7.2.0", default-features = false, features = ["deflate"] }
 sha2 = "0.11.0"
+base64 = "0.22"
 tempfile = "3"
 nix = { version = "0.29", features = ["signal", "process"] }
 rand = "0.8"
@@ -208,6 +208,7 @@ The repository is a Cargo + pnpm workspace:
 - `apps/extension` — browser extension
 - `packages/ui` and `packages/i18n` — shared extension UI support
 - `packages/dsh-plugin-browserskill` — DeepSeek Harness plugin (`@wxg-prc-cpg/browser-skill-dsh-plugin`)
+- [`evals/browser`](evals/browser/README.md) — deterministic local pages and agent-neutral browser capability evaluation

 ## License

@@ -178,6 +178,7 @@ Agent 不直接与浏览器通信。它通过 `bsk` CLI 下发浏览器任务；
 - `apps/extension` — 浏览器扩展
 - `packages/ui` 和 `packages/i18n` — 扩展 UI 共享支持
 - `packages/dsh-plugin-browserskill` — DeepSeek Harness 插件（`@wxg-prc-cpg/browser-skill-dsh-plugin`）
+- [`evals/browser`](evals/browser/README.zh-CN.md) — 确定性本地页面与 Agent 无关的浏览器能力测试台

 ## 许可证

@@ -1,6 +1,6 @@
 # BrowserSkill — Privacy Policy

-**Last updated:** May 25, 2026
+**Last updated:** August 20, 2026

 This Privacy Policy describes how the **BrowserSkill** browser extension (the "Extension") handles information when you install and use it. BrowserSkill is published as part of the open-source [BrowserSkill](https://github.com/Tencent/BrowserSkill) project. The source code is publicly auditable.

@@ -14,7 +14,7 @@ BrowserSkill is a local automation bridge that lets AI coding agents (such as Cu

 ## 2. Single Purpose

-The Extension's single purpose is to expose browser automation primitives (navigation, DOM observation, screenshots, clicks, form filling, tab management) to a locally running BrowserSkill daemon over a WebSocket connection on `127.0.0.1`, so that an AI agent invoked by the user can interact with web pages on the user's behalf.
+The Extension's single purpose is to expose browser automation primitives (navigation, DOM observation, screenshots, clicks, form filling, task-scoped file transfer, and tab management) to a locally running BrowserSkill daemon over a WebSocket connection on `127.0.0.1`, so that an AI agent invoked by the user can interact with web pages on the user's behalf.

 ## 3. Data the Extension Accesses

@@ -26,6 +26,7 @@ Depending on the commands the user (via their AI agent) sends to the local daemo
 | **User input simulated by the agent** | Mouse clicks, keystrokes, and form values that the AI agent dispatches through the Chrome DevTools Protocol (CDP). | Required to perform automation actions the user has asked the agent to do. |
 | **Tab and window metadata** | Tab IDs, URLs, titles, window IDs of the Agent Window and any tabs the user explicitly authorizes. | Required to target automation commands at the correct tab/window. |
 | **Local extension storage** | A randomly generated 8-character instance ID and an optional user-supplied label. | Used so the local daemon can recognize this browser instance across reconnects. No personal data is stored. |
+| **File transfers requested by the agent** | Local files explicitly supplied to `bsk upload`, and the file created by a single `bsk download` action. | Required to attach a task file to a web page or return a browser-generated download to the invoking local agent. |
 | **OS notifications** | Permission to display a system notification when the agent requests to "borrow" one of the user's existing tabs. | Required to obtain explicit, per-tab user consent before the agent touches any pre-existing tab. |

 ## 4. Data the Extension Does **Not** Collect
@@ -34,7 +35,7 @@ BrowserSkill does **not**:

 - Send any data to remote servers, the Extension's authors, or any third party.
 - Call any LLM, AI, or cloud API. The Extension contains no API keys, model identifiers, or remote endpoints.
- Read or transmit cookies, browsing history, bookmarks, downloads, saved passwords, or autofill data.
+- Read or transmit cookies, browsing history, bookmarks, saved passwords, or autofill data. It observes only the download initiated by an active `bsk download` call, not download history generally.
 - Use webcam, microphone, geolocation, or any device sensor.
 - Include analytics, telemetry, crash reporting, advertising SDKs, or fingerprinting code.
 - Track users across websites or across sessions.
@@ -50,17 +51,19 @@ The Extension requests the following Chrome permissions. Each is used solely for
 - **`alarms`** — Periodically wake the service worker to keep the local WebSocket connection alive.
 - **`idle`** — Detect when the device returns from idle/locked so the Extension can promptly re-establish the local WebSocket connection after the machine wakes. No idle data is stored or transmitted.
 - **`notifications`** — Show a system notification to obtain user approval before the agent borrows a user-owned tab.
+- **`downloads`** — Correlate and route the one browser download initiated by an active `bsk download` command. If that claimed transaction fails, BrowserSkill cancels an in-progress file or removes its completed temporary browser file. It is not used to enumerate download history or alter unclaimed downloads.
 - **`storage`** — Persist a random instance ID and optional label in `chrome.storage.local`.
 - **Host permission `<all_urls>`** — Inject a small status overlay (showing "Agent Active") on pages controlled by the agent, and enable automation across whatever sites the user directs the agent to. The Extension does **not** read or transmit page content from sites the agent is not actively driving.

 ## 6. Where Data Goes

-All Extension activity stays on the user's local device. The only network traffic the Extension generates is a WebSocket connection to `ws://127.0.0.1:52800` (loopback only). What the AI agent connected to that local daemon does with the data afterwards (for example, sending a screenshot to an LLM provider) is governed by the privacy policy of that agent or LLM provider, **not** by this policy. BrowserSkill is not a party to those communications.
+All Extension activity stays on the user's local device. The only network traffic the Extension generates is a WebSocket connection to the local bsk daemon on `127.0.0.1` (loopback only; default port **52800**, configurable in the extension popup). What the AI agent connected to that local daemon does with the data afterwards (for example, sending a screenshot to an LLM provider) is governed by the privacy policy of that agent or LLM provider, **not** by this policy. BrowserSkill is not a party to those communications.

 ## 7. Data Retention

 - The instance ID and optional label persist in `chrome.storage.local` until the user uninstalls the Extension or clears extension storage.
 - Page content, screenshots, DOM snapshots, and other observed data are returned to the local daemon in response to commands and are **not retained by the Extension**. They live only as long as the agent's tool call.
+- Upload and download bytes are staged by the local daemon in a private, session-scoped directory. Download staging is removed after it is copied to the requested destination. Upload staging is retained until the session ends so a later form submission can still read the attached file. Remaining staging is removed when the session ends or disconnects, or when the daemon next starts after a crash.

 ## 8. User Control

@@ -77,7 +80,7 @@ The Extension is a developer tool and is not directed at children under 13. It d

 ## 10. Security

-Because the Extension communicates only with `127.0.0.1`, no data is exposed to the network. Users should still avoid running BrowserSkill in untrusted environments, since any local process able to bind to `127.0.0.1:52800` could send commands to the Extension. Run BrowserSkill only on machines you control.
+Because the Extension communicates only with `127.0.0.1`, no data is exposed to the network. Users should still avoid running BrowserSkill in untrusted environments, since any local process able to bind to the configured loopback port could send commands to the Extension. Run BrowserSkill only on machines you control.

 ## 11. Open Source and Auditability

@@ -54,7 +54,7 @@ BrowserSkill **不会**：

 ## 6. 数据流向

-本扩展的所有活动都停留在用户本地设备上。本扩展产生的唯一网络流量是与 `ws://127.0.0.1:52800`（仅回环地址）的 WebSocket 连接。连接到该本地守护进程的 AI 助手在拿到数据之后如何处理（例如将截图发送给某个 LLM 服务），由该助手或 LLM 提供商自身的隐私政策约束，**不在本政策范围内**。BrowserSkill 不参与那些通信。
+本扩展的所有活动都停留在用户本地设备上。本扩展产生的唯一网络流量是与本地 bsk 守护进程在 `127.0.0.1`（仅回环地址；默认端口 **52800**，可在扩展弹窗中配置）上的 WebSocket 连接。连接到该本地守护进程的 AI 助手在拿到数据之后如何处理（例如将截图发送给某个 LLM 服务），由该助手或 LLM 提供商自身的隐私政策约束，**不在本政策范围内**。BrowserSkill 不参与那些通信。

 ## 7. 数据保留

@@ -76,7 +76,7 @@ BrowserSkill **不会**：

 ## 10. 安全性

-由于本扩展仅与 `127.0.0.1` 通信，因此不会向网络暴露任何数据。但用户仍应避免在不可信的环境中运行 BrowserSkill —— 任何能够绑定到 `127.0.0.1:52800` 的本地进程理论上都可以向本扩展发送指令。请仅在您本人控制的机器上运行 BrowserSkill。
+由于本扩展仅与 `127.0.0.1` 通信，因此不会向网络暴露任何数据。但用户仍应避免在不可信的环境中运行 BrowserSkill —— 任何能够绑定到所配置回环端口的本地进程理论上都可以向本扩展发送指令。请仅在您本人控制的机器上运行 BrowserSkill。

 ## 11. 开源与可审计性

@@ -1,6 +1,6 @@
 {
  "name": "@browser-skill/extension",
-  "version": "0.1.6",
+  "version": "0.1.7",
  "private": true,
  "type": "module",
  "scripts": {
@@ -23,7 +23,7 @@ describe("BorrowConfirmationOverlay", () => {
            id: "req-1",
            isActiveTab: true,
            tabTitle: "Example",
-            timeoutMs: 5000,
+            timeoutMs: 60_000,
            onAllow,
            onDeny,
          },
@@ -32,7 +32,7 @@ describe("BorrowConfirmationOverlay", () => {
    );

    expect(screen.getByText("允许借用标签页？")).toBeTruthy();
-    for (let i = 0; i < 5; i++) {
+    for (let i = 0; i < 60; i++) {
      await act(async () => {
        await vi.advanceTimersByTimeAsync(1000);
      });
@@ -66,7 +66,7 @@ describe("BorrowConfirmationOverlay", () => {
            id: "req-fallback",
            isActiveTab: true,
            tabTitle: "Example",
-            timeoutMs: 5000,
+            timeoutMs: 60_000,
            onAllow,
            onDeny,
          },
@@ -74,7 +74,7 @@ describe("BorrowConfirmationOverlay", () => {
      />,
    );

-    for (let i = 0; i < 5; i++) {
+    for (let i = 0; i < 60; i++) {
      await act(async () => {
        await vi.advanceTimersByTimeAsync(1000);
      });
@@ -1,10 +1,12 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
-import { RECORD_STOP, type RecordStepPayload } from "@/lib/record-bridge";
-import { handleRecordContentMessage, startRecordCapture } from "../record-capture";
+import type { RecordStepPayload } from "@/lib/record-bridge";
+import { startRecordCapture } from "../record-capture";

 vi.stubGlobal("chrome", {
  runtime: {
-    sendMessage: vi.fn(() => Promise.resolve()),
+    sendMessage: vi.fn((message: { sequence?: number }) =>
+      Promise.resolve({ ok: true, sequence: message.sequence }),
+    ),
  },
 });

@@ -46,58 +48,6 @@ function click(el: Element): void {
  el.dispatchEvent(new MouseEvent("click", { bubbles: true, button: 0, detail: 1 }));
 }

-describe("handleRecordContentMessage stop/cancel", () => {
-  it("ignores STOP when no recording is active", () => {
-    const dispose = vi.fn();
-    const onStop = vi.fn();
-    const setActiveRequestId = vi.fn();
-    const setCapture = vi.fn();
-    const sendResponse = vi.fn();
-
-    const needsAsync = handleRecordContentMessage(
-      { type: RECORD_STOP, requestId: "rec-stale" },
-      {
-        activeRequestId: null,
-        capture: { dispose },
-        setActiveRequestId,
-        setCapture,
-        onStart: vi.fn(),
-        onStop,
-      },
-      sendResponse,
-    );
-
-    expect(needsAsync).toBe(false);
-    expect(dispose).not.toHaveBeenCalled();
-    expect(onStop).not.toHaveBeenCalled();
-    expect(setActiveRequestId).not.toHaveBeenCalled();
-    expect(setCapture).not.toHaveBeenCalled();
-    expect(sendResponse).not.toHaveBeenCalled();
-  });
-
-  it("ignores STOP for a mismatched requestId", () => {
-    const dispose = vi.fn();
-    const onStop = vi.fn();
-
-    const needsAsync = handleRecordContentMessage(
-      { type: RECORD_STOP, requestId: "rec-other" },
-      {
-        activeRequestId: "rec-1",
-        capture: { dispose },
-        setActiveRequestId: vi.fn(),
-        setCapture: vi.fn(),
-        onStart: vi.fn(),
-        onStop,
-      },
-      vi.fn(),
-    );
-
-    expect(needsAsync).toBe(false);
-    expect(dispose).not.toHaveBeenCalled();
-    expect(onStop).not.toHaveBeenCalled();
-  });
-});
-
 describe("record-capture semantic", () => {
  let steps: RecordStepPayload[];

@@ -174,6 +124,19 @@ describe("record-capture semantic", () => {
    ]);
  });

+  it("does not emit page navigation from a child Document capture", () => {
+    const originalUrl = location.href;
+    const capture = startRecordCapture("rec-child", (step) => steps.push(step), {
+      captureNavigation: false,
+    });
+
+    history.pushState({}, "", "#inside-frame");
+    expect(steps).toEqual([]);
+
+    capture.dispose();
+    history.replaceState({}, "", originalUrl);
+  });
+
  it("does not record clicks on anonymous layout divs", () => {
    document.body.innerHTML = `
      <div id="chrome">page chrome</div>
@@ -228,6 +191,7 @@ describe("record-capture semantic", () => {
    expect(steps[0]).toMatchObject({
      op: "hover",
      target: { role: "button", name: "Open user navigation menu" },
+      geometry: { tag: "button", rect: { x: 900, y: 8, w: 32, h: 32 } },
    });
    expect(steps[1]).toMatchObject({
      op: "click",
@@ -0,0 +1,102 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { RecordFramePortMessage } from "@/lib/recording/frame-bridge";
+import { RECORD_FRAME_START } from "@/lib/recording/frame-bridge";
+import { RECORD_DOCUMENT_ATTRIBUTE } from "@/shared/recording-document-identity";
+import { RecordFrameAgent } from "../recording/frame-agent";
+
+class PortListeners<T extends (...args: never[]) => unknown> {
+  readonly values = new Set<T>();
+  addListener = (listener: T) => this.values.add(listener);
+  removeListener = (listener: T) => this.values.delete(listener);
+}
+
+function portHarness() {
+  const onMessage = new PortListeners<(message: unknown) => void>();
+  const onDisconnect = new PortListeners<() => void>();
+  const outbound: RecordFramePortMessage[] = [];
+  const port = {
+    name: "bsk-record-frame",
+    onMessage,
+    onDisconnect,
+    postMessage(message: RecordFramePortMessage) {
+      outbound.push(message);
+      if (message.type === "ready") {
+        queueMicrotask(() => {
+          for (const listener of onMessage.values) {
+            listener({
+              type: "ready_ack",
+              requestId: message.requestId,
+              producerId: message.producerId,
+            });
+          }
+        });
+      }
+    },
+    disconnect: vi.fn(),
+  } as unknown as chrome.runtime.Port;
+  return {
+    port,
+    outbound,
+    receive(message: RecordFramePortMessage) {
+      for (const listener of onMessage.values) listener(message);
+    },
+  };
+}
+
+describe("RecordFrameAgent", () => {
+  afterEach(() => {
+    document.documentElement.removeAttribute(RECORD_DOCUMENT_ATTRIBUTE);
+    document.body.replaceChildren();
+  });
+
+  it("keeps a failed stop retryable and flushes the final dirty fill", async () => {
+    const harness = portHarness();
+    const sendMessage = vi
+      .fn<(message: { sequence: number }) => Promise<unknown>>()
+      .mockRejectedValueOnce(new Error("offline"))
+      .mockRejectedValueOnce(new Error("still offline"))
+      .mockImplementation(async (message) => ({ ok: true, sequence: message.sequence }));
+    vi.stubGlobal("chrome", {
+      runtime: {
+        connect: vi.fn(() => harness.port),
+        sendMessage,
+      },
+    });
+    document.body.innerHTML = `<label for="draft">Draft</label><input id="draft" />`;
+    const agent = new RecordFrameAgent();
+
+    await expect(
+      agent.start({ type: RECORD_FRAME_START, requestId: "rec-1", startedAtMs: 10 }),
+    ).resolves.toEqual({ ok: true });
+    expect(document.documentElement.hasAttribute(RECORD_DOCUMENT_ATTRIBUTE)).toBe(true);
+
+    const input = document.querySelector("input")!;
+    input.dispatchEvent(new FocusEvent("focusin", { bubbles: true }));
+    input.value = "final value";
+    input.dispatchEvent(new Event("input", { bubbles: true }));
+
+    harness.receive({ type: "stop", requestId: "rec-1", commandId: "stop-1" });
+    await vi.waitFor(() =>
+      expect(harness.outbound).toContainEqual({
+        type: "stopped",
+        requestId: "rec-1",
+        commandId: "stop-1",
+        ok: false,
+        error: "failed to deliver one or more recorded steps",
+      }),
+    );
+    expect(document.documentElement.hasAttribute(RECORD_DOCUMENT_ATTRIBUTE)).toBe(true);
+
+    harness.receive({ type: "stop", requestId: "rec-1", commandId: "stop-2" });
+    await vi.waitFor(() =>
+      expect(harness.outbound).toContainEqual({
+        type: "stopped",
+        requestId: "rec-1",
+        commandId: "stop-2",
+        ok: true,
+      }),
+    );
+    expect(sendMessage).toHaveBeenCalledTimes(3);
+    expect(document.documentElement.hasAttribute(RECORD_DOCUMENT_ATTRIBUTE)).toBe(false);
+  });
+});
@@ -0,0 +1,36 @@
+import { describe, expect, it, vi } from "vitest";
+import type { RecordStepMessage } from "@/lib/record-bridge";
+import { RecordStepDelivery } from "../record-step-delivery";
+
+describe("RecordStepDelivery", () => {
+  it("retries from the first unacknowledged sequence before sending later steps", async () => {
+    const sent: RecordStepMessage[] = [];
+    const send = vi.fn(async (message: RecordStepMessage) => {
+      sent.push(message);
+      if (sent.length === 1) throw new Error("service worker unavailable");
+      return { ok: true, sequence: message.sequence };
+    });
+    const delivery = new RecordStepDelivery("rec-ordered", send, "document-1");
+
+    delivery.enqueue({ op: "click", target: { tag: "button", name: "First" } });
+    delivery.enqueue({ op: "click", target: { tag: "button", name: "Second" } });
+
+    await expect(delivery.flush()).resolves.toBe(true);
+    expect(sent.map((message) => message.sequence)).toEqual([1, 1, 2]);
+    expect(sent.map((message) => message.step.target?.name)).toEqual(["First", "First", "Second"]);
+  });
+
+  it("keeps unacknowledged steps pending for a later flush", async () => {
+    const send = vi
+      .fn<(message: RecordStepMessage) => Promise<unknown>>()
+      .mockRejectedValueOnce(new Error("offline"))
+      .mockRejectedValueOnce(new Error("still offline"))
+      .mockImplementation(async (message) => ({ ok: true, sequence: message.sequence }));
+    const delivery = new RecordStepDelivery("rec-retry", send, "document-1");
+    delivery.enqueue({ op: "click", target: { tag: "button", name: "Save" } });
+
+    await expect(delivery.flush()).resolves.toBe(false);
+    await expect(delivery.flush()).resolves.toBe(true);
+    expect(send).toHaveBeenCalledTimes(3);
+  });
+});
@@ -1,9 +1,9 @@
 import {
+  type CaptureTargetDescriptor,
  describeEventTarget,
  describeTarget,
  resolveClickableElement,
  resolveHoverElement,
-  type TargetDescriptor,
 } from "@/lib/describe-target";
 import {
  evaluateHoverTrigger,
@@ -12,22 +12,8 @@ import {
  hasDirectHoverInteractiveSignal,
  hasStrongHoverExpansionSignal,
 } from "@/lib/hover-trigger-policy";
-import {
-  isRecordCancelMessage,
-  isRecordStartMessage,
-  isRecordStopMessage,
-  RECORD_CANCEL,
-  RECORD_START,
-  RECORD_STEP,
-  RECORD_STOP,
-  type RecordCancelMessage,
-  type RecordStartAck,
-  type RecordStartMessage,
-  type RecordStepPayload,
-  type RecordStopAck,
-  type RecordStopMessage,
-} from "@/lib/record-bridge";
-import { shouldRecordPress } from "@/lib/trace-reducer";
+import type { RecordStepPayload } from "@/lib/record-bridge";
+import { shouldRecordPress } from "@/lib/recording/draft-policy";
 import {
  closestHoverSurfaceCandidate,
  collectHoverSurfaceStates,
@@ -37,42 +23,21 @@ import {
  isLikelyHoverSurfaceOwner,
 } from "./record-hover-surface";

-const pendingStepSends = new Map<string, Set<Promise<boolean>>>();
-const failedStepDeliveries = new Set<string>();
-const knownRecordRequests = new Set<string>();
-
-function sendRecordStep(requestId: string, step: RecordStepPayload): void {
-  const payload = { type: RECORD_STEP, requestId, step };
-  const pending = Promise.resolve(chrome.runtime.sendMessage(payload)).then(
-    () => true,
-    () => {
-      failedStepDeliveries.add(requestId);
-      return false;
-    },
-  );
-  const sends = pendingStepSends.get(requestId) ?? new Set<Promise<boolean>>();
-  sends.add(pending);
-  pendingStepSends.set(requestId, sends);
-  void pending.then(() => {
-    sends.delete(pending);
-    if (sends.size === 0) pendingStepSends.delete(requestId);
-  });
-}
-
 export interface RecordCaptureController {
  dispose(): void;
 }

 interface FillSession {
  element: FillableElement;
-  target: TargetDescriptor;
+  target: CaptureTargetDescriptor;
  baselineValue: string;
  lastValue: string;
+  pendingCommit?: "enter" | "suggestion" | "blur";
 }

 interface HoverCandidate {
  element: Element;
-  target: TargetDescriptor;
+  target: CaptureTargetDescriptor;
  recordedAt: number;
  score: number;
  eligible: boolean;
@@ -157,6 +122,24 @@ function nearbyFillableFromSearchChrome(target: Element): FillableElement | null
  return null;
 }

+function captureGeometry(el: Element): RecordStepPayload["geometry"] {
+  const rect = el.getBoundingClientRect();
+  return {
+    rect: { x: rect.x, y: rect.y, w: rect.width, h: rect.height },
+    tag: el.tagName.toLowerCase(),
+  };
+}
+
+function geometryForEventTarget(
+  target: EventTarget | null,
+): RecordStepPayload["geometry"] | undefined {
+  if (!(target instanceof Element)) return undefined;
+  const clickable = target.closest(
+    'a,button,input,select,textarea,[role="button"],[role="link"],[role="menuitem"],[contenteditable="true"]',
+  );
+  return captureGeometry(clickable ?? target);
+}
+
 function fillableValue(el: FillableElement): string {
  if (el instanceof HTMLInputElement || el instanceof HTMLTextAreaElement) {
    return el.value;
@@ -232,7 +215,10 @@ 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 +236,7 @@ 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 +247,9 @@ 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 +263,7 @@ 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 {
@@ -373,6 +359,7 @@ function scheduleInputCompletionCommit(
 export function startRecordCapture(
  _requestId: string,
  sendStep: (step: RecordStepPayload) => void,
+  options: { captureNavigation?: boolean } = {},
 ): RecordCaptureController {
  const emitStep = (step: RecordStepPayload) => {
    sendStep({ page_url: location.href, ...step });
@@ -411,14 +398,17 @@ export function startRecordCapture(
    emitStep({
      op: "fill",
      target: session.target,
+      geometry: captureGeometry(session.element),
      value,
+      commit: session.pendingCommit ?? "blur",
      ...(isPassword ? { redacted: true } : {}),
    });
  };

-  const commitFillSession = () => {
+  const commitFillSession = (commit: "enter" | "suggestion" | "blur" = "blur") => {
    if (!fillSession || composing) return;
    const session = fillSession;
+    session.pendingCommit = commit;
    fillSession = null;
    emitFill(session);
    committedValues.set(session.element, session.lastValue);
@@ -624,6 +614,7 @@ export function startRecordCapture(
    emitStep({
      op: "hover",
      target: hover.target,
+      geometry: captureGeometry(hover.element),
    });
    emittedHoverElements.add(hover.element);
  };
@@ -678,6 +669,7 @@ export function startRecordCapture(
    emitStep({
      op: "click",
      target,
+      geometry: geometryForEventTarget(eventTarget(event)),
      expects_navigation: true,
    });
  };
@@ -779,7 +771,7 @@ export function startRecordCapture(
      scheduleInputCompletionCommit(
        sessionElement,
        syncFillSessionValue,
-        commitFillSession,
+        () => commitFillSession("suggestion"),
        (el) => fillSession?.element === el,
      );
      return;
@@ -839,6 +831,7 @@ export function startRecordCapture(
      emitStep({
        op: "select",
        target: desc,
+        geometry: captureGeometry(target),
        values,
        labels,
        expects_navigation: true,
@@ -879,7 +872,7 @@ export function startRecordCapture(
      };
    }
    if (fillable) {
-      commitFillSession();
+      commitFillSession(event.key === "Enter" ? "enter" : "blur");
    }
    const desc = describeEventTarget(target);
    if (!desc && !event.key) return;
@@ -887,7 +880,7 @@ export function startRecordCapture(
    emitStep({
      op: "press",
      key: event.key,
-      ...(desc ? { target: desc } : {}),
+      ...(desc ? { target: desc, geometry: geometryForEventTarget(target) } : {}),
      ...(modifiers.length ? { modifiers } : {}),
      expects_navigation: event.key === "Enter",
    });
@@ -903,23 +896,33 @@ export function startRecordCapture(
  document.addEventListener("change", onChange, true);
  document.addEventListener("keydown", onKeyDown, true);

-  const urlObserver = new MutationObserver(() => emitNavigateIfChanged());
-  urlObserver.observe(document, { subtree: true, childList: true });
+  const captureNavigation = options.captureNavigation ?? true;
+  const urlObserver = captureNavigation
+    ? new MutationObserver(() => emitNavigateIfChanged())
+    : null;
+  urlObserver?.observe(document, { subtree: true, childList: true });
  const onUrlEvent = () => emitNavigateIfChanged();
-  window.addEventListener("hashchange", onUrlEvent);
-  window.addEventListener("popstate", onUrlEvent);
-  window.addEventListener("pagehide", commitFillSession);
+  // Wrap: passing commitFillSession directly would forward the DOM event as
+  // the `commit` argument and stamp it onto the recorded fill step.
+  const onPageHide = () => commitFillSession();
+  if (captureNavigation) {
+    window.addEventListener("hashchange", onUrlEvent);
+    window.addEventListener("popstate", onUrlEvent);
+  }
+  window.addEventListener("pagehide", onPageHide);

  const originalPushState = history.pushState;
  const originalReplaceState = history.replaceState;
-  history.pushState = function (...args: Parameters<History["pushState"]>) {
-    originalPushState.apply(this, args);
-    emitNavigateIfChanged(navigationActionPending ? true : undefined);
-  };
-  history.replaceState = function (...args: Parameters<History["replaceState"]>) {
-    originalReplaceState.apply(this, args);
-    emitNavigateIfChanged(navigationActionPending ? true : undefined);
-  };
+  if (captureNavigation) {
+    history.pushState = function (...args: Parameters<History["pushState"]>) {
+      originalPushState.apply(this, args);
+      emitNavigateIfChanged(navigationActionPending ? true : undefined);
+    };
+    history.replaceState = function (...args: Parameters<History["replaceState"]>) {
+      originalReplaceState.apply(this, args);
+      emitNavigateIfChanged(navigationActionPending ? true : undefined);
+    };
+  }

  return {
    dispose() {
@@ -933,93 +936,16 @@ export function startRecordCapture(
      document.removeEventListener("compositionend", onCompositionEnd, true);
      document.removeEventListener("change", onChange, true);
      document.removeEventListener("keydown", onKeyDown, true);
-      urlObserver.disconnect();
-      window.removeEventListener("hashchange", onUrlEvent);
-      window.removeEventListener("popstate", onUrlEvent);
-      window.removeEventListener("pagehide", commitFillSession);
-      history.pushState = originalPushState;
-      history.replaceState = originalReplaceState;
+      urlObserver?.disconnect();
+      if (captureNavigation) {
+        window.removeEventListener("hashchange", onUrlEvent);
+        window.removeEventListener("popstate", onUrlEvent);
+      }
+      window.removeEventListener("pagehide", onPageHide);
+      if (captureNavigation) {
+        history.pushState = originalPushState;
+        history.replaceState = originalReplaceState;
+      }
    },
  };
 }
-
-export type RecordContentMessage = RecordStartMessage | RecordStopMessage | RecordCancelMessage;
-
-export function isRecordContentMessage(msg: unknown): msg is RecordContentMessage {
-  return isRecordStartMessage(msg) || isRecordStopMessage(msg) || isRecordCancelMessage(msg);
-}
-
-export function handleRecordContentMessage(
-  message: RecordContentMessage,
-  state: {
-    activeRequestId: string | null;
-    capture: RecordCaptureController | null;
-    setActiveRequestId(id: string | null): void;
-    setCapture(capture: RecordCaptureController | null): void;
-    onStart(requestId: string, startedAtMs?: number): void;
-    onStop(): void;
-  },
-  sendResponse?: (response: RecordStartAck | RecordStopAck) => void,
-): boolean {
-  if (isRecordStartMessage(message)) {
-    if (!knownRecordRequests.has(message.requestId)) {
-      knownRecordRequests.add(message.requestId);
-      failedStepDeliveries.delete(message.requestId);
-    }
-    state.capture?.dispose();
-    state.setCapture(
-      startRecordCapture(message.requestId, (step) => {
-        sendRecordStep(message.requestId, step);
-      }),
-    );
-    state.setActiveRequestId(message.requestId);
-    state.onStart(message.requestId, message.startedAtMs);
-    sendResponse?.({ ok: true });
-    return sendResponse !== undefined;
-  }
-
-  if (isRecordStopMessage(message) || isRecordCancelMessage(message)) {
-    // Require an active recording that matches this requestId — otherwise a
-    // stray STOP/CANCEL (e.g. after teardown) would still run finishStop and
-    // clear overlay state even though nothing was capturing.
-    if (!state.activeRequestId || state.activeRequestId !== message.requestId) {
-      return false;
-    }
-    state.capture?.dispose();
-    state.setCapture(null);
-    const finishStop = () => {
-      state.onStop();
-      state.setActiveRequestId(null);
-    };
-    if (isRecordStopMessage(message) && sendResponse) {
-      const pending = [...(pendingStepSends.get(message.requestId) ?? [])];
-      void Promise.all(pending).then((delivered) => {
-        finishStop();
-        const succeeded = delivered.every(Boolean) && !failedStepDeliveries.has(message.requestId);
-        if (succeeded) {
-          failedStepDeliveries.delete(message.requestId);
-          knownRecordRequests.delete(message.requestId);
-        }
-        sendResponse(
-          succeeded
-            ? { ok: true }
-            : {
-                ok: false,
-                error: "failed to deliver one or more recorded steps",
-              },
-        );
-      });
-      return true;
-    }
-    if (isRecordCancelMessage(message)) {
-      failedStepDeliveries.delete(message.requestId);
-      knownRecordRequests.delete(message.requestId);
-    }
-    finishStop();
-    return false;
-  }
-
-  return false;
-}
-
-export { RECORD_CANCEL, RECORD_START, RECORD_STEP, RECORD_STOP };
@@ -0,0 +1,65 @@
+import {
+  isAcceptedRecordStepAck,
+  RECORD_STEP,
+  type RecordStepMessage,
+  type RecordStepPayload,
+} from "@/lib/record-bridge";
+
+export type SendRecordStepMessage = (message: RecordStepMessage) => Promise<unknown>;
+
+export class RecordStepDelivery {
+  readonly #requestId: string;
+  readonly #producerId: string;
+  readonly #send: SendRecordStepMessage;
+  readonly #pending = new Map<number, RecordStepPayload>();
+  #nextSequence = 1;
+  #tail = Promise.resolve();
+
+  constructor(
+    requestId: string,
+    send: SendRecordStepMessage = (message) => chrome.runtime.sendMessage(message),
+    producerId: string = crypto.randomUUID(),
+  ) {
+    this.#requestId = requestId;
+    this.#producerId = producerId;
+    this.#send = send;
+  }
+
+  enqueue(step: RecordStepPayload): void {
+    const sequence = this.#nextSequence;
+    this.#nextSequence += 1;
+    this.#pending.set(sequence, step);
+    void this.#schedule();
+  }
+
+  async flush(): Promise<boolean> {
+    await this.#tail;
+    await this.#schedule();
+    return this.#pending.size === 0;
+  }
+
+  #schedule(): Promise<void> {
+    const drain = () => this.#drain();
+    this.#tail = this.#tail.then(drain, drain);
+    return this.#tail;
+  }
+
+  async #drain(): Promise<void> {
+    for (const [sequence, step] of this.#pending) {
+      const message: RecordStepMessage = {
+        type: RECORD_STEP,
+        requestId: this.#requestId,
+        producerId: this.#producerId,
+        sequence,
+        step,
+      };
+      try {
+        const response = await this.#send(message);
+        if (!isAcceptedRecordStepAck(response, sequence)) return;
+        this.#pending.delete(sequence);
+      } catch {
+        return;
+      }
+    }
+  }
+}
@@ -0,0 +1,209 @@
+import {
+  markRecordingDocument,
+  type RecordingDocumentMarker,
+  waitForDocumentElement,
+} from "@/lib/recording/document-marker";
+import {
+  isRecordFrameStartMessage,
+  RECORD_FRAME_PORT,
+  RECORD_FRAME_QUERY,
+  RECORD_FRAME_START,
+  type RecordFramePortMessage,
+  type RecordFrameQueryResponse,
+  type RecordFrameStartMessage,
+} from "@/lib/recording/frame-bridge";
+import { type RecordCaptureController, startRecordCapture } from "../record-capture";
+import { RecordStepDelivery } from "../record-step-delivery";
+
+interface ActiveFrameRecording {
+  requestId: string;
+  producerId: string;
+  port: chrome.runtime.Port;
+  delivery: RecordStepDelivery;
+  capture: RecordCaptureController;
+  marker: RecordingDocumentMarker;
+}
+
+const RECORD_FRAME_REGISTER_TIMEOUT_MS = 5_000;
+
+export class RecordFrameAgent {
+  #active: ActiveFrameRecording | null = null;
+  #startPromise: Promise<{ ok: true } | { ok: false; error: string }> | null = null;
+  #disposed = false;
+
+  async start(
+    message: RecordFrameStartMessage,
+  ): Promise<{ ok: true } | { ok: false; error: string }> {
+    if (this.#active?.requestId === message.requestId) return { ok: true };
+    if (this.#disposed) return { ok: false, error: "recording document is disposed" };
+    if (this.#startPromise) {
+      await this.#startPromise;
+      return this.start(message);
+    }
+    if (this.#active) this.cancel(this.#active.requestId);
+    const starting = this.#start(message);
+    this.#startPromise = starting;
+    try {
+      return await starting;
+    } finally {
+      if (this.#startPromise === starting) this.#startPromise = null;
+    }
+  }
+
+  cancel(requestId: string): void {
+    const active = this.#active;
+    if (!active || active.requestId !== requestId) return;
+    active.capture.dispose();
+    active.marker.restore();
+    active.port.disconnect();
+    this.#active = null;
+  }
+
+  dispose(): void {
+    this.#disposed = true;
+    if (this.#active) this.cancel(this.#active.requestId);
+  }
+
+  async #start(
+    message: RecordFrameStartMessage,
+  ): Promise<{ ok: true } | { ok: false; error: string }> {
+    const producerId = crypto.randomUUID();
+    const root = await waitForDocumentElement();
+    if (this.#disposed) return { ok: false, error: "recording document is disposed" };
+    const marker = markRecordingDocument(producerId, root);
+    const port = chrome.runtime.connect({ name: RECORD_FRAME_PORT });
+    try {
+      await registerPort(port, message.requestId, producerId);
+    } catch {
+      marker.restore();
+      port.disconnect();
+      return { ok: false, error: "failed to register recording document" };
+    }
+    if (this.#disposed) {
+      marker.restore();
+      port.disconnect();
+      return { ok: false, error: "recording document is disposed" };
+    }
+
+    const delivery = new RecordStepDelivery(message.requestId, undefined, producerId);
+    const capture = startRecordCapture(
+      message.requestId,
+      (step) => {
+        marker.ensure();
+        delivery.enqueue(step);
+      },
+      { captureNavigation: window.top === window },
+    );
+    const active: ActiveFrameRecording = {
+      requestId: message.requestId,
+      producerId,
+      port,
+      delivery,
+      capture,
+      marker,
+    };
+    this.#active = active;
+    port.onMessage.addListener((raw: unknown) => {
+      const command = raw as Partial<RecordFramePortMessage>;
+      if (command.type === "stop" && command.requestId === active.requestId) {
+        void this.#stop(active, command.commandId);
+      } else if (command.type === "cancel" && command.requestId === active.requestId) {
+        this.cancel(active.requestId);
+      }
+    });
+    port.onDisconnect.addListener(() => {
+      if (this.#active !== active) return;
+      active.capture.dispose();
+      active.marker.restore();
+      this.#active = null;
+    });
+    return { ok: true };
+  }
+
+  async #stop(active: ActiveFrameRecording, commandId: string | undefined): Promise<void> {
+    if (!commandId || this.#active !== active) return;
+    active.capture.dispose();
+    const succeeded = await active.delivery.flush();
+    try {
+      active.port.postMessage({
+        type: "stopped",
+        requestId: active.requestId,
+        commandId,
+        ok: succeeded,
+        ...(succeeded ? {} : { error: "failed to deliver one or more recorded steps" }),
+      } satisfies RecordFramePortMessage);
+    } catch {
+      return;
+    }
+    if (!succeeded || this.#active !== active) return;
+    active.marker.restore();
+    this.#active = null;
+    active.port.disconnect();
+  }
+}
+
+function registerPort(
+  port: chrome.runtime.Port,
+  requestId: string,
+  producerId: string,
+): Promise<void> {
+  return new Promise((resolve, reject) => {
+    const timer = setTimeout(() => {
+      cleanup();
+      reject(new Error("recording document registration timed out"));
+    }, RECORD_FRAME_REGISTER_TIMEOUT_MS);
+    const cleanup = () => {
+      clearTimeout(timer);
+      port.onMessage.removeListener(onMessage);
+      port.onDisconnect.removeListener(onDisconnect);
+    };
+    const onMessage = (raw: unknown) => {
+      const message = raw as Partial<RecordFramePortMessage>;
+      if (
+        message.type !== "ready_ack" ||
+        message.requestId !== requestId ||
+        message.producerId !== producerId
+      ) {
+        return;
+      }
+      cleanup();
+      resolve();
+    };
+    const onDisconnect = () => {
+      cleanup();
+      reject(new Error("recording document port disconnected"));
+    };
+    port.onMessage.addListener(onMessage);
+    port.onDisconnect.addListener(onDisconnect);
+    port.postMessage({ type: "ready", requestId, producerId } satisfies RecordFramePortMessage);
+  });
+}
+
+export function attachRecordFrameAgent(): () => void {
+  const agent = new RecordFrameAgent();
+  const onMessage = (
+    message: unknown,
+    _sender: chrome.runtime.MessageSender,
+    sendResponse: (response: { ok: true } | { ok: false; error: string }) => void,
+  ) => {
+    if (!isRecordFrameStartMessage(message)) return false;
+    void agent.start(message).then(sendResponse);
+    return true;
+  };
+  chrome.runtime.onMessage.addListener(onMessage);
+  void chrome.runtime
+    .sendMessage({ type: RECORD_FRAME_QUERY })
+    .then((response: RecordFrameQueryResponse | undefined) => {
+      if (!response?.active || !response.requestId || response.startedAtMs === undefined) return;
+      return agent.start({
+        type: RECORD_FRAME_START,
+        requestId: response.requestId,
+        startedAtMs: response.startedAtMs,
+      });
+    })
+    .catch(() => {});
+  return () => {
+    chrome.runtime.onMessage.removeListener(onMessage);
+    agent.dispose();
+  };
+}
@@ -4,7 +4,9 @@ import { ConnectionController } from "@/lib/connection-controller";
 import { startHeartbeat } from "@/lib/heartbeat";
 import {
  getConnectionEnabled,
+  getDaemonPort,
  setConnectionEnabled as persistConnectionEnabled,
+  STORAGE_KEYS,
  setLabel,
 } from "@/lib/instance-id";
 import { startKeepalive } from "@/lib/keepalive";
@@ -21,6 +23,7 @@ import {
  type OverlayMode,
 } from "@/lib/overlay-bridge";
 import { POPUP_PORT_NAME, type PopupInbound, type PopupOutbound } from "@/lib/popup-bridge";
+import { recordFrameCoordinator } from "@/lib/recording/frame-coordinator";
 import { attachSessionsLiveFlag } from "@/lib/sessions-live-flag";
 import { createDisconnectCleanup } from "@/session-manager/disconnect-cleanup";
 import { attachSessionEventHandler } from "@/session-manager/event-handler";
@@ -38,7 +41,9 @@ import {
  attachRecordFinishListener,
  attachRecordQueryListener,
  attachRecordStepListener,
+  type RecordRuntimeDeps,
 } from "@/tools/record";
+import { resolveDaemonWsUrl } from "@/transport/daemon-endpoint";
 import { detectBrowserMeta } from "@/transport/handshake";
 import type { Transport } from "@/transport/transport";
 import { WSTransport } from "@/transport/ws-transport";
@@ -52,6 +57,27 @@ export default defineBackground(() => {
  let overlayGeneration = 0;
  const controlModes = new Map<string, OverlayMode>();

+  async function applyDaemonPort(port: number): Promise<void> {
+    const url = resolveDaemonWsUrl(port);
+    if (!transport.setUrl(url)) return;
+    await transport.disconnect();
+    if (!controller.isConnectionEnabled) return;
+    try {
+      await transport.connect();
+    } catch (err) {
+      console.debug("[browser-skill] reconnect after port change failed", err);
+    }
+  }
+
+  if (typeof chrome !== "undefined" && chrome.storage?.onChanged) {
+    chrome.storage.onChanged.addListener((changes, areaName) => {
+      if (areaName !== "local") return;
+      const change = changes[STORAGE_KEYS.DAEMON_PORT];
+      if (!change || typeof change.newValue !== "number") return;
+      void applyDaemonPort(change.newValue);
+    });
+  }
+
  function setControlMode(sessionId: string, mode: OverlayMode): void {
    if (controlModes.get(sessionId) === mode) return;
    controlModes.set(sessionId, mode);
@@ -145,10 +171,33 @@ export default defineBackground(() => {
      void sessionsLive.syncFromManager();
    },
  });
+  const recordDeps = {
+    tabsApi: chrome.tabs,
+    cdp,
+    frameCoordinator: recordFrameCoordinator,
+    sendToTab: (tabId: number, msg: Parameters<typeof chrome.tabs.sendMessage>[1]) =>
+      chrome.tabs.sendMessage(tabId, msg),
+    bypassOverlay: async (tabId: number, enabled: boolean) => {
+      try {
+        await chrome.tabs.sendMessage(tabId, {
+          type: OVERLAY_AUTOMATION_BYPASS,
+          enabled,
+        });
+      } catch {
+        // Content script may be unavailable on restricted pages.
+      }
+    },
+  } satisfies RecordRuntimeDeps;
+  recordFrameCoordinator.attach();
+  attachRecordStepListener(recordDeps);
+  attachRecordFinishListener(recordDeps);
+  attachRecordQueryListener(recordDeps);
+
  const dispatcher = new ToolDispatcher({
    transport,
    sessions,
    cdp,
+    recording: recordDeps,
    onSessionsChanged: onOverlaySessionStateChanged,
    onBrowserControlResumed,
    approveBorrow: (ctx) =>
@@ -170,27 +219,6 @@ export default defineBackground(() => {
    }),
  });
  dispatcher.start();
-  const recordDeps = {
-    tabsApi: chrome.tabs,
-    sendToTab: (tabId: number, msg: Parameters<typeof chrome.tabs.sendMessage>[1]) =>
-      chrome.tabs.sendMessage(tabId, msg),
-    bypassOverlay: async (tabId: number, enabled: boolean) => {
-      try {
-        await chrome.tabs.sendMessage(tabId, {
-          type: OVERLAY_AUTOMATION_BYPASS,
-          enabled,
-        });
-      } catch {
-        // Content script may be unavailable on restricted pages.
-      }
-    },
-  };
-  // Message listeners stay up (cheap; fire only for record message types).
-  // Tab / webNavigation observation attaches lazily while a recording is
-  // active — see ensureBrowserObservationListeners in tools/record.ts.
-  attachRecordStepListener();
-  attachRecordFinishListener(recordDeps);
-  attachRecordQueryListener(recordDeps);
  if (typeof chrome.notifications?.onClicked?.addListener === "function") {
    attachBorrowNotificationClickHandler({
      onClicked: chrome.notifications.onClicked,
@@ -275,6 +303,8 @@ export default defineBackground(() => {

  void (async () => {
    const connectionEnabled = await getConnectionEnabled();
+    const port = await getDaemonPort();
+    transport.setUrl(resolveDaemonWsUrl(port));
    await controller.attach(transport, detectBrowserMeta(), connectionEnabled, {
      beforeDisconnect: async () => {
        const report = await cleanupAfterDisconnect();
@@ -341,11 +371,6 @@ export default defineBackground(() => {
      if (msg && typeof msg === "object" && "kind" in msg) {
        if (msg.kind === "set_label") {
          void setLabel(msg.value).then(() => controller.refreshLabel());
-        } else if (msg.kind === "set_port") {
-          // Placeholder for the future custom-port UI; warn loudly so
-          // any reintroduced popup control is caught instead of
-          // silently doing nothing (review M4/M5 C2).
-          console.warn("[browser-skill] set_port is not wired yet; ignoring", msg.value);
        } else if (msg.kind === "set_connection_enabled") {
          void controller
            .setConnectionEnabled(msg.value)
@@ -11,11 +11,6 @@ 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";
-import {
-  handleRecordContentMessage,
-  isRecordContentMessage,
-  type RecordCaptureController,
-} from "@/content/record-capture";
 import {
  type CaptureSuppressAck,
  type CaptureSuppressMessage,
@@ -45,11 +40,17 @@ import {
 } from "@/lib/overlay-bridge";
 import { sendInterrupt } from "@/lib/overlay-interrupt-client";
 import {
+  isRecordCancelMessage,
+  isRecordStartMessage,
+  isRecordStopMessage,
  RECORD_FINISH,
  RECORD_QUERY,
+  type RecordCancelMessage,
  type RecordQueryResponse,
  type RecordStartAck,
+  type RecordStartMessage,
  type RecordStopAck,
+  type RecordStopMessage,
 } from "@/lib/record-bridge";
 import type {
  BorrowCancelMessage,
@@ -69,7 +70,6 @@ export default defineContentScript({
    if (window.top !== window) return;

    const overlays = new OverlayController();
-    let recordCapture: RecordCaptureController | null = null;
    let activeRecordRequestId: string | null = null;
    let reactRoot: ReactDOM.Root | null = null;
    let overlayHost: HTMLElement | null = null;
@@ -228,8 +228,6 @@ export default defineContentScript({
      if (previousHelp) {
        void sendHelpFinish(previousHelp.id, "cancelled");
      }
-      recordCapture?.dispose();
-      recordCapture = null;
      activeRecordRequestId = null;
      renderAll();
    }
@@ -259,6 +257,9 @@ export default defineContentScript({
        | HelpRequestMessage
        | HelpCancelMessage
        | CaptureSuppressMessage
+        | RecordStartMessage
+        | RecordStopMessage
+        | RecordCancelMessage
        | OverlayAgentOverlayResetMessage
        | OverlayAgentStateMessage
        | OverlayAutomationBypassMessage,
@@ -269,41 +270,32 @@ export default defineContentScript({
        return captureSuppress.handleMessage(message, sendResponse);
      }

-      if (isRecordContentMessage(message)) {
-        const needsAsync = handleRecordContentMessage(
-          message,
-          {
-            activeRequestId: activeRecordRequestId,
-            capture: recordCapture,
-            setActiveRequestId: (id) => {
-              activeRecordRequestId = id;
-            },
-            setCapture: (capture) => {
-              recordCapture = capture;
-            },
-            onStart: (requestId, startedAtMs) => {
-              overlays.setAgentRecordRequest({
-                id: requestId,
-                ...(typeof startedAtMs === "number" ? { startedAtMs } : {}),
-                onFinish: () => {
-                  void chrome.runtime.sendMessage({
-                    type: RECORD_FINISH,
-                    requestId,
-                  });
-                },
-              });
-              renderAll();
-            },
-            onStop: () => {
-              overlays.clearAgentRecordRequest(activeRecordRequestId ?? undefined);
-              renderAll();
-            },
+      if (isRecordStartMessage(message)) {
+        activeRecordRequestId = message.requestId;
+        overlays.setAgentRecordRequest({
+          id: message.requestId,
+          ...(typeof message.startedAtMs === "number" ? { startedAtMs: message.startedAtMs } : {}),
+          onFinish: () => {
+            void chrome.runtime.sendMessage({
+              type: RECORD_FINISH,
+              requestId: message.requestId,
+            });
          },
-          sendResponse as unknown as
-            | ((response: RecordStartAck | RecordStopAck) => void)
-            | undefined,
-        );
-        return needsAsync;
+        });
+        renderAll();
+        (sendResponse as unknown as (response: RecordStartAck) => void)({ ok: true });
+        return false;
+      }
+
+      if (isRecordStopMessage(message) || isRecordCancelMessage(message)) {
+        if (activeRecordRequestId !== message.requestId) return false;
+        overlays.clearAgentRecordRequest(message.requestId);
+        activeRecordRequestId = null;
+        renderAll();
+        if (isRecordStopMessage(message)) {
+          (sendResponse as unknown as (response: RecordStopAck) => void)({ ok: true });
+        }
+        return false;
      }

      if (
@@ -526,9 +518,6 @@ export default defineContentScript({
      chrome.runtime.onMessage.removeListener(onMessage);
      chrome.storage.onChanged.removeListener(onStorageChange);
      window.removeEventListener("pageshow", onPageShow);
-      // Restore history hooks / remove capture listeners before the CS unloads.
-      recordCapture?.dispose();
-      recordCapture = null;
      activeRecordRequestId = null;
    });
  },
@@ -2,6 +2,7 @@ import { cleanup, fireEvent, render, screen, waitFor } from "@testing-library/re
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import type { SnapshotInfo } from "@/lib/connection-controller";
 import { STORAGE_KEYS } from "@/lib/instance-id";
+import { DEFAULT_DAEMON_PORT } from "@/transport/daemon-endpoint";
 import { EXTENSION_VERSION } from "@/transport/handshake";
 import { App } from "./App";
 import { useConnectionState } from "./use-connection-state";
@@ -66,9 +67,32 @@ describe("App", () => {
    render(<App />);

    expect(screen.getByText("未连接")).toBeTruthy();
+    expect(screen.getByText("无法连接，请确认 daemon 已启动且端口一致。")).toBeTruthy();
    expect(screen.queryByText("请先打开 BrowserSkill。")).toBeNull();
  });

+  it("shows the connection switch off and hides transport errors when disconnected", () => {
+    mockUseConnectionState.mockReturnValue({
+      snapshot: {
+        ...baseSnapshot,
+        lastError: "[WSTransport] disconnect during connect",
+      },
+      statusState: "disconnected",
+      setLabel,
+      setConnectionEnabled,
+    });
+
+    render(<App />);
+
+    expect(screen.getByText("未连接")).toBeTruthy();
+    expect(screen.getByText("无法连接，请确认 daemon 已启动且端口一致。")).toBeTruthy();
+    expect(screen.queryByText("端口不匹配")).toBeNull();
+    expect(
+      screen.getByRole("switch", { name: "BrowserSkill 连接" }).getAttribute("aria-checked"),
+    ).toBe("false");
+    expect(screen.queryByText("[WSTransport] disconnect during connect")).toBeNull();
+  });
+
  it("does not render record UI on the main view", () => {
    render(<App />);

@@ -136,6 +160,13 @@ describe("App", () => {
  });

  it("renders the connection toggle with switch semantics", () => {
+    mockUseConnectionState.mockReturnValue({
+      snapshot: { ...baseSnapshot, state: "connected" },
+      statusState: "connected",
+      setLabel,
+      setConnectionEnabled,
+    });
+
    render(<App />);

    const toggle = screen.getByRole("switch", { name: "BrowserSkill 连接" });
@@ -143,6 +174,13 @@ describe("App", () => {
  });

  it("calls setConnectionEnabled(false) when the toggle is turned off", () => {
+    mockUseConnectionState.mockReturnValue({
+      snapshot: { ...baseSnapshot, state: "connected" },
+      statusState: "connected",
+      setLabel,
+      setConnectionEnabled,
+    });
+
    render(<App />);

    fireEvent.click(screen.getByRole("switch", { name: "BrowserSkill 连接" }));
@@ -160,6 +198,7 @@ describe("App", () => {
    render(<App />);

    expect(screen.getByText("连接已关闭")).toBeTruthy();
+    expect(screen.queryByText("无法连接，请确认 daemon 已启动且端口一致。")).toBeNull();
    expect(
      screen.getByRole("switch", { name: "BrowserSkill 连接" }).getAttribute("aria-checked"),
    ).toBe("false");
@@ -200,6 +239,9 @@ describe("App", () => {
    expect(copied).toContain("--browser 03c3e47f");
    expect(copied).toContain('--purpose "发布 wiki 文档"');
    expect(copied).not.toMatch(/bsk record start[^\n]*--url/);
+    expect(copied).toContain("./trace");
+    expect(copied).toContain("trace.json");
+    expect(copied).toContain("states/");
    // Button label stays static; a transient toast confirms the copy.
    expect(copyButton.textContent).toContain("复制录制指令");
    await waitFor(() => expect(screen.getByRole("status").textContent).toContain("已复制"));
@@ -244,6 +286,41 @@ describe("App", () => {
    expect(copyButton.getAttribute("disabled")).not.toBeNull();
    expect(screen.getByText("连接后可用")).toBeTruthy();
  });
+
+  it("treats protocol drift as still connected and prompts an upgrade", async () => {
+    mockUseConnectionState.mockReturnValue({
+      snapshot: {
+        ...baseSnapshot,
+        state: "version_skew",
+        instanceId: "03c3e47f",
+        handshake: {
+          server: "bh",
+          version: mockDaemonVersion,
+          protocol_version: "1.0",
+        },
+      },
+      statusState: "version_skew",
+      setLabel,
+      setConnectionEnabled,
+    });
+
+    render(<App />);
+
+    expect(screen.getByText("已连接")).toBeTruthy();
+    expect(screen.getByText("可升级")).toBeTruthy();
+    expect(screen.queryByText("协议不一致")).toBeNull();
+    expect(screen.queryByText("Action needed")).toBeNull();
+    expect(screen.queryByText("兼容")).toBeNull();
+    const warning = screen.getByText(/协议版本不同，请及时升级/);
+    expect(warning.textContent).toContain("CLI 协议");
+    expect(warning.textContent).toContain("扩展协议");
+
+    openRecordView();
+    const copyButton = screen.getByRole("button", { name: "复制录制指令" });
+    expect(copyButton.getAttribute("disabled")).toBeNull();
+    fireEvent.click(copyButton);
+    expect(navigator.clipboard.writeText).toHaveBeenCalledTimes(1);
+  });
 });

 describe("control hints toggle", () => {
@@ -316,14 +393,20 @@ describe("control hints toggle", () => {

    const info = await screen.findByRole("button", { name: "控制提示说明" });
    expect(info).toBeTruthy();
-    const tooltip = screen.getByRole("tooltip");
-    expect(tooltip.textContent).toBe("Agent 控制页面时显示提示条和橙色闪光。");
+    const tooltip = screen.getByText("Agent 控制页面时显示提示条和橙色闪光。");
+    expect(tooltip.getAttribute("role")).toBe("tooltip");
    // Hidden until the info button is hovered or focused.
    expect(tooltip.className).toContain("opacity-0");
  });

  it("uses the same switch component and size for both settings rows", async () => {
    stubChromeStorage();
+    mockUseConnectionState.mockReturnValue({
+      snapshot: { ...baseSnapshot, state: "connected" },
+      statusState: "connected",
+      setLabel: vi.fn(),
+      setConnectionEnabled: vi.fn(),
+    });

    render(<App />);

@@ -336,3 +419,109 @@ describe("control hints toggle", () => {
    expect(hintsToggle.className).toBe(connectionToggle.className);
  });
 });
+
+describe("daemon port input", () => {
+  function stubChromeStorage(initial: Record<string, unknown> = {}) {
+    const store = { ...initial };
+    vi.stubGlobal("chrome", {
+      runtime: { lastError: undefined },
+      storage: {
+        local: {
+          get: (keys: string | string[], cb: (items: Record<string, unknown>) => void) => {
+            const items: Record<string, unknown> = {};
+            for (const k of Array.isArray(keys) ? keys : [keys]) {
+              if (k in store) items[k] = store[k];
+            }
+            cb(items);
+          },
+          set: (items: Record<string, unknown>, cb?: () => void) => {
+            Object.assign(store, items);
+            cb?.();
+          },
+        },
+        onChanged: {
+          addListener: vi.fn(),
+          removeListener: vi.fn(),
+        },
+      },
+    });
+    return store;
+  }
+
+  afterEach(() => {
+    cleanup();
+    vi.unstubAllGlobals();
+  });
+
+  it("prefills the port from storage", async () => {
+    stubChromeStorage({ [STORAGE_KEYS.DAEMON_PORT]: 53200 });
+
+    render(<App />);
+
+    const input = await screen.findByRole("textbox", { name: "连接端口" });
+    await waitFor(() => expect((input as HTMLInputElement).value).toBe("53200"));
+  });
+
+  it("persists a valid port on blur", async () => {
+    const store = stubChromeStorage();
+
+    render(<App />);
+
+    const input = await screen.findByRole("textbox", { name: "连接端口" });
+    fireEvent.change(input, { target: { value: "53200" } });
+    fireEvent.blur(input);
+
+    expect(store[STORAGE_KEYS.DAEMON_PORT]).toBe(53200);
+    expect((input as HTMLInputElement).value).toBe("53200");
+  });
+
+  it("persists a valid port when Enter blurs the field", async () => {
+    const store = stubChromeStorage();
+
+    render(<App />);
+
+    const input = await screen.findByRole("textbox", { name: "连接端口" });
+    fireEvent.change(input, { target: { value: "53200" } });
+    fireEvent.keyDown(input, { key: "Enter" });
+
+    expect(store[STORAGE_KEYS.DAEMON_PORT]).toBe(53200);
+  });
+
+  it("shows an error and does not write invalid ports", async () => {
+    const store = stubChromeStorage();
+
+    render(<App />);
+
+    const input = await screen.findByRole("textbox", { name: "连接端口" });
+    fireEvent.change(input, { target: { value: "abc" } });
+    fireEvent.blur(input);
+
+    expect(screen.getByText("请输入 1 到 65535 之间的端口号。")).toBeTruthy();
+    expect(store[STORAGE_KEYS.DAEMON_PORT]).toBeUndefined();
+  });
+
+  it("stores the default port when the field is cleared", async () => {
+    const store = stubChromeStorage({ [STORAGE_KEYS.DAEMON_PORT]: 53200 });
+
+    render(<App />);
+
+    const input = await screen.findByRole("textbox", { name: "连接端口" });
+    fireEvent.change(input, { target: { value: "" } });
+    fireEvent.blur(input);
+
+    expect(store[STORAGE_KEYS.DAEMON_PORT]).toBe(DEFAULT_DAEMON_PORT);
+    expect((input as HTMLInputElement).value).toBe(String(DEFAULT_DAEMON_PORT));
+  });
+
+  it("keeps the port hint copy in an accessible info tooltip", async () => {
+    stubChromeStorage();
+
+    render(<App />);
+
+    const info = await screen.findByRole("button", { name: "连接端口说明" });
+    expect(info).toBeTruthy();
+    const tooltip = screen.getByText("扩展通过此端口连接本机 daemon。非必要请勿修改。");
+    expect(tooltip.getAttribute("role")).toBe("tooltip");
+    expect(tooltip.className).toContain("opacity-0");
+  });
+});
@@ -15,6 +15,7 @@ import { POPUP_FEATURES, type PopupView } from "./features";
 import { Switch } from "./switch";
 import { type PopupStatusState, useConnectionState } from "./use-connection-state";
 import { useControlHintsHidden } from "./use-control-hints-hidden";
+import { useDaemonPort } from "./use-daemon-port";

 const STATE_LABEL_KEYS = {
  disconnected: "popup.stateLabel.disconnected",
@@ -41,6 +42,12 @@ export function App() {
  const { t } = useTranslation("extension");
  const { snapshot, statusState, setConnectionEnabled } = useConnectionState();
  const [controlHintsHidden, setControlHintsHidden] = useControlHintsHidden();
+  const {
+    draft: daemonPortDraft,
+    setDraft: setDaemonPortDraft,
+    commit: commitDaemonPort,
+    invalid: daemonPortInvalid,
+  } = useDaemonPort();
  const [view, setView] = useState<PopupView>("main");
  const [copiedInstanceId, setCopiedInstanceId] = useState(false);
  const [purposeDraft, setPurposeDraft] = useState("");
@@ -79,6 +86,8 @@ export function App() {
  }, [copiedTick]);

  const isSkewed = statusState === "version_skew";
+  const isDisconnected = statusState === "disconnected";
+  const connectionLive = statusState === "connected" || isSkewed;
  const daemonVersion = snapshot.handshake?.version ?? "—";
  const daemonProtocol = snapshot.handshake?.protocol_version ?? "—";
  const extensionVersion = snapshot.extensionVersion || "—";
@@ -90,7 +99,7 @@ export function App() {
    setCopiedInstanceId(true);
  };

-  const recordReady = statusState === "connected" && Boolean(snapshot.instanceId);
+  const recordReady = connectionLive && Boolean(snapshot.instanceId);
  const recordPurpose = purposeDraft.trim();
  const recordStartUrl = startUrlDraft.trim();
  const recordCommand = snapshot.instanceId
@@ -197,21 +206,29 @@ export function App() {
                  {t(STATE_BADGE_KEYS[statusState])}
                </Badge>
                <Switch
-                  checked={snapshot.connectionEnabled}
+                  checked={snapshot.connectionEnabled && !isDisconnected}
                  onCheckedChange={setConnectionEnabled}
                  aria-label={t("popup.connectionToggleTitle")}
                  data-slot="popup-connection-toggle"
                />
              </div>
            </div>
+            {isDisconnected && (
+              <p
+                className="mt-2 text-xs leading-snug text-muted-foreground"
+                data-slot="popup-daemon-unreachable"
+              >
+                {t("popup.daemonUnreachable")}
+              </p>
+            )}
            {isSkewed && (
              <p
-                className="mt-2 text-xs leading-snug text-amber-600 dark:text-amber-400"
+                className="mt-2 text-xs leading-snug text-muted-foreground"
                data-slot="popup-version-skew-warning"
              >
                {t("popup.versionSkewWarning", {
                  extensionProtocol: PROTOCOL_VERSION,
-                  daemonProtocol,
+                  cliProtocol: daemonProtocol,
                })}
              </p>
            )}
@@ -252,7 +269,66 @@ export function App() {
            </div>
          </section>

-          {snapshot.lastError && (
+          <section
+            className="rounded-xl border border-border/80 bg-card/60 px-3 py-2.5"
+            data-slot="popup-daemon-port-card"
+          >
+            <div className="flex items-center justify-between gap-2">
+              <span className="flex min-w-0 items-center gap-1">
+                <Label
+                  htmlFor="bh-daemon-port"
+                  className="truncate text-sm font-medium leading-normal"
+                >
+                  {t("popup.daemonPortLabel")}
+                </Label>
+                <span className="group relative inline-flex shrink-0">
+                  <button
+                    type="button"
+                    aria-label={t("popup.daemonPortInfoLabel")}
+                    data-slot="popup-daemon-port-info"
+                    className="flex size-4 items-center justify-center rounded-full text-muted-foreground/70 transition-colors hover:text-muted-foreground focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/50"
+                  >
+                    <RiInformationLine className="size-3.5" aria-hidden />
+                  </button>
+                  <span
+                    role="tooltip"
+                    className="pointer-events-none absolute bottom-full left-0 z-10 mb-1.5 w-56 whitespace-normal rounded-md bg-foreground/65 px-2 py-1 text-[10px] font-medium leading-snug text-background opacity-0 shadow-md backdrop-blur-sm transition-opacity group-hover:opacity-100 group-focus-within:opacity-100"
+                  >
+                    {t("popup.daemonPortHint")}
+                  </span>
+                </span>
+              </span>
+              <Input
+                id="bh-daemon-port"
+                type="text"
+                inputMode="numeric"
+                value={daemonPortDraft}
+                onChange={(event: ChangeEvent<HTMLInputElement>) =>
+                  setDaemonPortDraft(event.target.value)
+                }
+                onBlur={commitDaemonPort}
+                onKeyDown={(event) => {
+                  if (event.key === "Enter") {
+                    event.preventDefault();
+                    commitDaemonPort();
+                  }
+                }}
+                className="mt-0 h-7.5 w-19 shrink-0 rounded-md px-2 py-0 text-center text-sm leading-none shadow-none"
+                aria-invalid={daemonPortInvalid || undefined}
+                data-slot="popup-daemon-port-input"
+              />
+            </div>
+            {daemonPortInvalid && (
+              <p
+                className="mt-1.5 text-[11px] leading-snug text-destructive"
+                data-slot="popup-daemon-port-error"
+              >
+                {t("popup.daemonPortInvalid")}
+              </p>
+            )}
+          </section>
+
+          {snapshot.lastError && !isDisconnected && (
            <div
              className="rounded-lg border border-destructive/25 bg-destructive/10 px-3 py-2 text-xs leading-snug text-destructive"
              data-slot="popup-error"
@@ -40,13 +40,8 @@ const FALLBACK_SNAPSHOT: SnapshotInfo = {
 /**
 * Live snapshot of the background's `ConnectionController` for popup UI.
 *
- * Posts `set_label` mutations back to the background; the incoming
- * snapshot stream reflects the canonical state. The `set_port` channel
- * is defined by the popup-bridge but is not currently routed to the
- * background — wiring it requires `ConnectionController` to swap its
- * Transport URL and persist the chosen port. Tracked for a follow-up
- * milestone; the popup intentionally does not expose a control until
- * the underlying support lands (review M4/M5 C2).
+ * Posts `set_label` and `set_connection_enabled` mutations back to the
+ * background; the incoming snapshot stream reflects the canonical state.
 */
 export function useConnectionState(): {
  snapshot: SnapshotInfo;
@@ -0,0 +1,71 @@
+import { useCallback, useEffect, useRef, useState } from "react";
+import { getDaemonPort, STORAGE_KEYS, setDaemonPort } from "@/lib/instance-id";
+import { parseDaemonPortInput } from "@/transport/daemon-endpoint";
+
+/**
+ * Popup-side daemon port preference stored in `chrome.storage.local`.
+ * Commits on blur, Enter, and pagehide.
+ */
+export function useDaemonPort(): {
+  draft: string;
+  setDraft: (value: string) => void;
+  commit: () => void;
+  invalid: boolean;
+} {
+  const [draft, setDraftState] = useState("");
+  const [invalid, setInvalid] = useState(false);
+  const draftRef = useRef(draft);
+  draftRef.current = draft;
+
+  useEffect(() => {
+    if (typeof chrome === "undefined" || !chrome.storage?.local) return undefined;
+    let cancelled = false;
+    getDaemonPort()
+      .then((port) => {
+        if (!cancelled) setDraftState(String(port));
+      })
+      .catch((err) => {
+        console.debug("[browser-skill] daemon port read failed", err);
+      });
+    const onChanged = (changes: Record<string, chrome.storage.StorageChange>, areaName: string) => {
+      if (areaName !== "local") return;
+      const change = changes[STORAGE_KEYS.DAEMON_PORT];
+      if (change && typeof change.newValue === "number") {
+        setDraftState(String(change.newValue));
+        setInvalid(false);
+      }
+    };
+    chrome.storage.onChanged.addListener(onChanged);
+    return () => {
+      cancelled = true;
+      chrome.storage.onChanged.removeListener(onChanged);
+    };
+  }, []);
+
+  const commit = useCallback(() => {
+    const parsed = parseDaemonPortInput(draftRef.current);
+    if (parsed === null) {
+      setInvalid(true);
+      return;
+    }
+    setInvalid(false);
+    setDraftState(String(parsed));
+    if (typeof chrome === "undefined" || !chrome.storage?.local) return;
+    setDaemonPort(parsed).catch((err) => {
+      console.debug("[browser-skill] daemon port write failed", err);
+    });
+  }, []);
+
+  useEffect(() => {
+    const onPageHide = () => commit();
+    window.addEventListener("pagehide", onPageHide);
+    return () => window.removeEventListener("pagehide", onPageHide);
+  }, [commit]);
+
+  const setDraft = useCallback((value: string) => {
+    setDraftState(value);
+    setInvalid(false);
+  }, []);
+
+  return { draft, setDraft, commit, invalid };
+}
@@ -0,0 +1,14 @@
+import { attachRecordFrameAgent } from "@/content/recording/frame-agent";
+
+export default defineContentScript({
+  matches: ["<all_urls>"],
+  runAt: "document_start",
+  allFrames: true,
+  matchAboutBlank: true,
+  matchOriginAsFallback: true,
+
+  main(ctx) {
+    const dispose = attachRecordFrameAgent();
+    ctx.onInvalidated(dispose);
+  },
+});
@@ -26,20 +26,20 @@ function handshake(
 }

 describe("computeConnectedState (protocol-based compat)", () => {
-  it("returns connected when protocol strings match", () => {
-    expect(computeConnectedState(handshake("1.0", "1.0"), MIN_COMPATIBLE_PROTOCOL)).toEqual({
+  it("returns connected when daemon protocol equals extension protocol", () => {
+    expect(computeConnectedState(handshake("1.1", "1.0"), MIN_COMPATIBLE_PROTOCOL)).toEqual({
      kind: "connected",
    });
  });

  it("returns version_skew when daemon protocol minor is newer", () => {
-    expect(computeConnectedState(handshake("1.1", "1.0"))).toEqual({
+    expect(computeConnectedState(handshake("1.2", "1.0"))).toEqual({
      kind: "version_skew",
    });
  });

  it("returns version_skew when daemon protocol string differs but floor is satisfied", () => {
-    expect(computeConnectedState(handshake("1", "1.0"))).toEqual({
+    expect(computeConnectedState(handshake("1.1.0", "1.0"))).toEqual({
      kind: "version_skew",
    });
  });
@@ -53,7 +53,7 @@ describe("computeConnectedState (protocol-based compat)", () => {
  });

  it("rejects when extension is below daemon min_compatible_protocol", () => {
-    const result = computeConnectedState(handshake("1.0", "1.5"));
+    const result = computeConnectedState(handshake("1.1", "1.5"));
    expect(result.kind).toBe("rejected");
    if (result.kind === "rejected") {
      expect(result.reason).toContain("min_compatible_protocol");
@@ -65,7 +65,7 @@ describe("computeConnectedState (protocol-based compat)", () => {
    const result = computeConnectedState({
      server: "browser-skill-daemon",
      version: "0.1.0",
-      protocol_version: "1.0",
+      protocol_version: "1.1",
      min_compatible_peer: "0.1.0",
    });
    expect(result).toEqual({ kind: "connected" });
@@ -80,7 +80,7 @@ describe("computeConnectedState (protocol-based compat)", () => {
  });

  it("rejects malformed daemon min_compatible_protocol with a daemon-floor reason", () => {
-    const result = computeConnectedState(handshake("1.0", "not-a-protocol"));
+    const result = computeConnectedState(handshake("1.1", "not-a-protocol"));
    expect(result.kind).toBe("rejected");
    if (result.kind === "rejected") {
      expect(result.reason).toContain("daemon min_compatible_protocol");
@@ -242,11 +242,11 @@ describe("ConnectionController connectionEnabled", () => {
    const second = transport.send.mock.calls[1]?.[0] as { id: string };
    expect(second.id).not.toBe(first.id);

-    transport.emitMessage({ id: first.id, result: handshake("1.0", "1.0") });
+    transport.emitMessage({ id: first.id, result: handshake("1.1", "1.0") });
    await Promise.resolve();
    expect(controller.snapshot().state).not.toBe("connected");

-    transport.emitMessage({ id: second.id, result: handshake("1.0", "1.0") });
+    transport.emitMessage({ id: second.id, result: handshake("1.1", "1.0") });
    await vi.waitFor(() => expect(controller.snapshot().state).toBe("connected"));
  });
 });
@@ -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 }),
+    );
+  });
+});
@@ -1,12 +1,15 @@
 import { describe, expect, it, vi } from "vitest";
+import { DEFAULT_DAEMON_PORT } from "@/transport/daemon-endpoint";
 import {
  getConnectionEnabled,
  getControlHintsHidden,
+  getDaemonPort,
  getLabel,
  getOrCreateInstanceId,
  STORAGE_KEYS,
  setConnectionEnabled,
  setControlHintsHidden,
+  setDaemonPort,
  setLabel,
 } from "../instance-id";

@@ -117,4 +120,21 @@ describe("instance-id", () => {
    expect(store[STORAGE_KEYS.CONTROL_HINTS_HIDDEN]).toBe(true);
    expect(await getControlHintsHidden(backend)).toBe(true);
  });
+
+  it("getDaemonPort returns default when storage is empty", async () => {
+    const { backend } = fakeStorage();
+    expect(await getDaemonPort(backend)).toBe(DEFAULT_DAEMON_PORT);
+  });
+
+  it("getDaemonPort normalizes invalid stored values to default", async () => {
+    const { backend } = fakeStorage({ [STORAGE_KEYS.DAEMON_PORT]: 0 });
+    expect(await getDaemonPort(backend)).toBe(DEFAULT_DAEMON_PORT);
+  });
+
+  it("setDaemonPort persists the value retrievable by getDaemonPort", async () => {
+    const { backend, store } = fakeStorage();
+    await setDaemonPort(53200, backend);
+    expect(store[STORAGE_KEYS.DAEMON_PORT]).toBe(53200);
+    expect(await getDaemonPort(backend)).toBe(53200);
+  });
 });
@@ -0,0 +1,32 @@
+import { describe, expect, it } from "vitest";
+import {
+  isAcceptedRecordStepAck,
+  isRecordStepMessage,
+  RECORD_STEP,
+  type RecordStepMessage,
+} from "../record-bridge";
+
+const message: RecordStepMessage = {
+  type: RECORD_STEP,
+  requestId: "rec-1",
+  producerId: "document-1",
+  sequence: 1,
+  step: { op: "click", target: { tag: "button", name: "Submit" } },
+};
+
+describe("record step delivery protocol", () => {
+  it("requires a producer and a positive integer sequence", () => {
+    expect(isRecordStepMessage(message)).toBe(true);
+    expect(isRecordStepMessage({ ...message, producerId: "" })).toBe(false);
+    expect(isRecordStepMessage({ ...message, sequence: 0 })).toBe(false);
+    expect(isRecordStepMessage({ ...message, sequence: 1.5 })).toBe(false);
+  });
+
+  it("accepts only the acknowledgement for the sent sequence", () => {
+    expect(isAcceptedRecordStepAck({ ok: true, sequence: 2 }, 2)).toBe(true);
+    expect(isAcceptedRecordStepAck({ ok: true, sequence: 1 }, 2)).toBe(false);
+    expect(isAcceptedRecordStepAck({ ok: false, expectedSequence: 2, error: "gap" }, 2)).toBe(
+      false,
+    );
+  });
+});
@@ -0,0 +1,213 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { RECORD_FRAME_PORT, RECORD_FRAME_QUERY } from "../recording/frame-bridge";
+import { RecordFrameCoordinator } from "../recording/frame-coordinator";
+
+class ListenerSet<T extends (...args: never[]) => unknown> {
+  readonly listeners = new Set<T>();
+  addListener = (listener: T) => this.listeners.add(listener);
+  removeListener = (listener: T) => this.listeners.delete(listener);
+}
+
+function fakePort(sender: chrome.runtime.MessageSender) {
+  const messages: unknown[] = [];
+  const onMessage = new ListenerSet<(message: unknown) => void>();
+  const onDisconnect = new ListenerSet<() => void>();
+  return {
+    port: {
+      name: RECORD_FRAME_PORT,
+      sender,
+      onMessage,
+      onDisconnect,
+      postMessage: vi.fn((message: unknown) => messages.push(message)),
+      disconnect: vi.fn(),
+    } as unknown as chrome.runtime.Port,
+    messages,
+    receive(message: unknown) {
+      for (const listener of onMessage.listeners) listener(message);
+    },
+  };
+}
+
+describe("RecordFrameCoordinator", () => {
+  const onConnect = new ListenerSet<(port: chrome.runtime.Port) => void>();
+  const onMessage = new ListenerSet<
+    (
+      message: unknown,
+      sender: chrome.runtime.MessageSender,
+      sendResponse: (response: unknown) => void,
+    ) => boolean
+  >();
+
+  beforeEach(() => {
+    onConnect.listeners.clear();
+    onMessage.listeners.clear();
+    vi.stubGlobal("chrome", {
+      runtime: { onConnect, onMessage },
+    });
+  });
+
+  it("answers child-document queries for the initial tab before it is armed", () => {
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [],
+      sendToDocument: async () => ({ ok: true }),
+    });
+    coordinator.attach();
+    coordinator.begin("rec-1", 10, 3);
+
+    const query = (tabId: number) => {
+      let response: unknown;
+      for (const listener of onMessage.listeners) {
+        listener(
+          { type: RECORD_FRAME_QUERY },
+          {
+            tab: { id: tabId },
+            frameId: 7,
+            documentId: "child-document",
+          } as chrome.runtime.MessageSender,
+          (value) => {
+            response = value;
+          },
+        );
+      }
+      return response;
+    };
+
+    expect(query(3)).toEqual({ active: true, requestId: "rec-1", startedAtMs: 10 });
+    expect(query(4)).toEqual({ active: false });
+  });
+
+  it("starts a child Document that appears after the initial frame snapshot", async () => {
+    let notifyFrameNavigation:
+      | ((frame: {
+          tabId: number;
+          frameId: number;
+          documentId?: string;
+          lifecycle: "committed" | "completed";
+        }) => void)
+      | undefined;
+    const sendToDocument = vi.fn(async () => ({ ok: true }));
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [{ frameId: 0, documentId: "top-document" }],
+      sendToDocument,
+      subscribeFrameNavigation(listener) {
+        notifyFrameNavigation = listener;
+        return () => {};
+      },
+    });
+    coordinator.attach();
+    const onDocumentReady = vi.fn();
+    coordinator.begin("rec-1", 10, 3, onDocumentReady);
+    await coordinator.armTab("rec-1", 3);
+    sendToDocument.mockClear();
+
+    notifyFrameNavigation?.({
+      tabId: 3,
+      frameId: 7,
+      documentId: "late-child",
+      lifecycle: "completed",
+    });
+    await vi.waitFor(() => {
+      expect(sendToDocument).toHaveBeenCalledWith(
+        3,
+        { type: "bsk-record-frame-start", requestId: "rec-1", startedAtMs: 10 },
+        { documentId: "late-child" },
+      );
+    });
+    expect(onDocumentReady).not.toHaveBeenCalled();
+
+    const child = fakePort({
+      tab: { id: 3 },
+      frameId: 7,
+      documentId: "late-child",
+    } as chrome.runtime.MessageSender);
+    for (const listener of onConnect.listeners) listener(child.port);
+    child.receive({ type: "ready", requestId: "rec-1", producerId: "producer-1" });
+    notifyFrameNavigation?.({
+      tabId: 3,
+      frameId: 7,
+      documentId: "late-child",
+      lifecycle: "completed",
+    });
+    await vi.waitFor(() => {
+      expect(onDocumentReady).toHaveBeenCalledWith({
+        tabId: 3,
+        documentId: "late-child",
+        browserFrameId: 7,
+        producerId: "producer-1",
+      });
+    });
+  });
+
+  it("binds a producer to its sender Document and keeps final steps valid while stopping", async () => {
+    const sendToDocument = vi.fn(async () => ({ ok: true }));
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [
+        { frameId: 0, documentId: "top-document" },
+        { frameId: 7, documentId: "child-document" },
+      ],
+      sendToDocument,
+    });
+    coordinator.attach();
+    coordinator.begin("rec-1", 10, 3);
+    await expect(coordinator.armTab("rec-1", 3)).resolves.toBe(true);
+
+    const sender = {
+      tab: { id: 3 },
+      frameId: 7,
+      documentId: "child-document",
+    } as chrome.runtime.MessageSender;
+    const frame = fakePort(sender);
+    for (const listener of onConnect.listeners) listener(frame.port);
+    frame.receive({ type: "ready", requestId: "rec-1", producerId: "producer-1" });
+
+    expect(coordinator.sourceFor("rec-1", "producer-1", sender)).toEqual({
+      tabId: 3,
+      documentId: "child-document",
+      browserFrameId: 7,
+      producerId: "producer-1",
+    });
+
+    const stopping = coordinator.stop("rec-1");
+    expect(coordinator.sourceFor("rec-1", "producer-1", sender)).not.toBeNull();
+    const stop = frame.messages.find(
+      (message): message is { type: "stop"; commandId: string } =>
+        typeof message === "object" &&
+        message !== null &&
+        (message as { type?: string }).type === "stop",
+    );
+    expect(stop).toBeDefined();
+    frame.receive({
+      type: "stopped",
+      requestId: "rec-1",
+      commandId: stop!.commandId,
+      ok: true,
+    });
+    await expect(stopping).resolves.toBe(true);
+    expect(coordinator.sourceFor("rec-1", "producer-1", sender)).toBeNull();
+  });
+
+  it("rejects a producer used from another Document", async () => {
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [{ frameId: 0, documentId: "top-document" }],
+      sendToDocument: async () => ({ ok: true }),
+    });
+    coordinator.attach();
+    coordinator.begin("rec-1", 10, 3);
+    await coordinator.armTab("rec-1", 3);
+    const sender = {
+      tab: { id: 3 },
+      frameId: 0,
+      documentId: "top-document",
+    } as chrome.runtime.MessageSender;
+    const frame = fakePort(sender);
+    for (const listener of onConnect.listeners) listener(frame.port);
+    frame.receive({ type: "ready", requestId: "rec-1", producerId: "producer-1" });
+
+    expect(
+      coordinator.sourceFor("rec-1", "producer-1", {
+        ...sender,
+        documentId: "other-document",
+      }),
+    ).toBeNull();
+  });
+});
@@ -0,0 +1,70 @@
+import { describe, expect, it } from "vitest";
+import {
+  RECORD_DOCUMENT_ATTRIBUTE,
+  recordingDocumentMarkerValue,
+} from "@/shared/recording-document-identity";
+import { markRecordingDocument } from "../recording/document-marker";
+import { ObservationNodeIndex } from "../recording/observation-capture";
+
+describe("recording document marker", () => {
+  it("rejects a non-random Document identity", () => {
+    expect(() => markRecordingDocument("user@example.com")).toThrow(
+      "recording Document identity must be a random UUID",
+    );
+  });
+
+  it("restores the Document attribute exactly", () => {
+    document.documentElement.setAttribute(RECORD_DOCUMENT_ATTRIBUTE, "page-value");
+    const producerId = "123e4567-e89b-42d3-a456-426614174000";
+    const marker = markRecordingDocument(producerId);
+
+    expect(document.documentElement.getAttribute(RECORD_DOCUMENT_ATTRIBUTE)).toBe(
+      recordingDocumentMarkerValue(producerId),
+    );
+    marker.restore();
+    expect(document.documentElement.getAttribute(RECORD_DOCUMENT_ATTRIBUTE)).toBe("page-value");
+    document.documentElement.removeAttribute(RECORD_DOCUMENT_ATTRIBUTE);
+  });
+
+  it("indexes the CDP scope from the safe frame identity", () => {
+    const index = new ObservationNodeIndex({
+      rootFrameId: "root",
+      frames: [
+        {
+          frameId: "child",
+          target: { tabId: 3, sessionId: "oopif-session" },
+          recordingDocumentId: "producer-1",
+        },
+      ],
+      matchNodes: [],
+      refs: [],
+    });
+
+    expect(index.documentScope("producer-1")).toEqual({
+      frameId: "child",
+      target: { tabId: 3, sessionId: "oopif-session" },
+    });
+  });
+
+  it("fails closed when a recording identity maps to multiple Documents", () => {
+    const index = new ObservationNodeIndex({
+      rootFrameId: "root",
+      frames: [
+        {
+          frameId: "left",
+          target: { tabId: 3, sessionId: "left-session" },
+          recordingDocumentId: "duplicate",
+        },
+        {
+          frameId: "right",
+          target: { tabId: 3, sessionId: "right-session" },
+          recordingDocumentId: "duplicate",
+        },
+      ],
+      matchNodes: [],
+      refs: [],
+    });
+
+    expect(index.documentScope("duplicate")).toBeUndefined();
+  });
+});
@@ -0,0 +1,146 @@
+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,
+    vomText: '@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 finalizedFillTrace(value: string, redactValues: boolean) {
+  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",
+    redactValues,
+  });
+}
+
+function finalizedFillBody(value: string, redactValues: boolean): string {
+  return finalizedFillTrace(value, redactValues).states[0]!.body;
+}
+
+describe("record observation annotations", () => {
+  it("omits a fill literal when values are redacted", () => {
+    const secret = "hunter2-private";
+    const dumped = JSON.stringify(finalizedFillTrace(secret, true));
+    expect(dumped).toContain("step 1: fill");
+    expect(dumped).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",
+      vomText: "@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, vomText: "same" }).id).toBe("s1");
+    expect(first.register({ url: URL, vomText: "same" }).id).toBe("s1");
+    expect(second.register({ url: URL, vomText: "other" }).id).toBe("s1");
+  });
+
+  it("enriches metadata when a deduplicated observation becomes more complete", () => {
+    const registry = new RecordingStateRegistry();
+    registry.register({ url: URL, vomText: "same" });
+    const state = registry.register({
+      url: URL,
+      title: "Login",
+      vomText: "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,
+    });
+  });
+});
@@ -0,0 +1,289 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+
+const captureRecordingObservation = vi.hoisted(() => vi.fn());
+const waitForDocumentSettled = vi.hoisted(() => vi.fn(async () => "quiet" as const));
+
+vi.mock("../recording/observation-capture", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../recording/observation-capture")>();
+  return { ...actual, captureRecordingObservation };
+});
+
+vi.mock("../recording/document-settle", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../recording/document-settle")>();
+  return { ...actual, waitForDocumentSettled };
+});
+
+import { ObservationNodeIndex } from "../recording/observation-capture";
+import { RecordingObservationRuntime } from "../recording/recording-runtime";
+import type { RecordingDraftStep } from "../recording/types";
+
+function observation(url = "https://example.com/") {
+  return {
+    rootFrameId: "root",
+    index: new ObservationNodeIndex({ rootFrameId: "root", matchNodes: [], refs: [] }),
+    url,
+    title: "Example",
+    vomText: '@vom 1\nRootWebArea "Example"',
+    truncated: false,
+  };
+}
+
+function runtime(): RecordingObservationRuntime {
+  return new RecordingObservationRuntime({
+    cdp: { send: vi.fn() as unknown as CdpRunner["send"] },
+    tabsApi: { get: vi.fn(), query: vi.fn() } as unknown as ChromeTabsApi,
+  });
+}
+
+describe("RecordingObservationRuntime", () => {
+  afterEach(() => {
+    captureRecordingObservation.mockReset();
+    waitForDocumentSettled.mockClear();
+  });
+
+  it("shares one initial capture and includes it in flush", async () => {
+    let release!: (value: ReturnType<typeof observation>) => void;
+    captureRecordingObservation.mockReturnValueOnce(
+      new Promise((resolve) => {
+        release = resolve;
+      }),
+    );
+    const recording = runtime();
+
+    const first = recording.captureInitial(7);
+    const second = recording.captureInitial(7);
+    const flushed = recording.flush();
+    let flushCompleted = false;
+    void flushed.then(() => {
+      flushCompleted = true;
+    });
+
+    await Promise.resolve();
+    expect(captureRecordingObservation).toHaveBeenCalledTimes(1);
+    expect(flushCompleted).toBe(false);
+
+    release(observation());
+    await Promise.all([first, second, flushed]);
+    expect(flushCompleted).toBe(true);
+  });
+
+  it("cancels an in-flight initial capture", async () => {
+    captureRecordingObservation.mockImplementationOnce(
+      (input: { signal?: AbortSignal }) =>
+        new Promise((_, reject) => {
+          input.signal?.addEventListener(
+            "abort",
+            () => reject(new DOMException("observation aborted", "AbortError")),
+            { once: true },
+          );
+        }),
+    );
+    const recording = runtime();
+
+    const pending = recording.captureInitial(7);
+    recording.cancel();
+
+    await expect(pending).rejects.toMatchObject({ name: "AbortError" });
+  });
+
+  it("retries a failed initial capture when the recording settles at stop", async () => {
+    captureRecordingObservation
+      .mockRejectedValueOnce(new Error("document swapped"))
+      .mockResolvedValueOnce(observation());
+    const recording = runtime();
+
+    await expect(recording.captureInitial(7)).rejects.toThrow("document swapped");
+    await recording.settleTrailing(7, []);
+    const trace = recording.buildTrace({
+      drafts: [],
+      startedAt: "2026-08-19T00:00:00.000Z",
+      stoppedBy: "user_finish",
+      bskVersion: "0.1.6",
+    });
+
+    expect(captureRecordingObservation).toHaveBeenCalledTimes(2);
+    expect(trace.states).toHaveLength(1);
+  });
+
+  it("keeps runtime matching data out of the serialized trace", async () => {
+    const captured = observation();
+    captured.index = new ObservationNodeIndex({
+      rootFrameId: "root",
+      matchNodes: [
+        {
+          frameId: "root",
+          backendNodeId: 42,
+          tag: "button",
+          rect: { x: 10, y: 20, w: 100, h: 30 },
+          localRect: { x: 10, y: 20, w: 100, h: 30 },
+        },
+      ],
+      refs: [{ ref: "e1", backendNodeId: 42, role: "button", name: "Submit", line: 1 }],
+    });
+    captureRecordingObservation.mockResolvedValueOnce(captured);
+    const recording = runtime();
+
+    await recording.captureInitial(7);
+    const dumped = JSON.stringify(
+      recording.buildTrace({
+        drafts: [],
+        startedAt: "2026-08-19T00:00:00.000Z",
+        stoppedBy: "user_finish",
+        bskVersion: "0.1.6",
+      }),
+    );
+
+    expect(dumped).toContain("RootWebArea");
+    expect(dumped).not.toContain("matchNodes");
+    expect(dumped).not.toContain("localRect");
+    expect(dumped).not.toContain("backendNodeId");
+    expect(dumped).not.toContain("ObservationNodeIndex");
+  });
+
+  it("captures a tab transition without sharing observation cursors", async () => {
+    captureRecordingObservation
+      .mockResolvedValueOnce(observation("https://example.com/first"))
+      .mockResolvedValueOnce(observation("https://example.com/second"));
+    const recording = runtime();
+
+    await recording.captureInitial(4);
+    const transition = await recording.captureTabTransition(4, 5);
+    await recording.captureInitial(4);
+    await recording.captureInitial(5);
+
+    expect(transition).toEqual({
+      preStateId: "s1",
+      postStateId: "s2",
+      targetUrl: "https://example.com/second",
+    });
+    expect(captureRecordingObservation.mock.calls.map(([input]) => input.tabId)).toEqual([4, 5]);
+  });
+
+  it("binds an iframe draft to its marked CDP Document scope", async () => {
+    captureRecordingObservation.mockResolvedValueOnce({
+      ...observation(),
+      index: new ObservationNodeIndex({
+        rootFrameId: "root",
+        frames: [
+          {
+            frameId: "child",
+            target: { tabId: 7, sessionId: "oopif-session" },
+            recordingDocumentId: "producer-1",
+          },
+        ],
+        matchNodes: [
+          {
+            backendNodeId: 42,
+            frameId: "child",
+            tag: "button",
+            rect: { x: 410, y: 20, w: 100, h: 30 },
+            localRect: { x: 10, y: 20, w: 100, h: 30 },
+          },
+        ],
+        refs: [{ ref: "e1", backendNodeId: 42, frameId: "child", line: 1 }],
+      }),
+    });
+    const recording = runtime();
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "click" as const,
+        captureTarget: { tag: "button", role: "button", name: "Save" },
+        targetHint: {
+          geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+        },
+      },
+    ];
+
+    await recording.captureInitial(7);
+    await recording.processDraft(7, drafts, 0, "producer-1");
+    recording.cancel();
+
+    const draft = drafts[0];
+    expect(draft?.op).toBe("click");
+    if (!draft || draft.op !== "click") throw new Error("expected click draft");
+    expect(draft.targetHint).toMatchObject({
+      frameId: "child",
+      geometrySpace: "local",
+    });
+    expect(draft.matchedTarget?.ref).toBe("e1");
+  });
+
+  it("refreshes a late iframe before matching its first action", async () => {
+    const iframeObservation = {
+      ...observation(),
+      index: new ObservationNodeIndex({
+        rootFrameId: "root",
+        frames: [
+          {
+            frameId: "child",
+            target: { tabId: 7, sessionId: "oopif-session" },
+            recordingDocumentId: "producer-1",
+          },
+        ],
+        matchNodes: [
+          {
+            backendNodeId: 42,
+            frameId: "child",
+            tag: "button",
+            rect: { x: 410, y: 20, w: 100, h: 30 },
+            localRect: { x: 10, y: 20, w: 100, h: 30 },
+          },
+        ],
+        refs: [
+          {
+            ref: "e1",
+            backendNodeId: 42,
+            frameId: "child",
+            role: "button",
+            name: "表格视图",
+            line: 1,
+          },
+        ],
+      }),
+    };
+    captureRecordingObservation
+      .mockResolvedValueOnce(observation())
+      .mockResolvedValueOnce(iframeObservation)
+      .mockResolvedValueOnce(iframeObservation);
+    const recording = runtime();
+
+    await recording.captureInitial(7);
+    await recording.refreshDocument(7, "producer-1");
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "click",
+        captureTarget: { tag: "button", role: "button", name: "表格视图" },
+        targetHint: {
+          geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+        },
+      },
+    ];
+    await recording.processDraft(7, drafts, 0, "producer-1");
+    recording.cancel();
+
+    expect(captureRecordingObservation).toHaveBeenCalledTimes(3);
+    expect(waitForDocumentSettled).toHaveBeenCalledWith(
+      expect.anything(),
+      { frameId: "child", target: { tabId: 7, sessionId: "oopif-session" } },
+      { signal: expect.any(AbortSignal) },
+    );
+    const draft = drafts[0];
+    expect(draft?.op).toBe("click");
+    if (!draft || draft.op !== "click") throw new Error("expected click draft");
+    expect(draft.matchedTarget).toMatchObject({ ref: "e1", name: "表格视图" });
+  });
+
+  it("does not poison final flush when a frame readiness refresh fails", async () => {
+    captureRecordingObservation
+      .mockResolvedValueOnce(observation())
+      .mockRejectedValueOnce(new Error("child Document replaced"));
+    const recording = runtime();
+
+    await recording.captureInitial(7);
+    await expect(recording.refreshDocument(7, "producer-1")).rejects.toThrow(
+      "child Document replaced",
+    );
+    await expect(recording.flush()).resolves.toBeUndefined();
+  });
+});
@@ -1,80 +0,0 @@
-import { describe, expect, it } from "vitest";
-import { appendRecordedPayload, observeRecordedNavigation } from "../recording-step-buffer";
-
-describe("recording-step-buffer", () => {
-  it("stores semantic click without summary", () => {
-    const buffer = { steps: [], pendingNavigation: false };
-    appendRecordedPayload(buffer, {
-      op: "click",
-      target: { tag: "button", role: "button", name: "发布" },
-      expects_navigation: true,
-    });
-    expect(buffer.steps).toEqual([
-      {
-        op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
-      },
-    ]);
-    expect(buffer.pendingNavigation).toBe(true);
-  });
-
-  it("annotates navigated_to on action-caused navigation instead of wait_for_navigation", () => {
-    const buffer = {
-      steps: [
-        {
-          op: "click" as const,
-          target: { tag: "button", role: "button", name: "发布" },
-        },
-      ],
-      currentUrl: "https://example.com/a",
-      pendingNavigation: true,
-      pendingNavigationDeadline: Date.now() + 5_000,
-    };
-    observeRecordedNavigation(buffer, "https://example.com/b", true);
-    expect(buffer.steps).toEqual([
-      {
-        op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
-        navigated_to: "https://example.com/b",
-      },
-    ]);
-    expect(JSON.stringify(buffer.steps)).not.toContain("wait_for_navigation");
-  });
-
-  it("annotates navigated_to onto a select that auto-submits a navigation", () => {
-    const buffer = {
-      steps: [
-        {
-          op: "select" as const,
-          target: { tag: "select", role: "combobox", name: "分类" },
-          values: ["tech"],
-        },
-      ],
-      currentUrl: "https://example.com/list",
-      pendingNavigation: true,
-      pendingNavigationDeadline: Date.now() + 5_000,
-    };
-    observeRecordedNavigation(buffer, "https://example.com/list?cat=tech", true);
-    expect(buffer.steps).toEqual([
-      {
-        op: "select",
-        target: { tag: "select", role: "combobox", name: "分类" },
-        values: ["tech"],
-        navigated_to: "https://example.com/list?cat=tech",
-      },
-    ]);
-  });
-
-  it("emits navigate for uncaused URL changes", () => {
-    const buffer = {
-      steps: [],
-      currentUrl: "https://example.com/a",
-      pendingNavigation: false,
-    };
-    observeRecordedNavigation(buffer, "https://example.com/b", false);
-    expect(buffer.steps[0]).toMatchObject({
-      op: "navigate",
-      url: "https://example.com/b",
-    });
-  });
-});
@@ -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");
+  });
+});
@@ -0,0 +1,164 @@
+import { describe, expect, it } from "vitest";
+import { appendRecordedPayload, observeRecordedNavigation } from "../recording/step-buffer";
+
+describe("recording-step-buffer", () => {
+  it("stores semantic click without summary", () => {
+    const buffer = { steps: [], navigation: { pendingNavigation: false } };
+    appendRecordedPayload(buffer, {
+      op: "click",
+      target: { tag: "button", role: "button", name: "发布" },
+      expects_navigation: true,
+    });
+    expect(buffer.steps).toEqual([
+      {
+        op: "click",
+        captureTarget: { tag: "button", role: "button", name: "发布" },
+      },
+    ]);
+    expect(buffer.navigation.pendingNavigation).toBe(true);
+  });
+
+  it("keeps the hovered element description as a capture fallback", () => {
+    const buffer = { steps: [], navigation: { pendingNavigation: false } };
+    appendRecordedPayload(
+      buffer,
+      {
+        op: "hover",
+        target: { tag: "button", role: "button", name: "新建" },
+        geometry: {
+          rect: { x: 900, y: 8, w: 60, h: 32 },
+          tag: "button",
+        },
+      },
+      {
+        geometry: {
+          rect: { x: 900, y: 8, w: 60, h: 32 },
+          tag: "button",
+        },
+      },
+    );
+    expect(buffer.steps).toEqual([
+      {
+        op: "hover",
+        captureTarget: { tag: "button", role: "button", name: "新建" },
+        targetHint: {
+          geometry: {
+            rect: { x: 900, y: 8, w: 60, h: 32 },
+            tag: "button",
+          },
+        },
+      },
+    ]);
+  });
+
+  it("annotates navigated_to on action-caused navigation instead of wait_for_navigation", () => {
+    const buffer = {
+      steps: [
+        {
+          op: "click" as const,
+          captureTarget: { tag: "button", role: "button", name: "发布" },
+        },
+      ],
+      navigation: {
+        currentUrl: "https://example.com/a",
+        pendingNavigation: true,
+        pendingNavigationDeadline: Date.now() + 5_000,
+      },
+    };
+    observeRecordedNavigation(buffer, "https://example.com/b", true);
+    expect(buffer.steps).toEqual([
+      {
+        op: "click",
+        captureTarget: { tag: "button", role: "button", name: "发布" },
+        navigatedTo: "https://example.com/b",
+      },
+    ]);
+    expect(JSON.stringify(buffer.steps)).not.toContain("wait_for_navigation");
+  });
+
+  it("annotates navigated_to onto a select that auto-submits a navigation", () => {
+    const buffer = {
+      steps: [
+        {
+          op: "select" as const,
+          captureTarget: { tag: "select", role: "combobox", name: "分类" },
+          values: ["tech"],
+        },
+      ],
+      navigation: {
+        currentUrl: "https://example.com/list",
+        pendingNavigation: true,
+        pendingNavigationDeadline: Date.now() + 5_000,
+      },
+    };
+    observeRecordedNavigation(buffer, "https://example.com/list?cat=tech", true);
+    expect(buffer.steps).toEqual([
+      {
+        op: "select",
+        captureTarget: { tag: "select", role: "combobox", name: "分类" },
+        values: ["tech"],
+        navigatedTo: "https://example.com/list?cat=tech",
+      },
+    ]);
+  });
+
+  it("emits navigate for uncaused URL changes", () => {
+    const buffer = {
+      steps: [],
+      navigation: { currentUrl: "https://example.com/a", pendingNavigation: false },
+    };
+    const result = observeRecordedNavigation(buffer, "https://example.com/b", false);
+    expect(result).toEqual({ kind: "appended", index: 0 });
+    expect(buffer.steps[0]).toMatchObject({
+      op: "navigate",
+      url: "https://example.com/b",
+    });
+  });
+
+  it("asks the recorder to coalesce redirect hops instead of emitting each one", () => {
+    const buffer = {
+      steps: [],
+      navigation: {
+        currentUrl: "https://passport.example/login",
+        pendingNavigation: false,
+      },
+    };
+    const hop1 = observeRecordedNavigation(
+      buffer,
+      "https://passport.example/callback",
+      false,
+      "link",
+      ["server_redirect"],
+    );
+    expect(hop1).toEqual({
+      kind: "coalesce_redirect",
+      url: "https://passport.example/callback",
+    });
+    expect(buffer.steps).toEqual([]);
+
+    const hop2 = observeRecordedNavigation(buffer, "https://app.example/dashboard", false, "link", [
+      "client_redirect",
+    ]);
+    expect(hop2).toEqual({
+      kind: "coalesce_redirect",
+      url: "https://app.example/dashboard",
+    });
+    expect(buffer.steps).toEqual([]);
+    expect(buffer.navigation.currentUrl).toBe("https://app.example/dashboard");
+  });
+
+  it("does not reuse redirect metadata for a later content-observed URL change", () => {
+    const buffer = {
+      steps: [],
+      navigation: {
+        currentUrl: "https://example.com/redirect",
+        pendingNavigation: false,
+      },
+    };
+
+    const result = observeRecordedNavigation(buffer, "https://example.com/spa");
+
+    expect(result).toEqual({ kind: "appended", index: 0 });
+    expect(buffer.steps[0]).toMatchObject({ op: "navigate", url: "https://example.com/spa" });
+  });
+});
@@ -0,0 +1,39 @@
+import { describe, expect, it } from "vitest";
+import { RecordingTabCoordinator } from "../recording/tab-coordinator";
+
+describe("RecordingTabCoordinator", () => {
+  it("keeps navigation state isolated per tab", () => {
+    const tabs = new RecordingTabCoordinator(4, "https://example.com/first");
+    const first = tabs.navigation(4);
+    first.pendingNavigation = true;
+    const second = tabs.navigation(5, "https://example.com/second");
+
+    expect(second).toEqual({
+      currentUrl: "https://example.com/second",
+      pendingNavigation: false,
+    });
+    expect(tabs.navigation(4)).toBe(first);
+    expect(tabs.navigation(4).pendingNavigation).toBe(true);
+  });
+
+  it("invalidates an earlier activation when a newer tab becomes active", () => {
+    const tabs = new RecordingTabCoordinator(4);
+    const second = tabs.noteActivation(5);
+    const third = tabs.noteActivation(6);
+
+    expect(tabs.isLatest(second)).toBe(false);
+    expect(tabs.isLatest(third)).toBe(true);
+    tabs.commit(6);
+    expect(tabs.currentTabId).toBe(6);
+  });
+
+  it("commits the freshly observed URL when returning to an existing tab", () => {
+    const tabs = new RecordingTabCoordinator(4);
+    tabs.navigation(5, "https://example.com/old");
+
+    tabs.commit(5, "https://example.com/new");
+
+    expect(tabs.currentTabId).toBe(5);
+    expect(tabs.navigation(5).currentUrl).toBe("https://example.com/new");
+  });
+});
@@ -0,0 +1,159 @@
+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("matches iframe capture geometry in the child viewport coordinate space", () => {
+    const child = node(42, "child", 410);
+    child.localRect = { x: 10, y: 20, w: 100, h: 30 };
+    const target = matchObservationTarget({
+      observation: observation(
+        [child],
+        [{ ref: "e1", backendNodeId: 42, frameId: "child", line: 1 }],
+      ),
+      hint: {
+        frameId: "child",
+        geometrySpace: "local",
+        geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+      },
+    });
+    expect(target.ref).toBe("e1");
+  });
+
+  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("fails closed when the source Document has no VOM frame mapping", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root")],
+        [{ ref: "e1", backendNodeId: 42, role: "button", name: "发布", line: 1 }],
+      ),
+      hint: {
+        frameId: null,
+        geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+      },
+      fallback: { tag: "button", role: "button", name: "发布" },
+    });
+    expect(target).toEqual({ role: "button", 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");
+  });
+});
@@ -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", () => {
@@ -18,36 +27,47 @@ describe("shouldRecordPress", () => {
 });

 describe("reduceTraceSteps", () => {
+  it("does not expose internal tab transitions in trace v2", () => {
+    const trace = reduceTraceSteps([
+      {
+        op: "switch_tab",
+        preStateId: "s1",
+        postStateId: "s2",
+      },
+    ]);
+    expect(trace.steps).toEqual([]);
+  });
+
  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 +129,9 @@ 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 +145,16 @@ 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",
@@ -151,36 +171,32 @@ describe("reduceTraceSteps", () => {
    });
  });

-  it("keeps hover steps before menu clicks", () => {
+  it("drops hover steps, which only exist in trace v3", () => {
    const { steps } = 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",
    );
-    expect(steps.map((s) => s.op)).toEqual(["hover", "click"]);
-    expect(steps[0]).toMatchObject({
-      op: "hover",
-      page: "p1",
-      target: { name: "Account" },
-    });
+    expect(steps.map((s) => s.op)).toEqual(["click"]);
  });

  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");
  });
 });
@@ -0,0 +1,132 @@
+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("removes form literals when value redaction is requested", () => {
+    const reduced = reduceTraceStepsV3(
+      [
+        {
+          op: "fill",
+          value: "private@example.com",
+          preStateId: "s1",
+          postStateId: "s1",
+        },
+        {
+          op: "select",
+          values: ["private-account-id"],
+          labels: ["Private account"],
+          preStateId: "s1",
+          postStateId: "s1",
+        },
+      ],
+      { redactValues: true },
+    );
+
+    expect(reduced.steps[0]).toMatchObject({ op: "fill", value: "***", redacted: true });
+    expect(reduced.steps[1]).toMatchObject({ op: "select" });
+    expect(reduced.steps[1]).not.toHaveProperty("selection");
+    expect(JSON.stringify(reduced.steps)).not.toContain("private@example.com");
+    expect(JSON.stringify(reduced.steps)).not.toContain("private-account-id");
+  });
+
+  it("emits tab transitions only for callers that advertised support", () => {
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "switch_tab",
+        preStateId: "s1",
+        postStateId: "s2",
+      },
+    ];
+
+    expect(reduceTraceStepsV3(drafts).steps).toEqual([]);
+    expect(reduceTraceStepsV3(drafts, { includeTabSwitches: true }).steps).toEqual([
+      { op: "switch_tab", id: 1, state: "s1", result: { state: "s2" } },
+    ]);
+  });
+
+  it("keeps hover steps before menu clicks", () => {
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "hover",
+        captureTarget: { tag: "span", role: "button", name: "Account" },
+        preStateId: "s1",
+        postStateId: "s1",
+      },
+      {
+        op: "click",
+        captureTarget: { tag: "a", role: "link", name: "Profile" },
+        preStateId: "s1",
+        postStateId: "s1",
+      },
+    ];
+
+    expect(reduceTraceStepsV3(drafts).steps.map((s) => s.op)).toEqual(["hover", "click"]);
+  });
+
+  it("does not export a tab transition without both observation endpoints", () => {
+    const sourceOnly: RecordingDraftStep = { op: "switch_tab", preStateId: "s1" };
+    const targetOnly: RecordingDraftStep = { op: "switch_tab", postStateId: "s2" };
+
+    expect(
+      reduceTraceStepsV3([sourceOnly, targetOnly], { includeTabSwitches: true }).steps,
+    ).toEqual([]);
+  });
+
+  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", vomText: "@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 },
+    });
+  });
+});
@@ -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;
@@ -1,7 +1,10 @@
+import { normalizeDaemonPort } from "@/transport/daemon-endpoint";
+
 const STORAGE_KEY = "bsk_instance_id";
 const LABEL_STORAGE_KEY = "bh_label";
 const CONNECTION_ENABLED_KEY = "bh_connection_enabled";
 const CONTROL_HINTS_HIDDEN_KEY = "bsk_control_hints_hidden";
+const DAEMON_PORT_KEY = "bsk_daemon_port";

 export interface StorageBackend {
  get(keys: string | string[]): Promise<Record<string, unknown>>;
@@ -127,9 +130,23 @@ export async function setControlHintsHidden(
  await storage.set({ [CONTROL_HINTS_HIDDEN_KEY]: hidden });
 }

+/** Defaults to {@link DEFAULT_DAEMON_PORT} when unset or invalid. */
+export async function getDaemonPort(storage: StorageBackend = defaultStorage()): Promise<number> {
+  const items = await storage.get(DAEMON_PORT_KEY);
+  return normalizeDaemonPort(items[DAEMON_PORT_KEY]);
+}
+
+export async function setDaemonPort(
+  port: number,
+  storage: StorageBackend = defaultStorage(),
+): Promise<void> {
+  await storage.set({ [DAEMON_PORT_KEY]: port });
+}
+
 export const STORAGE_KEYS = {
  INSTANCE_ID: STORAGE_KEY,
  LABEL: LABEL_STORAGE_KEY,
  CONNECTION_ENABLED: CONNECTION_ENABLED_KEY,
  CONTROL_HINTS_HIDDEN: CONTROL_HINTS_HIDDEN_KEY,
+  DAEMON_PORT: DAEMON_PORT_KEY,
 } as const;
@@ -5,19 +5,14 @@ import type { SnapshotInfo } from "./connection-controller";
 *  - Background pushes `{ kind: "snapshot", data: SnapshotInfo }`.
 *  - Popup sends `{ kind: "set_label" }`, `{ kind: "set_connection_enabled" }`, etc.
 *
- * NOTE(review M4/M5 C2): the `set_port` variant is defined as a
- * placeholder so the future custom-port UI does not have to re-design
- * the bridge, but the popup does NOT render a control that emits it
- * yet and the background does NOT route it. The wiring requires
- * ConnectionController to dispose its current Transport and persist
- * the port in chrome.storage; tracked as a follow-up.
+ * Daemon port preference is persisted via `chrome.storage.local` instead
+ * of this bridge (see `use-daemon-port.ts`).
 */

 export const POPUP_PORT_NAME = "popup";

 export type PopupOutbound =
  | { kind: "set_label"; value: string }
-  | { kind: "set_port"; value: number }
  | { kind: "set_connection_enabled"; value: boolean };

 export type PopupInbound = { kind: "snapshot"; data: SnapshotInfo };
@@ -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";
@@ -16,6 +16,10 @@ export interface RecordStartAck {
  ok: true;
 }

+export type RecordStepAck =
+  | { ok: true; sequence: number }
+  | { ok: false; expectedSequence: number; error: string };
+
 export type RecordStopAck = { ok: true } | { ok: false; error: string };

 export interface RecordQueryMessage {
@@ -42,7 +46,7 @@ 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">;
@@ -50,17 +54,30 @@ export interface RecordStepPayload {
  labels?: string[];
  url?: string;
  redacted?: boolean;
+  commit?: "enter" | "suggestion" | "blur";
  /** Page URL when the step was captured. */
  page_url?: string;
+  /** Event-target bounds in the source frame's viewport coordinate space. */
+  geometry?: {
+    rect: { x: number; y: number; w: number; h: number };
+    tag: string;
+  };
  /** Capture-only hint; never persisted unless converted to navigated_to. */
  expects_navigation?: boolean;
  /** Whether an observed URL change was synchronously caused by the action. */
  navigation_caused_by_action?: boolean;
+  /** Raw webNavigation transition metadata for cause mapping. */
+  transitionType?: string;
+  transitionQualifiers?: string[];
 }

 export interface RecordStepMessage {
  type: typeof RECORD_STEP;
  requestId: string;
+  /** Stable for the lifetime of one content-script document. */
+  producerId: string;
+  /** Monotonic within one content-script producer and recording request. */
+  sequence: number;
  step: RecordStepPayload;
 }

@@ -112,8 +129,27 @@ export function isRecordQueryMessage(msg: unknown): msg is RecordQueryMessage {
 export function isRecordStepMessage(msg: unknown): msg is RecordStepMessage {
  if (typeof msg !== "object" || msg === null) return false;
  const m = msg as Record<string, unknown>;
-  if (m.type !== RECORD_STEP || typeof m.requestId !== "string") return false;
+  if (
+    m.type !== RECORD_STEP ||
+    typeof m.requestId !== "string" ||
+    typeof m.producerId !== "string" ||
+    m.producerId.length === 0 ||
+    typeof m.sequence !== "number" ||
+    !Number.isSafeInteger(m.sequence) ||
+    m.sequence < 1
+  ) {
+    return false;
+  }
  const step = m.step;
  if (typeof step !== "object" || step === null) return false;
  return typeof (step as RecordStepPayload).op === "string";
 }
+
+export function isAcceptedRecordStepAck(
+  value: unknown,
+  sequence: number,
+): value is Extract<RecordStepAck, { ok: true }> {
+  if (typeof value !== "object" || value === null) return false;
+  const ack = value as Partial<RecordStepAck>;
+  return ack.ok === true && ack.sequence === sequence;
+}
@@ -1,136 +0,0 @@
-import type { DraftTraceStep } from "@/transport/types";
-import type { RecordStepPayload } from "./record-bridge";
-
-export interface RecordingStepBuffer {
-  steps: DraftTraceStep[];
-  currentUrl?: string;
-  pendingNavigation: boolean;
-  pendingNavigationDeadline?: number;
-}
-
-const NAVIGATION_TRIGGER_WINDOW_MS = 3_000;
-
-function toDraftStep(payload: RecordStepPayload): DraftTraceStep | null {
-  const pageUrl = payload.page_url;
-  switch (payload.op) {
-    case "click":
-      return payload.target
-        ? {
-            op: "click",
-            target: payload.target,
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "hover":
-      return payload.target
-        ? {
-            op: "hover",
-            target: payload.target,
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "fill":
-      return payload.target
-        ? {
-            op: "fill",
-            target: payload.target,
-            value: payload.value ?? "",
-            ...(payload.redacted ? { redacted: true } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "press":
-      return payload.key
-        ? {
-            op: "press",
-            key: payload.key,
-            ...(payload.target ? { target: payload.target } : {}),
-            ...(payload.modifiers?.length ? { modifiers: payload.modifiers } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "select":
-      return payload.target && payload.values
-        ? {
-            op: "select",
-            target: payload.target,
-            values: payload.values,
-            ...(payload.labels?.length ? { labels: payload.labels } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "navigate":
-      return null;
-  }
-}
-
-function annotateLastStepNavigation(buffer: RecordingStepBuffer, url: string): boolean {
-  for (let i = buffer.steps.length - 1; i >= 0; i -= 1) {
-    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 };
-      return true;
-    }
-    break;
-  }
-  return false;
-}
-
-export function observeRecordedNavigation(
-  buffer: RecordingStepBuffer,
-  url: string,
-  causedByAction?: boolean,
-): void {
-  if (!url || url === buffer.currentUrl) return;
-  buffer.currentUrl = url;
-  const pendingIsCurrent =
-    buffer.pendingNavigation &&
-    (buffer.pendingNavigationDeadline === undefined ||
-      buffer.pendingNavigationDeadline >= Date.now());
-
-  if (causedByAction === true || (causedByAction === undefined && pendingIsCurrent)) {
-    buffer.pendingNavigation = false;
-    buffer.pendingNavigationDeadline = undefined;
-    if (!annotateLastStepNavigation(buffer, url)) {
-      buffer.steps.push({
-        op: "navigate",
-        url,
-        page_url: url,
-      });
-    }
-    return;
-  }
-
-  buffer.pendingNavigation = false;
-  buffer.pendingNavigationDeadline = undefined;
-  buffer.steps.push({
-    op: "navigate",
-    url,
-    page_url: url,
-  });
-}
-
-export function appendRecordedPayload(
-  buffer: RecordingStepBuffer,
-  payload: RecordStepPayload,
-): void {
-  if (payload.op === "navigate") {
-    if (payload.url) {
-      observeRecordedNavigation(buffer, payload.url, payload.navigation_caused_by_action);
-    }
-    return;
-  }
-  const step = toDraftStep({
-    ...payload,
-    page_url: payload.page_url ?? buffer.currentUrl,
-  });
-  if (!step) return;
-  buffer.steps.push(step);
-  if (step.op === "click" || step.op === "press" || step.op === "select" || step.op === "fill") {
-    buffer.pendingNavigation = payload.expects_navigation === true;
-    buffer.pendingNavigationDeadline = buffer.pendingNavigation
-      ? Date.now() + NAVIGATION_TRIGGER_WINDOW_MS
-      : undefined;
-  }
-}
@@ -0,0 +1,39 @@
+import {
+  RECORD_DOCUMENT_ATTRIBUTE,
+  recordingDocumentMarkerValue,
+} from "@/shared/recording-document-identity";
+
+export interface RecordingDocumentMarker {
+  restore(): void;
+  ensure(): void;
+}
+
+export function waitForDocumentElement(): Promise<HTMLElement> {
+  if (document.documentElement) return Promise.resolve(document.documentElement);
+  return new Promise((resolve) => {
+    const observer = new MutationObserver(() => {
+      if (!document.documentElement) return;
+      observer.disconnect();
+      resolve(document.documentElement);
+    });
+    observer.observe(document, { childList: true });
+  });
+}
+
+export function markRecordingDocument(
+  producerId: string,
+  root: HTMLElement = document.documentElement,
+): RecordingDocumentMarker {
+  const previous = root.getAttribute(RECORD_DOCUMENT_ATTRIBUTE);
+  const markerValue = recordingDocumentMarkerValue(producerId);
+  const ensure = () => root.setAttribute(RECORD_DOCUMENT_ATTRIBUTE, markerValue);
+  ensure();
+  return {
+    ensure,
+    restore() {
+      if (root.getAttribute(RECORD_DOCUMENT_ATTRIBUTE) !== markerValue) return;
+      if (previous === null) root.removeAttribute(RECORD_DOCUMENT_ATTRIBUTE);
+      else root.setAttribute(RECORD_DOCUMENT_ATTRIBUTE, previous);
+    },
+  };
+}
@@ -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";
+  }
+}
@@ -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";
+}
@@ -0,0 +1,65 @@
+export const RECORD_FRAME_PORT = "bsk-record-frame";
+export const RECORD_FRAME_QUERY = "bsk-record-frame-query";
+export const RECORD_FRAME_START = "bsk-record-frame-start";
+
+export interface RecordFrameQueryMessage {
+  type: typeof RECORD_FRAME_QUERY;
+}
+
+export interface RecordFrameQueryResponse {
+  active: boolean;
+  requestId?: string;
+  startedAtMs?: number;
+}
+
+export interface RecordFrameStartMessage {
+  type: typeof RECORD_FRAME_START;
+  requestId: string;
+  startedAtMs: number;
+}
+
+export type RecordFramePortMessage =
+  | {
+      type: "ready";
+      requestId: string;
+      producerId: string;
+    }
+  | {
+      type: "ready_ack";
+      requestId: string;
+      producerId: string;
+    }
+  | {
+      type: "stop";
+      requestId: string;
+      commandId: string;
+    }
+  | {
+      type: "cancel";
+      requestId: string;
+    }
+  | {
+      type: "stopped";
+      requestId: string;
+      commandId: string;
+      ok: boolean;
+      error?: string;
+    };
+
+export function isRecordFrameQueryMessage(value: unknown): value is RecordFrameQueryMessage {
+  return (
+    typeof value === "object" &&
+    value !== null &&
+    (value as { type?: unknown }).type === RECORD_FRAME_QUERY
+  );
+}
+
+export function isRecordFrameStartMessage(value: unknown): value is RecordFrameStartMessage {
+  if (typeof value !== "object" || value === null) return false;
+  const message = value as Partial<RecordFrameStartMessage>;
+  return (
+    message.type === RECORD_FRAME_START &&
+    typeof message.requestId === "string" &&
+    typeof message.startedAtMs === "number"
+  );
+}
@@ -0,0 +1,399 @@
+import {
+  isRecordFrameQueryMessage,
+  RECORD_FRAME_PORT,
+  RECORD_FRAME_START,
+  type RecordFramePortMessage,
+  type RecordFrameQueryResponse,
+  type RecordFrameStartMessage,
+} from "./frame-bridge";
+
+export interface RecordingCaptureScope {
+  tabId: number;
+  documentId: string;
+  browserFrameId: number;
+  producerId: string;
+}
+
+interface ArmedRecording {
+  requestId: string;
+  startedAtMs: number;
+  tabIds: Set<number>;
+  agents: Map<string, FrameAgent>;
+  onDocumentReady?: (scope: RecordingCaptureScope) => void | Promise<void>;
+  finishing: boolean;
+}
+
+interface FrameAgent extends RecordingCaptureScope {
+  requestId: string;
+  port: chrome.runtime.Port;
+  stopWaiters: Map<string, (ok: boolean) => void>;
+}
+
+interface BrowserFrame {
+  frameId: number;
+  documentId?: string;
+}
+
+interface BrowserFrameNavigation extends BrowserFrame {
+  tabId: number;
+  lifecycle: "committed" | "completed";
+}
+
+const RECORD_FRAME_STOP_TIMEOUT_MS = 5_000;
+
+export interface RecordFrameCoordinatorDeps {
+  getAllFrames(tabId: number): Promise<BrowserFrame[]>;
+  sendToDocument(
+    tabId: number,
+    message: RecordFrameStartMessage,
+    target: { documentId?: string; frameId?: number },
+  ): Promise<unknown>;
+  subscribeFrameNavigation?(listener: (frame: BrowserFrameNavigation) => void): () => void;
+}
+
+function documentKey(tabId: number, documentId: string): string {
+  return `${tabId}:${documentId}`;
+}
+
+function senderAddress(
+  sender: chrome.runtime.MessageSender,
+): { tabId: number; documentId: string; browserFrameId: number } | null {
+  const tabId = sender.tab?.id;
+  const documentId = sender.documentId;
+  const browserFrameId = sender.frameId;
+  if (
+    typeof tabId !== "number" ||
+    typeof documentId !== "string" ||
+    typeof browserFrameId !== "number"
+  ) {
+    return null;
+  }
+  return { tabId, documentId, browserFrameId };
+}
+
+function defaultDeps(): RecordFrameCoordinatorDeps {
+  return {
+    async getAllFrames(tabId) {
+      return (await chrome.webNavigation.getAllFrames({ tabId })) ?? [];
+    },
+    sendToDocument(tabId, message, target) {
+      return chrome.tabs.sendMessage(tabId, message, target);
+    },
+    subscribeFrameNavigation(listener) {
+      const onCommitted = (details: chrome.webNavigation.WebNavigationTransitionCallbackDetails) =>
+        listener({ ...details, lifecycle: "committed" });
+      const onCompleted = (details: chrome.webNavigation.WebNavigationFramedCallbackDetails) =>
+        listener({ ...details, lifecycle: "completed" });
+      chrome.webNavigation.onCommitted.addListener(onCommitted);
+      chrome.webNavigation.onCompleted.addListener(onCompleted);
+      return () => {
+        chrome.webNavigation.onCommitted.removeListener(onCommitted);
+        chrome.webNavigation.onCompleted.removeListener(onCompleted);
+      };
+    },
+  };
+}
+
+export class RecordFrameCoordinator {
+  readonly #deps: RecordFrameCoordinatorDeps;
+  readonly #recordings = new Map<string, ArmedRecording>();
+  #attached = false;
+  #detachFrameNavigation: (() => void) | null = null;
+
+  constructor(deps: RecordFrameCoordinatorDeps = defaultDeps()) {
+    this.#deps = deps;
+  }
+
+  attach(): () => void {
+    if (this.#attached) return () => {};
+    this.#attached = true;
+    chrome.runtime.onConnect.addListener(this.#onConnect);
+    chrome.runtime.onMessage.addListener(this.#onMessage);
+    this.#detachFrameNavigation =
+      this.#deps.subscribeFrameNavigation?.(this.#onFrameNavigation) ?? null;
+    return () => {
+      if (!this.#attached) return;
+      this.#attached = false;
+      chrome.runtime.onConnect.removeListener(this.#onConnect);
+      chrome.runtime.onMessage.removeListener(this.#onMessage);
+      this.#detachFrameNavigation?.();
+      this.#detachFrameNavigation = null;
+      for (const recording of this.#recordings.values()) this.#cancelAgents(recording);
+      this.#recordings.clear();
+    };
+  }
+
+  begin(
+    requestId: string,
+    startedAtMs: number,
+    initialTabId: number,
+    onDocumentReady?: (scope: RecordingCaptureScope) => void | Promise<void>,
+  ): void {
+    const previous = this.#recordings.get(requestId);
+    if (previous) this.#cancelAgents(previous);
+    this.#recordings.set(requestId, {
+      requestId,
+      startedAtMs,
+      // Register the initial tab before navigation begins. A newly-created
+      // child document can query at document_start before armTab's frame
+      // snapshot sees it, especially when Chromium promotes it to an OOPIF.
+      tabIds: new Set([initialTabId]),
+      agents: new Map(),
+      ...(onDocumentReady ? { onDocumentReady } : {}),
+      finishing: false,
+    });
+  }
+
+  async armTab(requestId: string, tabId: number): Promise<boolean> {
+    const recording = this.#recordings.get(requestId);
+    if (!recording || recording.finishing) return false;
+    recording.tabIds.add(tabId);
+
+    let frames: BrowserFrame[];
+    try {
+      frames = await this.#deps.getAllFrames(tabId);
+    } catch {
+      frames = [{ frameId: 0 }];
+    }
+    if (!frames.some((frame) => frame.frameId === 0)) frames.unshift({ frameId: 0 });
+
+    const results = await Promise.all(
+      frames.map(async (frame) => {
+        const started = await this.#startFrame(recording, tabId, frame);
+        return { frameId: frame.frameId, started };
+      }),
+    );
+    return results.some((result) => result.frameId === 0 && result.started);
+  }
+
+  sourceFor(
+    requestId: string,
+    producerId: string,
+    sender: chrome.runtime.MessageSender,
+  ): RecordingCaptureScope | null {
+    const address = senderAddress(sender);
+    const recording = this.#recordings.get(requestId);
+    if (!address || !recording) return null;
+    const agent = recording.agents.get(documentKey(address.tabId, address.documentId));
+    if (!agent || agent.producerId !== producerId) return null;
+    return {
+      tabId: agent.tabId,
+      documentId: agent.documentId,
+      browserFrameId: agent.browserFrameId,
+      producerId: agent.producerId,
+    };
+  }
+
+  async stop(requestId: string): Promise<boolean> {
+    const recording = this.#recordings.get(requestId);
+    if (!recording) return true;
+    recording.finishing = true;
+    const commandId = crypto.randomUUID();
+    const results = await Promise.all(
+      [...recording.agents.values()].map((agent) => this.#stopAgent(agent, requestId, commandId)),
+    );
+    const succeeded = results.every(Boolean);
+    if (succeeded) this.#recordings.delete(requestId);
+    else recording.finishing = false;
+    return succeeded;
+  }
+
+  cancel(requestId: string): void {
+    const recording = this.#recordings.get(requestId);
+    if (!recording) return;
+    this.#cancelAgents(recording);
+    this.#recordings.delete(requestId);
+  }
+
+  readonly #onMessage = (
+    message: unknown,
+    sender: chrome.runtime.MessageSender,
+    sendResponse: (response: RecordFrameQueryResponse) => void,
+  ): boolean => {
+    if (!isRecordFrameQueryMessage(message)) return false;
+    const tabId = sender.tab?.id;
+    const recording =
+      typeof tabId === "number"
+        ? [...this.#recordings.values()].find(
+            (candidate) => !candidate.finishing && candidate.tabIds.has(tabId),
+          )
+        : undefined;
+    sendResponse(
+      recording
+        ? {
+            active: true,
+            requestId: recording.requestId,
+            startedAtMs: recording.startedAtMs,
+          }
+        : { active: false },
+    );
+    return false;
+  };
+
+  readonly #onFrameNavigation = (frame: BrowserFrameNavigation): void => {
+    if (frame.frameId === 0) return;
+    for (const recording of this.#recordings.values()) {
+      if (recording.finishing || !recording.tabIds.has(frame.tabId)) continue;
+      // onCommitted can race document_start, while onCompleted runs after the
+      // content script is available. Starting twice is safe and closes both
+      // the early-query and late-SPA-frame gaps.
+      void (async () => {
+        const started = await this.#startFrame(recording, frame.tabId, frame);
+        if (!started || frame.lifecycle !== "completed" || recording.finishing) return;
+        const agent = frame.documentId
+          ? recording.agents.get(documentKey(frame.tabId, frame.documentId))
+          : [...recording.agents.values()].find(
+              (candidate) =>
+                candidate.tabId === frame.tabId && candidate.browserFrameId === frame.frameId,
+            );
+        if (!agent) return;
+        await recording.onDocumentReady?.({
+          tabId: agent.tabId,
+          documentId: agent.documentId,
+          browserFrameId: agent.browserFrameId,
+          producerId: agent.producerId,
+        });
+      })();
+    }
+  };
+
+  readonly #onConnect = (port: chrome.runtime.Port): void => {
+    if (port.name !== RECORD_FRAME_PORT) return;
+    const address = senderAddress(port.sender ?? {});
+    if (!address) {
+      port.disconnect();
+      return;
+    }
+    let registered: FrameAgent | null = null;
+    port.onMessage.addListener((raw: unknown) => {
+      const message = raw as Partial<RecordFramePortMessage>;
+      if (message.type === "ready") {
+        if (typeof message.requestId !== "string" || typeof message.producerId !== "string") {
+          port.disconnect();
+          return;
+        }
+        const requestId = message.requestId;
+        const producerId = message.producerId;
+        if (registered) {
+          if (registered.requestId === requestId && registered.producerId === producerId) {
+            port.postMessage({
+              type: "ready_ack",
+              requestId,
+              producerId,
+            } satisfies RecordFramePortMessage);
+          } else {
+            port.disconnect();
+          }
+          return;
+        }
+        const recording = this.#recordings.get(requestId);
+        if (
+          !recording ||
+          recording.finishing ||
+          !recording.tabIds.has(address.tabId) ||
+          producerId.length === 0
+        ) {
+          port.disconnect();
+          return;
+        }
+        const agent: FrameAgent = {
+          ...address,
+          requestId,
+          producerId,
+          port,
+          stopWaiters: new Map(),
+        };
+        registered = agent;
+        const key = documentKey(address.tabId, address.documentId);
+        const previous = recording.agents.get(key);
+        if (previous && previous !== agent) previous.port.disconnect();
+        recording.agents.set(key, agent);
+        port.postMessage({
+          type: "ready_ack",
+          requestId,
+          producerId,
+        } satisfies RecordFramePortMessage);
+        return;
+      }
+      if (
+        message.type === "stopped" &&
+        registered &&
+        message.requestId === registered.requestId &&
+        typeof message.commandId === "string"
+      ) {
+        registered.stopWaiters.get(message.commandId)?.(message.ok === true);
+        registered.stopWaiters.delete(message.commandId);
+      }
+    });
+    port.onDisconnect.addListener(() => {
+      if (!registered) return;
+      for (const resolve of registered.stopWaiters.values()) resolve(true);
+      const recording = this.#recordings.get(registered.requestId);
+      const key = documentKey(registered.tabId, registered.documentId);
+      if (recording?.agents.get(key) === registered) recording.agents.delete(key);
+    });
+  };
+
+  #stopAgent(agent: FrameAgent, requestId: string, commandId: string): Promise<boolean> {
+    return new Promise((resolve) => {
+      const timer = setTimeout(() => {
+        agent.stopWaiters.delete(commandId);
+        resolve(false);
+      }, RECORD_FRAME_STOP_TIMEOUT_MS);
+      agent.stopWaiters.set(commandId, (ok) => {
+        clearTimeout(timer);
+        resolve(ok);
+      });
+      try {
+        agent.port.postMessage({
+          type: "stop",
+          requestId,
+          commandId,
+        } satisfies RecordFramePortMessage);
+      } catch {
+        clearTimeout(timer);
+        agent.stopWaiters.delete(commandId);
+        resolve(true);
+      }
+    });
+  }
+
+  async #startFrame(
+    recording: ArmedRecording,
+    tabId: number,
+    frame: BrowserFrame,
+  ): Promise<boolean> {
+    const message: RecordFrameStartMessage = {
+      type: RECORD_FRAME_START,
+      requestId: recording.requestId,
+      startedAtMs: recording.startedAtMs,
+    };
+    try {
+      const response = await this.#deps.sendToDocument(tabId, message, {
+        ...(frame.documentId ? { documentId: frame.documentId } : { frameId: frame.frameId }),
+      });
+      return isStarted(response);
+    } catch {
+      return false;
+    }
+  }
+
+  #cancelAgents(recording: ArmedRecording): void {
+    for (const agent of recording.agents.values()) {
+      try {
+        agent.port.postMessage({
+          type: "cancel",
+          requestId: recording.requestId,
+        } satisfies RecordFramePortMessage);
+      } catch {
+        // A destroyed Document has no remaining capture state to cancel.
+      }
+    }
+  }
+}
+
+function isStarted(value: unknown): boolean {
+  return typeof value === "object" && value !== null && (value as { ok?: unknown }).ok === true;
+}
+
+export const recordFrameCoordinator = new RecordFrameCoordinator();
@@ -0,0 +1,5 @@
+const REDIRECT_QUALIFIERS = new Set(["client_redirect", "server_redirect"]);
+
+export function hasRedirectQualifier(qualifiers?: readonly string[]): boolean {
+  return (qualifiers ?? []).some((qualifier) => REDIRECT_QUALIFIERS.has(qualifier));
+}
@@ -0,0 +1,140 @@
+import type { RenderedRef } from "@browser-skill/vom";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+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;
+}
+
+export interface RecordingDocumentScope {
+  frameId: string;
+  target: CdpTarget;
+}
+
+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[]>();
+  readonly #scopeByProducer = new Map<string, RecordingDocumentScope | null>();
+
+  constructor(
+    input: Pick<CaptureVomObservationResult, "rootFrameId" | "matchNodes" | "refs"> &
+      Partial<Pick<CaptureVomObservationResult, "frames">>,
+  ) {
+    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 frame of input.frames ?? []) {
+      const documentId = frame.recordingDocumentId;
+      if (!documentId) continue;
+      this.#scopeByProducer.set(
+        documentId,
+        this.#scopeByProducer.has(documentId)
+          ? null
+          : { frameId: frame.frameId, target: frame.target },
+      );
+    }
+    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) ?? [];
+  }
+
+  documentScope(producerId: string): RecordingDocumentScope | undefined {
+    return this.#scopeByProducer.get(producerId) ?? undefined;
+  }
+}
+
+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,
+  };
+}
@@ -0,0 +1,128 @@
+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 === "click" ||
+    draft.op === "hover" ||
+    draft.op === "fill" ||
+    draft.op === "press" ||
+    draft.op === "select"
+  );
+}
+
+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,
+      vomText: 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) }
+        : {}),
+    });
+  }
+}
@@ -0,0 +1,277 @@
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import type { StopReason, TraceV3 } from "@/transport/types";
+import { type DocumentSettleScope, waitForDocumentSettled } from "./document-settle";
+import type { RegisteredObservation } from "./observation-capture";
+import { RecordingObservationSession } from "./observation-session";
+import { inferMissingPostStates, SettleController } from "./settle-controller";
+import { RecordingStateRegistry } from "./state-registry";
+import { buildTraceV3 } from "./trace-builder-v3";
+import type { RecordingDraftStep, StepAnnotation } from "./types";
+
+interface TabRecordingContext {
+  session: RecordingObservationSession;
+  settle: SettleController;
+  pendingCapture: PendingCapture | null;
+  frameRefresh: Promise<void>;
+  frameRefreshAbort: AbortController | null;
+}
+
+interface PendingCapture {
+  promise: Promise<RegisteredObservation>;
+  abort: AbortController;
+}
+
+export class RecordingObservationRuntime {
+  readonly #cdp: CdpRunner;
+  readonly #tabsApi: ChromeTabsApi;
+  readonly #registry = new RecordingStateRegistry();
+  readonly #annotations: StepAnnotation[] = [];
+  readonly #contexts = new Map<number, TabRecordingContext>();
+  readonly #maxTokens?: number;
+  readonly #redactValues: boolean;
+
+  constructor(input: {
+    cdp: CdpRunner;
+    tabsApi: ChromeTabsApi;
+    maxTokens?: number;
+    redactValues?: boolean;
+  }) {
+    this.#cdp = input.cdp;
+    this.#tabsApi = input.tabsApi;
+    this.#maxTokens = input.maxTokens;
+    this.#redactValues = input.redactValues ?? false;
+  }
+
+  #context(tabId: number): TabRecordingContext {
+    const existing = this.#contexts.get(tabId);
+    if (existing) return existing;
+    const session = new RecordingObservationSession({
+      registry: this.#registry,
+      annotations: this.#annotations,
+      maxTokens: this.#maxTokens,
+      redactValues: this.#redactValues,
+    });
+    const context: TabRecordingContext = {
+      session,
+      settle: new SettleController({
+        session,
+        cdp: this.#cdp,
+        tabsApi: this.#tabsApi,
+        tabId,
+      }),
+      pendingCapture: null,
+      frameRefresh: Promise.resolve(),
+      frameRefreshAbort: null,
+    };
+    this.#contexts.set(tabId, context);
+    return context;
+  }
+
+  async #capture(tabId: number): Promise<RegisteredObservation> {
+    const context = this.#context(tabId);
+    if (context.pendingCapture) return context.pendingCapture.promise;
+
+    const abort = new AbortController();
+    let pending!: PendingCapture;
+    const promise = context.session.capture(this.#cdp, this.#tabsApi, tabId, abort.signal);
+    pending = {
+      abort,
+      promise: promise.finally(() => {
+        if (context.pendingCapture === pending) context.pendingCapture = null;
+      }),
+    };
+    context.pendingCapture = pending;
+    return pending.promise;
+  }
+
+  async captureInitial(tabId: number): Promise<void> {
+    const context = this.#context(tabId);
+    if (context.session.cursor.lastSettled) return;
+    await this.#capture(tabId);
+  }
+
+  /** Refresh the safe observation after a late child Document becomes usable. */
+  async refreshDocument(tabId: number, producerId: string): Promise<void> {
+    const context = this.#context(tabId);
+    context.frameRefreshAbort?.abort();
+    const abort = new AbortController();
+    context.frameRefreshAbort = abort;
+    const previous = context.frameRefresh;
+    const refresh = (async () => {
+      await previous;
+      if (abort.signal.aborted) return;
+      if (context.pendingCapture) await Promise.allSettled([context.pendingCapture.promise]);
+      if (abort.signal.aborted) return;
+
+      // The first capture discovers the safe producer -> CDP Document scope.
+      await this.#capture(tabId);
+      if (abort.signal.aborted) return;
+      const scope = context.session.cursor.lastSettled?.index.documentScope(producerId);
+      if (scope) {
+        await waitForDocumentSettled(this.#cdp, scope, { signal: abort.signal });
+      }
+      if (abort.signal.aborted) return;
+
+      // Capture again after the child SPA is quiet so the next action can be
+      // matched against refs that actually exist in its pre-action state.
+      await this.#capture(tabId);
+    })();
+    const tracked = refresh.catch(() => {});
+    context.frameRefresh = tracked;
+    try {
+      await refresh;
+    } finally {
+      if (context.frameRefresh === tracked) context.frameRefreshAbort = null;
+    }
+  }
+
+  async captureTabTransition(
+    fromTabId: number,
+    toTabId: number,
+  ): Promise<{ preStateId?: string; postStateId?: string; targetUrl?: string }> {
+    const from = this.#context(fromTabId);
+    await this.#flushContext(from);
+    if (!from.session.cursor.lastSettled) {
+      try {
+        await this.captureInitial(fromTabId);
+      } catch {
+        // A target-tab observation can still preserve the forward transition.
+      }
+    }
+
+    const to = this.#context(toTabId);
+    let target = to.session.cursor.lastSettled;
+    try {
+      target = await this.#capture(toTabId);
+    } catch {
+      // Reuse the last settled target state when a refresh races navigation.
+    }
+
+    const source = from.session.cursor.lastSettled;
+    return {
+      ...(source ? { preStateId: source.stateId } : {}),
+      ...(target ? { postStateId: target.stateId, targetUrl: target.url } : {}),
+    };
+  }
+
+  bindTabTransition(
+    draft: Extract<RecordingDraftStep, { op: "switch_tab" }>,
+    draftId: number,
+  ): void {
+    if (draft.preStateId) this.#registry.markStep(draft.preStateId, draftId);
+  }
+
+  async processDraft(
+    tabId: number,
+    drafts: RecordingDraftStep[],
+    draftIndex: number,
+    producerId?: string,
+  ): Promise<void> {
+    const draft = drafts[draftIndex];
+    if (!draft) return;
+    const context = this.#context(tabId);
+    if (!context.session.cursor.lastSettled) {
+      try {
+        await this.captureInitial(tabId);
+      } catch {
+        // Post-action settle can still provide a usable state.
+      }
+    }
+    const scope = producerId
+      ? context.session.cursor.lastSettled?.index.documentScope(producerId)
+      : undefined;
+    if (
+      producerId &&
+      (draft.op === "click" ||
+        draft.op === "hover" ||
+        draft.op === "fill" ||
+        draft.op === "press" ||
+        draft.op === "select")
+    ) {
+      draft.targetHint = {
+        ...(draft.targetHint ?? {}),
+        frameId: scope?.frameId ?? null,
+        geometrySpace: "local",
+      };
+    }
+    context.session.bindDraft(draft, draftIndex + 1, context.settle.hasPending);
+    context.settle.schedule(drafts, draftIndex, scope);
+  }
+
+  scheduleSettle(
+    tabId: number,
+    drafts: RecordingDraftStep[],
+    draftIndex: number,
+    scope?: DocumentSettleScope,
+  ): void {
+    this.#context(tabId).settle.schedule(drafts, draftIndex, scope);
+  }
+
+  clearRedirect(tabId: number): void {
+    this.#contexts.get(tabId)?.settle.clearRedirect();
+  }
+
+  scheduleRedirect(tabId: number, drafts: RecordingDraftStep[], url: string): void {
+    this.#context(tabId).settle.scheduleRedirect(drafts, url);
+  }
+
+  async #flushContext(context: TabRecordingContext): Promise<void> {
+    await context.frameRefresh;
+    if (context.pendingCapture) await Promise.allSettled([context.pendingCapture.promise]);
+    await context.settle.flushRedirects();
+    await context.settle.flush();
+  }
+
+  async flushRedirects(tabId: number): Promise<void> {
+    await this.#contexts.get(tabId)?.settle.flushRedirects();
+  }
+
+  async flush(): Promise<void> {
+    for (const context of this.#contexts.values()) await this.#flushContext(context);
+  }
+
+  async settleTrailing(tabId: number, drafts: RecordingDraftStep[]): Promise<void> {
+    const context = this.#context(tabId);
+    if (context.pendingCapture) await Promise.allSettled([context.pendingCapture.promise]);
+    if (!context.session.cursor.lastSettled) {
+      try {
+        await this.captureInitial(tabId);
+      } catch {
+        // The trace may remain observation-free when CDP is unavailable.
+      }
+    }
+    await context.settle.settleTrailing(drafts);
+    inferMissingPostStates(drafts);
+  }
+
+  cancel(): void {
+    for (const context of this.#contexts.values()) {
+      context.frameRefreshAbort?.abort();
+      context.pendingCapture?.abort.abort();
+      context.settle.cancel();
+    }
+  }
+
+  buildTrace(input: {
+    drafts: RecordingDraftStep[];
+    startedAt: string;
+    purpose?: string;
+    startUrl?: string;
+    stoppedBy: StopReason;
+    bskVersion: string;
+    includeTabSwitches?: boolean;
+  }): TraceV3 {
+    return buildTraceV3({
+      registry: this.#registry,
+      drafts: input.drafts,
+      annotations: this.#annotations,
+      startedAt: input.startedAt,
+      purpose: input.purpose,
+      startUrl: input.startUrl,
+      stoppedBy: input.stoppedBy,
+      bskVersion: input.bskVersion,
+      redactValues: this.#redactValues,
+      includeTabSwitches: input.includeTabSwitches,
+    });
+  }
+}
@@ -0,0 +1,233 @@
+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",
+      transitionQualifiers: ["server_redirect"],
+      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");
+  }
+}
@@ -0,0 +1,57 @@
+export interface RecordedStateEntry {
+  id: string;
+  url: string;
+  title?: string;
+  /** Rendered VOM text; capture indexes and source DOM/AX data never enter the registry. */
+  vomText: string;
+  truncated: boolean;
+  stepsHere: number[];
+}
+
+function stateIdentity(url: string, body: string): string {
+  return `${url}\0${body}`;
+}
+
+export class RecordingStateRegistry {
+  readonly #entriesById = new Map<string, RecordedStateEntry>();
+  readonly #idByIdentity = new Map<string, string>();
+  #nextId = 1;
+
+  register(input: {
+    url: string;
+    title?: string;
+    vomText: string;
+    truncated?: boolean;
+  }): RecordedStateEntry {
+    const identity = stateIdentity(input.url, input.vomText);
+    const existingId = this.#idByIdentity.get(identity);
+    if (existingId) {
+      const existing = this.#entriesById.get(existingId)!;
+      if (!existing.title && input.title) existing.title = input.title;
+      if (input.truncated) existing.truncated = true;
+      return existing;
+    }
+
+    const entry: RecordedStateEntry = {
+      id: `s${this.#nextId}`,
+      url: input.url,
+      ...(input.title ? { title: input.title } : {}),
+      vomText: input.vomText,
+      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);
+  }
+}
@@ -0,0 +1,155 @@
+import type { RecordStepPayload } from "../record-bridge";
+import { hasRedirectQualifier } from "./navigation-policy";
+import type { RecordingDraftStep, TargetMatchHint } from "./types";
+
+export interface RecordingStepBuffer {
+  steps: RecordingDraftStep[];
+  navigation: RecordingNavigationCursor;
+}
+
+export interface RecordingNavigationCursor {
+  currentUrl?: string;
+  pendingNavigation: boolean;
+  pendingNavigationDeadline?: number;
+}
+
+const NAVIGATION_TRIGGER_WINDOW_MS = 3_000;
+
+function toDraftStep(
+  payload: RecordStepPayload,
+  targetHint?: TargetMatchHint,
+): RecordingDraftStep | null {
+  const pageUrl = payload.page_url;
+  const common = {
+    ...(pageUrl ? { pageUrl } : {}),
+    ...(targetHint ? { targetHint } : {}),
+  };
+  switch (payload.op) {
+    case "click":
+      return payload.target ? { op: "click", captureTarget: payload.target, ...common } : null;
+    case "hover":
+      return payload.target ? { op: "hover", captureTarget: payload.target, ...common } : null;
+    case "fill":
+      return payload.target
+        ? {
+            op: "fill",
+            captureTarget: payload.target,
+            value: payload.value ?? "",
+            ...(payload.commit ? { commit: payload.commit } : {}),
+            ...(payload.redacted ? { redacted: true } : {}),
+            ...common,
+          }
+        : null;
+    case "press":
+      return payload.key
+        ? {
+            op: "press",
+            key: payload.key,
+            ...(payload.target ? { captureTarget: payload.target } : {}),
+            ...(payload.modifiers?.length ? { modifiers: payload.modifiers } : {}),
+            ...common,
+          }
+        : null;
+    case "select":
+      return payload.target && payload.values
+        ? {
+            op: "select",
+            captureTarget: payload.target,
+            values: payload.values,
+            ...(payload.labels?.length ? { labels: payload.labels } : {}),
+            ...common,
+          }
+        : null;
+    case "navigate":
+      return null;
+  }
+}
+
+function annotateLastStepNavigation(buffer: RecordingStepBuffer, url: string): number {
+  for (let index = buffer.steps.length - 1; index >= 0; index -= 1) {
+    const step = buffer.steps[index];
+    if (!step) continue;
+    if (step.op === "click" || step.op === "press" || step.op === "select" || step.op === "fill") {
+      step.navigatedTo = url;
+      return index;
+    }
+    break;
+  }
+  return -1;
+}
+
+export type NavigationObserveResult =
+  | { kind: "noop" }
+  | { kind: "annotated"; index: number }
+  | { kind: "appended"; index: number }
+  | { kind: "coalesce_redirect"; url: string };
+
+export function observeRecordedNavigation(
+  buffer: RecordingStepBuffer,
+  url: string,
+  causedByAction?: boolean,
+  transitionType?: string,
+  transitionQualifiers?: string[],
+): NavigationObserveResult {
+  const navigation = buffer.navigation;
+  if (!url || url === navigation.currentUrl) return { kind: "noop" };
+  navigation.currentUrl = url;
+
+  const pendingIsCurrent =
+    navigation.pendingNavigation &&
+    (navigation.pendingNavigationDeadline === undefined ||
+      navigation.pendingNavigationDeadline >= Date.now());
+
+  if (causedByAction === true || (causedByAction === undefined && pendingIsCurrent)) {
+    navigation.pendingNavigation = false;
+    navigation.pendingNavigationDeadline = undefined;
+    const annotatedIndex = annotateLastStepNavigation(buffer, url);
+    if (annotatedIndex >= 0) return { kind: "annotated", index: annotatedIndex };
+  } else {
+    navigation.pendingNavigation = false;
+    navigation.pendingNavigationDeadline = undefined;
+  }
+
+  if (hasRedirectQualifier(transitionQualifiers)) {
+    return { kind: "coalesce_redirect", url };
+  }
+  buffer.steps.push({
+    op: "navigate",
+    url,
+    pageUrl: url,
+    transitionType,
+    transitionQualifiers,
+  });
+  return { kind: "appended", index: buffer.steps.length - 1 };
+}
+
+export function appendRecordedPayload(
+  buffer: RecordingStepBuffer,
+  payload: RecordStepPayload,
+  targetHint?: TargetMatchHint,
+): number | null {
+  if (payload.op === "navigate") {
+    if (!payload.url) return null;
+    const result = observeRecordedNavigation(
+      buffer,
+      payload.url,
+      payload.navigation_caused_by_action,
+      payload.transitionType,
+      payload.transitionQualifiers,
+    );
+    return result.kind === "appended" ? result.index : null;
+  }
+  const step = toDraftStep(
+    { ...payload, page_url: payload.page_url ?? buffer.navigation.currentUrl },
+    targetHint,
+  );
+  if (!step) return null;
+  buffer.steps.push(step);
+  if (step.op === "click" || step.op === "press" || step.op === "select" || step.op === "fill") {
+    buffer.navigation.pendingNavigation = payload.expects_navigation === true;
+    buffer.navigation.pendingNavigationDeadline = buffer.navigation.pendingNavigation
+      ? Date.now() + NAVIGATION_TRIGGER_WINDOW_MS
+      : undefined;
+  }
+  return buffer.steps.length - 1;
+}
@@ -0,0 +1,61 @@
+import type { RecordingNavigationCursor } from "./step-buffer";
+
+export interface TabActivation {
+  tabId: number;
+  revision: number;
+}
+
+export class RecordingTabCoordinator {
+  readonly #navigationByTab = new Map<number, RecordingNavigationCursor>();
+  #activeTabId: number;
+  #currentTabId: number;
+  #activationRevision = 0;
+
+  constructor(initialTabId: number, initialUrl?: string) {
+    this.#activeTabId = initialTabId;
+    this.#currentTabId = initialTabId;
+    this.#navigationByTab.set(initialTabId, {
+      currentUrl: initialUrl,
+      pendingNavigation: false,
+    });
+  }
+
+  get activeTabId(): number {
+    return this.#activeTabId;
+  }
+
+  get currentTabId(): number {
+    return this.#currentTabId;
+  }
+
+  noteActivation(tabId: number): TabActivation {
+    this.#activeTabId = tabId;
+    this.#activationRevision += 1;
+    return { tabId, revision: this.#activationRevision };
+  }
+
+  isLatest(activation: TabActivation): boolean {
+    return (
+      activation.tabId === this.#activeTabId && activation.revision === this.#activationRevision
+    );
+  }
+
+  commit(tabId: number, currentUrl?: string): void {
+    if (currentUrl !== undefined) this.navigation(tabId).currentUrl = currentUrl;
+    this.#currentTabId = tabId;
+  }
+
+  navigation(tabId: number, fallbackUrl?: string): RecordingNavigationCursor {
+    const existing = this.#navigationByTab.get(tabId);
+    if (existing) {
+      if (!existing.currentUrl && fallbackUrl) existing.currentUrl = fallbackUrl;
+      return existing;
+    }
+    const created: RecordingNavigationCursor = {
+      currentUrl: fallbackUrl,
+      pendingNavigation: false,
+    };
+    this.#navigationByTab.set(tabId, created);
+    return created;
+  }
+}
@@ -0,0 +1,86 @@
+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,
+  geometrySpace: "top" | "local",
+): boolean {
+  const rect = geometrySpace === "local" ? candidate.geometry.localRect : candidate.geometry.rect;
+  return rect != null && rectMatches(geometry.rect, 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 {
+  if (input.hint?.frameId === null) return unmatchedTarget(input.fallback);
+  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, input.hint?.geometrySpace ?? "top"),
+      );
+    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);
+}
@@ -0,0 +1,92 @@
+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;
+  redactValues?: boolean;
+  includeTabSwitches?: boolean;
+}): TraceV3 {
+  const reduced = reduceTraceStepsV3(input.drafts, {
+    includeTabSwitches: input.includeTabSwitches,
+    redactValues: input.redactValues,
+  });
+  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.vomText,
+        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,
+  };
+}
@@ -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 +109,23 @@ 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":
-      return {
-        op: "hover",
-        id,
-        page,
-        target: step.target,
-      };
    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 +136,51 @@ 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),
      );
+    // `hover` only exists in Trace v3. Peers that negotiate v2 predate the
+    // step variant and fail to decode the whole result if we emit it.
+    case "hover":
+    case "scroll":
+    case "switch_tab":
+      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 +189,27 @@ 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,
+  };
 }
@@ -0,0 +1,154 @@
+import type { NavigationCause, StepV3 } from "@/transport/types";
+import { shouldIncludeDraft } from "./draft-policy";
+import { hasRedirectQualifier } from "./navigation-policy";
+import { unmatchedTarget } from "./target-matcher";
+import type { RecordingDraftStep } from "./types";
+
+interface CollapsedDraft {
+  draft: RecordingDraftStep;
+  draftIds: number[];
+}
+
+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 hasRedirectQualifier(step.transitionQualifiers);
+}
+
+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] } : {}),
+  }));
+}
+
+interface ReduceDraftOptions {
+  includeTabSwitches: boolean;
+  redactValues: boolean;
+}
+
+function reduceDraft(
+  draft: RecordingDraftStep,
+  id: number,
+  options: ReduceDraftOptions,
+): StepV3 | null {
+  if (!shouldIncludeDraft(draft)) return null;
+  if (draft.op === "switch_tab") {
+    if (!options.includeTabSwitches || !draft.preStateId || !draft.postStateId) return null;
+    return {
+      op: "switch_tab",
+      id,
+      state: draft.preStateId,
+      result: { state: draft.postStateId },
+    };
+  }
+  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":
+      const fillIsRedacted = options.redactValues || draft.redacted === true;
+      return {
+        op: "fill",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+        value: fillIsRedacted ? "***" : draft.value,
+        commit: draft.commit ?? "blur",
+        ...(fillIsRedacted ? { 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),
+        ...(!options.redactValues ? { 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[],
+  options: { includeTabSwitches?: boolean; redactValues?: boolean } = {},
+): ReducedTraceV3 {
+  const output: StepV3[] = [];
+  const stepIdByDraftId = new Map<number, number>();
+  for (const { draft, draftIds } of collapseRedirects(steps)) {
+    const step = reduceDraft(draft, output.length + 1, {
+      includeTabSwitches: options.includeTabSwitches === true,
+      redactValues: options.redactValues === true,
+    });
+    if (!step) continue;
+    output.push(step);
+    for (const draftId of draftIds) stepIdByDraftId.set(draftId, step.id);
+  }
+  return { steps: output, stepIdByDraftId };
+}
@@ -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`;
+}
@@ -0,0 +1,85 @@
+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 top frame; null means the source Document could not be resolved. */
+  frameId?: string | null;
+  geometrySpace?: "top" | "local";
+}
+
+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: "switch_tab" } & DraftStateLink)
+  | ({
+      op: "navigate";
+      url: string;
+      cause?: NavigationCause;
+      transitionType?: string;
+      transitionQualifiers?: string[];
+    } & DraftStateLink);
+
+export type TargetedRecordingDraft = Extract<
+  RecordingDraftStep,
+  { op: "click" | "hover" | "fill" | "press" | "select" }
+>;
@@ -0,0 +1,22 @@
+export const RECORD_DOCUMENT_ATTRIBUTE = "data-bsk-record-document";
+
+const RECORDING_DOCUMENT_ID_PATTERN =
+  /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
+const RECORDING_DOCUMENT_MARKER_PREFIX = "bsk:";
+
+export function recordingDocumentMarkerValue(identity: string): string {
+  if (!RECORDING_DOCUMENT_ID_PATTERN.test(identity)) {
+    throw new TypeError("recording Document identity must be a random UUID");
+  }
+  return `${RECORDING_DOCUMENT_MARKER_PREFIX}${identity}`;
+}
+
+/** Read BrowserSkill's opaque per-Document recording identity from captured attributes. */
+export function readRecordingDocumentIdentity(
+  attrs: Readonly<Record<string, string>>,
+): string | undefined {
+  const marker = attrs[RECORD_DOCUMENT_ATTRIBUTE];
+  if (!marker?.startsWith(RECORDING_DOCUMENT_MARKER_PREFIX)) return undefined;
+  const identity = marker.slice(RECORDING_DOCUMENT_MARKER_PREFIX.length);
+  return identity && RECORDING_DOCUMENT_ID_PATTERN.test(identity) ? identity : undefined;
+}
@@ -127,6 +127,38 @@ describe("requestBorrowConfirmation", () => {
    expect(message.requestId.length).toBeGreaterThan(0);
  });

+  it("proactively focuses the user window before sending the overlay message", async () => {
+    tabs.get.mockResolvedValueOnce({ id: 42, title: "Tab" });
+    windows.getLastFocused.mockResolvedValueOnce(
+      userWindowWithActiveTab({ windowId: 77, tabId: 7, url: "https://app.example/" }),
+    );
+    tabs.sendMessage.mockResolvedValueOnce({ type: "borrow-response", allowed: true });
+
+    const pending = requestBorrowConfirmation(42, {
+      deps: { tabs, windows, notifications },
+    });
+    await vi.runAllTimersAsync();
+    await pending;
+
+    expect(windows.update).toHaveBeenCalledWith(77, { focused: true });
+  });
+
+  it("still proceeds when proactive window focus fails", async () => {
+    tabs.get.mockResolvedValueOnce({ id: 42, title: "Tab" });
+    windows.getLastFocused.mockResolvedValueOnce(
+      userWindowWithActiveTab({ windowId: 77, tabId: 7, url: "https://app.example/" }),
+    );
+    windows.update.mockRejectedValueOnce(new Error("window gone"));
+    tabs.sendMessage.mockResolvedValueOnce({ type: "borrow-response", allowed: true });
+
+    const pending = requestBorrowConfirmation(42, {
+      deps: { tabs, windows, notifications },
+    });
+    await vi.runAllTimersAsync();
+
+    expect(await pending).toBe(true);
+  });
+
  it("sends confirmation to the borrow target when it is the active tab", async () => {
    tabs.get.mockResolvedValueOnce({ id: 42, title: "Active Tab" });
    windows.getLastFocused.mockResolvedValueOnce(
@@ -8,6 +8,7 @@ import type {
  RequestFrame,
 } from "@/transport/types";
 import { ToolDispatcher } from "../dispatcher";
+import { resetBrowserObservationForTests, setBrowserObservationAttachForTests } from "../record";

 type TestDispatcherCdp = NonNullable<ConstructorParameters<typeof ToolDispatcher>[0]["cdp"]>;

@@ -44,9 +45,72 @@ function makeRequest(method: string, params: unknown): RequestFrame {

 describe("ToolDispatcher", () => {
  afterEach(() => {
+    resetBrowserObservationForTests();
    vi.unstubAllGlobals();
  });

+  it("uses the configured recording runtime for start and stop", async () => {
+    const { transport, sent, deliver } = fakeTransport();
+    const sessions = new SessionManager({
+      agentWindow: {
+        create: vi.fn(async () => 4242),
+        remove: vi.fn(),
+        ensureActiveTab: vi.fn(async () => {}),
+      },
+    });
+    await sessions.start("aa11");
+    const tab = {
+      id: 7,
+      windowId: 4242,
+      active: true,
+      status: "complete",
+      url: "https://example.com/start",
+    } as chrome.tabs.Tab;
+    const frameCoordinator = {
+      begin: vi.fn(),
+      armTab: vi.fn(async () => true),
+      sourceFor: vi.fn(() => null),
+      stop: vi.fn(async () => true),
+      cancel: vi.fn(),
+    };
+    const sendToTab = vi.fn(async () => ({ ok: true }));
+    setBrowserObservationAttachForTests(
+      () => () => {},
+      () => () => {},
+    );
+    const dispatcher = new ToolDispatcher({
+      transport,
+      sessions,
+      recording: {
+        tabsApi: {
+          get: vi.fn(async () => tab),
+          query: vi.fn(async () => [tab]),
+        },
+        frameCoordinator,
+        sendToTab,
+      },
+    });
+    dispatcher.start();
+
+    deliver(
+      makeRequest("tool.record_start", {
+        session_id: "aa11",
+        url: "https://example.com/start",
+      }),
+    );
+    await vi.waitFor(() => expect(sent).toHaveLength(1));
+
+    expect(sent[0]).toMatchObject({ result: { tab_id: 7, recording: true } });
+    expect(frameCoordinator.begin).toHaveBeenCalledOnce();
+    expect(frameCoordinator.armTab).toHaveBeenCalledWith(expect.any(String), 7);
+
+    deliver({ id: "r-2", method: "tool.record_stop", params: { session_id: "aa11" } });
+    await vi.waitFor(() => expect(sent).toHaveLength(2));
+
+    expect(frameCoordinator.stop).toHaveBeenCalledOnce();
+    expect(sent[1]).toMatchObject({ id: "r-2", result: { trace: { steps: [] } } });
+  });
+
  it("routes tool.session_start to the SessionManager and replies with the window id", async () => {
    const { transport, sent, deliver } = fakeTransport();
    const sessions = new SessionManager({
@@ -168,6 +232,107 @@ describe("ToolDispatcher", () => {
    });
  });

+  it("bypasses and restores the control overlay for an upload trigger click", async () => {
+    const sendMessage = vi.fn(async () => undefined);
+    vi.stubGlobal("chrome", {
+      tabs: {
+        get: vi.fn(async () => ({ id: 7, windowId: 4242, active: true })),
+        query: vi.fn(async () => [{ id: 7, windowId: 4242, active: true }]),
+        sendMessage,
+      },
+    });
+    const { transport, sent, deliver } = fakeTransport();
+    const sessions = new SessionManager({
+      agentWindow: {
+        create: vi.fn(async () => 4242),
+        remove: vi.fn(async () => {}),
+        ensureActiveTab: vi.fn(async () => {}),
+      },
+    });
+    const ctx = await sessions.start("aa11");
+    ctx.refStore.set("e1", 123, { tabId: 7 });
+    const send = vi.fn(async <T>(_tabId: number, method: string, params?: object) => {
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } } as T;
+      }
+      if (method === "DOM.getContentQuads") {
+        return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] } as T;
+      }
+      if (method === "DOM.resolveNode") {
+        return { object: { objectId: "trigger-object" } } as T;
+      }
+      if (method === "DOM.describeNode") return { node: { backendNodeId: 456 } } as T;
+      if (method === "Runtime.callFunctionOn") {
+        const declaration = (params as { functionDeclaration?: string }).functionDeclaration ?? "";
+        if (declaration.includes("count: state.inputs.length")) {
+          return { result: { value: { count: 1, multiple: false } } } as T;
+        }
+        if (declaration.includes("inputs[0]")) {
+          return { result: { objectId: "input-object" } } as T;
+        }
+        return { result: { value: true } } as T;
+      }
+      if (method === "Runtime.evaluate") {
+        const expression = (params as { expression?: string }).expression ?? "";
+        if (expression.includes("overlayDetails")) {
+          return { result: { value: { hitIndex: 0 } } } as T;
+        }
+        if (expression.includes("overlayHostPresent")) {
+          return {
+            result: {
+              value: { overlayHostPresent: true, overlayHostConnected: true },
+            },
+          } as T;
+        }
+        if (expression.includes("count:")) {
+          return { result: { value: { count: 1, multiple: false } } } as T;
+        }
+        if (expression.includes("?.inputs[0]")) {
+          return { result: { objectId: "input-object" } } as T;
+        }
+        return { result: { value: true } } as T;
+      }
+      return {} as T;
+    });
+    const cdp = {
+      send,
+      detachSession: vi.fn(async () => {}),
+      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.upload", {
+        session_id: "aa11",
+        ref: "@e1",
+        files: [{ transfer_id: "tr_1", name: "test.png", staged_path: "/stage/test.png" }],
+      }),
+    );
+    await flushMicrotasks();
+    await vi.waitFor(() => expect(sent).toHaveLength(1));
+
+    expect(sent[0]).toMatchObject({ result: { tab_id: 7, file_names: ["test.png"] } });
+    expect(sendMessage).toHaveBeenNthCalledWith(1, 7, {
+      type: "bh-automation-bypass",
+      enabled: true,
+    });
+    expect(sendMessage).toHaveBeenNthCalledWith(2, 7, {
+      type: "bh-automation-bypass",
+      enabled: false,
+    });
+  });
+
  it("detaches CDP state before stopping a session", async () => {
    const { transport, sent, deliver } = fakeTransport();
    const sessions = new SessionManager({
@@ -0,0 +1,809 @@
+import { describe, expect, it, vi } from "vitest";
+import { SessionManager } from "@/session-manager/manager";
+import { type DownloadsApi, handleDownload } from "../download";
+import { captureBrowserDownload } from "../download-capture";
+import { uploadThroughActivatedFileInput } from "../file-input-transaction";
+import type { ResolvedActionTarget } from "../interaction";
+import type { CdpRunner } from "../shared";
+import { handleUpload } from "../upload";
+
+function sessions() {
+  return new SessionManager({
+    agentWindow: {
+      create: vi.fn(async () => 100),
+      remove: vi.fn(async () => {}),
+      ensureActiveTab: vi.fn(async () => {}),
+    },
+  });
+}
+
+function tabsApi() {
+  return {
+    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]),
+  };
+}
+
+function fakeEvent<T extends (...args: never[]) => unknown>() {
+  const listeners = new Set<T>();
+  return {
+    addListener: (listener: T) => listeners.add(listener),
+    removeListener: (listener: T) => listeners.delete(listener),
+    emit: (...args: Parameters<T>) => {
+      for (const listener of listeners) listener(...args);
+    },
+  };
+}
+
+function actionTarget(frameId?: string): ResolvedActionTarget {
+  return {
+    tab: { tabId: 4, windowId: 100, active: true },
+    backendNodeId: 123,
+    cdpTarget: { tabId: 4 },
+    ...(frameId ? { frameId } : {}),
+    usedRef: "e3",
+  };
+}
+
+function uploadCdp(
+  options: {
+    inputCount?: number;
+    multiple?: boolean;
+    chooser?: { frameId?: string; backendNodeId?: number; mode?: string };
+    pendingResolve?: boolean;
+  } = {},
+) {
+  const calls: Array<{ method: string; params?: object }> = [];
+  let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+  const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
+    calls.push({ method, params });
+    if (method === "Page.setInterceptFileChooserDialog") return {};
+    if (method === "Page.getLayoutMetrics")
+      return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+    if (method === "DOM.getContentQuads") return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] };
+    if (method === "DOM.resolveNode") {
+      if (options.pendingResolve) return new Promise<never>(() => {});
+      return { object: { objectId: "trigger-object" } };
+    }
+    if (method === "Runtime.callFunctionOn") {
+      const declaration = (params as { functionDeclaration?: string }).functionDeclaration ?? "";
+      if (declaration.includes("Object.defineProperty")) return { result: { value: true } };
+      if (declaration.includes("count: state.inputs.length")) {
+        return {
+          result: {
+            value: {
+              count: options.inputCount ?? 1,
+              multiple: options.multiple ?? true,
+            },
+          },
+        };
+      }
+      if (declaration.includes("inputs[0]")) {
+        return { result: { objectId: "input-object" } };
+      }
+      return { result: { value: true } };
+    }
+    if (method === "DOM.describeNode") return { node: { backendNodeId: 456 } };
+    if (
+      method === "Input.dispatchMouseEvent" &&
+      (params as { type?: string }).type === "mousePressed" &&
+      options.chooser
+    ) {
+      cdpEvent?.({ tabId: 4 }, "Page.fileChooserOpened", options.chooser);
+    }
+    return {};
+  });
+  const cdp: CdpRunner = {
+    send: send as unknown as CdpRunner["send"],
+    onEvent: (handler) => {
+      cdpEvent = handler;
+      return { dispose: vi.fn() };
+    },
+  };
+  return {
+    calls,
+    emitChooser: (event: { frameId?: string; backendNodeId?: number; mode?: string }) =>
+      cdpEvent?.({ tabId: 4 }, "Page.fileChooserOpened", event),
+    cdp,
+  };
+}
+
+describe("file transfer tools", () => {
+  it("captures the file input activated by the requested click and injects only staged paths", async () => {
+    const manager = sessions();
+    const ctx = await manager.start("s1");
+    ctx.refStore.set("e3", 123, { tabId: 4 });
+    const { cdp, calls } = uploadCdp();
+
+    const result = await handleUpload(
+      manager,
+      {
+        session_id: "s1",
+        ref: "@e3",
+        files: [
+          { transfer_id: "tr_1", name: "one.png", staged_path: "/private/stage/one" },
+          { transfer_id: "tr_2", name: "two.png", staged_path: "/private/stage/two" },
+        ],
+      },
+      { cdp, tabsApi: tabsApi() },
+    );
+
+    expect(result).toMatchObject({ tab_id: 4, file_names: ["one.png", "two.png"] });
+    expect(calls[0]).toEqual({
+      method: "Page.setInterceptFileChooserDialog",
+      params: { enabled: true },
+    });
+    expect(calls).toContainEqual({
+      method: "Page.setInterceptFileChooserDialog",
+      params: { enabled: false, cancel: true },
+    });
+    expect(calls).toContainEqual({
+      method: "DOM.setFileInputFiles",
+      params: { files: ["/private/stage/one", "/private/stage/two"], backendNodeId: 456 },
+    });
+  });
+
+  it("fails immediately when the trigger does not activate a file input", async () => {
+    const { cdp } = uploadCdp({ inputCount: 0 });
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger: async () => ({ tab_id: 4, x: 10, y: 10 }),
+    });
+
+    expect(result).toMatchObject({
+      code: "unsupported",
+      data: { reason: "file_input_not_activated", phase: "resolve_input" },
+    });
+  });
+
+  it("fails before clicking when chooser interception is unavailable", async () => {
+    const trigger = vi.fn(async () => ({ tab_id: 4, x: 10, y: 10 }));
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId: number, method: string) => {
+        if (method === "Page.setInterceptFileChooserDialog") {
+          throw new Error("method unavailable");
+        }
+        return {};
+      }) as CdpRunner["send"],
+    };
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger,
+    });
+
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { effect_state: "none", phase: "arm_interception" },
+    });
+    expect(trigger).not.toHaveBeenCalled();
+  });
+
+  it("uses an exact chooser event as an independent input-location signal", async () => {
+    const { cdp, calls, emitChooser } = uploadCdp({ inputCount: 0 });
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget("f1"),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger: async () => {
+        emitChooser({ frameId: "f1", backendNodeId: 789, mode: "selectSingle" });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({ multiple: false });
+    expect(calls).toContainEqual({
+      method: "DOM.setFileInputFiles",
+      params: { files: ["/private/stage/one"], backendNodeId: 789 },
+    });
+  });
+
+  it("reports a File System Access picker without waiting for a timeout", async () => {
+    const { cdp, emitChooser } = uploadCdp({
+      inputCount: 0,
+    });
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget("f1"),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger: async () => {
+        emitChooser({ frameId: "f1", mode: "selectSingle" });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({
+      code: "unsupported",
+      message: "upload trigger invoked a non-input file picker",
+      data: { reason: "file_input_not_activated", phase: "resolve_input" },
+    });
+  });
+
+  it("bounds a stuck file-input probe", async () => {
+    const { cdp } = uploadCdp({ pendingResolve: true });
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 5,
+      trigger: vi.fn(),
+    });
+
+    expect(result).toMatchObject({
+      code: "timeout",
+      data: { reason: "file_input_probe_failed", phase: "arm_input_probe" },
+    });
+  });
+
+  it("does not dispatch browser work when upload is already cancelled", async () => {
+    const controller = new AbortController();
+    controller.abort();
+    const { cdp, calls } = uploadCdp();
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      signal: controller.signal,
+      trigger: vi.fn(),
+    });
+
+    expect(result).toMatchObject({
+      code: "cancelled",
+      data: { effect_state: "none", phase: "arm_interception" },
+    });
+    expect(calls).not.toContainEqual({
+      method: "Page.setInterceptFileChooserDialog",
+      params: { enabled: true },
+    });
+    expect(calls.some((call) => call.method === "DOM.setFileInputFiles")).toBe(false);
+  });
+
+  it("stops before file assignment when cancellation interrupts input resolution", async () => {
+    const controller = new AbortController();
+    const fixture = uploadCdp();
+    const originalSend = fixture.cdp.send;
+    let markProbeStarted!: () => void;
+    const probeStarted = new Promise<void>((resolve) => {
+      markProbeStarted = resolve;
+    });
+    fixture.cdp.send = vi.fn((tabId: number, method: string, params?: object) => {
+      const declaration = (params as { functionDeclaration?: string } | undefined)
+        ?.functionDeclaration;
+      if (
+        method === "Runtime.callFunctionOn" &&
+        declaration?.includes("count: state.inputs.length")
+      ) {
+        markProbeStarted();
+        return new Promise<never>(() => {});
+      }
+      return originalSend(tabId, method, params);
+    }) as CdpRunner["send"];
+
+    const transaction = uploadThroughActivatedFileInput({
+      cdp: fixture.cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 1_000,
+      signal: controller.signal,
+      trigger: async () => ({ tab_id: 4, x: 10, y: 10 }),
+    });
+    await probeStarted;
+    controller.abort();
+    const result = await transaction;
+
+    expect(result).toMatchObject({
+      code: "cancelled",
+      data: { effect_state: "none", phase: "resolve_input" },
+    });
+    expect(fixture.calls.some((call) => call.method === "DOM.setFileInputFiles")).toBe(false);
+  });
+
+  it("disarms chooser interception when its enable response times out", async () => {
+    const calls: Array<{ method: string; params?: object }> = [];
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId: number, method: string, params?: object) => {
+        calls.push({ method, params });
+        if (
+          method === "Page.setInterceptFileChooserDialog" &&
+          (params as { enabled?: boolean }).enabled
+        ) {
+          return new Promise<never>(() => {});
+        }
+        return {};
+      }) as CdpRunner["send"],
+    };
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 5,
+      trigger: vi.fn(),
+    });
+
+    expect(result).toMatchObject({
+      code: "timeout",
+      data: { effect_state: "none", phase: "arm_interception" },
+    });
+    expect(calls).toContainEqual({
+      method: "Page.setInterceptFileChooserDialog",
+      params: { enabled: false, cancel: true },
+    });
+  });
+
+  it("marks a timed-out file assignment unknown and detaches browser state", async () => {
+    const fixture = uploadCdp();
+    const originalSend = fixture.cdp.send;
+    const detach = vi.fn(async () => {});
+    fixture.cdp.detach = detach;
+    fixture.cdp.send = vi.fn((tabId: number, method: string, params?: object) => {
+      if (method === "DOM.setFileInputFiles") return new Promise<never>(() => {});
+      return originalSend(tabId, method, params);
+    }) as CdpRunner["send"];
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp: fixture.cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 10,
+      trigger: async () => ({ tab_id: 4, x: 10, y: 10 }),
+    });
+
+    expect(result).toMatchObject({
+      code: "timeout",
+      data: { effect_state: "unknown", phase: "set_files" },
+    });
+    expect(detach).toHaveBeenCalledWith(4);
+  });
+
+  it("routes one exact-target download through a browser-relative capability", async () => {
+    const manager = sessions();
+    const ctx = await manager.start("s1");
+    ctx.refStore.set("e3", 123, { tabId: 4 });
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 9,
+      url: "https://example.test/result.zip",
+      finalUrl: "https://example.test/result.zip",
+      filename: "result.zip",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: 12,
+      mime: "application/zip",
+      danger: "safe",
+    } as chrome.downloads.DownloadItem;
+    const completed = {
+      ...initial,
+      filename: "/profile/Downloads/BrowserSkill/tr_1/result.zip",
+      state: "complete",
+      fileSize: 12,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => [completed]),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    let suggested: chrome.downloads.DownloadFilenameSuggestion | undefined;
+    const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
+      if (method === "Page.getLayoutMetrics")
+        return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+      if (method === "DOM.getContentQuads") return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] };
+      if (
+        method === "Input.dispatchMouseEvent" &&
+        (params as { type?: string }).type === "mousePressed"
+      ) {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: "result.zip",
+        });
+        await new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, (value) => {
+            suggested = value;
+            resolve();
+          });
+        });
+        onCreated.emit(completed);
+      }
+      return {};
+    });
+    const cdp: CdpRunner = {
+      send: send as unknown as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+
+    const result = await handleDownload(
+      manager,
+      { session_id: "s1", ref: "@e3", browser_relative_dir: "BrowserSkill/tr_1" },
+      { cdp, tabsApi: tabsApi(), downloads },
+    );
+
+    expect(suggested).toEqual({
+      filename: "BrowserSkill/tr_1/result.zip",
+      conflictAction: "overwrite",
+    });
+    expect(result).toMatchObject({
+      tab_id: 4,
+      suggested_filename: "result.zip",
+      byte_size: 12,
+      browser_path: completed.filename,
+    });
+  });
+
+  it("does not claim a download without an intent from the exact target", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => []),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as unknown as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+    const unrelated = {
+      id: 17,
+      url: "https://example.test/unrelated.zip",
+      finalUrl: "https://example.test/unrelated.zip",
+      filename: "unrelated.zip",
+      state: "in_progress",
+    } as chrome.downloads.DownloadItem;
+    let defaultSuggestionCalled = false;
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4, sessionId: "expected-child" },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_1",
+      timeoutMs: 5,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4, sessionId: "other-child" }, "Page.downloadWillBegin", {
+          url: unrelated.url,
+          suggestedFilename: unrelated.filename,
+        });
+        onDeterminingFilename.emit(unrelated, (suggestion) => {
+          defaultSuggestionCalled = suggestion === undefined;
+        });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(defaultSuggestionCalled).toBe(true);
+    expect(downloads.cancel).not.toHaveBeenCalled();
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { reason: "download_capture_failed" },
+    });
+  });
+
+  it("correlates a filename candidate that arrives before the CDP intent", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 21,
+      url: "https://example.test/candidate-first.bin",
+      finalUrl: "https://example.test/candidate-first.bin",
+      filename: "candidate-first.bin",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: 4,
+      bytesReceived: 0,
+    } as chrome.downloads.DownloadItem;
+    const complete = {
+      ...initial,
+      state: "complete",
+      fileSize: 4,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => [complete]),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+    let suggestion: chrome.downloads.DownloadFilenameSuggestion | undefined;
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_21",
+      timeoutMs: 1_000,
+      trigger: async () => {
+        const suggested = new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, (value) => {
+            suggestion = value;
+            resolve();
+          });
+        });
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: initial.filename,
+        });
+        await suggested;
+        onCreated.emit(complete);
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(suggestion).toEqual({
+      filename: "BrowserSkill/tr_21/candidate-first.bin",
+      conflictAction: "overwrite",
+    });
+    expect(result).toMatchObject({ item: { id: 21, state: "complete" } });
+  });
+
+  it("removes a completed download when the final size exceeds the limit", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 22,
+      url: "https://example.test/oversized.bin",
+      finalUrl: "https://example.test/oversized.bin",
+      filename: "oversized.bin",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: -1,
+      bytesReceived: 0,
+    } as chrome.downloads.DownloadItem;
+    const complete = {
+      ...initial,
+      filename: "/profile/Downloads/BrowserSkill/tr_22/oversized.bin",
+      state: "complete",
+      fileSize: 8,
+      totalBytes: 8,
+      bytesReceived: 8,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => [complete]),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_22",
+      maxByteSize: 4,
+      timeoutMs: 1_000,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: initial.filename,
+        });
+        await new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, () => resolve());
+        });
+        onCreated.emit(initial);
+        onChanged.emit({ id: initial.id, state: { current: "complete" } });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { reason: "download_capture_failed", effect_state: "committed" },
+    });
+    expect(downloads.removeFile).toHaveBeenCalledWith(initial.id);
+    expect(downloads.cancel).not.toHaveBeenCalled();
+  });
+
+  it.each([
+    ["cancel resolves", false],
+    ["cancel reports that completion won", true],
+  ])("reconciles a download that completes while %s", async (_label, cancelThrows) => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 23,
+      url: "https://example.test/racing.bin",
+      finalUrl: "https://example.test/racing.bin",
+      filename: "racing.bin",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: -1,
+      bytesReceived: 0,
+    } as chrome.downloads.DownloadItem;
+    const complete = {
+      ...initial,
+      filename: "/profile/Downloads/BrowserSkill/tr_23/racing.bin",
+      state: "complete",
+      fileSize: 4,
+      totalBytes: 4,
+      bytesReceived: 4,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn().mockResolvedValueOnce([initial]).mockResolvedValueOnce([complete]),
+      cancel: vi.fn(async () => {
+        if (cancelThrows) throw new Error("download already complete");
+      }),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_23",
+      timeoutMs: 80,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: initial.filename,
+        });
+        await new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, () => resolve());
+        });
+        onCreated.emit(initial);
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { reason: "download_capture_failed", effect_state: "committed" },
+    });
+    expect(downloads.cancel).toHaveBeenCalledWith(initial.id);
+    expect(downloads.removeFile).toHaveBeenCalledWith(initial.id);
+    expect(result).not.toMatchObject({ data: { cleanup_state: "failed" } });
+  });
+
+  it("rejects ambiguous attribution without cancelling either unclaimed download", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => []),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+    const defaults: number[] = [];
+    const candidate = (id: number) =>
+      ({
+        id,
+        url: "https://example.test/same.bin",
+        finalUrl: "https://example.test/same.bin",
+        filename: "same.bin",
+        state: "in_progress",
+      }) as chrome.downloads.DownloadItem;
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_ambiguous",
+      timeoutMs: 100,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: "https://example.test/same.bin",
+          suggestedFilename: "same.bin",
+        });
+        for (const id of [31, 32]) {
+          onDeterminingFilename.emit(candidate(id), (value) => {
+            if (value === undefined) defaults.push(id);
+          });
+        }
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(defaults.sort()).toEqual([31, 32]);
+    expect(downloads.cancel).not.toHaveBeenCalled();
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { effect_state: "unknown", phase: "attribution" },
+    });
+  });
+});
@@ -1656,7 +1656,7 @@ describe("buildVomScene", () => {

    const scene = buildVomScene(axNodes, captured);
    expect(scene.nodes.find((n) => n.id === 20)).toEqual(
-      expect.objectContaining({ id: 20, role: "generic", cursor: "pointer" }),
+      expect.objectContaining({ id: 20, role: "button", name: "close", cursor: "pointer" }),
    );
    const rendered = renderVom(scene);
    expect(rendered.text).toContain('@e1 button "close"');
@@ -1732,7 +1732,7 @@ describe("buildVomScene", () => {
    };

    const scene = buildVomScene(axNodes, captured);
-    expect(scene.nodes.find((n) => n.id === 20)?.role).toBe("generic");
+    expect(scene.nodes.find((n) => n.id === 20)).toBeUndefined();
    expect(scene.nodes.find((n) => n.id === 30)?.role).toBe("link");
  });

@@ -1801,9 +1801,9 @@ describe("buildVomScene", () => {

    const scene = buildVomScene(axNodes, captured);
    expect(scene.nodes.find((n) => n.id === 20)).toEqual(
-      expect.objectContaining({ id: 20, role: "generic", attrs: { "aria-label": "收藏" } }),
+      expect.objectContaining({ id: 20, role: "button", attrs: { "aria-label": "收藏" } }),
    );
-    expect(scene.nodes.find((n) => n.id === 30)?.role).toBe("generic");
+    expect(scene.nodes.find((n) => n.id === 30)).toBeUndefined();
    const rendered = renderVom(scene);
    expect(rendered.text).toContain('@e1 button "收藏"');
    expect(rendered.refs.map(({ ref, backendNodeId }) => ({ ref, backendNodeId }))).toEqual([
@@ -1904,36 +1904,41 @@ describe("buildVomScene", () => {
        backendDOMNodeId: 20,
      },
    ];
-    const scene = buildVomScene(axNodes, {
-      viewport: { width: 1000, height: 800 },
-      iframeNodes: new Map(),
-      excludedBackendNodeIds: new Set(),
-      surfaceProbes: [
-        { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["Shoes", "Bags"] },
-      ],
-      nodes: [
-        {
-          backendNodeId: 10,
-          parentBackendNodeId: null,
-          tag: "body",
-          attrs: {},
-          rect: { x: 0, y: 0, w: 1000, h: 800 },
-          paintOrder: 0,
-          position: "static",
-          pointerEvents: "auto",
-        },
-        {
-          backendNodeId: 20,
-          parentBackendNodeId: 10,
-          tag: "button",
-          attrs: {},
-          rect: { x: 20, y: 20, w: 120, h: 40 },
-          paintOrder: 1,
-          position: "static",
-          pointerEvents: "auto",
-        },
-      ],
-    });
+    const scene = buildVomScene(
+      axNodes,
+      {
+        viewport: { width: 1000, height: 800 },
+        iframeNodes: new Map(),
+        excludedBackendNodeIds: new Set(),
+        nodes: [
+          {
+            backendNodeId: 10,
+            parentBackendNodeId: null,
+            tag: "body",
+            attrs: {},
+            rect: { x: 0, y: 0, w: 1000, h: 800 },
+            paintOrder: 0,
+            position: "static",
+            pointerEvents: "auto",
+          },
+          {
+            backendNodeId: 20,
+            parentBackendNodeId: 10,
+            tag: "button",
+            attrs: {},
+            rect: { x: 20, y: 20, w: 120, h: 40 },
+            paintOrder: 1,
+            position: "static",
+            pointerEvents: "auto",
+          },
+        ],
+      },
+      {
+        surfaceProbes: [
+          { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["Shoes", "Bags"] },
+        ],
+      },
+    );

    expect(scene.surfaces).toEqual([
      { triggerId: 20, triggerAction: "hover", subItems: ["Shoes", "Bags"] },
@@ -1957,46 +1962,51 @@ describe("buildVomScene", () => {
        backendDOMNodeId: 21,
      },
    ];
-    const scene = buildVomScene(axNodes, {
-      viewport: { width: 1000, height: 800 },
-      iframeNodes: new Map(),
-      excludedBackendNodeIds: new Set(),
-      surfaceProbes: [
-        { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["My profile"] },
-      ],
-      nodes: [
-        {
-          backendNodeId: 10,
-          parentBackendNodeId: null,
-          tag: "body",
-          attrs: {},
-          rect: { x: 0, y: 0, w: 1000, h: 800 },
-          paintOrder: 0,
-          position: "static",
-          pointerEvents: "auto",
-        },
-        {
-          backendNodeId: 20,
-          parentBackendNodeId: 10,
-          tag: "div",
-          attrs: { class: "tg-avatar" },
-          rect: { x: 900, y: 10, w: 30, h: 30 },
-          paintOrder: 1,
-          position: "static",
-          pointerEvents: "auto",
-        },
-        {
-          backendNodeId: 21,
-          parentBackendNodeId: 20,
-          tag: "div",
-          attrs: { class: "tg-avatar__inner" },
-          rect: { x: 902, y: 12, w: 26, h: 26 },
-          paintOrder: 2,
-          position: "static",
-          pointerEvents: "auto",
-        },
-      ],
-    });
+    const scene = buildVomScene(
+      axNodes,
+      {
+        viewport: { width: 1000, height: 800 },
+        iframeNodes: new Map(),
+        excludedBackendNodeIds: new Set(),
+        nodes: [
+          {
+            backendNodeId: 10,
+            parentBackendNodeId: null,
+            tag: "body",
+            attrs: {},
+            rect: { x: 0, y: 0, w: 1000, h: 800 },
+            paintOrder: 0,
+            position: "static",
+            pointerEvents: "auto",
+          },
+          {
+            backendNodeId: 20,
+            parentBackendNodeId: 10,
+            tag: "div",
+            attrs: { class: "tg-avatar" },
+            rect: { x: 900, y: 10, w: 30, h: 30 },
+            paintOrder: 1,
+            position: "static",
+            pointerEvents: "auto",
+          },
+          {
+            backendNodeId: 21,
+            parentBackendNodeId: 20,
+            tag: "div",
+            attrs: { class: "tg-avatar__inner" },
+            rect: { x: 902, y: 12, w: 26, h: 26 },
+            paintOrder: 2,
+            position: "static",
+            pointerEvents: "auto",
+          },
+        ],
+      },
+      {
+        surfaceProbes: [
+          { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["My profile"] },
+        ],
+      },
+    );

    expect(renderVom(scene).text).toContain('@e1 button "image" [hover first: My profile]');
  });
@@ -2017,48 +2027,53 @@ describe("buildVomScene", () => {
        backendDOMNodeId: 21,
      },
    ];
-    const scene = buildVomScene(axNodes, {
-      viewport: { width: 1000, height: 800 },
-      iframeNodes: new Map(),
-      excludedBackendNodeIds: new Set(),
-      surfaceProbes: [
-        { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["My profile"] },
-        { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["Sign out"] },
-        { triggerBackendNodeId: 21, triggerAction: "hover", subItems: ["Settings"] },
-      ],
-      nodes: [
-        {
-          backendNodeId: 10,
-          parentBackendNodeId: null,
-          tag: "body",
-          attrs: {},
-          rect: { x: 0, y: 0, w: 1000, h: 800 },
-          paintOrder: 0,
-          position: "static",
-          pointerEvents: "auto",
-        },
-        {
-          backendNodeId: 20,
-          parentBackendNodeId: 10,
-          tag: "div",
-          attrs: { class: "tg-avatar" },
-          rect: { x: 900, y: 10, w: 30, h: 30 },
-          paintOrder: 1,
-          position: "static",
-          pointerEvents: "auto",
-        },
-        {
-          backendNodeId: 21,
-          parentBackendNodeId: 20,
-          tag: "div",
-          attrs: { class: "tg-avatar__inner" },
-          rect: { x: 902, y: 12, w: 26, h: 26 },
-          paintOrder: 2,
-          position: "static",
-          pointerEvents: "auto",
-        },
-      ],
-    });
+    const scene = buildVomScene(
+      axNodes,
+      {
+        viewport: { width: 1000, height: 800 },
+        iframeNodes: new Map(),
+        excludedBackendNodeIds: new Set(),
+        nodes: [
+          {
+            backendNodeId: 10,
+            parentBackendNodeId: null,
+            tag: "body",
+            attrs: {},
+            rect: { x: 0, y: 0, w: 1000, h: 800 },
+            paintOrder: 0,
+            position: "static",
+            pointerEvents: "auto",
+          },
+          {
+            backendNodeId: 20,
+            parentBackendNodeId: 10,
+            tag: "div",
+            attrs: { class: "tg-avatar" },
+            rect: { x: 900, y: 10, w: 30, h: 30 },
+            paintOrder: 1,
+            position: "static",
+            pointerEvents: "auto",
+          },
+          {
+            backendNodeId: 21,
+            parentBackendNodeId: 20,
+            tag: "div",
+            attrs: { class: "tg-avatar__inner" },
+            rect: { x: 902, y: 12, w: 26, h: 26 },
+            paintOrder: 2,
+            position: "static",
+            pointerEvents: "auto",
+          },
+        ],
+      },
+      {
+        surfaceProbes: [
+          { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["My profile"] },
+          { triggerBackendNodeId: 20, triggerAction: "hover", subItems: ["Sign out"] },
+          { triggerBackendNodeId: 21, triggerAction: "hover", subItems: ["Settings"] },
+        ],
+      },
+    );

    expect(scene.surfaces).toEqual([
      { triggerId: 21, triggerAction: "hover", subItems: ["My profile"] },
@@ -2081,57 +2096,62 @@ describe("buildVomScene", () => {
        backendDOMNodeId: 21,
      },
    ];
-    const scene = buildVomScene(axNodes, {
-      viewport: { width: 1000, height: 800 },
-      iframeNodes: new Map(),
-      excludedBackendNodeIds: new Set(),
-      surfaceProbes: [
-        {
-          triggerBackendNodeId: 20,
-          triggerPoint: { x: 915, y: 25 },
-          triggerAction: "hover",
-          subItems: ["My profile", "Sign out"],
-        },
-      ],
-      nodes: [
-        {
-          backendNodeId: 10,
-          parentBackendNodeId: null,
-          tag: "body",
-          attrs: {},
-          rect: { x: 0, y: 0, w: 1000, h: 800 },
-          paintOrder: 0,
-          position: "static",
-          pointerEvents: "auto",
-          cursor: "auto",
-        },
-        {
-          backendNodeId: 20,
-          parentBackendNodeId: 10,
-          tag: "div",
-          attrs: { class: "tg-avatar" },
-          rect: { x: 900, y: 10, w: 30, h: 30 },
-          paintOrder: 1,
-          position: "static",
-          pointerEvents: "auto",
-          cursor: "pointer",
-        },
-        {
-          backendNodeId: 21,
-          parentBackendNodeId: 20,
-          tag: "div",
-          attrs: { class: "tg-avatar__inner" },
-          rect: { x: 902, y: 12, w: 26, h: 26 },
-          paintOrder: 2,
-          position: "static",
-          pointerEvents: "auto",
-          cursor: "pointer",
-        },
-      ],
-    });
+    const scene = buildVomScene(
+      axNodes,
+      {
+        viewport: { width: 1000, height: 800 },
+        iframeNodes: new Map(),
+        excludedBackendNodeIds: new Set(),
+        nodes: [
+          {
+            backendNodeId: 10,
+            parentBackendNodeId: null,
+            tag: "body",
+            attrs: {},
+            rect: { x: 0, y: 0, w: 1000, h: 800 },
+            paintOrder: 0,
+            position: "static",
+            pointerEvents: "auto",
+            cursor: "auto",
+          },
+          {
+            backendNodeId: 20,
+            parentBackendNodeId: 10,
+            tag: "div",
+            attrs: { class: "tg-avatar" },
+            rect: { x: 900, y: 10, w: 30, h: 30 },
+            paintOrder: 1,
+            position: "static",
+            pointerEvents: "auto",
+            cursor: "pointer",
+          },
+          {
+            backendNodeId: 21,
+            parentBackendNodeId: 20,
+            tag: "div",
+            attrs: { class: "tg-avatar__inner" },
+            rect: { x: 902, y: 12, w: 26, h: 26 },
+            paintOrder: 2,
+            position: "static",
+            pointerEvents: "auto",
+            cursor: "pointer",
+          },
+        ],
+      },
+      {
+        surfaceProbes: [
+          {
+            triggerBackendNodeId: 20,
+            triggerPoint: { x: 915, y: 25 },
+            triggerAction: "hover",
+            subItems: ["My profile", "Sign out"],
+          },
+        ],
+      },
+    );

    expect(scene.surfaces).toEqual([
-      { triggerId: 21, triggerAction: "hover", subItems: ["My profile", "Sign out"] },
+      { triggerId: 20, triggerAction: "hover", subItems: ["My profile", "Sign out"] },
    ]);
    expect(renderVom(scene).text).toContain(
      '@e1 button "image" [hover first: My profile | Sign out]',
@@ -2154,41 +2174,46 @@ describe("buildVomScene", () => {
        backendDOMNodeId: 42,
      },
    ];
-    const scene = buildVomScene(axNodes, {
-      viewport: { width: 1000, height: 800 },
-      iframeNodes: new Map(),
-      excludedBackendNodeIds: new Set(),
-      surfaceProbes: [
-        {
-          triggerBackendNodeId: 999,
-          triggerPoint: { x: 900, y: 20 },
-          triggerAction: "hover",
-          subItems: ["My profile"],
-        },
-      ],
-      nodes: [
-        {
-          backendNodeId: 10,
-          parentBackendNodeId: null,
-          tag: "body",
-          attrs: {},
-          rect: { x: 0, y: 0, w: 1000, h: 800 },
-          paintOrder: 0,
-          position: "static",
-          pointerEvents: "auto",
-        },
-        {
-          backendNodeId: 42,
-          parentBackendNodeId: 10,
-          tag: "a",
-          attrs: {},
-          rect: { x: 860, y: 120, w: 40, h: 30 },
-          paintOrder: 1,
-          position: "static",
-          pointerEvents: "auto",
-        },
-      ],
-    });
+    const scene = buildVomScene(
+      axNodes,
+      {
+        viewport: { width: 1000, height: 800 },
+        iframeNodes: new Map(),
+        excludedBackendNodeIds: new Set(),
+        nodes: [
+          {
+            backendNodeId: 10,
+            parentBackendNodeId: null,
+            tag: "body",
+            attrs: {},
+            rect: { x: 0, y: 0, w: 1000, h: 800 },
+            paintOrder: 0,
+            position: "static",
+            pointerEvents: "auto",
+          },
+          {
+            backendNodeId: 42,
+            parentBackendNodeId: 10,
+            tag: "a",
+            attrs: {},
+            rect: { x: 860, y: 120, w: 40, h: 30 },
+            paintOrder: 1,
+            position: "static",
+            pointerEvents: "auto",
+          },
+        ],
+      },
+      {
+        surfaceProbes: [
+          {
+            triggerBackendNodeId: 999,
+            triggerPoint: { x: 900, y: 20 },
+            triggerAction: "hover",
+            subItems: ["My profile"],
+          },
+        ],
+      },
+    );

    expect(scene.surfaces).toBeUndefined();
    expect(renderVom(scene).text).not.toContain("[hover first:");
@@ -2606,7 +2631,106 @@ describe("handleSnapshot", () => {
    );
  });

-  it("enables conditional surface probing for semantic observe", async () => {
+  it("hovers the page only after the accessibility tree has been captured", async () => {
+    // Hovering can open menus and reflow the page. Probing between the DOM and
+    // AX captures would leave the two halves of one observation describing the
+    // page on either side of that change.
+    const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
+    await sm.start("aa11");
+    const root: CdpAxNode = {
+      nodeId: "1",
+      role: { type: "role", value: "RootWebArea" },
+      name: { type: "computedString", value: "Example" },
+      backendDOMNodeId: 100,
+      childIds: ["2"],
+    };
+    const button: CdpAxNode = {
+      nodeId: "2",
+      parentId: "1",
+      role: { type: "role", value: "button" },
+      name: { type: "computedString", value: "Products" },
+      backendDOMNodeId: 200,
+    };
+    const strings = ["body", "button", "position", "static", "pointer-events", "auto", "cursor"];
+    const i = (s: string) => strings.indexOf(s);
+    const methodOrder: string[] = [];
+    const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
+      methodOrder.push(method);
+      if (method === "Accessibility.enable") return {};
+      if (method === "Accessibility.getFullAXTree") return { nodes: [root, button] };
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 1000, clientHeight: 800, pageX: 0, pageY: 0 } };
+      }
+      if (method === "DOMSnapshot.enable") return {};
+      if (method === "DOMSnapshot.captureSnapshot") {
+        return {
+          strings,
+          documents: [
+            {
+              nodes: {
+                parentIndex: [-1, 0],
+                nodeName: [i("body"), i("button")],
+                backendNodeId: [100, 200],
+                attributes: [[], []],
+              },
+              layout: {
+                nodeIndex: [0, 1],
+                styles: [
+                  [i("static"), i("auto"), i("auto")],
+                  [i("static"), i("auto"), i("auto")],
+                ],
+                bounds: [
+                  [0, 0, 1000, 800],
+                  [20, 20, 120, 40],
+                ],
+                paintOrders: [0, 1],
+              },
+            },
+          ],
+        };
+      }
+      if (method === "Input.dispatchMouseEvent") return {};
+      if (method === "Runtime.evaluate") {
+        const expression = (params as { expression?: string } | undefined)?.expression ?? "";
+        // Report the button as a `:hover` rule target so a real hover fires.
+        if (expression.includes("document.styleSheets")) {
+          return { result: { value: [{ x: 80, y: 40 }] } };
+        }
+        return { result: { value: [] } };
+      }
+      throw new Error(`unexpected CDP method ${method}`);
+    });
+
+    const res = await handleObserve(
+      sm,
+      { session_id: "aa11", probe_hover: true },
+      {
+        cdp: {
+          send: send as unknown as <T = unknown>(
+            tabId: number,
+            method: string,
+            params?: object,
+          ) => Promise<T>,
+          trackSessionTab: vi.fn(),
+        },
+        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]),
+        },
+      },
+    );
+
+    if ("code" in res) throw new Error(`unexpected error: ${JSON.stringify(res)}`);
+    const firstHover = methodOrder.indexOf("Input.dispatchMouseEvent");
+    expect(firstHover).toBeGreaterThan(-1);
+    expect(methodOrder.lastIndexOf("DOMSnapshot.captureSnapshot")).toBeLessThan(firstHover);
+    expect(methodOrder.lastIndexOf("Accessibility.getFullAXTree")).toBeLessThan(firstHover);
+  });
+
+  it("runs conditional surface probing only when observe opts in", async () => {
    const sm = new SessionManager({ agentWindow: fakeAgentWindow([100]) });
    await sm.start("aa11");
    const root: CdpAxNode = {
@@ -2662,30 +2786,46 @@ describe("handleSnapshot", () => {
      if (method === "Runtime.evaluate") return { result: { value: [] } };
      throw new Error(`unexpected CDP method ${method}`);
    });
-    const res = await handleObserve(
+    const deps = {
+      cdp: {
+        send: send as unknown as <T = unknown>(
+          tabId: number,
+          method: string,
+          params?: object,
+        ) => Promise<T>,
+        trackSessionTab: vi.fn(),
+      },
+      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]),
+      },
+    };
+
+    const withoutProbe = await handleObserve(
      sm,
      { session_id: "aa11", debug_surfaces: true },
-      {
-        cdp: {
-          send: send as unknown as <T = unknown>(
-            tabId: number,
-            method: string,
-            params?: object,
-          ) => Promise<T>,
-          trackSessionTab: vi.fn(),
-        },
-        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]),
-        },
-      },
+      deps,
+    );
+    if ("code" in withoutProbe) {
+      throw new Error(`unexpected error: ${JSON.stringify(withoutProbe)}`);
+    }
+    expect(withoutProbe.hover_probe).toBeUndefined();
+    expect(send).not.toHaveBeenCalledWith(
+      4,
+      "Runtime.evaluate",
+      expect.objectContaining({ returnByValue: true }),
    );

-    if ("code" in res) throw new Error(`unexpected error: ${JSON.stringify(res)}`);
-    expect(res.debug).toEqual({ surface_probes: [] });
+    const withProbe = await handleObserve(
+      sm,
+      { session_id: "aa11", debug_surfaces: true, probe_hover: true },
+      deps,
+    );
+    if ("code" in withProbe) throw new Error(`unexpected error: ${JSON.stringify(withProbe)}`);
+    expect(withProbe.debug).toEqual({ surface_probes: [] });
+    expect(withProbe.hover_probe).toEqual({ performed: true, revealed_content: false });
    expect(send).toHaveBeenCalledWith(
      4,
      "Runtime.evaluate",
@@ -3155,6 +3295,98 @@ describe("handleSnapshot", () => {
    });
  });

+  it("decorates live observations with active controlled content", async () => {
+    const strings = [
+      "html",
+      "body",
+      "button",
+      "div",
+      "#text",
+      "role",
+      "tab",
+      "aria-selected",
+      "true",
+      "aria-controls",
+      "reviews-panel",
+      "id",
+      "static",
+      "auto",
+      "visible",
+      "1",
+      "A detailed review",
+    ];
+    const index = (value: string) => strings.indexOf(value);
+    const style = [index("static"), index("auto"), index("auto"), index("visible"), index("1")];
+    const snapshot = {
+      strings,
+      documents: [
+        {
+          nodes: {
+            parentIndex: [-1, 0, 1, 1, 3],
+            nodeName: [index("html"), index("body"), index("button"), index("div"), index("#text")],
+            backendNodeId: [10, 11, 12, 13, 14],
+            attributes: [
+              [],
+              [],
+              [
+                index("role"),
+                index("tab"),
+                index("aria-selected"),
+                index("true"),
+                index("aria-controls"),
+                index("reviews-panel"),
+              ],
+              [index("id"), index("reviews-panel")],
+              [],
+            ],
+            nodeValue: [-1, -1, -1, -1, index("A detailed review")],
+          },
+          layout: {
+            nodeIndex: [0, 1, 2, 3, 4],
+            styles: [style, style, style, style, style],
+            bounds: [
+              [0, 0, 1000, 800],
+              [0, 0, 1000, 800],
+              [20, 20, 120, 40],
+              [20, 80, 500, 200],
+              [20, 80, 200, 20],
+            ],
+            paintOrders: [0, 0, 1, 1, 1],
+          },
+        },
+      ],
+    };
+    const ax: CdpAxNode[] = [
+      {
+        nodeId: "root",
+        backendDOMNodeId: 11,
+        role: { type: "role", value: "RootWebArea" },
+        childIds: ["reviews"],
+      },
+      {
+        nodeId: "reviews",
+        parentId: "root",
+        backendDOMNodeId: 12,
+        role: { type: "role", value: "tab" },
+        name: { type: "computedString", value: "Reviews" },
+        properties: [
+          { name: "selected", value: { value: true } },
+          { name: "controls", value: { value: "reviews-panel" } },
+        ],
+      },
+    ];
+
+    const result = await captureVomObservation(
+      makeOverlayDeps(ax, snapshot, VP_METRICS).cdp,
+      4,
+      "https://example.com",
+    );
+
+    expect(result.text).toContain('@e1 tab "Reviews"');
+    expect(result.text).toContain("[§ active: Reviews]");
+    expect(result.text).toContain("A detailed review");
+  });
+
  it("does not leak form secrets through the record-safe observation payload", async () => {
    const secrets = {
      email: "user@example.com",
@@ -24,7 +24,7 @@ export interface BorrowResponseMessage {
  allowed: boolean;
 }

-export const CONFIRMATION_TIMEOUT_MS = 5000;
+export const CONFIRMATION_TIMEOUT_MS = 60_000;
 const EXIT_ANIMATION_MS = 150;
 /** Matches BorrowConfirmationOverlay progress ring/bar transition (duration-1000). */
 export const PROGRESS_TRANSITION_MS = 1000;
@@ -480,6 +480,13 @@ export async function requestBorrowConfirmation(
      settle(false);
    }, BACKGROUND_TIMEOUT_MS);

+    // Bring the user window to the front so the overlay is visible even
+    // when the Agent Window has stolen focus. This is fire-and-forget: if
+    // it fails the overlay / OS notification still give the user a path.
+    void windowsApi.update(notificationAnchor.windowId, { focused: true }).catch((err) => {
+      console.debug("[bsk borrow] proactive focus of user window failed", err);
+    });
+
    // Surface the OS notification *before* messaging any candidate so the
    // user has a parallel signal even if every content script is missing.
    // The Allow / Deny buttons let the user authorize explicitly when the
@@ -4,6 +4,7 @@ import type { Transport } from "@/transport/transport";
 import type {
  ClickParams,
  ConsoleParams,
+  DownloadParams,
  EmulateParams,
  EvaluateParams,
  FillParams,
@@ -28,10 +29,12 @@ import type {
  ScreenshotParams,
  SelectParams,
  SnapshotParams,
+  UploadParams,
  WaitForNavigationParams,
 } from "@/transport/types";
 import { isRequestFrame } from "@/transport/types";
 import { handleConsole } from "./console";
+import { handleDownload } from "./download";
 import { type EmulateCdpRunner, handleEmulate } from "./emulate";
 import { handleEvaluate } from "./evaluate";
 import { handleRequestHelp } from "./human-loop";
@@ -51,7 +54,12 @@ import {
  handleScreenshot,
  handleSnapshot,
 } from "./observation";
-import { handleRecordAwait, handleRecordStart, handleRecordStop } from "./record";
+import {
+  handleRecordAwait,
+  handleRecordStart,
+  handleRecordStop,
+  type RecordRuntimeDeps,
+} from "./record";
 import {
  handleSessionStart,
  handleSessionStop,
@@ -74,6 +82,7 @@ import {
  type TabReturnParams,
  type TabSelectParams,
 } from "./tabs";
+import { handleUpload } from "./upload";
 import { handleWaitForNavigation } from "./waits";
 import { handleWindowResize, type WindowResizeParams } from "./window";

@@ -99,6 +108,7 @@ export interface DispatcherDeps {
  transport: Transport;
  sessions: SessionManager;
  cdp?: DispatcherCdpRunner;
+  recording?: RecordRuntimeDeps;
  /**
   * Invoked whenever a dispatched RPC may have changed the live
   * session set (currently `tool.session_start` and
@@ -134,6 +144,7 @@ export class ToolDispatcher {
  private readonly transport: Transport;
  private readonly sessions: SessionManager;
  private readonly cdp?: DispatcherCdpRunner;
+  private readonly recording?: RecordRuntimeDeps;
  private readonly onSessionsChanged?: () => void;
  private readonly onBrowserControlResumed?: (sessionId: string) => void;
  private readonly approveBorrow?: BorrowConfirmationApprover;
@@ -153,6 +164,7 @@ export class ToolDispatcher {
    this.transport = deps.transport;
    this.sessions = deps.sessions;
    this.cdp = deps.cdp;
+    this.recording = deps.recording;
    this.onSessionsChanged = deps.onSessionsChanged;
    this.onBrowserControlResumed = deps.onBrowserControlResumed;
    this.approveBorrow = deps.approveBorrow;
@@ -375,7 +387,11 @@ export class ToolDispatcher {
                ? {
                    cdp: this.cdp,
                    tabsApi: chromeTabsCaptureApi,
-                    conditionalSurfaceProbe: !this.hasHoverLatchForScope(hoverScope),
+                    // Active hover probing is opt-in. A held hover latch still
+                    // suppresses it, because probing would move the cursor off
+                    // the element the caller is deliberately holding.
+                    conditionalSurfaceProbe:
+                      params.probe_hover === true && !this.hasHoverLatchForScope(hoverScope),
                    hoverProbeBypassOverlay: bypassOverlay,
                  }
                : undefined,
@@ -505,6 +521,40 @@ export class ToolDispatcher {
            ),
          signal,
        );
+      case "tool.upload":
+        return this.withHoverReleaseForRequest(
+          req.params as UploadParams,
+          () =>
+            this.cdp
+              ? handleUpload(this.sessions, req.params as UploadParams, {
+                  cdp: this.cdp,
+                  tabsApi: chromeTabsApi,
+                  signal,
+                  bypassOverlay,
+                })
+              : Promise.resolve({
+                  code: "unsupported",
+                  message: "upload requires CDP",
+                } satisfies RpcError),
+          signal,
+        );
+      case "tool.download":
+        return this.withHoverReleaseForRequest(
+          req.params as DownloadParams,
+          () =>
+            this.cdp
+              ? handleDownload(this.sessions, req.params as DownloadParams, {
+                  cdp: this.cdp,
+                  tabsApi: chromeTabsApi,
+                  signal,
+                  bypassOverlay,
+                })
+              : Promise.resolve({
+                  code: "unsupported",
+                  message: "download requires CDP",
+                } satisfies RpcError),
+          signal,
+        );
      case "tool.evaluate":
        return handleEvaluate(
          this.sessions,
@@ -531,44 +581,26 @@ export class ToolDispatcher {
          signal,
        });
      case "tool.record_start":
-        return handleRecordStart(this.sessions, req.params as RecordStartParams, {
-          tabsApi: chromeTabsApi,
-          sendToTab: (tabId, msg) => chrome.tabs.sendMessage(tabId, msg),
-          bypassOverlay: async (tabId, enabled) => {
-            try {
-              await chrome.tabs.sendMessage(tabId, {
-                type: OVERLAY_AUTOMATION_BYPASS,
-                enabled,
-              });
-            } catch {
-              // Content script may be unavailable on restricted pages.
-            }
-          },
-          ...(this.cdp ? { cdp: this.cdp } : {}),
-          signal,
-        });
+        return this.recording
+          ? handleRecordStart(this.sessions, req.params as RecordStartParams, {
+              ...this.recording,
+              signal,
+            })
+          : recordingRuntimeUnavailable();
      case "tool.record_stop":
-        return handleRecordStop(this.sessions, req.params as RecordStopParams, {
-          tabsApi: chromeTabsApi,
-          sendToTab: (tabId, msg) => chrome.tabs.sendMessage(tabId, msg),
-          bypassOverlay: async (tabId, enabled) => {
-            try {
-              await chrome.tabs.sendMessage(tabId, {
-                type: OVERLAY_AUTOMATION_BYPASS,
-                enabled,
-              });
-            } catch {
-              // Content script may be unavailable on restricted pages.
-            }
-          },
-          signal,
-        });
+        return this.recording
+          ? handleRecordStop(this.sessions, req.params as RecordStopParams, {
+              ...this.recording,
+              signal,
+            })
+          : recordingRuntimeUnavailable();
      case "tool.record_await":
-        return handleRecordAwait(this.sessions, req.params as RecordAwaitParams, {
-          tabsApi: chromeTabsApi,
-          sendToTab: (tabId, msg) => chrome.tabs.sendMessage(tabId, msg),
-          signal,
-        });
+        return this.recording
+          ? handleRecordAwait(this.sessions, req.params as RecordAwaitParams, {
+              ...this.recording,
+              signal,
+            })
+          : recordingRuntimeUnavailable();
      default:
        return {
          code: "unknown_method",
@@ -704,6 +736,13 @@ function isRpcError(v: unknown): v is RpcError {
  );
 }

+function recordingRuntimeUnavailable(): RpcError {
+  return {
+    code: "protocol_error",
+    message: "recording runtime is unavailable",
+  };
+}
+
 function sessionIdForBrowserControlMethod(req: RequestFrame): string | null {
  switch (req.method) {
    case "tool.tab_create":
@@ -722,6 +761,8 @@ function sessionIdForBrowserControlMethod(req: RequestFrame): string | null {
    case "tool.fill":
    case "tool.press":
    case "tool.select":
+    case "tool.upload":
+    case "tool.download":
    case "tool.evaluate":
    case "tool.observe":
    case "tool.request_help":
@@ -0,0 +1,375 @@
+// Order-independent coordinator for one browser download. CDP supplies the
+// exact target/frame intent while chrome.downloads supplies the download id
+// and filename routing hook; neither event is assumed to arrive first.
+
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import type { ClickResult, RpcError, TransferEffectState } from "@/transport/types";
+import { transferError } from "./errors";
+import { type CdpRunner, isRpcError } from "./shared";
+
+const CORRELATION_GRACE_MS = 750;
+const UNIQUE_SETTLE_MS = 50;
+const CLEANUP_RECONCILE_MS = 1_000;
+const CLEANUP_POLL_MS = 25;
+const SIZE_POLL_MS = 250;
+
+type DeterminingFilenameListener = (
+  item: chrome.downloads.DownloadItem,
+  suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+) => void | true;
+
+interface ListenerEvent<T> {
+  addListener(listener: T): void;
+  removeListener(listener: T): void;
+}
+
+export interface DownloadsApi {
+  onCreated: ListenerEvent<(item: chrome.downloads.DownloadItem) => void>;
+  onChanged: ListenerEvent<(delta: chrome.downloads.DownloadDelta) => void>;
+  onDeterminingFilename: ListenerEvent<DeterminingFilenameListener>;
+  search(query: chrome.downloads.DownloadQuery): Promise<chrome.downloads.DownloadItem[]>;
+  cancel(downloadId: number): Promise<void>;
+  removeFile(downloadId: number): Promise<void>;
+}
+
+export const chromeDownloadsApi: DownloadsApi = {
+  get onCreated() {
+    return chrome.downloads.onCreated;
+  },
+  get onChanged() {
+    return chrome.downloads.onChanged;
+  },
+  get onDeterminingFilename() {
+    return chrome.downloads.onDeterminingFilename;
+  },
+  search: (query) => chrome.downloads.search(query),
+  cancel: (id) => chrome.downloads.cancel(id),
+  removeFile: (id) => chrome.downloads.removeFile(id),
+};
+
+export interface DownloadCaptureOptions {
+  cdp: CdpRunner;
+  target: CdpTarget;
+  expectedFrameId?: string;
+  downloads: DownloadsApi;
+  browserRelativeDir: string;
+  maxByteSize?: number;
+  timeoutMs: number;
+  signal?: AbortSignal;
+  trigger(): Promise<ClickResult | RpcError>;
+}
+
+export interface DownloadCaptureResult {
+  click: ClickResult;
+  item: chrome.downloads.DownloadItem;
+}
+
+interface DownloadIntent {
+  url: string;
+  suggestedFilename: string;
+  frameId?: string;
+}
+
+interface DownloadCandidate {
+  item: chrome.downloads.DownloadItem;
+  suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void;
+  suggested: boolean;
+  graceTimer: ReturnType<typeof setTimeout>;
+}
+
+function safeBasename(filename: string): string {
+  const basename = filename.split(/[\\/]/).pop()?.trim();
+  return basename && basename !== "." && basename !== ".." ? basename : "download";
+}
+
+function sameTarget(source: { tabId?: number; sessionId?: string }, target: CdpTarget): boolean {
+  return source.tabId === target.tabId && source.sessionId === target.sessionId;
+}
+
+function matchesIntent(item: chrome.downloads.DownloadItem, intent: DownloadIntent): boolean {
+  const urlMatches = item.url === intent.url || item.finalUrl === intent.url;
+  return urlMatches && safeBasename(item.filename) === safeBasename(intent.suggestedFilename);
+}
+
+function knownSize(item: chrome.downloads.DownloadItem): number | undefined {
+  if (item.fileSize >= 0) return item.fileSize;
+  if (item.totalBytes >= 0) return item.totalBytes;
+  return undefined;
+}
+
+function captureError(
+  message: string,
+  effectState: TransferEffectState,
+  phase: string,
+  cleanupFailed = false,
+): RpcError {
+  return transferError("cdp_failed", "download_capture_failed", message, {
+    effectState,
+    phase,
+    ...(cleanupFailed ? { cleanupState: "failed" } : {}),
+  });
+}
+
+async function cleanupClaimedDownload(downloads: DownloadsApi, downloadId: number): Promise<void> {
+  const lookup = async () => (await downloads.search({ id: downloadId }))[0];
+  let item = await lookup();
+  if (!item || item.state === "interrupted") return;
+  if (item.state === "complete") {
+    await downloads.removeFile(downloadId);
+    return;
+  }
+
+  let cancelError: unknown;
+  try {
+    await downloads.cancel(downloadId);
+  } catch (error) {
+    cancelError = error;
+  }
+
+  const deadline = Date.now() + CLEANUP_RECONCILE_MS;
+  while (true) {
+    item = await lookup();
+    if (!item || item.state === "interrupted") return;
+    if (item.state === "complete") {
+      await downloads.removeFile(downloadId);
+      return;
+    }
+    if (Date.now() >= deadline) {
+      if (cancelError instanceof Error) throw cancelError;
+      throw new Error("download remained in progress after cancellation");
+    }
+    await new Promise((resolve) =>
+      setTimeout(resolve, Math.min(CLEANUP_POLL_MS, Math.max(1, deadline - Date.now()))),
+    );
+  }
+}
+
+export async function captureBrowserDownload(
+  options: DownloadCaptureOptions,
+): Promise<DownloadCaptureResult | RpcError> {
+  let click: ClickResult | undefined;
+  let intent: DownloadIntent | undefined;
+  let capturedId: number | undefined;
+  let settled = false;
+  let succeeded = false;
+  let failureResult: RpcError | undefined;
+  let uniquenessTimer: ReturnType<typeof setTimeout> | undefined;
+  let operationTimer: ReturnType<typeof setTimeout> | undefined;
+  let sizePoll: ReturnType<typeof setInterval> | undefined;
+  const candidates = new Map<number, DownloadCandidate>();
+  const createdItems = new Map<number, chrome.downloads.DownloadItem>();
+
+  let resolveCompletion!: (item: chrome.downloads.DownloadItem) => void;
+  let rejectCompletion!: (error: Error) => void;
+  const completion = new Promise<chrome.downloads.DownloadItem>((resolve, reject) => {
+    resolveCompletion = resolve;
+    rejectCompletion = reject;
+  });
+  const fail = (error: Error) => {
+    if (settled) return;
+    settled = true;
+    rejectCompletion(error);
+  };
+  const complete = (item: chrome.downloads.DownloadItem) => {
+    if (settled) return;
+    const size = knownSize(item);
+    if (size !== undefined && options.maxByteSize !== undefined && size > options.maxByteSize) {
+      fail(new Error(`download exceeds transfer limit ${options.maxByteSize}`));
+      return;
+    }
+    settled = true;
+    resolveCompletion(item);
+  };
+  const suggestDefault = (candidate: DownloadCandidate) => {
+    if (candidate.suggested) return;
+    candidate.suggested = true;
+    candidate.suggest();
+  };
+  const matchingCandidates = (): DownloadCandidate[] => {
+    const currentIntent = intent;
+    return currentIntent
+      ? [...candidates.values()].filter(
+          (candidate) => !candidate.suggested && matchesIntent(candidate.item, currentIntent),
+        )
+      : [];
+  };
+
+  const claimUnique = () => {
+    uniquenessTimer = undefined;
+    if (settled || capturedId !== undefined || !intent) return;
+    const matches = matchingCandidates();
+    if (matches.length !== 1) {
+      if (matches.length > 1) {
+        for (const candidate of matches) suggestDefault(candidate);
+        fail(new Error("download attribution is ambiguous"));
+      }
+      return;
+    }
+    const candidate = matches[0];
+    candidate.suggested = true;
+    clearTimeout(candidate.graceTimer);
+    capturedId = candidate.item.id;
+    candidate.suggest({
+      filename: `${options.browserRelativeDir}/${safeBasename(intent.suggestedFilename)}`,
+      conflictAction: "overwrite",
+    });
+    const size = knownSize(candidate.item);
+    if (size !== undefined && options.maxByteSize !== undefined && size > options.maxByteSize) {
+      fail(new Error(`download exceeds transfer limit ${options.maxByteSize}`));
+      return;
+    }
+    const created = createdItems.get(candidate.item.id);
+    if (created?.state === "interrupted") {
+      fail(new Error(created.error ?? "download interrupted"));
+    } else if (created?.state === "complete") {
+      complete(created);
+    }
+  };
+  const reconcile = () => {
+    if (settled || capturedId !== undefined || !intent) return;
+    const matches = matchingCandidates();
+    if (matches.length > 1) {
+      for (const candidate of matches) suggestDefault(candidate);
+      fail(new Error("download attribution is ambiguous"));
+      return;
+    }
+    if (matches.length === 1 && !uniquenessTimer) {
+      uniquenessTimer = setTimeout(claimUnique, UNIQUE_SETTLE_MS);
+    }
+  };
+
+  const determiningListener: DeterminingFilenameListener = (item, suggest) => {
+    const candidate: DownloadCandidate = {
+      item,
+      suggest,
+      suggested: false,
+      graceTimer: setTimeout(() => {
+        suggestDefault(candidate);
+        candidates.delete(item.id);
+        if (intent && matchesIntent(item, intent) && capturedId === undefined) {
+          fail(new Error("download correlation grace elapsed before unique attribution"));
+        }
+      }, CORRELATION_GRACE_MS),
+    };
+    candidates.set(item.id, candidate);
+    reconcile();
+    return true;
+  };
+  const createdListener = (item: chrome.downloads.DownloadItem) => {
+    createdItems.set(item.id, item);
+    if (capturedId !== item.id) return;
+    if (item.state === "interrupted") {
+      fail(new Error(item.error ?? "download interrupted"));
+    } else if (item.state === "complete") {
+      complete(item);
+    }
+  };
+  const changedListener = async (delta: chrome.downloads.DownloadDelta) => {
+    if (capturedId === undefined || delta.id !== capturedId || settled) return;
+    if (delta.state?.current === "interrupted" || delta.error?.current) {
+      fail(new Error(delta.error?.current ?? "download interrupted"));
+      return;
+    }
+    if (delta.state?.current === "complete") {
+      try {
+        const [item] = await options.downloads.search({ id: delta.id });
+        if (item) complete(item);
+        else fail(new Error("completed download disappeared"));
+      } catch (err) {
+        fail(err instanceof Error ? err : new Error(String(err)));
+      }
+    }
+  };
+  const onAbort = () => fail(new DOMException("aborted", "AbortError"));
+  const cdpSubscription = options.cdp.onEvent?.((source, method, raw) => {
+    if (method !== "Page.downloadWillBegin" || !sameTarget(source, options.target)) return;
+    const event = raw as { url?: unknown; suggestedFilename?: unknown; frameId?: unknown };
+    if (typeof event.url !== "string" || typeof event.suggestedFilename !== "string") return;
+    if (options.expectedFrameId && event.frameId !== options.expectedFrameId) {
+      fail(new Error("download originated from a different frame"));
+      return;
+    }
+    if (intent) {
+      fail(new Error("download trigger produced more than one browser download intent"));
+      return;
+    }
+    intent = {
+      url: event.url,
+      suggestedFilename: event.suggestedFilename,
+      ...(typeof event.frameId === "string" ? { frameId: event.frameId } : {}),
+    };
+    reconcile();
+  });
+  if (!cdpSubscription) {
+    return captureError("CDP download intent subscription unavailable", "none", "arm");
+  }
+
+  options.downloads.onDeterminingFilename.addListener(determiningListener);
+  options.downloads.onCreated.addListener(createdListener);
+  options.downloads.onChanged.addListener(changedListener);
+  options.signal?.addEventListener("abort", onAbort, { once: true });
+  operationTimer = setTimeout(
+    () => fail(new Error("download did not complete before timeout")),
+    options.timeoutMs,
+  );
+  sizePoll = setInterval(() => {
+    if (capturedId === undefined || settled || options.maxByteSize === undefined) return;
+    void options.downloads
+      .search({ id: capturedId })
+      .then(([item]) => {
+        if (!item || settled) return;
+        if (item.bytesReceived > (options.maxByteSize as number)) {
+          fail(new Error(`download exceeds transfer limit ${options.maxByteSize}`));
+        }
+      })
+      .catch((err) => fail(err instanceof Error ? err : new Error(String(err))));
+  }, SIZE_POLL_MS);
+
+  try {
+    const triggered = await options.trigger();
+    if (isRpcError(triggered)) {
+      void completion.catch(() => undefined);
+      const effect: TransferEffectState =
+        capturedId !== undefined ? "committed" : intent ? "unknown" : "none";
+      failureResult = {
+        ...triggered,
+        data: { ...triggered.data, effect_state: effect, phase: "trigger" },
+      };
+      return failureResult;
+    }
+    click = triggered;
+    const item = await completion;
+    succeeded = true;
+    return { click, item };
+  } catch (err) {
+    const effect: TransferEffectState =
+      capturedId !== undefined ? "committed" : click ? "unknown" : "none";
+    failureResult = captureError(
+      err instanceof Error ? err.message : String(err),
+      effect,
+      capturedId !== undefined ? "download" : "attribution",
+    );
+    return failureResult;
+  } finally {
+    settled = true;
+    if (operationTimer) clearTimeout(operationTimer);
+    if (uniquenessTimer) clearTimeout(uniquenessTimer);
+    if (sizePoll) clearInterval(sizePoll);
+    options.signal?.removeEventListener("abort", onAbort);
+    options.downloads.onDeterminingFilename.removeListener(determiningListener);
+    options.downloads.onCreated.removeListener(createdListener);
+    options.downloads.onChanged.removeListener(changedListener);
+    cdpSubscription.dispose();
+    for (const candidate of candidates.values()) {
+      clearTimeout(candidate.graceTimer);
+      if (candidate.item.id !== capturedId) suggestDefault(candidate);
+    }
+    if (!succeeded && capturedId !== undefined) {
+      try {
+        await cleanupClaimedDownload(options.downloads, capturedId);
+      } catch {
+        if (failureResult?.data) failureResult.data.cleanup_state = "failed";
+      }
+    }
+  }
+}
@@ -0,0 +1,64 @@
+// Download orchestration: validate session/tab ownership, then delegate one
+// browser-global chrome.downloads transaction to download-capture.ts.
+
+import type { SessionManager } from "@/session-manager/manager";
+import type { DownloadParams, DownloadResult, RpcError } from "@/transport/types";
+import { captureBrowserDownload, chromeDownloadsApi, type DownloadsApi } from "./download-capture";
+import { clickResolvedTarget, type InteractionDeps, resolveActionTarget } from "./interaction";
+import { enforceAgentWindow, isRpcError, lookupSession, resolveTargetTab } from "./shared";
+
+let downloadActive = false;
+
+export type { DownloadsApi } from "./download-capture";
+
+export interface DownloadDeps extends InteractionDeps {
+  downloads?: DownloadsApi;
+}
+
+export async function handleDownload(
+  manager: SessionManager,
+  params: DownloadParams,
+  deps: DownloadDeps,
+): Promise<DownloadResult | RpcError> {
+  if (downloadActive) return { code: "invalid_params", message: "another bsk download is active" };
+  downloadActive = true;
+  try {
+    const ctx = lookupSession(manager, params, "download");
+    if (isRpcError(ctx)) return ctx;
+    const target = await resolveTargetTab(manager, ctx, params.tab_id, deps.tabsApi);
+    if (isRpcError(target)) return target;
+    const denied = enforceAgentWindow(ctx, target, "download");
+    if (denied) return denied;
+    if (!params.browser_relative_dir) {
+      return { code: "invalid_params", message: "download requires a daemon capability directory" };
+    }
+    const address = await resolveActionTarget(deps.cdp, ctx, target, params, "download");
+    if (isRpcError(address)) return address;
+
+    const capture = await captureBrowserDownload({
+      cdp: deps.cdp,
+      target: address.cdpTarget,
+      downloads: deps.downloads ?? chromeDownloadsApi,
+      browserRelativeDir: params.browser_relative_dir,
+      maxByteSize: params.max_byte_size,
+      timeoutMs: params.timeout_ms ?? 120_000,
+      signal: deps.signal,
+      expectedFrameId: address.frameId,
+      trigger: () => clickResolvedTarget(ctx, address, {}, deps),
+    });
+    if (isRpcError(capture)) return capture;
+    const { click, item } = capture;
+    return {
+      tab_id: target.tabId,
+      used_ref: click.used_ref,
+      used_selector: click.used_selector,
+      suggested_filename: item.filename.split(/[\\/]/).pop() ?? "download",
+      byte_size: item.fileSize >= 0 ? item.fileSize : item.totalBytes,
+      mime: item.mime || undefined,
+      danger: item.danger,
+      browser_path: item.filename,
+    };
+  } finally {
+    downloadActive = false;
+  }
+}
@@ -2,10 +2,23 @@
 // rendering. Extension handlers attach reasons here; human-facing copy
 // lives in bsk-cli `render_error.rs`.

-import type { ErrorCode, RpcError, RpcErrorData, RpcErrorReason } from "@/transport/types";
+import type {
+  ErrorCode,
+  RpcError,
+  RpcErrorData,
+  RpcErrorReason,
+  TransferCleanupState,
+  TransferEffectState,
+} from "@/transport/types";

 export type { RpcErrorData, RpcErrorReason };

+export interface TransferErrorOptions {
+  effectState: TransferEffectState;
+  phase: string;
+  cleanupState?: TransferCleanupState;
+}
+
 export function rpcError(
  code: ErrorCode,
  reason: RpcErrorReason,
@@ -15,3 +28,16 @@ export function rpcError(
  const data: RpcErrorData = { reason, ...extra };
  return { code, message, data };
 }
+
+export function transferError(
+  code: ErrorCode,
+  reason: RpcErrorReason,
+  message: string,
+  options: TransferErrorOptions,
+): RpcError {
+  return rpcError(code, reason, message, {
+    effect_state: options.effectState,
+    phase: options.phase,
+    ...(options.cleanupState ? { cleanup_state: options.cleanupState } : {}),
+  });
+}
@@ -0,0 +1,528 @@
+// One upload transaction with an explicit browser-side commit boundary.
+// Chrome interception prevents a native chooser from escaping automation;
+// chooser events and a frame-scoped DOM probe are independent input-location
+// signals, so event delivery is not required for standard file inputs.
+
+import type { ClickResult, RpcError, TransferEffectState } from "@/transport/types";
+import { transferError } from "./errors";
+import type { ResolvedActionTarget } from "./interaction";
+import { type CdpRunner, isRpcError, sendToCdpTarget } from "./shared";
+
+const CLEANUP_TIMEOUT_MS = 1_000;
+const DETACH_TIMEOUT_MS = 500;
+const ACTIVATION_GRACE_MS = 1_000;
+const PROBE_INTERVAL_MS = 20;
+
+type UploadPhase =
+  | "arm_interception"
+  | "arm_input_probe"
+  | "trigger"
+  | "resolve_input"
+  | "set_files"
+  | "cleanup";
+
+interface RuntimeReply {
+  result?: { value?: unknown; objectId?: string };
+  exceptionDetails?: { text?: string; exception?: { description?: string } };
+}
+
+interface ChooserEvent {
+  frameId?: string;
+  backendNodeId?: number;
+  mode?: "selectSingle" | "selectMultiple";
+}
+
+export interface FileInputTransactionOptions {
+  cdp: CdpRunner;
+  actionTarget: ResolvedActionTarget;
+  files: string[];
+  timeoutMs: number;
+  signal?: AbortSignal;
+  trigger(): Promise<ClickResult | RpcError>;
+}
+
+export interface FileInputTransactionResult {
+  click: ClickResult;
+  multiple: boolean;
+}
+
+class BoundedWaitError extends Error {
+  constructor(
+    readonly kind: "timeout" | "aborted",
+    message: string,
+  ) {
+    super(message);
+  }
+}
+
+function remainingMs(deadline: number): number {
+  return Math.max(0, deadline - Date.now());
+}
+
+async function waitBounded<T>(
+  operation: () => Promise<T>,
+  deadline: number,
+  signal: AbortSignal | undefined,
+  timeoutMessage: string,
+): Promise<T> {
+  const remaining = remainingMs(deadline);
+  if (signal?.aborted) throw new BoundedWaitError("aborted", "upload transaction aborted");
+  if (remaining === 0) throw new BoundedWaitError("timeout", timeoutMessage);
+
+  let timer: ReturnType<typeof setTimeout> | undefined;
+  let onAbort: (() => void) | undefined;
+  const boundary = new Promise<never>((_resolve, reject) => {
+    timer = setTimeout(() => reject(new BoundedWaitError("timeout", timeoutMessage)), remaining);
+    if (signal) {
+      onAbort = () => reject(new BoundedWaitError("aborted", "upload transaction aborted"));
+      signal.addEventListener("abort", onAbort, { once: true });
+    }
+  });
+  try {
+    const work = Promise.resolve().then(() => {
+      if (signal?.aborted) throw new BoundedWaitError("aborted", "upload transaction aborted");
+      if (remainingMs(deadline) === 0) throw new BoundedWaitError("timeout", timeoutMessage);
+      return operation();
+    });
+    return await Promise.race([work, boundary]);
+  } finally {
+    if (timer) clearTimeout(timer);
+    if (signal && onAbort) signal.removeEventListener("abort", onAbort);
+  }
+}
+
+function runtimeError(reply: RuntimeReply, fallback: string): Error | null {
+  if (!reply.exceptionDetails) return null;
+  return new Error(
+    reply.exceptionDetails.exception?.description ?? reply.exceptionDetails.text ?? fallback,
+  );
+}
+
+function transferFailure(
+  code: RpcError["code"],
+  reason: "file_input_probe_failed" | "file_input_not_activated" | "set_file_input_failed",
+  message: string,
+  effectState: TransferEffectState,
+  phase: UploadPhase,
+): RpcError {
+  return transferError(code, reason, message, { effectState, phase });
+}
+
+function enrichFailure(
+  error: RpcError,
+  effectState: TransferEffectState,
+  phase: UploadPhase,
+): RpcError {
+  return {
+    ...error,
+    data: { ...error.data, effect_state: effectState, phase },
+  };
+}
+
+function sameTarget(
+  source: { tabId?: number; sessionId?: string },
+  target: { tabId: number; sessionId?: string },
+): boolean {
+  return source.tabId === target.tabId && source.sessionId === target.sessionId;
+}
+
+async function delay(ms: number, signal?: AbortSignal): Promise<void> {
+  await waitBounded(
+    () => new Promise((resolve) => setTimeout(resolve, ms)),
+    Date.now() + ms + 1,
+    signal,
+    "upload activation probe timed out",
+  );
+}
+
+function waitErrorCode(error: unknown): RpcError["code"] {
+  if (!(error instanceof BoundedWaitError)) return "cdp_failed";
+  return error.kind === "aborted" ? "cancelled" : "timeout";
+}
+
+async function callOnTrigger<T = RuntimeReply>(
+  options: FileInputTransactionOptions,
+  objectId: string,
+  functionDeclaration: string,
+  args: unknown[],
+  returnByValue: boolean,
+): Promise<T> {
+  return sendToCdpTarget<T>(options.cdp, options.actionTarget.cdpTarget, "Runtime.callFunctionOn", {
+    objectId,
+    functionDeclaration,
+    arguments: args.map((value) => ({ value })),
+    returnByValue,
+    awaitPromise: false,
+  });
+}
+
+export async function uploadThroughActivatedFileInput(
+  options: FileInputTransactionOptions,
+): Promise<FileInputTransactionResult | RpcError> {
+  const deadline = Date.now() + options.timeoutMs;
+  const target = options.actionTarget.cdpTarget;
+  const objectGroup = `bsk-upload-${crypto.randomUUID()}`;
+  const stateKey = `__bskUpload_${crypto.randomUUID().replaceAll("-", "")}`;
+  const chooserEvents: ChooserEvent[] = [];
+  let interceptionState: "not_started" | "possibly_active" | "active" = "not_started";
+  let probeState: "not_started" | "possibly_active" | "active" = "not_started";
+  let triggerObjectId: string | undefined;
+  let outcome: FileInputTransactionResult | RpcError = transferFailure(
+    "protocol_error",
+    "file_input_probe_failed",
+    "upload transaction ended without an outcome",
+    "none",
+    "cleanup",
+  );
+
+  const chooserSubscription = options.cdp.onEvent?.((source, method, raw) => {
+    if (method !== "Page.fileChooserOpened" || !sameTarget(source, target)) return;
+    const event = raw as ChooserEvent;
+    chooserEvents.push(event);
+  });
+
+  try {
+    try {
+      interceptionState = "possibly_active";
+      await waitBounded(
+        () =>
+          sendToCdpTarget(options.cdp, target, "Page.setInterceptFileChooserDialog", {
+            enabled: true,
+          }),
+        deadline,
+        options.signal,
+        "arming native file chooser interception timed out",
+      );
+      interceptionState = "active";
+    } catch (err) {
+      outcome = transferFailure(
+        waitErrorCode(err),
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "arm_interception",
+      );
+      return outcome;
+    }
+
+    try {
+      const resolved = await waitBounded(
+        () =>
+          sendToCdpTarget<{ object?: { objectId?: string } }>(
+            options.cdp,
+            target,
+            "DOM.resolveNode",
+            {
+              backendNodeId: options.actionTarget.backendNodeId,
+              objectGroup,
+            },
+          ),
+        deadline,
+        options.signal,
+        "resolving upload trigger timed out",
+      );
+      triggerObjectId = resolved.object?.objectId;
+      if (!triggerObjectId) throw new Error("DOM.resolveNode returned no trigger objectId");
+
+      probeState = "possibly_active";
+      const armed = await waitBounded(
+        () =>
+          callOnTrigger<RuntimeReply>(
+            options,
+            triggerObjectId as string,
+            `function(key) {
+            const doc = this.ownerDocument;
+            const owner = doc.defaultView;
+            if (!owner) return false;
+            const state = { inputs: [], listener: null };
+            Object.defineProperty(owner, key, { value: state, configurable: true });
+            state.listener = event => {
+              const path = typeof event.composedPath === "function" ? event.composedPath() : [];
+              const candidate = path[0] || event.target;
+              if (candidate && candidate.nodeType === 1 &&
+                  candidate.localName === "input" && candidate.type === "file") {
+                if (!state.inputs.includes(candidate)) state.inputs.push(candidate);
+                event.preventDefault();
+              }
+            };
+            doc.addEventListener("click", state.listener, true);
+            return true;
+          }`,
+            [stateKey],
+            true,
+          ),
+        deadline,
+        options.signal,
+        "arming frame-scoped file input probe timed out",
+      );
+      const armError = runtimeError(armed, "failed to arm file input probe");
+      if (armError || armed.result?.value !== true) {
+        throw armError ?? new Error("file input probe did not arm");
+      }
+      probeState = "active";
+    } catch (err) {
+      outcome = transferFailure(
+        waitErrorCode(err),
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "arm_input_probe",
+      );
+      return outcome;
+    }
+
+    let click: ClickResult | RpcError;
+    try {
+      click = await waitBounded(
+        options.trigger,
+        deadline,
+        options.signal,
+        "upload trigger timed out",
+      );
+    } catch (err) {
+      outcome = transferFailure(
+        waitErrorCode(err),
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "trigger",
+      );
+      return outcome;
+    }
+    if (isRpcError(click)) {
+      outcome = enrichFailure(click, "none", "trigger");
+      return outcome;
+    }
+
+    try {
+      const activationDeadline = Math.min(deadline, Date.now() + ACTIVATION_GRACE_MS);
+      let summary: { count: number; multiple: boolean } = { count: 0, multiple: false };
+      while (Date.now() < activationDeadline) {
+        if (chooserEvents.length > 0) break;
+        const reply = await waitBounded(
+          () =>
+            callOnTrigger<RuntimeReply>(
+              options,
+              triggerObjectId as string,
+              `function(key) {
+            const state = this.ownerDocument.defaultView?.[key];
+            return state
+              ? { count: state.inputs.length, multiple: state.inputs[0]?.multiple === true }
+              : { count: 0, multiple: false };
+          }`,
+              [stateKey],
+              true,
+            ),
+          activationDeadline,
+          options.signal,
+          "inspecting activated file input timed out",
+        );
+        const summaryError = runtimeError(reply, "failed to inspect activated file input");
+        if (summaryError) throw summaryError;
+        const value = reply.result?.value as { count?: unknown; multiple?: unknown } | undefined;
+        summary = {
+          count: typeof value?.count === "number" ? value.count : 0,
+          multiple: value?.multiple === true,
+        };
+        if (summary.count > 0) break;
+        await delay(Math.min(PROBE_INTERVAL_MS, remainingMs(activationDeadline)), options.signal);
+      }
+
+      if (chooserEvents.length > 1) {
+        outcome = transferFailure(
+          "unsupported",
+          "file_input_not_activated",
+          "upload trigger activated more than one file chooser",
+          "none",
+          "resolve_input",
+        );
+        return outcome;
+      }
+
+      const chooser = chooserEvents[0];
+      let backendNodeId: number | undefined;
+      let multiple = summary.multiple;
+      if (chooser) {
+        if (options.actionTarget.frameId && chooser.frameId !== options.actionTarget.frameId) {
+          outcome = transferFailure(
+            "unsupported",
+            "file_input_not_activated",
+            "upload trigger activated a file chooser in a different frame",
+            "none",
+            "resolve_input",
+          );
+          return outcome;
+        }
+        if (typeof chooser.backendNodeId !== "number") {
+          outcome = transferFailure(
+            "unsupported",
+            "file_input_not_activated",
+            "upload trigger invoked a non-input file picker",
+            "none",
+            "resolve_input",
+          );
+          return outcome;
+        }
+        backendNodeId = chooser.backendNodeId;
+        multiple = chooser.mode === "selectMultiple";
+      } else {
+        if (summary.count !== 1) {
+          outcome = transferFailure(
+            "unsupported",
+            "file_input_not_activated",
+            summary.count === 0
+              ? "upload trigger did not activate an input[type=file]"
+              : "upload trigger activated more than one input[type=file]",
+            "none",
+            "resolve_input",
+          );
+          return outcome;
+        }
+        const input = await waitBounded(
+          () =>
+            callOnTrigger<RuntimeReply>(
+              options,
+              triggerObjectId as string,
+              `function(key) { return this.ownerDocument.defaultView?.[key]?.inputs[0]; }`,
+              [stateKey],
+              false,
+            ),
+          deadline,
+          options.signal,
+          "resolving activated file input timed out",
+        );
+        const inputError = runtimeError(input, "failed to resolve activated file input object");
+        if (inputError) throw inputError;
+        if (!input.result?.objectId) throw new Error("activated file input returned no objectId");
+        const described = await waitBounded(
+          () =>
+            sendToCdpTarget<{ node?: { backendNodeId?: number } }>(
+              options.cdp,
+              target,
+              "DOM.describeNode",
+              { objectId: input.result?.objectId },
+            ),
+          deadline,
+          options.signal,
+          "describing activated file input timed out",
+        );
+        backendNodeId = described.node?.backendNodeId;
+        if (typeof backendNodeId !== "number") {
+          throw new Error("DOM.describeNode returned no file input backendNodeId");
+        }
+      }
+
+      if (!multiple && options.files.length !== 1) {
+        outcome = enrichFailure(
+          { code: "invalid_params", message: "file input accepts exactly one file" },
+          "none",
+          "resolve_input",
+        );
+        return outcome;
+      }
+
+      try {
+        await waitBounded(
+          () =>
+            sendToCdpTarget(options.cdp, target, "DOM.setFileInputFiles", {
+              files: options.files,
+              backendNodeId,
+            }),
+          deadline,
+          options.signal,
+          "setting file input files timed out",
+        );
+      } catch (err) {
+        outcome = transferFailure(
+          waitErrorCode(err),
+          "set_file_input_failed",
+          err instanceof Error ? err.message : String(err),
+          "unknown",
+          "set_files",
+        );
+        return outcome;
+      }
+      outcome = { click, multiple };
+      return outcome;
+    } catch (err) {
+      outcome = transferFailure(
+        waitErrorCode(err),
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "resolve_input",
+      );
+      return outcome;
+    }
+  } finally {
+    chooserSubscription?.dispose();
+    const cleanupDeadline = Date.now() + CLEANUP_TIMEOUT_MS;
+    const cleanupTasks: Promise<boolean>[] = [];
+    const cleanup = async (operation: () => Promise<unknown>, message: string) => {
+      try {
+        await waitBounded(operation, cleanupDeadline, undefined, message);
+        return true;
+      } catch {
+        return false;
+      }
+    };
+    if (probeState !== "not_started" && triggerObjectId) {
+      cleanupTasks.push(
+        cleanup(
+          () =>
+            callOnTrigger(
+              options,
+              triggerObjectId as string,
+              `function(key) {
+              const owner = this.ownerDocument.defaultView;
+              const state = owner?.[key];
+              if (state?.listener) this.ownerDocument.removeEventListener("click", state.listener, true);
+              if (owner) delete owner[key];
+            }`,
+              [stateKey],
+              true,
+            ),
+          "cleaning file input probe timed out",
+        ),
+      );
+    }
+    if (interceptionState !== "not_started") {
+      cleanupTasks.push(
+        cleanup(
+          () =>
+            sendToCdpTarget(options.cdp, target, "Page.setInterceptFileChooserDialog", {
+              enabled: false,
+              cancel: true,
+            }),
+          "disabling file chooser interception timed out",
+        ),
+      );
+    }
+    let cleanupFailed = (await Promise.all(cleanupTasks)).some((completed) => !completed);
+    if (!cleanupFailed) {
+      cleanupFailed = !(await cleanup(
+        () => sendToCdpTarget(options.cdp, target, "Runtime.releaseObjectGroup", { objectGroup }),
+        "releasing upload object group timed out",
+      ));
+    }
+
+    const effect = isRpcError(outcome)
+      ? (outcome.data?.effect_state as TransferEffectState | undefined)
+      : "committed";
+    if (effect === "unknown" || cleanupFailed) {
+      try {
+        await waitBounded(
+          () => options.cdp.detach?.(target.tabId) ?? Promise.resolve(),
+          Date.now() + DETACH_TIMEOUT_MS,
+          undefined,
+          "detaching upload target timed out",
+        );
+      } catch {
+        cleanupFailed = true;
+      }
+    }
+    if (cleanupFailed && isRpcError(outcome)) {
+      outcome.data = { ...outcome.data, cleanup_state: "failed" };
+    }
+  }
+}
@@ -40,6 +40,7 @@ import {
  enforceAgentWindow,
  isRpcError,
  lookupSession,
+  type ResolvedTargetTab,
  resolveTargetTab,
 } from "./shared";
 import { resolveSnapshotRef } from "./snapshot-ref";
@@ -56,6 +57,15 @@ export interface InteractionDeps {
  keepOverlayBypassAfterHover?: boolean;
 }

+export interface ResolvedActionTarget {
+  tab: ResolvedTargetTab;
+  backendNodeId: number;
+  cdpTarget: CdpTarget;
+  frameId?: string;
+  usedRef?: string;
+  usedSelector?: string;
+}
+
 const DEFAULT_TIMEOUT_MS = 30_000;
 const DEFAULT_HOVER_SETTLE_MS = 200;

@@ -128,7 +138,7 @@ async function wait(ms: number, signal?: AbortSignal): Promise<void> {
 * `RpcError` if the caller supplied neither (or both), or if neither
 * lookup matched.
 */
-async function resolveBackendNode(
+export async function resolveBackendNode(
  cdp: CdpRunner,
  ctx: SessionContext,
  target: { tabId: number },
@@ -215,6 +225,17 @@ async function resolveBackendNode(
  }
 }

+export async function resolveActionTarget(
+  cdp: CdpRunner,
+  ctx: SessionContext,
+  target: ResolvedTargetTab,
+  params: { ref?: string; selector?: string },
+  toolName: string,
+): Promise<ResolvedActionTarget | RpcError> {
+  const node = await resolveBackendNode(cdp, ctx, target, params, toolName);
+  return isRpcError(node) ? node : { tab: target, ...node };
+}
+
 // ---------------------------------------------------------------------------
 // tool.click
 // ---------------------------------------------------------------------------
@@ -233,10 +254,19 @@ export async function handleClick(
  if (isRpcError(target)) return target;
  const denied = enforceAgentWindow(ctx, target, "click");
  if (denied) return denied;
-  const dialogCursor = markDialogCursor(deps.cdp, target.tabId);
+  const resolved = await resolveActionTarget(deps.cdp, ctx, target, params, "click");
+  if (isRpcError(resolved)) return resolved;
+  return clickResolvedTarget(ctx, resolved, params, deps);
+}

-  const node = await resolveBackendNode(deps.cdp, ctx, target, params, "click");
-  if (isRpcError(node)) return node;
+export async function clickResolvedTarget(
+  ctx: SessionContext,
+  resolved: ResolvedActionTarget,
+  params: Pick<ClickParams, "button" | "click_count" | "modifiers">,
+  deps: InteractionDeps,
+): Promise<ClickResult | RpcError> {
+  const { tab: target } = resolved;
+  const dialogCursor = markDialogCursor(deps.cdp, target.tabId);

  if (throwIfAborted(deps.signal)) {
    return { code: "cancelled", message: "click aborted" };
@@ -247,9 +277,9 @@ export async function handleClick(
    deps.cdp,
    target.tabId,
    {
-      target: node.cdpTarget,
-      backendNodeId: node.backendNodeId,
-      ...(node.frameId ? { frameId: node.frameId } : {}),
+      target: resolved.cdpTarget,
+      backendNodeId: resolved.backendNodeId,
+      ...(resolved.frameId ? { frameId: resolved.frameId } : {}),
    },
    { scrollIntoView: true },
  );
@@ -337,8 +367,8 @@ export async function handleClick(

  return attachDialogs(deps.cdp, target.tabId, dialogCursor, {
    tab_id: target.tabId,
-    used_ref: node.usedRef,
-    used_selector: node.usedSelector,
+    used_ref: resolved.usedRef,
+    used_selector: resolved.usedSelector,
    x: centre.x,
    y: centre.y,
  });
@@ -15,22 +15,37 @@ import {
  type RecordQueryResponse,
  type RecordStartAck,
  type RecordStartMessage,
+  type RecordStepAck,
  type RecordStopMessage,
 } from "@/lib/record-bridge";
-import { appendRecordedPayload, observeRecordedNavigation } from "@/lib/recording-step-buffer";
-import { reduceTraceSteps, resolveTraceStartUrl } from "@/lib/trace-reducer";
+import {
+  type RecordFrameCoordinator,
+  type RecordingCaptureScope,
+  recordFrameCoordinator,
+} from "@/lib/recording/frame-coordinator";
+import { RecordingObservationRuntime } from "@/lib/recording/recording-runtime";
+import {
+  appendRecordedPayload,
+  observeRecordedNavigation,
+  type RecordingStepBuffer,
+} from "@/lib/recording/step-buffer";
+import { RecordingTabCoordinator, type TabActivation } from "@/lib/recording/tab-coordinator";
+import { buildTraceV2 } from "@/lib/recording/trace-reducer-v2";
+import type { RecordingDraftStep } from "@/lib/recording/types";
 import type { SessionManager } from "@/session-manager/manager";
+import { EXTENSION_VERSION } from "@/transport/handshake";
 import type {
-  DraftTraceStep,
  RecordAwaitParams,
  RecordAwaitResult,
+  RecordedTrace,
  RecordStartParams,
  RecordStartResult,
  RecordStopParams,
  RecordStopResult,
  RpcError,
-  Trace,
+  StopReason,
 } from "@/transport/types";
+import { TRACE_VERSION_V3 } from "@/transport/types";
 import { handleNavigate } from "./navigation";
 import {
  type CdpRunner,
@@ -43,21 +58,46 @@ import {

 interface ActiveRecording {
  requestId: string;
-  tabId: number;
+  tabs: RecordingTabCoordinator;
  agentWindowId: number;
  startUrl?: string;
  purpose?: string;
-  steps: DraftTraceStep[];
+  steps: RecordingDraftStep[];
  startedAt: string;
  startedAtMs: number;
-  finishPromise: Promise<Trace>;
-  resolveFinish: (trace: Trace) => void;
+  traceVersion: 2 | 3;
+  supportsTabSwitchSteps: boolean;
+  finishPromise: Promise<RecordedTrace>;
+  resolveFinish: (trace: RecordedTrace) => void;
  rejectFinish: (err: Error) => void;
  settled: boolean;
-  finishing: boolean;
-  currentUrl?: string;
-  pendingNavigation: boolean;
-  pendingNavigationDeadline?: number;
+  finishAttempt: Promise<RecordedTrace | null> | null;
+  observation: RecordingObservationRuntime | null;
+  stoppedBy: StopReason;
+  /** Navigation callbacks tracked from event receipt through action enqueue. */
+  navigationCallbacks: Set<Promise<void>>;
+  /** Synchronous intake gate closed only after finish drains to stability. */
+  acceptingNavigation: boolean;
+  /**
+   * Serializes step appends with navigation observation so a click is always
+   * in `steps` before a same-turn `webNavigation` tries to annotate it.
+   */
+  actionQueue: Promise<void>;
+  /** Last accepted sequence for each content-script document producer. */
+  lastStepSequenceByProducer: Map<string, number>;
+}
+
+function enqueueRecordingAction(
+  recording: ActiveRecording,
+  task: () => Promise<void>,
+): Promise<void> {
+  const queued = recording.actionQueue.then(task, task);
+  recording.actionQueue = queued.catch(() => {});
+  return queued;
+}
+
+function isRecordingFinishing(recording: ActiveRecording): boolean {
+  return recording.settled || recording.finishAttempt !== null;
 }

 const recordings = new Map<string, ActiveRecording>();
@@ -78,6 +118,9 @@ function sleep(ms: number): Promise<void> {
  return new Promise((resolve) => setTimeout(resolve, ms));
 }

+/** Recording producer version mirrored into trace.recorder.bsk. */
+export const BSK_TRACE_VERSION = EXTENSION_VERSION;
+
 /** Injectable http(s) landing page when `tool.record_start` omits `url`. */
 export const RECORD_DEFAULT_START_URL = "https://example.com/";

@@ -137,9 +180,11 @@ async function sendRecordStartWithAck(
  tabId: number,
  msg: RecordStartMessage,
  sendToTab: RecordDeps["sendToTab"],
+  cancelled?: () => boolean,
 ): Promise<void> {
  let lastError: unknown;
  for (let attempt = 0; attempt < RECORD_START_RETRIES; attempt += 1) {
+    if (cancelled?.()) throw new Error("record start cancelled");
    try {
      const response = await sendToTab(tabId, msg);
      if (isRecordStartAck(response)) return;
@@ -147,6 +192,7 @@ async function sendRecordStartWithAck(
    } catch (err) {
      lastError = err;
    }
+    if (cancelled?.()) throw new Error("record start cancelled");
    if (attempt + 1 < RECORD_START_RETRIES) {
      await sleep(RECORD_START_RETRY_DELAY_MS);
    }
@@ -154,19 +200,83 @@ 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);
+function negotiatedTraceVersion(params: RecordStartParams): 2 | 3 | RpcError {
+  if (params.trace_version === undefined) return 2;
+  if (params.trace_version === TRACE_VERSION_V3) return 3;
  return {
-    ...(recording.purpose ? { purpose: recording.purpose } : {}),
-    recorded_at: new Date().toISOString(),
-    started_at: recording.startedAt,
-    entry: { start_url: startUrl },
-    pages,
-    steps,
+    code: "invalid_params",
+    message: `unsupported trace_version ${params.trace_version}; supported values are omitted (v2) or ${TRACE_VERSION_V3} (v3)`,
  };
 }

+function buildTrace(recording: ActiveRecording): RecordedTrace {
+  if (recording.traceVersion === 3 && recording.observation) {
+    return recording.observation.buildTrace({
+      drafts: recording.steps,
+      startedAt: recording.startedAt,
+      purpose: recording.purpose,
+      startUrl: recording.startUrl,
+      stoppedBy: recording.stoppedBy,
+      bskVersion: BSK_TRACE_VERSION,
+      includeTabSwitches: recording.supportsTabSwitchSteps,
+    });
+  }
+  if (recording.traceVersion === 3) {
+    throw new Error("trace v3 observation runtime is unavailable");
+  }
+  return buildTraceV2({
+    steps: recording.steps,
+    startedAt: recording.startedAt,
+    ...(recording.startUrl ? { startUrl: recording.startUrl } : {}),
+    ...(recording.purpose ? { purpose: recording.purpose } : {}),
+  });
+}
+
+function stepBufferFor(
+  recording: ActiveRecording,
+  tabId: number,
+  fallbackUrl?: string,
+): RecordingStepBuffer {
+  return {
+    steps: recording.steps,
+    navigation: recording.tabs.navigation(tabId, fallbackUrl),
+  };
+}
+
+async function activateRecordingTab(
+  recording: ActiveRecording,
+  targetTabId: number,
+): Promise<void> {
+  const previousTabId = recording.tabs.currentTabId;
+  if (targetTabId === previousTabId) return;
+
+  const transition = recording.observation
+    ? await recording.observation.captureTabTransition(previousTabId, targetTabId)
+    : {};
+  const { targetUrl, ...stateLinks } = transition;
+  const draft: Extract<RecordingDraftStep, { op: "switch_tab" }> = {
+    op: "switch_tab",
+    ...stateLinks,
+  };
+  recording.steps.push(draft);
+  recording.observation?.bindTabTransition(draft, recording.steps.length);
+  recording.tabs.commit(targetTabId, targetUrl);
+}
+
+async function processRecordedStep(
+  recording: ActiveRecording,
+  draftIndex: number,
+  tabId: number,
+  producerId?: string,
+): Promise<void> {
+  if (!recording.observation) return;
+  try {
+    await recording.observation.processDraft(tabId, recording.steps, draftIndex, producerId);
+  } catch (err) {
+    console.warn(`[bsk record] observation failed for step ${draftIndex + 1}`, err);
+  }
+}
+
 export interface RecordDeps {
  tabsApi: ChromeTabsApi;
  sendToTab(
@@ -174,16 +284,25 @@ export interface RecordDeps {
    msg: RecordStartMessage | RecordStopMessage | RecordCancelMessage,
  ): Promise<unknown>;
  bypassOverlay?: (tabId: number, enabled: boolean) => Promise<void>;
+  frameCoordinator?: Pick<
+    RecordFrameCoordinator,
+    "begin" | "armTab" | "sourceFor" | "stop" | "cancel"
+  >;
  cdp?: CdpRunner;
  signal?: AbortSignal;
 }

+export type RecordRuntimeDeps = Omit<RecordDeps, "frameCoordinator" | "signal"> & {
+  frameCoordinator: NonNullable<RecordDeps["frameCoordinator"]>;
+};
+
 let defaultDeps: RecordDeps | null = null;
 function getDefaultDeps(): RecordDeps {
  if (!defaultDeps) {
    defaultDeps = {
      tabsApi: chromeTabsApi,
      sendToTab: (tabId, msg) => chrome.tabs.sendMessage(tabId, msg),
+      frameCoordinator: recordFrameCoordinator,
    };
  }
  return defaultDeps;
@@ -241,16 +360,58 @@ export function releaseBrowserObservationListenersIfIdle(): void {
  detachBrowserObservation = null;
 }

-export function attachRecordStepListener(): () => void {
+export function attachRecordStepListener(deps: RecordDeps = getDefaultDeps()): () => void {
  const listener = (
    message: unknown,
-    _sender: chrome.runtime.MessageSender,
-    _sendResponse: () => void,
+    sender: chrome.runtime.MessageSender,
+    sendResponse: (response: RecordStepAck) => void,
  ) => {
    if (!isRecordStepMessage(message)) return false;
    for (const recording of recordings.values()) {
      if (recording.requestId !== message.requestId) continue;
-      appendRecordedPayload(recording, message.step);
+      const source: RecordingCaptureScope | null | undefined = deps.frameCoordinator
+        ? deps.frameCoordinator.sourceFor(message.requestId, message.producerId, sender)
+        : undefined;
+      if (deps.frameCoordinator && !source) return false;
+      const sourceTabId = source?.tabId ?? sender.tab?.id ?? recording.tabs.currentTabId;
+      const sourceWasActive = sender.tab?.active ?? sourceTabId === recording.tabs.activeTabId;
+      const producerKey = source
+        ? `${source.tabId}:${source.documentId}:${source.producerId}`
+        : `${sourceTabId}:${message.producerId}`;
+      const expectedSequence = (recording.lastStepSequenceByProducer.get(producerKey) ?? 0) + 1;
+      if (message.sequence < expectedSequence) {
+        sendResponse({ ok: true, sequence: message.sequence });
+        return false;
+      }
+      if (message.sequence > expectedSequence) {
+        sendResponse({
+          ok: false,
+          expectedSequence,
+          error: `out-of-order recorded step ${message.sequence}`,
+        });
+        return false;
+      }
+
+      recording.lastStepSequenceByProducer.set(producerKey, message.sequence);
+      enqueueRecordingAction(recording, async () => {
+        if (sourceTabId !== recording.tabs.currentTabId) {
+          if (!sourceWasActive) return;
+          if (sourceTabId !== recording.tabs.activeTabId)
+            recording.tabs.noteActivation(sourceTabId);
+          await activateRecordingTab(recording, sourceTabId);
+        }
+        await recording.observation?.flushRedirects(sourceTabId);
+        const targetHint = message.step.geometry ? { geometry: message.step.geometry } : undefined;
+        const draftIndex = appendRecordedPayload(
+          stepBufferFor(recording, sourceTabId, message.step.page_url),
+          message.step,
+          targetHint,
+        );
+        if (draftIndex !== null) {
+          await processRecordedStep(recording, draftIndex, sourceTabId, source?.producerId);
+        }
+      });
+      sendResponse({ ok: true, sequence: message.sequence });
      return false;
    }
    return false;
@@ -277,7 +438,7 @@ export function attachRecordFinishListener(deps: RecordDeps = getDefaultDeps()):

 function findRecordingByTabId(tabId: number): ActiveRecording | null {
  for (const recording of recordings.values()) {
-    if (recording.tabId === tabId && !recording.settled) return recording;
+    if (recording.tabs.currentTabId === tabId && !recording.settled) return recording;
  }
  return null;
 }
@@ -314,7 +475,7 @@ async function clearRearmTimersForRecording(
  recording: ActiveRecording,
  deps: RecordDeps,
 ): Promise<void> {
-  clearRearmTimer(recording.tabId);
+  clearRearmTimer(recording.tabs.currentTabId);
  try {
    const tabs = await deps.tabsApi.query({ windowId: recording.agentWindowId });
    for (const tab of tabs) {
@@ -329,13 +490,16 @@ async function stopRecordingOnAllAgentTabs(
  recording: ActiveRecording,
  deps: RecordDeps,
 ): Promise<void> {
+  if (deps.frameCoordinator && !(await deps.frameCoordinator.stop(recording.requestId))) {
+    throw new Error("failed to flush one or more recording documents");
+  }
  const stopMsg: RecordStopMessage = { type: RECORD_STOP, requestId: recording.requestId };
-  let tabIds = [recording.tabId];
+  let tabIds = [recording.tabs.currentTabId];
  try {
    const tabs = await deps.tabsApi.query({ windowId: recording.agentWindowId });
    tabIds = [
      ...new Set([
-        recording.tabId,
+        recording.tabs.currentTabId,
        ...tabs.flatMap((tab) => (typeof tab.id === "number" ? [tab.id] : [])),
      ]),
    ];
@@ -346,11 +510,11 @@ async function stopRecordingOnAllAgentTabs(
  for (const tabId of tabIds) {
    try {
      const response = await deps.sendToTab(tabId, stopMsg);
-      if (tabId === recording.tabId && !isRecordStartAck(response)) {
+      if (tabId === recording.tabs.currentTabId && !isRecordStartAck(response)) {
        throw new Error("content script did not confirm recorded steps");
      }
    } catch {
-      if (tabId === recording.tabId) {
+      if (tabId === recording.tabs.currentTabId) {
        throw new Error("failed to flush recorded steps");
      }
    }
@@ -368,22 +532,39 @@ async function rearmRecording(
  recording: ActiveRecording,
  targetTabId: number,
  deps: RecordDeps,
+  activation?: TabActivation,
 ): Promise<boolean> {
  // Do NOT toggle automation-bypass here: each retry used to increment the
  // content-script counter, and a single stop decrement left the ControlOverlay
  // stuck with pointer-events:none (page usable, Interrupt dead). RecordOverlay
  // already hides the control chrome while activeRecord is set.
+  const isFinishing = () => isRecordingFinishing(recording);
  for (let attempt = 0; attempt < RECORD_REARM_MAX_ATTEMPTS; attempt += 1) {
+    if (isFinishing()) return false;
    const startMsg: RecordStartMessage = {
      type: RECORD_START,
      requestId: recording.requestId,
      startedAtMs: recording.startedAtMs,
    };
    try {
-      await sendRecordStartWithAck(targetTabId, startMsg, deps.sendToTab);
-      recording.tabId = targetTabId;
+      if (deps.frameCoordinator) {
+        const frameStarted = await deps.frameCoordinator.armTab(recording.requestId, targetTabId);
+        if (!frameStarted) throw new Error("recording document did not start");
+      }
+      await sendRecordStartWithAck(targetTabId, startMsg, deps.sendToTab, isFinishing);
+      if (isFinishing()) return false;
+      if (activation) {
+        if (!recording.tabs.isLatest(activation)) return true;
+        await enqueueRecordingAction(recording, async () => {
+          if (isFinishing() || !recording.tabs.isLatest(activation)) {
+            return;
+          }
+          await activateRecordingTab(recording, targetTabId);
+        });
+      }
      return true;
    } catch {
+      if (isFinishing()) return false;
      if (attempt + 1 < RECORD_REARM_MAX_ATTEMPTS) {
        await sleep(RECORD_REARM_RETRY_DELAY_MS);
      }
@@ -392,7 +573,7 @@ async function rearmRecording(
  return false;
 }

-function scheduleRearmForTab(tabId: number, deps: RecordDeps): void {
+function scheduleRearmForTab(tabId: number, deps: RecordDeps, activation?: TabActivation): void {
  const existing = rearmTimers.get(tabId);
  if (existing) clearTimeout(existing);
  rearmTimers.set(
@@ -401,7 +582,7 @@ function scheduleRearmForTab(tabId: number, deps: RecordDeps): void {
      rearmTimers.delete(tabId);
      void (async () => {
        const current = await findRecordingForTab(tabId, deps);
-        if (current) await rearmRecording(current, tabId, deps);
+        if (current) await rearmRecording(current, tabId, deps, activation);
      })();
    }, RECORD_REARM_DEBOUNCE_MS),
  );
@@ -413,14 +594,20 @@ export function attachRecordTabListener(deps: RecordDeps = getDefaultDeps()): ()
    const windowId = tab.windowId;
    if (tabId === undefined || windowId === undefined) return;
    for (const recording of recordings.values()) {
-      if (recording.settled || recording.agentWindowId !== windowId) continue;
+      if (isRecordingFinishing(recording) || recording.agentWindowId !== windowId) continue;
      scheduleRearmForTab(tabId, deps);
      return;
    }
  };

  const onActivated = (activeInfo: chrome.tabs.TabActiveInfo) => {
-    scheduleRearmForTab(activeInfo.tabId, deps);
+    for (const recording of recordings.values()) {
+      if (isRecordingFinishing(recording) || recording.agentWindowId !== activeInfo.windowId)
+        continue;
+      const activation = recording.tabs.noteActivation(activeInfo.tabId);
+      scheduleRearmForTab(activeInfo.tabId, deps, activation);
+      return;
+    }
  };

  chrome.tabs.onCreated.addListener(onCreated);
@@ -432,13 +619,47 @@ export function attachRecordTabListener(deps: RecordDeps = getDefaultDeps()): ()
 }

 export function attachRecordNavigationListener(deps: RecordDeps = getDefaultDeps()): () => void {
-  const observeMainFrame = (tabId: number, url?: string, causedByAction?: boolean) => {
-    void (async () => {
-      const recording = await findRecordingForTab(tabId, deps);
-      if (recording && url) {
-        observeRecordedNavigation(recording, url, causedByAction);
-      }
-    })();
+  const observeMainFrame = (
+    tabId: number,
+    url?: string,
+    causedByAction?: boolean,
+    transitionType?: string,
+    transitionQualifiers?: string[],
+  ) => {
+    if (!url) return;
+    const candidates = [...recordings.values()].filter(
+      (recording) =>
+        !recording.settled && recording.acceptingNavigation && recording.tabs.activeTabId === tabId,
+    );
+    for (const recording of candidates) {
+      const queued = enqueueRecordingAction(recording, async () => {
+        if (tabId !== recording.tabs.currentTabId) {
+          await activateRecordingTab(recording, tabId);
+        }
+        const result = observeRecordedNavigation(
+          stepBufferFor(recording, tabId, url),
+          url,
+          causedByAction,
+          transitionType,
+          transitionQualifiers,
+        );
+        if (result.kind === "coalesce_redirect") {
+          recording.observation?.scheduleRedirect(tabId, recording.steps, result.url);
+          return;
+        }
+
+        if (result.kind === "noop") return;
+        recording.observation?.clearRedirect(tabId);
+        if (result.kind === "appended") {
+          await processRecordedStep(recording, result.index, tabId);
+        } else {
+          recording.observation?.scheduleSettle(tabId, recording.steps, result.index);
+        }
+      });
+      const tracked = queued.catch(() => {});
+      recording.navigationCallbacks.add(tracked);
+      void tracked.finally(() => recording.navigationCallbacks.delete(tracked));
+    }
  };
  const onMainFrameComplete = (tabId: number, url?: string) => {
    void (async () => {
@@ -458,18 +679,13 @@ export function attachRecordNavigationListener(deps: RecordDeps = getDefaultDeps
      details: chrome.webNavigation.WebNavigationTransitionCallbackDetails,
    ) => {
      if (details.frameId !== 0) return;
-      const causedByAction =
-        details.transitionType === "link" || details.transitionType === "form_submit"
-          ? true
-          : details.transitionType === "typed" ||
-              details.transitionType === "auto_bookmark" ||
-              details.transitionType === "generated" ||
-              details.transitionType === "keyword" ||
-              details.transitionType === "keyword_generated" ||
-              details.transitionType === "reload"
-            ? false
-            : undefined;
-      observeMainFrame(details.tabId, details.url, causedByAction);
+      observeMainFrame(
+        details.tabId,
+        details.url,
+        undefined,
+        details.transitionType,
+        details.transitionQualifiers,
+      );
    };
    chrome.webNavigation.onCompleted.addListener(completedListener);
    chrome.webNavigation.onCommitted?.addListener(committedListener);
@@ -487,6 +703,26 @@ export function attachRecordNavigationListener(deps: RecordDeps = getDefaultDeps
  return () => chrome.tabs.onUpdated.removeListener(listener);
 }

+const MAX_FINISH_DRAIN_ROUNDS = 10;
+
+async function drainRecordingToStability(recording: ActiveRecording): Promise<boolean> {
+  for (let round = 0; round < MAX_FINISH_DRAIN_ROUNDS; round += 1) {
+    await Promise.all([...recording.navigationCallbacks]);
+    const actionTail = recording.actionQueue;
+    await actionTail;
+    await recording.observation?.flush();
+
+    if (recording.navigationCallbacks.size === 0 && recording.actionQueue === actionTail) {
+      // No event or promise continuation can interleave with this synchronous
+      // check-and-close, so work accepted before the cutoff is fully drained.
+      recording.acceptingNavigation = false;
+      return true;
+    }
+  }
+  console.warn("[bsk record] navigation/action queues did not stabilize at stop");
+  return false;
+}
+
 export function attachRecordQueryListener(deps: RecordDeps = getDefaultDeps()): () => void {
  const listener = (
    message: unknown,
@@ -505,7 +741,8 @@ export function attachRecordQueryListener(deps: RecordDeps = getDefaultDeps()):
        sendResponse({ active: false });
        return;
      }
-      await rearmRecording(recording, tabId, deps);
+      const activation = sender.tab?.active ? recording.tabs.noteActivation(tabId) : undefined;
+      await rearmRecording(recording, tabId, deps, activation);
      sendResponse({
        active: true,
        requestId: recording.requestId,
@@ -527,23 +764,50 @@ async function finishRecordingByRequest(
    if (recording.requestId !== requestId || recording.settled) continue;
    const match = await findRecordingForTab(tabId, deps);
    if (match !== recording) continue;
-    await finishRecording(sessionId, deps);
+    await finishRecording(sessionId, deps, "user_finish");
    return;
  }
 }

-async function finishRecording(sessionId: string, deps: RecordDeps): Promise<Trace | null> {
+async function finishRecording(
+  sessionId: string,
+  deps: RecordDeps,
+  stoppedBy: StopReason,
+): Promise<RecordedTrace | null> {
  const recording = recordings.get(sessionId);
-  if (!recording || recording.settled || recording.finishing) return null;
-  recording.finishing = true;
+  if (!recording || recording.settled) return null;
+  if (recording.finishAttempt) return recording.finishAttempt;
+  recording.stoppedBy = stoppedBy;

+  const attempt = finishRecordingAttempt(sessionId, recording, deps);
+  recording.finishAttempt = attempt;
+  try {
+    return await attempt;
+  } finally {
+    if (!recording.settled) {
+      recording.finishAttempt = null;
+    }
+  }
+}
+
+async function finishRecordingAttempt(
+  sessionId: string,
+  recording: ActiveRecording,
+  deps: RecordDeps,
+): Promise<RecordedTrace | null> {
  await clearRearmTimersForRecording(recording, deps);
  try {
+    // Disposing content capture may commit a final dirty fill. Flush content
+    // first so all resulting RECORD_STEP messages enter actionQueue before it
+    // and the observation queues are drained.
    await stopRecordingOnAllAgentTabs(recording, deps);
  } catch {
-    recording.finishing = false;
    return null;
  }
+  if (!(await drainRecordingToStability(recording))) {
+    return null;
+  }
+  await recording.observation?.settleTrailing(recording.tabs.currentTabId, recording.steps);

  recording.settled = true;
  recordings.delete(sessionId);
@@ -558,6 +822,15 @@ export async function handleRecordStart(
  params: RecordStartParams,
  deps: RecordDeps = getDefaultDeps(),
 ): Promise<RecordStartResult | RpcError> {
+  const traceVersionOrErr = negotiatedTraceVersion(params);
+  if (typeof traceVersionOrErr !== "number") return traceVersionOrErr;
+  if (traceVersionOrErr === 3 && !deps.cdp) {
+    return {
+      code: "protocol_error",
+      message: "trace v3 recording requires an active CDP connection",
+    };
+  }
+
  const ctxOrErr = lookupSession(manager, params, "record_start");
  if (isRpcError(ctxOrErr)) return ctxOrErr;
  const ctx = ctxOrErr;
@@ -574,37 +847,64 @@ 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: RecordedTrace) => void;
  let rejectFinish!: (err: Error) => void;
-  const finishPromise = new Promise<Trace>((resolve, reject) => {
+  const finishPromise = new Promise<RecordedTrace>((resolve, reject) => {
    resolveFinish = resolve;
    rejectFinish = reject;
  });
  const navigateUrl = params.url ?? RECORD_DEFAULT_START_URL;
  const startedAtMs = Date.now();
+  const maxPageTokens = params.max_page_tokens;
+  const redactValues = params.redact_values ?? false;
  recordings.set(params.session_id, {
    requestId,
-    tabId: target.tabId,
+    tabs: new RecordingTabCoordinator(target.tabId, navigateUrl),
    agentWindowId: ctx.agentWindowId,
    startUrl: navigateUrl,
    ...(params.purpose ? { purpose: params.purpose } : {}),
    steps: [],
    startedAt: new Date(startedAtMs).toISOString(),
    startedAtMs,
+    traceVersion: traceVersionOrErr,
+    supportsTabSwitchSteps: params.supports_tab_switch_steps === true,
    finishPromise,
    resolveFinish,
    rejectFinish,
    settled: false,
-    finishing: false,
-    currentUrl: navigateUrl,
-    pendingNavigation: false,
-    pendingNavigationDeadline: undefined,
+    finishAttempt: null,
+    observation:
+      traceVersionOrErr === 3 && deps.cdp
+        ? new RecordingObservationRuntime({
+            cdp: deps.cdp,
+            tabsApi: deps.tabsApi,
+            maxTokens: maxPageTokens,
+            redactValues,
+          })
+        : null,
+    stoppedBy: "user_finish",
+    navigationCallbacks: new Set(),
+    acceptingNavigation: true,
+    actionQueue: Promise.resolve(),
+    lastStepSequenceByProducer: new Map(),
+  });
+  deps.frameCoordinator?.begin(requestId, startedAtMs, target.tabId, async (scope) => {
+    const recording = recordings.get(params.session_id);
+    if (!recording || recording.requestId !== requestId || recording.settled) return;
+    try {
+      await recording.observation?.refreshDocument(scope.tabId, scope.producerId);
+    } catch {
+      // The normal action-time capture remains available if a child Document
+      // is replaced while its readiness refresh is in flight.
+    }
  });
  // Observe navigations for the whole recording lifetime; attach before
  // optional navigate so the destination load can rearm capture.
  ensureBrowserObservationListeners(deps);

  const abortPending = async (notifyContent: boolean) => {
+    recordings.get(params.session_id)?.observation?.cancel();
+    deps.frameCoordinator?.cancel(requestId);
    recordings.delete(params.session_id);
    releaseBrowserObservationListenersIfIdle();
    if (notifyContent) {
@@ -686,7 +986,7 @@ export async function handleRecordStart(
    return cancelledError();
  }
  active.startUrl = startUrl;
-  active.currentUrl = startUrl;
+  active.tabs.navigation(target.tabId, startUrl).currentUrl = startUrl;

  if (isContentScriptRestrictedUrl(startUrl)) {
    await abortPending(false);
@@ -694,7 +994,7 @@ export async function handleRecordStart(
      code: "invalid_params",
      message: params.url
        ? `cannot record on restricted URL (${startUrl}); use an http(s) page`
-        : `cannot record on restricted URL (${startUrl}); default start page must be injectable http(s)`,
+        : `cannot record on restricted URL (${startUrl}); default start page https://example.com/ did not load — pass --url with a page you can open`,
    };
  }

@@ -721,6 +1021,10 @@ export async function handleRecordStart(
  const startMsg: RecordStartMessage = { type: RECORD_START, requestId, startedAtMs };

  try {
+    if (deps.frameCoordinator) {
+      const frameStarted = await deps.frameCoordinator.armTab(requestId, target.tabId);
+      if (!frameStarted) throw new Error("top recording document did not start");
+    }
    await sendRecordStartWithAck(target.tabId, startMsg, deps.sendToTab);
  } catch {
    await abortPending(true);
@@ -731,6 +1035,17 @@ export async function handleRecordStart(
    };
  }

+  if (active.observation) {
+    const activeRecording = recordings.get(params.session_id);
+    if (activeRecording) {
+      try {
+        await activeRecording.observation?.captureInitial(target.tabId);
+      } catch {
+        // Proceed without initial observation; steps may be dropped by reducer.
+      }
+    }
+  }
+
  {
    const cancelled = await abortIfCancelled(true);
    if (cancelled) return cancelled;
@@ -755,7 +1070,7 @@ export async function handleRecordStop(
    };
  }

-  const trace = await finishRecording(params.session_id, deps);
+  const trace = await finishRecording(params.session_id, deps, "cli_stop");
  if (!trace) {
    return {
      code: "protocol_error",
@@ -785,9 +1100,9 @@ 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: RecordedTrace } | { error: RpcError }>((resolve) => {
    let settled = false;
-    const finish = (result: { trace: Trace } | { error: RpcError }) => {
+    const finish = (result: { trace: RecordedTrace } | { error: RpcError }) => {
      if (settled) return;
      settled = true;
      if (timer) clearTimeout(timer);
@@ -829,6 +1144,8 @@ export function clearRecordingForSession(sessionId: string): void {
  }
  void clearRearmTimersForRecording(recording, getDefaultDeps());
  if (!recording.settled) {
+    getDefaultDeps().frameCoordinator?.cancel(recording.requestId);
+    recording.observation?.cancel();
    recording.settled = true;
    recording.rejectFinish(new Error("recording cleared"));
  }
@@ -53,6 +53,7 @@ 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>;
+  detach?(tabId: number): Promise<void>;
  getFrameGraph?(tabId: number): Promise<CdpFrameGraph>;
  ensureAttachedToUrl?(tabId: number, expectedUrl: string | undefined): Promise<void>;
  trackSessionTab?(sessionId: string, tabId: number): void;
@@ -0,0 +1,59 @@
+// Upload orchestration: validate the session-scoped request, resolve its click
+// target, then delegate the browser protocol transaction to the file-input
+// transaction module.
+
+import type { SessionManager } from "@/session-manager/manager";
+import type { RpcError, UploadParams, UploadResult } from "@/transport/types";
+import { uploadThroughActivatedFileInput } from "./file-input-transaction";
+import { clickResolvedTarget, type InteractionDeps, resolveActionTarget } from "./interaction";
+import {
+  type CdpRunner,
+  enforceAgentWindow,
+  isRpcError,
+  lookupSession,
+  resolveTargetTab,
+} from "./shared";
+
+const DEFAULT_TIMEOUT_MS = 120_000;
+
+export interface UploadDeps extends InteractionDeps {
+  cdp: CdpRunner;
+}
+
+export async function handleUpload(
+  manager: SessionManager,
+  params: UploadParams,
+  deps: UploadDeps,
+): Promise<UploadResult | RpcError> {
+  const ctx = lookupSession(manager, params, "upload");
+  if (isRpcError(ctx)) return ctx;
+  const target = await resolveTargetTab(manager, ctx, params.tab_id, deps.tabsApi);
+  if (isRpcError(target)) return target;
+  const denied = enforceAgentWindow(ctx, target, "upload");
+  if (denied) return denied;
+  if (
+    params.files.length === 0 ||
+    params.files.length > 20 ||
+    params.files.some((file) => !file.staged_path)
+  ) {
+    return { code: "invalid_params", message: "upload requires daemon-staged files" };
+  }
+  const address = await resolveActionTarget(deps.cdp, ctx, target, params, "upload");
+  if (isRpcError(address)) return address;
+  const timeoutMs = params.timeout_ms ?? DEFAULT_TIMEOUT_MS;
+  const transaction = await uploadThroughActivatedFileInput({
+    cdp: deps.cdp,
+    actionTarget: address,
+    files: params.files.map((file) => file.staged_path as string),
+    timeoutMs,
+    signal: deps.signal,
+    trigger: () => clickResolvedTarget(ctx, address, {}, deps),
+  });
+  if (isRpcError(transaction)) return transaction;
+  return {
+    tab_id: target.tabId,
+    used_ref: transaction.click.used_ref,
+    used_selector: transaction.click.used_selector,
+    file_names: params.files.map((file) => file.name),
+  };
+}
@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 import { OVERLAY_HOST_MARKER_ATTR, OVERLAY_HOST_NAME } from "../../../lib/overlay-bridge";
-import { captureViewModel, collectOverlayExcludedBackendIds } from "../capture";
+import { captureViewModel, collectOverlayExcludedBackendIds, probeHoverSurfaces } from "../capture";

 // Minimal but format-accurate captureSnapshot reply: a body with one
 // fixed full-screen overlay div carrying a password input.
@@ -36,7 +36,7 @@ function fakeSnapshotReply() {
        },
        layout: {
          nodeIndex: [1, 2, 3],
-          // styles columns follow requested computedStyles order: [position, pointer-events]
+          // Legacy fixture: omitted style columns fall back to visible defaults.
          styles: [
            [i("static"), i("auto")],
            [i("fixed"), i("auto")],
@@ -251,11 +251,10 @@ describe("captureViewModel", () => {
    expect(input?.attrs).toEqual({ type: "password" });
  });

-  it("does not run conditional surface probes by default", async () => {
+  it("never hovers the page while capturing", async () => {
    const cdp = makeCdp(fakeSnapshotReply());
-    const result = await captureViewModel(cdp, 4);
+    await captureViewModel(cdp, 4);

-    expect(result.surfaceProbes).toEqual([]);
    expect(cdp.send).not.toHaveBeenCalledWith(4, "Input.dispatchMouseEvent", expect.anything());
  });

@@ -319,9 +318,10 @@ describe("captureViewModel", () => {
      }) as unknown as <T>(tabId: number, method: string, params?: object) => Promise<T>,
    };

-    const result = await captureViewModel(cdp, 4, { conditionalSurfaceProbe: true });
+    const captured = await captureViewModel(cdp, 4);
+    const surfaceProbes = await probeHoverSurfaces(cdp, 4, captured.nodes);

-    expect(result.surfaceProbes).toEqual([
+    expect(surfaceProbes).toEqual([
      {
        triggerBackendNodeId: 12,
        triggerPoint: { x: 956, y: 32 },
@@ -378,9 +378,10 @@ describe("captureViewModel", () => {
      }) as unknown as <T>(tabId: number, method: string, params?: object) => Promise<T>,
    };

-    const result = await captureViewModel(cdp, 4, { conditionalSurfaceProbe: true });
+    const captured = await captureViewModel(cdp, 4);
+    const surfaceProbes = await probeHoverSurfaces(cdp, 4, captured.nodes);

-    expect(result.surfaceProbes).toEqual([
+    expect(surfaceProbes).toEqual([
      expect.objectContaining({
        triggerBackendNodeId: 12,
        subItems: ["My profile", "Sign out"],
@@ -422,7 +423,8 @@ describe("captureViewModel", () => {
      }) as unknown as <T>(tabId: number, method: string, params?: object) => Promise<T>,
    };

-    await captureViewModel(cdp, 4, { conditionalSurfaceProbe: true });
+    const captured = await captureViewModel(cdp, 4);
+    await probeHoverSurfaces(cdp, 4, captured.nodes);

    expect(hoverMoves).toBe(1);
  });
@@ -682,6 +684,46 @@ describe("captureViewModel", () => {
    expect(nodes.find((n) => n.backendNodeId === 11)?.cursor).toBe("auto");
  });

+  it("captures painted visibility as DOM fallback evidence", async () => {
+    const S = ["html", "body", "button", "static", "auto", "visible", "hidden", "1", "0"];
+    const i = (value: string) => S.indexOf(value);
+    const snapshot = {
+      strings: S,
+      documents: [
+        {
+          nodes: {
+            parentIndex: [-1, 0, 1, 1, 1],
+            nodeName: [i("html"), i("body"), i("button"), i("button"), i("button")],
+            backendNodeId: [10, 11, 12, 13, 14],
+            attributes: [[], [], [], [], []],
+          },
+          layout: {
+            nodeIndex: [1, 2, 3, 4],
+            styles: [
+              [i("static"), i("auto"), i("auto"), i("visible"), i("1")],
+              [i("static"), i("auto"), i("auto"), i("visible"), i("1")],
+              [i("static"), i("auto"), i("auto"), i("hidden"), i("1")],
+              [i("static"), i("auto"), i("auto"), i("visible"), i("0")],
+            ],
+            bounds: [
+              [0, 0, 1000, 800],
+              [10, 10, 100, 30],
+              [10, 50, 100, 30],
+              [10, 90, 100, 30],
+            ],
+            paintOrders: [0, 1, 2, 3],
+          },
+        },
+      ],
+    };
+
+    const { nodes } = await captureViewModel(makeCdp(snapshot), 4);
+
+    expect(nodes.find((node) => node.backendNodeId === 12)?.rendered).toBe(true);
+    expect(nodes.find((node) => node.backendNodeId === 13)?.rendered).toBe(false);
+    expect(nodes.find((node) => node.backendNodeId === 14)?.rendered).toBe(false);
+  });
+
  it("subtracts scroll offset to make rects viewport-relative", async () => {
    const cdp = {
      send: vi.fn(async (_t: number, method: string) => {
@@ -132,4 +132,67 @@ describe("captureFrameData", () => {
      ]),
    );
  });
+
+  it("keeps OOPIF semantics when viewport projection is unavailable", async () => {
+    const owner = { ...ownerNode(10, 50), rect: null, localRect: null };
+    const captured: CapturedViewModel = {
+      nodes: [owner],
+      viewport: { width: 1000, height: 800 },
+      iframeNodes: new Map(),
+      frameNodes: new Map([["main", [owner]]]),
+      rootFrameId: "main",
+      excludedBackendNodeIds: new Set(),
+    };
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method) => {
+        if (method === "Accessibility.enable") return {};
+        if (method === "Accessibility.getFullAXTree") return { nodes: [] };
+        if (method === "DOM.getBoxModel") throw new Error("owner geometry unavailable");
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 1000, clientHeight: 800 } };
+        }
+        throw new Error(`unexpected root ${method}`);
+      }) as CdpRunner["send"],
+      sendToTarget: vi.fn(async (_target, method) => {
+        if (method === "Page.getLayoutMetrics") throw new Error("viewport unavailable");
+        if (method === "DOMSnapshot.enable" || method === "Accessibility.enable") return {};
+        if (method === "DOMSnapshot.captureSnapshot") return childSnapshot("child", 101);
+        if (method === "Accessibility.getFullAXTree") {
+          return {
+            nodes: [
+              {
+                nodeId: "button",
+                backendDOMNodeId: 101,
+                role: { type: "role", value: "button" },
+                name: { type: "computedString", value: "Continue" },
+              },
+            ],
+          };
+        }
+        throw new Error(`unexpected ${method}`);
+      }) as unknown as NonNullable<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 documents = await captureFrameData(cdp, 4, captured);
+    const childDocument = documents.find((document) => document.frameId === "child");
+
+    expect(childDocument?.axNodes).toEqual([
+      expect.objectContaining({ backendDOMNodeId: 101, frameId: "child" }),
+    ]);
+    expect(childDocument?.domNodes.find((node) => node.backendNodeId === 101)).toEqual(
+      expect.objectContaining({ rect: null, localRect: { x: 10, y: 20, w: 100, h: 40 } }),
+    );
+  });
 });
@@ -0,0 +1,84 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { ProbeBudget, resetOverlayBypassDepth, withOverlayBypass } from "../hover-perception";
+
+afterEach(() => {
+  resetOverlayBypassDepth();
+});
+
+describe("ProbeBudget", () => {
+  it("refuses a candidate that cannot finish inside the budget", () => {
+    const budget = new ProbeBudget(500);
+
+    expect(budget.canAfford(400)).toBe(true);
+    expect(budget.canAfford(600)).toBe(false);
+  });
+
+  it("stops admitting candidates once the remaining budget is smaller than one", async () => {
+    const budget = new ProbeBudget(60);
+    await new Promise((resolve) => setTimeout(resolve, 40));
+
+    // A top-of-loop `elapsed > total` check would still admit this candidate
+    // and then overshoot by its full cost.
+    expect(budget.canAfford(50)).toBe(false);
+  });
+});
+
+describe("withOverlayBypass", () => {
+  it("toggles the overlay once around nested probe phases", async () => {
+    const bypass = vi.fn(async () => {});
+
+    await withOverlayBypass(bypass, 4, async () => {
+      await withOverlayBypass(bypass, 4, async () => {
+        expect(bypass).toHaveBeenCalledTimes(1);
+      });
+      expect(bypass).toHaveBeenCalledTimes(1);
+    });
+
+    expect(bypass.mock.calls).toEqual([
+      [4, true],
+      [4, false],
+    ]);
+  });
+
+  it("restores the overlay when the probe throws", async () => {
+    const bypass = vi.fn(async () => {});
+
+    await expect(
+      withOverlayBypass(bypass, 4, async () => {
+        throw new Error("probe exploded");
+      }),
+    ).rejects.toThrow("probe exploded");
+
+    expect(bypass).toHaveBeenLastCalledWith(4, false);
+  });
+
+  it("reports a failed restore instead of swallowing it", async () => {
+    const onRestoreFailure = vi.fn();
+    const bypass = vi.fn(async (_tabId: number, enabled: boolean) => {
+      if (!enabled) throw new Error("tab is gone");
+    });
+
+    await withOverlayBypass(bypass, 4, async () => undefined, { onRestoreFailure });
+
+    expect(onRestoreFailure).toHaveBeenCalledTimes(1);
+  });
+
+  it("does not pin the overlay off for the tab when a restore fails", async () => {
+    const failing = vi.fn(async (_tabId: number, enabled: boolean) => {
+      if (!enabled) throw new Error("tab is gone");
+    });
+    await withOverlayBypass(failing, 4, async () => undefined, { onRestoreFailure: () => {} });
+
+    const bypass = vi.fn(async () => {});
+    await withOverlayBypass(bypass, 4, async () => undefined);
+
+    expect(bypass.mock.calls).toEqual([
+      [4, true],
+      [4, false],
+    ]);
+  });
+
+  it("runs the probe untouched when no bypass is wired up", async () => {
+    await expect(withOverlayBypass(undefined, 4, async () => "done")).resolves.toBe("done");
+  });
+});
@@ -0,0 +1,214 @@
+import { describe, expect, it, vi } from "vitest";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import type { CdpRunner } from "../../shared";
+import type { CapturedNode } from "../capture";
+import type { FrameDocument, FrameOwnedAxNode } from "../frame-document";
+import { probeTooltipNames } from "../name-enrichment";
+import { buildSemanticGraph, resolveSemanticGraph } from "../semantic-graph";
+import { stableIdentifierName } from "../semantic-graph/name-evidence";
+import { frameBackendKey } from "../semantic-graph/types";
+
+function document(
+  target: CdpTarget,
+  backendNodeId: number,
+  accessibleName?: string,
+  frameId = "child",
+  x = 10,
+): FrameDocument<FrameOwnedAxNode> {
+  const node: CapturedNode = {
+    backendNodeId,
+    parentBackendNodeId: null,
+    frameId,
+    tag: "button",
+    attrs: {
+      id: "toolInsertRecord",
+      "data-test-id": "toolInsertRecord",
+      ...(accessibleName ? { "aria-label": accessibleName } : {}),
+    },
+    rect: { x, y: 20, w: 40, h: 30 },
+    localRect: { x: 2, y: 3, w: 40, h: 30 },
+    paintOrder: 1,
+    position: "static",
+    pointerEvents: "auto",
+    cursor: "pointer",
+  };
+  return {
+    frameId,
+    parentFrameId: "main",
+    contextScopeId: "child",
+    target,
+    axNodes: [],
+    domNodes: [node],
+    url: "https://example.com/frame",
+  };
+}
+
+function semantics(documents: FrameDocument<FrameOwnedAxNode>[]) {
+  return resolveSemanticGraph(
+    buildSemanticGraph({
+      documents,
+      viewport: { width: 800, height: 600 },
+      rootFrameId: documents[0]?.frameId,
+    }),
+    { identifierFallback: false },
+  );
+}
+
+describe("tooltip name enrichment", () => {
+  it("uses the owning frame target and upgrades an identifier name from a tooltip", async () => {
+    const target = { tabId: 7, sessionId: "oopif-session" };
+    let hovered = false;
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method, params) => {
+        if (method === "Input.dispatchMouseEvent") {
+          hovered = (params as { x?: number }).x === 30;
+        }
+        return {};
+      }) as CdpRunner["send"],
+      sendToTarget: vi.fn(async (_target, method) => {
+        if (method === "Page.createIsolatedWorld") return { executionContextId: 11 };
+        if (method === "DOM.resolveNode") return { object: { objectId: "button-501" } };
+        if (method === "Runtime.callFunctionOn") {
+          return { result: { value: hovered ? ["插入行"] : [] } };
+        }
+        return {};
+      }) as CdpRunner["sendToTarget"],
+    };
+
+    const documents = [document(target, 501)];
+    const graph = semantics(documents);
+    const names = await probeTooltipNames(cdp, 7, documents, graph);
+
+    expect(names.get(frameBackendKey("child", 501))).toBe("插入行");
+    expect(cdp.sendToTarget).toHaveBeenCalledWith(
+      target,
+      "Page.createIsolatedWorld",
+      expect.objectContaining({ frameId: "child" }),
+    );
+
+    const sendsBeforeCache = vi.mocked(cdp.send).mock.calls.length;
+    const targetSendsBeforeCache = vi.mocked(
+      cdp.sendToTarget as NonNullable<CdpRunner["sendToTarget"]>,
+    ).mock.calls.length;
+    const cached = await probeTooltipNames(cdp, 7, documents, graph);
+    expect(cached.get(frameBackendKey("child", 501))).toBe("插入行");
+    expect(cdp.send).toHaveBeenCalledTimes(sendsBeforeCache);
+    expect(cdp.sendToTarget).toHaveBeenCalledTimes(targetSendsBeforeCache);
+  });
+
+  it("does not probe controls that already have a higher-confidence name", async () => {
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      sendToTarget: vi.fn(async () => ({ executionContextId: 12 })) as CdpRunner["sendToTarget"],
+    };
+
+    const documents = [document({ tabId: 8 }, 601, "Add a new record")];
+    const names = await probeTooltipNames(cdp, 8, documents, semantics(documents));
+
+    expect(names.size).toBe(0);
+    expect(cdp.send).not.toHaveBeenCalled();
+    expect(cdp.sendToTarget).not.toHaveBeenCalled();
+  });
+
+  it("does not collect supplemental names from form controls", async () => {
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      sendToTarget: vi.fn(async () => ({ executionContextId: 12 })) as CdpRunner["sendToTarget"],
+    };
+    const inputDocument = document({ tabId: 8 }, 602);
+    inputDocument.domNodes[0] = {
+      ...inputDocument.domNodes[0],
+      tag: "input",
+      attrs: { type: "email" },
+      formValue: "user@example.com",
+      formDefaultValue: "",
+      formState: "filled",
+    };
+
+    const names = await probeTooltipNames(cdp, 8, [inputDocument], semantics([inputDocument]));
+
+    expect(names.size).toBe(0);
+    expect(cdp.send).not.toHaveBeenCalled();
+    expect(cdp.sendToTarget).not.toHaveBeenCalled();
+  });
+
+  it("remembers controls that revealed no tooltip so the miss is paid once", async () => {
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      sendToTarget: vi.fn(async (_target, method) => {
+        if (method === "Page.createIsolatedWorld") return { executionContextId: 31 };
+        if (method === "DOM.resolveNode") return { object: { objectId: "button-801" } };
+        if (method === "Runtime.callFunctionOn") return { result: { value: [] } };
+        return {};
+      }) as CdpRunner["sendToTarget"],
+    };
+
+    const documents = [
+      document({ tabId: 11, sessionId: "miss-session" }, 801, undefined, "miss-frame"),
+    ];
+    const graph = semantics(documents);
+
+    const first = await probeTooltipNames(cdp, 11, documents, graph);
+    expect(first.size).toBe(0);
+    const hoversAfterFirst = vi
+      .mocked(cdp.send)
+      .mock.calls.filter(([, method]) => method === "Input.dispatchMouseEvent").length;
+    expect(hoversAfterFirst).toBeGreaterThan(0);
+
+    const second = await probeTooltipNames(cdp, 11, documents, graph);
+    expect(second.size).toBe(0);
+    expect(
+      vi.mocked(cdp.send).mock.calls.filter(([, method]) => method === "Input.dispatchMouseEvent")
+        .length,
+    ).toBe(hoversAfterFirst);
+  });
+
+  it("keeps tooltip evidence isolated across sibling frame sessions", async () => {
+    let hoveredX = -10;
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method, params) => {
+        if (method === "Input.dispatchMouseEvent") {
+          hoveredX = (params as { x: number }).x;
+        }
+        return {};
+      }) as CdpRunner["send"],
+      sendToTarget: vi.fn(async (target, method, params) => {
+        if (method === "Page.createIsolatedWorld") {
+          return { executionContextId: target.sessionId === "left-session" ? 21 : 22 };
+        }
+        if (method === "DOM.resolveNode") {
+          return { object: { objectId: target.sessionId === "left-session" ? "left" : "right" } };
+        }
+        if (method === "Runtime.callFunctionOn") {
+          const objectId = (params as { objectId: string }).objectId;
+          const value =
+            objectId === "left" && hoveredX === 30
+              ? ["Left action"]
+              : objectId === "right" && hoveredX === 130
+                ? ["Right action"]
+                : [];
+          return { result: { value } };
+        }
+        return {};
+      }) as CdpRunner["sendToTarget"],
+    };
+    const documents = [
+      document({ tabId: 9, sessionId: "left-session" }, 701, undefined, "left", 10),
+      document({ tabId: 9, sessionId: "right-session" }, 701, undefined, "right", 110),
+    ];
+
+    const names = await probeTooltipNames(cdp, 9, documents, semantics(documents));
+
+    expect(names.get(frameBackendKey("left", 701))).toBe("Left action");
+    expect(names.get(frameBackendKey("right", 701))).toBe("Right action");
+  });
+});
+
+describe("stable identifier evidence", () => {
+  it("accepts readable action identifiers and rejects framework-generated ids", () => {
+    expect(stableIdentifierName({ id: "toolInsertRecord" })).toBe("Insert record");
+    expect(stableIdentifierName({ id: "reactivateAccount" })).toBe("Reactivate account");
+    expect(stableIdentifierName({ id: "headlessui-menu-button-r1" })).toBeUndefined();
+    expect(stableIdentifierName({ id: "7f15a3bc91" })).toBeUndefined();
+  });
+});
@@ -0,0 +1,82 @@
+import { describe, expect, it } from "vitest";
+import {
+  RECORD_DOCUMENT_ATTRIBUTE,
+  recordingDocumentMarkerValue,
+} from "@/shared/recording-document-identity";
+import { projectRecordSafeObservation } from "../record-safe-observation";
+
+describe("projectRecordSafeObservation", () => {
+  it("projects the opaque recording identity without exposing captured attributes", () => {
+    const recordingDocumentId = "123e4567-e89b-42d3-a456-426614174000";
+    const result = projectRecordSafeObservation({
+      rootFrameId: "child",
+      frameDocuments: [
+        {
+          frameId: "child",
+          target: { tabId: 4, sessionId: "oopif-session" },
+          contextScopeId: "scope-1",
+          axNodes: [],
+          domNodes: [
+            {
+              backendNodeId: 1,
+              parentBackendNodeId: null,
+              tag: "html",
+              attrs: {
+                [RECORD_DOCUMENT_ATTRIBUTE]: recordingDocumentMarkerValue(recordingDocumentId),
+                value: "user@example.com",
+              },
+              rect: null,
+              paintOrder: 0,
+              position: "static",
+              pointerEvents: "auto",
+            },
+          ],
+        },
+      ],
+      rendered: { text: '@vom 1\nRootWebArea "Example"', refs: [], truncated: false },
+    });
+
+    expect(result.frames).toEqual([
+      {
+        frameId: "child",
+        target: { tabId: 4, sessionId: "oopif-session" },
+        recordingDocumentId,
+      },
+    ]);
+    const dumped = JSON.stringify(result);
+    expect(dumped).not.toContain("user@example.com");
+    expect(dumped).not.toContain("attrs");
+    expect(dumped).not.toContain("domNodes");
+    expect(dumped).not.toContain("axNodes");
+  });
+
+  it("does not project a page-controlled marker value as recording identity", () => {
+    const result = projectRecordSafeObservation({
+      rootFrameId: "root",
+      frameDocuments: [
+        {
+          frameId: "root",
+          target: { tabId: 4 },
+          contextScopeId: "scope-1",
+          axNodes: [],
+          domNodes: [
+            {
+              backendNodeId: 1,
+              parentBackendNodeId: null,
+              tag: "html",
+              attrs: { [RECORD_DOCUMENT_ATTRIBUTE]: "bsk:user@example.com" },
+              rect: null,
+              paintOrder: 0,
+              position: "static",
+              pointerEvents: "auto",
+            },
+          ],
+        },
+      ],
+      rendered: { text: '@vom 1\nRootWebArea "Example"', refs: [], truncated: false },
+    });
+
+    expect(result.frames).toEqual([{ frameId: "root", target: { tabId: 4 } }]);
+    expect(JSON.stringify(result)).not.toContain("user@example.com");
+  });
+});
@@ -0,0 +1,782 @@
+import { isVomReferenceNode, renderVom } from "@browser-skill/vom";
+import { describe, expect, it } from "vitest";
+import type { CapturedNode } from "../capture";
+import type { FrameDocument } from "../frame-document";
+import { buildSemanticVomScene, type SemanticAxNode } from "../semantic-graph";
+
+function dom(
+  backendNodeId: number,
+  parentBackendNodeId: number | null,
+  tag: string,
+  attrs: Record<string, string> = {},
+  textContent?: string,
+): CapturedNode {
+  return {
+    backendNodeId,
+    parentBackendNodeId,
+    tag,
+    attrs,
+    rect: { x: 0, y: 0, w: 100, h: 30 },
+    paintOrder: backendNodeId,
+    position: "static",
+    pointerEvents: "auto",
+    ...(textContent ? { textContent } : {}),
+  };
+}
+
+function document(
+  frameId: string,
+  axNodes: SemanticAxNode[],
+  domNodes: CapturedNode[],
+  frame?: Pick<FrameDocument<SemanticAxNode>, "parentFrameId" | "ownerBackendNodeId">,
+): FrameDocument<SemanticAxNode> {
+  return {
+    frameId,
+    contextScopeId: frameId,
+    target: { tabId: 1 },
+    axNodes,
+    domNodes,
+    ...frame,
+  };
+}
+
+describe("semantic VOM graph", () => {
+  it("preserves backend-less AX structure without making it referenceable", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["toolbar"],
+            },
+            {
+              nodeId: "toolbar",
+              parentId: "root",
+              role: { type: "role", value: "toolbar" },
+              name: { type: "computedString", value: "Formatting" },
+              childIds: ["bold", "italic"],
+            },
+            {
+              nodeId: "bold",
+              parentId: "toolbar",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Bold" },
+            },
+            {
+              nodeId: "italic",
+              parentId: "toolbar",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Italic" },
+            },
+          ],
+          [dom(1, null, "body"), dom(2, 1, "button"), dom(3, 1, "button")],
+        ),
+      ],
+    });
+
+    const toolbar = scene.nodes.find((node) => node.role === "toolbar");
+    const buttons = scene.nodes.filter((node) => node.role === "button");
+    expect(toolbar).toEqual(expect.objectContaining({ name: "Formatting", referenceable: false }));
+    expect(buttons.map((node) => node.parentId)).toEqual([toolbar?.id, toolbar?.id]);
+    expect(toolbar && isVomReferenceNode(toolbar)).toBe(false);
+    expect(renderVom(scene).refs.map((ref) => ref.backendNodeId)).toEqual([2, 3]);
+  });
+
+  it("resolves missing AX names through one DOM naming pipeline", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["labelled", "titled", "text"],
+            },
+            {
+              nodeId: "labelled",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "button" },
+            },
+            {
+              nodeId: "titled",
+              parentId: "root",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "button" },
+            },
+            {
+              nodeId: "text",
+              parentId: "root",
+              backendDOMNodeId: 4,
+              role: { type: "role", value: "button" },
+            },
+          ],
+          [
+            dom(1, null, "body"),
+            dom(2, 1, "button", { "aria-label": "Add row" }),
+            dom(3, 1, "button", { title: "Settings" }),
+            dom(4, 1, "button"),
+            dom(5, 4, "span", {}, "Save"),
+          ],
+        ),
+      ],
+    });
+
+    expect(scene.nodes.filter((node) => node.role === "button").map((node) => node.name)).toEqual([
+      "Add row",
+      "Settings",
+      "Save",
+    ]);
+  });
+
+  it("aggregates AX text at the semantic text frontier", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["covered", "inline-only", "repeated", "labelled"],
+            },
+            {
+              nodeId: "covered",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "paragraph" },
+              childIds: ["covered-static"],
+            },
+            {
+              nodeId: "covered-static",
+              parentId: "covered",
+              role: { type: "role", value: "StaticText" },
+              name: { type: "computedString", value: "Covered text" },
+              childIds: ["covered-inline"],
+            },
+            {
+              nodeId: "covered-inline",
+              parentId: "covered-static",
+              role: { type: "role", value: "InlineTextBox" },
+              name: { type: "computedString", value: "Covered text" },
+            },
+            {
+              nodeId: "inline-only",
+              parentId: "root",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "paragraph" },
+              childIds: ["inline-leaf"],
+            },
+            {
+              nodeId: "inline-leaf",
+              parentId: "inline-only",
+              role: { type: "role", value: "InlineTextBox" },
+              name: { type: "computedString", value: "Inline fallback" },
+            },
+            {
+              nodeId: "repeated",
+              parentId: "root",
+              backendDOMNodeId: 4,
+              role: { type: "role", value: "paragraph" },
+              childIds: ["first-go", "second-go"],
+            },
+            {
+              nodeId: "first-go",
+              parentId: "repeated",
+              role: { type: "role", value: "StaticText" },
+              name: { type: "computedString", value: "Go" },
+            },
+            {
+              nodeId: "second-go",
+              parentId: "repeated",
+              role: { type: "role", value: "StaticText" },
+              name: { type: "computedString", value: "Go" },
+            },
+            {
+              nodeId: "labelled",
+              parentId: "root",
+              backendDOMNodeId: 5,
+              role: { type: "role", value: "button" },
+              childIds: ["visible-label"],
+            },
+            {
+              nodeId: "visible-label",
+              parentId: "labelled",
+              role: { type: "role", value: "StaticText" },
+              name: { type: "computedString", value: "Visible text" },
+            },
+          ],
+          [
+            dom(1, null, "body"),
+            dom(2, 1, "p"),
+            dom(3, 1, "p"),
+            dom(4, 1, "p"),
+            dom(5, 1, "button", { "aria-label": "Explicit action" }),
+          ],
+        ),
+      ],
+    });
+
+    expect(scene.nodes.find((node) => node.backendNodeId === 2)?.name).toBe("Covered text");
+    expect(scene.nodes.find((node) => node.backendNodeId === 3)?.name).toBe("Inline fallback");
+    expect(scene.nodes.find((node) => node.backendNodeId === 4)?.name).toBe("Go Go");
+    expect(scene.nodes.find((node) => node.backendNodeId === 5)?.name).toBe("Explicit action");
+    expect(renderVom(scene).text).not.toContain("Covered text Covered text");
+  });
+
+  it("uses stable identifiers only as a final name fallback", () => {
+    const base = document(
+      "main",
+      [
+        {
+          nodeId: "root",
+          backendDOMNodeId: 1,
+          role: { type: "role", value: "RootWebArea" },
+          childIds: ["fallback", "labelled", "container"],
+        },
+        {
+          nodeId: "fallback",
+          parentId: "root",
+          backendDOMNodeId: 2,
+          role: { type: "role", value: "button" },
+        },
+        {
+          nodeId: "labelled",
+          parentId: "root",
+          backendDOMNodeId: 3,
+          role: { type: "role", value: "button" },
+          name: { type: "computedString", value: "Localized name" },
+        },
+        {
+          nodeId: "container",
+          parentId: "root",
+          backendDOMNodeId: 4,
+          role: { type: "role", value: "generic" },
+        },
+      ],
+      [
+        dom(1, null, "body"),
+        dom(2, 1, "button", { "data-test-id": "toolInsertRecord" }),
+        dom(3, 1, "button", { id: "toolIgnoredFallback" }),
+        dom(4, 1, "div", { id: "toolbarContainer" }),
+      ],
+    );
+    const staticScene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [base],
+    });
+    const enrichedScene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [base],
+      supplementalNames: new Map([["main\u00002", "插入行"]]),
+    });
+
+    expect(staticScene.nodes.find((node) => node.backendNodeId === 2)?.name).toBe("Insert record");
+    expect(staticScene.nodes.find((node) => node.backendNodeId === 3)?.name).toBe("Localized name");
+    expect(staticScene.nodes.find((node) => node.backendNodeId === 4)?.name).toBeUndefined();
+    expect(enrichedScene.nodes.find((node) => node.backendNodeId === 2)?.name).toBe("插入行");
+    expect(enrichedScene.nodes.find((node) => node.backendNodeId === 3)?.name).toBe(
+      "Localized name",
+    );
+  });
+
+  it("isolates equal backend node ids in sibling frames", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 1000, height: 800 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["owner-a", "owner-b"],
+            },
+            {
+              nodeId: "owner-a",
+              parentId: "root",
+              backendDOMNodeId: 10,
+              role: { type: "role", value: "Iframe" },
+            },
+            {
+              nodeId: "owner-b",
+              parentId: "root",
+              backendDOMNodeId: 20,
+              role: { type: "role", value: "Iframe" },
+            },
+          ],
+          [dom(1, null, "body"), dom(10, 1, "iframe"), dom(20, 1, "iframe")],
+        ),
+        document(
+          "frame-a",
+          [
+            {
+              nodeId: "button-a",
+              backendDOMNodeId: 5,
+              role: { type: "role", value: "button" },
+              childIds: ["text-a"],
+            },
+            {
+              nodeId: "text-a",
+              parentId: "button-a",
+              role: { type: "role", value: "StaticText" },
+              name: { type: "computedString", value: "Accept" },
+              childIds: ["inline-a"],
+            },
+            {
+              nodeId: "inline-a",
+              parentId: "text-a",
+              role: { type: "role", value: "InlineTextBox" },
+              name: { type: "computedString", value: "Accept" },
+            },
+          ],
+          [dom(5, null, "button")],
+          { parentFrameId: "main", ownerBackendNodeId: 10 },
+        ),
+        document(
+          "frame-b",
+          [
+            {
+              nodeId: "button-b",
+              backendDOMNodeId: 5,
+              role: { type: "role", value: "button" },
+              childIds: ["text-b"],
+            },
+            {
+              nodeId: "text-b",
+              parentId: "button-b",
+              role: { type: "role", value: "StaticText" },
+              name: { type: "computedString", value: "Decline" },
+              childIds: ["inline-b"],
+            },
+            {
+              nodeId: "inline-b",
+              parentId: "text-b",
+              role: { type: "role", value: "InlineTextBox" },
+              name: { type: "computedString", value: "Decline" },
+            },
+          ],
+          [dom(5, null, "button")],
+          { parentFrameId: "main", ownerBackendNodeId: 20 },
+        ),
+      ],
+    });
+
+    const frameButtons = scene.nodes.filter((node) => node.backendNodeId === 5);
+    const owners = new Map(
+      scene.nodes
+        .filter((node) => node.backendNodeId === 10 || node.backendNodeId === 20)
+        .map((node) => [node.backendNodeId, node.id]),
+    );
+    expect(frameButtons.map((node) => node.frameId)).toEqual(["frame-a", "frame-b"]);
+    expect(frameButtons.map((node) => node.name)).toEqual(["Accept", "Decline"]);
+    expect(frameButtons.map((node) => node.parentId)).toEqual([owners.get(10), owners.get(20)]);
+    expect(renderVom(scene).refs.map((ref) => [ref.frameId, ref.backendNodeId])).toEqual([
+      ["frame-a", 5],
+      ["frame-b", 5],
+    ]);
+  });
+
+  it("requires render evidence before promoting DOM fallback semantics", () => {
+    const hiddenOwner = {
+      ...dom(10, 1, "iframe", { hidden: "" }),
+      rect: null,
+      localRect: null,
+      rendered: false,
+    };
+    const hiddenButton = {
+      ...dom(2, 1, "button", { "aria-label": "Hidden action" }),
+      rendered: false,
+    };
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+            },
+          ],
+          [dom(1, null, "body"), hiddenButton, hiddenOwner],
+        ),
+        document("hidden-frame", [], [dom(20, null, "button", {}, "Frame action")], {
+          parentFrameId: "main",
+          ownerBackendNodeId: 10,
+        }),
+      ],
+    });
+
+    expect(scene.nodes.some((node) => node.backendNodeId === 2)).toBe(false);
+    expect(scene.nodes.some((node) => node.backendNodeId === 10)).toBe(false);
+    expect(scene.nodes.some((node) => node.frameId === "hidden-frame")).toBe(false);
+    expect(renderVom(scene).refs).toEqual([]);
+  });
+
+  it("retains rendered DOM fallback controls when AX semantics are unavailable", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [],
+          [dom(1, null, "body"), { ...dom(2, 1, "button", {}, "Save"), rendered: true }],
+        ),
+      ],
+    });
+
+    expect(renderVom(scene).refs).toEqual([
+      expect.objectContaining({ backendNodeId: 2, role: "button", name: "Save" }),
+    ]);
+  });
+
+  it("lets explicit DOM structure override ignored AX metadata", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["toolbar"],
+            },
+            {
+              nodeId: "toolbar",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              ignored: true,
+              role: { type: "role", value: "generic" },
+              childIds: ["wrapper"],
+            },
+            {
+              nodeId: "wrapper",
+              parentId: "toolbar",
+              backendDOMNodeId: 5,
+              role: { type: "role", value: "generic" },
+              childIds: ["bold", "italic"],
+            },
+            {
+              nodeId: "bold",
+              parentId: "wrapper",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Bold" },
+            },
+            {
+              nodeId: "italic",
+              parentId: "wrapper",
+              backendDOMNodeId: 4,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Italic" },
+            },
+          ],
+          [
+            dom(1, null, "body"),
+            dom(2, 1, "div", { role: "toolbar" }),
+            dom(5, 2, "div"),
+            dom(3, 5, "button"),
+            dom(4, 5, "button"),
+          ],
+        ),
+      ],
+    });
+
+    const toolbar = scene.nodes.find((node) => node.backendNodeId === 2);
+    const buttons = scene.nodes.filter((node) => [3, 4].includes(node.backendNodeId ?? -1));
+    expect(toolbar).toEqual(expect.objectContaining({ role: "toolbar" }));
+    expect(toolbar && isVomReferenceNode(toolbar)).toBe(false);
+    expect(scene.nodes.some((node) => node.role === "group")).toBe(false);
+    expect(buttons.map((node) => node.parentId)).toEqual([toolbar?.id, toolbar?.id]);
+  });
+
+  it("infers an unnamed group only from independent interaction branches", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["wrapper"],
+            },
+            {
+              nodeId: "wrapper",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "generic" },
+              childIds: ["first", "second"],
+            },
+            {
+              nodeId: "first",
+              parentId: "wrapper",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "First" },
+            },
+            {
+              nodeId: "second",
+              parentId: "wrapper",
+              backendDOMNodeId: 4,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Second" },
+            },
+          ],
+          [dom(1, null, "body"), dom(2, 1, "div"), dom(3, 2, "button"), dom(4, 2, "button")],
+        ),
+      ],
+    });
+
+    const group = scene.nodes.find((node) => node.backendNodeId === 2);
+    const buttons = scene.nodes.filter((node) => [3, 4].includes(node.backendNodeId ?? -1));
+    expect(group).toEqual(expect.objectContaining({ role: "group" }));
+    expect(group?.name).toBeUndefined();
+    expect(group && isVomReferenceNode(group)).toBe(false);
+    expect(buttons.map((node) => node.parentId)).toEqual([group?.id, group?.id]);
+
+    const rendered = renderVom(scene);
+    const lines = rendered.text.split("\n");
+    const groupLine = lines.findIndex((line) => line.trim() === "group");
+    expect(groupLine).toBeGreaterThanOrEqual(0);
+    for (const ref of rendered.refs) {
+      expect(ref.line).toBeGreaterThan(groupLine);
+      expect(lines[ref.line]).toMatch(/^\s+@e\d+ button/);
+    }
+  });
+
+  it("never promotes a form value into its semantic name through supplemental evidence", () => {
+    const secret = "user@example.com";
+    const input = {
+      ...dom(2, 1, "input", { type: "email" }),
+      formValue: secret,
+      formDefaultValue: "",
+      formState: "filled" as const,
+    };
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      supplementalNames: new Map([["main\u00002", secret]]),
+      identifierFallback: false,
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["email"],
+            },
+            {
+              nodeId: "email",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "textbox" },
+              value: { value: secret },
+            },
+          ],
+          [dom(1, null, "body"), input],
+        ),
+      ],
+    });
+
+    const field = scene.nodes.find((node) => node.backendNodeId === 2);
+    expect(field?.name).toBeUndefined();
+    const rendered = renderVom(scene, { redactValues: true });
+    expect(rendered.text).toContain("•••");
+    expect(JSON.stringify(rendered)).not.toContain(secret);
+  });
+
+  it("keeps uncertain single-branch wrappers flat", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["wrapper"],
+            },
+            {
+              nodeId: "wrapper",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "generic" },
+              childIds: ["button"],
+            },
+            {
+              nodeId: "button",
+              parentId: "wrapper",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Only action" },
+            },
+          ],
+          [dom(1, null, "body"), dom(2, 1, "div"), dom(3, 2, "button")],
+        ),
+      ],
+    });
+
+    expect(scene.nodes.some((node) => node.role === "group")).toBe(false);
+    expect(scene.nodes.find((node) => node.backendNodeId === 3)?.parentId).toBe(
+      scene.nodes.find((node) => node.backendNodeId === 1)?.id,
+    );
+  });
+
+  it("does not infer across mixed content boundaries", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["wrapper"],
+            },
+            {
+              nodeId: "wrapper",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "generic" },
+              childIds: ["first", "second", "paragraph"],
+            },
+            {
+              nodeId: "first",
+              parentId: "wrapper",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "First" },
+            },
+            {
+              nodeId: "second",
+              parentId: "wrapper",
+              backendDOMNodeId: 4,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Second" },
+            },
+            {
+              nodeId: "paragraph",
+              parentId: "wrapper",
+              backendDOMNodeId: 5,
+              role: { type: "role", value: "paragraph" },
+            },
+          ],
+          [
+            dom(1, null, "body"),
+            dom(2, 1, "div"),
+            dom(3, 2, "button"),
+            dom(4, 2, "button"),
+            dom(5, 2, "p", {}, "Description"),
+          ],
+        ),
+      ],
+    });
+
+    expect(scene.nodes.some((node) => node.role === "group")).toBe(false);
+  });
+
+  it("keeps only the innermost reliable inferred group", () => {
+    const scene = buildSemanticVomScene({
+      viewport: { width: 800, height: 600 },
+      rootFrameId: "main",
+      documents: [
+        document(
+          "main",
+          [
+            {
+              nodeId: "root",
+              backendDOMNodeId: 1,
+              role: { type: "role", value: "RootWebArea" },
+              childIds: ["outer"],
+            },
+            {
+              nodeId: "outer",
+              parentId: "root",
+              backendDOMNodeId: 2,
+              role: { type: "role", value: "generic" },
+              childIds: ["inner", "third"],
+            },
+            {
+              nodeId: "inner",
+              parentId: "outer",
+              backendDOMNodeId: 3,
+              role: { type: "role", value: "generic" },
+              childIds: ["first", "second"],
+            },
+            {
+              nodeId: "first",
+              parentId: "inner",
+              backendDOMNodeId: 4,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "First" },
+            },
+            {
+              nodeId: "second",
+              parentId: "inner",
+              backendDOMNodeId: 5,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Second" },
+            },
+            {
+              nodeId: "third",
+              parentId: "outer",
+              backendDOMNodeId: 6,
+              role: { type: "role", value: "button" },
+              name: { type: "computedString", value: "Third" },
+            },
+          ],
+          [
+            dom(1, null, "body"),
+            dom(2, 1, "div"),
+            dom(3, 2, "div"),
+            dom(4, 3, "button"),
+            dom(5, 3, "button"),
+            dom(6, 2, "button"),
+          ],
+        ),
+      ],
+    });
+
+    const groups = scene.nodes.filter((node) => node.role === "group");
+    expect(groups.map((node) => node.backendNodeId)).toEqual([3]);
+    expect(scene.nodes.find((node) => node.backendNodeId === 6)?.parentId).not.toBe(groups[0]?.id);
+  });
+});
@@ -1,16 +1,17 @@
 // CDP capture adapter: DOMSnapshot.captureSnapshot + Page.getLayoutMetrics
 // → CapturedNode[] + Viewport. This is the ONLY VOM module that touches
 // raw CDP. The captureSnapshot reply is columnar (parallel arrays + a
-// shared string table); we request exactly three computed styles so the
-// `styles` columns are [position, pointer-events, cursor] in that order.
+// shared string table); requested computed styles are decoded through
+// STYLE_COL so capture and visibility policy share one explicit contract.

 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";
+import { clearHover, ProbeBudget, waitForHover } from "./hover-perception";

-const REQUESTED_STYLES = ["position", "pointer-events", "cursor"] as const;
+const REQUESTED_STYLES = ["position", "pointer-events", "cursor", "visibility", "opacity"] as const;
 const STYLE_COL = Object.fromEntries(
  REQUESTED_STYLES.map((name, index) => [name, index]),
 ) as Record<(typeof REQUESTED_STYLES)[number], number>;
@@ -38,6 +39,12 @@ export interface CapturedNode {
   * `textContent`: the live parser always sets it, hand-built fixtures may not.
   */
  cursor?: string;
+  /**
+   * Whether the live DOM snapshot provides a painted, non-hidden box for this
+   * node. Semantic resolution uses this only for DOM fallback nodes; AX-backed
+   * nodes remain authoritative even when they are outside the viewport.
+   */
+  rendered?: boolean;
  textContent?: string;
  formState?: "empty" | "filled" | "default";
  formValue?: string;
@@ -64,14 +71,11 @@ export interface CapturedViewModel {
  /** Explicit DOMSnapshot frame ancestry; never inferred from backend node ids. */
  frameParentIds?: Map<string, string>;
  rootFrameId?: string;
-  surfaceProbes?: CapturedSurfaceProbe[];
  /** Backend node ids belonging to the agent overlay host + its shadow subtree. */
  excludedBackendNodeIds: Set<number>;
 }

 export interface CaptureViewModelOptions {
-  conditionalSurfaceProbe?: boolean;
-  hoverProbeBypassOverlay?: (tabId: number, enabled: boolean) => Promise<void>;
  signal?: AbortSignal;
 }

@@ -361,7 +365,16 @@ function collectBackendIdsFromDomNode(node: CdpDomNode | undefined, out: Set<num
  }
 }

-const MAX_HOVER_PROBE_MS = 2_000;
+/**
+ * Ceiling for the whole hover-surface phase.
+ *
+ * The previous 2000 was only a floor: the loop checked elapsed time at the top,
+ * so a candidate could start with 1ms left and still run its two settle
+ * windows, pushing real cost to ~2.6s. This is that true ceiling, now actually
+ * enforced by an up-front affordability check, so the same number of candidates
+ * get probed under a bound that no longer lies.
+ */
+const MAX_HOVER_PROBE_MS = 2_600;
 const MAX_HOVER_TRIGGERS = 6;
 const MAX_HOVER_SURFACES = 3;
 const HOVER_SETTLE_MS = 300;
@@ -460,36 +473,6 @@ function hoverStateExpression(): string {
  })()`;
 }

-async function wait(ms: number, signal?: AbortSignal): Promise<void> {
-  throwIfAborted(signal);
-  await new Promise<void>((resolve, reject) => {
-    const timer = setTimeout(() => {
-      signal?.removeEventListener("abort", onAbort);
-      resolve();
-    }, ms);
-    const onAbort = () => {
-      clearTimeout(timer);
-      signal?.removeEventListener("abort", onAbort);
-      reject(captureAbortError());
-    };
-    signal?.addEventListener("abort", onAbort, { once: true });
-  });
-}
-
-async function clearHover(cdp: CdpRunner, tabId: number): Promise<void> {
-  await cdp
-    .send(tabId, "Input.dispatchMouseEvent", {
-      type: "mouseMoved",
-      x: -10,
-      y: -10,
-    })
-    .catch(() =>
-      cdp.send(tabId, "Input.dispatchMouseEvent", { type: "mouseMoved", x: 0, y: 0 }).catch(() => {
-        // best effort
-      }),
-    );
-}
-
 function capturedText(node: CapturedNode): string | undefined {
  const value =
    node.attrs["aria-label"] ?? node.attrs.title ?? node.attrs.alt ?? node.textContent ?? "";
@@ -637,13 +620,35 @@ function confidenceForHover(
  return "low";
 }

-async function probeHoverSurfaces(
+/**
+ * One candidate costs two settle windows (baseline + post-hover) plus a few
+ * CDP round trips. Used to decide whether the next candidate still fits the
+ * budget before paying for it.
+ */
+const HOVER_CANDIDATE_COST_MS = HOVER_SETTLE_MS * 2;
+
+export interface HoverSurfaceProbeOptions {
+  signal?: AbortSignal;
+}
+
+/**
+ * Hovers a bounded set of likely menu triggers and reports the sub-items each
+ * one reveals.
+ *
+ * Runs after DOM *and* accessibility capture. Hovering can open menus and
+ * change layout, so probing between the two captures would leave the DOM half
+ * of an observation describing the page before the change and the AX half
+ * describing it after.
+ *
+ * The caller owns the overlay bypass span (see `withOverlayBypass`).
+ */
+export async function probeHoverSurfaces(
  cdp: CdpRunner,
  tabId: number,
  nodes: CapturedNode[],
-  options: CaptureViewModelOptions,
+  options: HoverSurfaceProbeOptions = {},
 ): Promise<CapturedSurfaceProbe[]> {
-  const started = Date.now();
+  const budget = new ProbeBudget(MAX_HOVER_PROBE_MS);
  try {
    throwIfAborted(options.signal);
    const cssScan = await cdp.send<RuntimeEvaluateReply>(tabId, "Runtime.evaluate", {
@@ -658,60 +663,54 @@ async function probeHoverSurfaces(
    const results: CapturedSurfaceProbe[] = [];
    const seen = new Set<number>();
    throwIfAborted(options.signal);
-    await options.hoverProbeBypassOverlay?.(tabId, true).catch(() => undefined);
-    try {
+    for (const candidate of candidates.slice(0, MAX_HOVER_TRIGGERS)) {
      throwIfAborted(options.signal);
-      for (const candidate of candidates.slice(0, MAX_HOVER_TRIGGERS)) {
+      if (!budget.canAfford(HOVER_CANDIDATE_COST_MS)) break;
+      if (results.length >= MAX_HOVER_SURFACES) break;
+      if (seen.has(candidate.backendNodeId)) continue;
+      try {
+        await clearHover(cdp, tabId);
        throwIfAborted(options.signal);
-        if (Date.now() - started > MAX_HOVER_PROBE_MS) break;
-        if (results.length >= MAX_HOVER_SURFACES) break;
-        if (seen.has(candidate.backendNodeId)) continue;
-        try {
-          await clearHover(cdp, tabId);
-          throwIfAborted(options.signal);
-          await wait(HOVER_SETTLE_MS, options.signal);
-          const baselineReply = await cdp.send<RuntimeEvaluateReply>(tabId, "Runtime.evaluate", {
-            expression: hoverStateExpression(),
-            returnByValue: true,
-          });
-          throwIfAborted(options.signal);
-          const baselineItems = runtimeValue<HoverRuntimeItem[]>(baselineReply) ?? [];
+        await waitForHover(HOVER_SETTLE_MS, options.signal);
+        const baselineReply = await cdp.send<RuntimeEvaluateReply>(tabId, "Runtime.evaluate", {
+          expression: hoverStateExpression(),
+          returnByValue: true,
+        });
+        throwIfAborted(options.signal);
+        const baselineItems = runtimeValue<HoverRuntimeItem[]>(baselineReply) ?? [];

-          throwIfAborted(options.signal);
-          await cdp.send(tabId, "Input.dispatchMouseEvent", {
-            type: "mouseMoved",
-            x: candidate.x,
-            y: candidate.y,
-          });
-          throwIfAborted(options.signal);
-          await wait(HOVER_SETTLE_MS, options.signal);
-          const collected = await cdp.send<RuntimeEvaluateReply>(tabId, "Runtime.evaluate", {
-            expression: hoverStateExpression(),
-            returnByValue: true,
-          });
-          throwIfAborted(options.signal);
-          const subItems = diffHoverItems(
-            baselineItems,
-            runtimeValue<HoverRuntimeItem[]>(collected) ?? [],
-          );
-          if (subItems.length === 0) continue;
-          seen.add(candidate.backendNodeId);
-          results.push({
-            triggerBackendNodeId: candidate.backendNodeId,
-            triggerPoint: { x: candidate.x, y: candidate.y },
-            triggerAction: "hover",
-            subItems,
-            confidence: confidenceForHover(candidate, subItems),
-          });
-        } catch (error) {
-          if (isAbortError(error)) throw error;
-          continue;
-        } finally {
-          await clearHover(cdp, tabId);
-        }
+        throwIfAborted(options.signal);
+        await cdp.send(tabId, "Input.dispatchMouseEvent", {
+          type: "mouseMoved",
+          x: candidate.x,
+          y: candidate.y,
+        });
+        throwIfAborted(options.signal);
+        await waitForHover(HOVER_SETTLE_MS, options.signal);
+        const collected = await cdp.send<RuntimeEvaluateReply>(tabId, "Runtime.evaluate", {
+          expression: hoverStateExpression(),
+          returnByValue: true,
+        });
+        throwIfAborted(options.signal);
+        const subItems = diffHoverItems(
+          baselineItems,
+          runtimeValue<HoverRuntimeItem[]>(collected) ?? [],
+        );
+        if (subItems.length === 0) continue;
+        seen.add(candidate.backendNodeId);
+        results.push({
+          triggerBackendNodeId: candidate.backendNodeId,
+          triggerPoint: { x: candidate.x, y: candidate.y },
+          triggerAction: "hover",
+          subItems,
+          confidence: confidenceForHover(candidate, subItems),
+        });
+      } catch (error) {
+        if (isAbortError(error)) throw error;
+        continue;
+      } finally {
+        await clearHover(cdp, tabId);
      }
-    } finally {
-      await options.hoverProbeBypassOverlay?.(tabId, false).catch(() => undefined);
    }
    return results;
  } catch (err) {
@@ -817,6 +816,8 @@ function parseDocumentNodes(
  const posCol = STYLE_COL.position;
  const peCol = STYLE_COL["pointer-events"];
  const cursorCol = STYLE_COL.cursor;
+  const visibilityCol = STYLE_COL.visibility;
+  const opacityCol = STYLE_COL.opacity;
  const inputValues = sparseIndexMap(dn.inputValue);
  const textValues = sparseIndexMap(dn.textValue);
  const checkedInputs = new Set(dn.inputChecked?.index ?? []);
@@ -861,6 +862,7 @@ function parseDocumentNodes(
    let position = "static";
    let pointerEvents = "auto";
    let cursor = "auto";
+    let rendered = false;
    const li = layoutByNode.get(n);
    if (li !== undefined) {
      const b = dl?.bounds?.[li];
@@ -881,6 +883,13 @@ function parseDocumentNodes(
      position = str(strings, styleRow[posCol]) || "static";
      pointerEvents = str(strings, styleRow[peCol]) || "auto";
      cursor = str(strings, styleRow[cursorCol]) || "auto";
+      const visibility = str(strings, styleRow[visibilityCol]) || "visible";
+      const opacity = str(strings, styleRow[opacityCol]) || "1";
+      rendered =
+        localRect !== null &&
+        visibility !== "hidden" &&
+        visibility !== "collapse" &&
+        (Number.parseFloat(opacity) || 0) > 0;
    }

    // Skip non-element nodes (#text, #cdata-section, etc.) — they carry no
@@ -916,6 +925,7 @@ function parseDocumentNodes(
      position,
      pointerEvents,
      cursor,
+      rendered,
      textContent,
      ...(formValue !== undefined ? { formValue } : {}),
      ...(tag === "input" || tag === "textarea"
@@ -1020,7 +1030,13 @@ export async function captureViewModel(
  options: CaptureViewModelOptions = {},
 ): Promise<CapturedViewModel> {
  throwIfAborted(options.signal);
-  const metrics = await cdp.send<LayoutMetricsReply>(tabId, "Page.getLayoutMetrics", {});
+  let metrics: LayoutMetricsReply = {};
+  try {
+    metrics = await cdp.send<LayoutMetricsReply>(tabId, "Page.getLayoutMetrics", {});
+  } catch (error) {
+    if (isAbortError(error)) throw error;
+    console.debug("[bsk capture] layout metrics unavailable", error);
+  }
  throwIfAborted(options.signal);
  const dpr = devicePixelRatio(metrics);
  const vpSrc = metrics.cssLayoutViewport ?? metrics.layoutViewport ?? {};
@@ -1048,7 +1064,6 @@ export async function captureViewModel(
      nodes: [],
      viewport,
      iframeNodes: new Map(),
-      surfaceProbes: [],
      excludedBackendNodeIds: new Set(),
    };
  }
@@ -1077,11 +1092,6 @@ export async function captureViewModel(
  await enrichFormControlStates(cdp, tabId, [nodes, ...iframeNodes.values()], options.signal);
  throwIfAborted(options.signal);

-  const surfaceProbes = options.conditionalSurfaceProbe
-    ? await probeHoverSurfaces(cdp, tabId, nodes, options)
-    : [];
-  throwIfAborted(options.signal);
-
  const frameNodes = new Map<string, CapturedNode[]>();
  if (topContext.frameId) frameNodes.set(topContext.frameId, nodes);
  for (const iframeFrameNodes of iframeNodes.values()) {
@@ -1102,7 +1112,6 @@ export async function captureViewModel(
    frameOwnerBackendNodeIds: frameParsed.frameOwnerBackendNodeIds,
    frameParentIds: frameParsed.frameParentIds,
    ...(topContext.frameId ? { rootFrameId: topContext.frameId } : {}),
-    surfaceProbes,
    excludedBackendNodeIds,
  };
 }
@@ -33,25 +33,19 @@ async function discoverFrameGraph(cdp: CdpRunner, tabId: number): Promise<CdpFra

 function transformFrameNodes(
  nodes: CapturedNode[],
-  projection: GeometryProjection,
+  projection: GeometryProjection | null,
 ): 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;
-    })(),
+    rect: projection
+      ? (() => {
+          const bounds = projectRectToViewport(node.rect, projection);
+          return bounds ? { x: bounds.x, y: bounds.y, w: bounds.width, h: bounds.height } : null;
+        })()
+      : 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,
@@ -65,14 +59,20 @@ async function captureMissingFrameDocuments(

  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;
+      let projection: GeometryProjection | null = null;
+      try {
+        projection = await resolveFrameProjection(cdp, graph, frame.frameId);
+      } catch (err) {
+        if (isAbortError(err)) throw err;
+        console.debug("[bsk observation] child frame geometry projection failed", {
+          frameId: frame.frameId,
+          err,
+        });
+      }
      const rootFrameId = child.rootFrameId ?? frame.frameId;
      const childFrames = child.frameNodes ?? new Map<string, CapturedNode[]>();
      if (!childFrames.has(rootFrameId)) childFrames.set(rootFrameId, child.nodes);
@@ -85,11 +85,13 @@ async function captureMissingFrameDocuments(
      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.ownerBackendNodeId !== undefined) {
+        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);
@@ -0,0 +1,125 @@
+import type { CdpRunner } from "../shared";
+
+function abortError(): Error {
+  const error = new Error("hover perception aborted");
+  error.name = "AbortError";
+  return error;
+}
+
+export async function waitForHover(ms: number, signal?: AbortSignal): Promise<void> {
+  if (signal?.aborted) throw abortError();
+  await new Promise<void>((resolve, reject) => {
+    const timer = setTimeout(() => {
+      signal?.removeEventListener("abort", onAbort);
+      resolve();
+    }, ms);
+    const onAbort = () => {
+      clearTimeout(timer);
+      signal?.removeEventListener("abort", onAbort);
+      reject(abortError());
+    };
+    signal?.addEventListener("abort", onAbort, { once: true });
+  });
+}
+
+export async function clearHover(cdp: CdpRunner, tabId: number): Promise<void> {
+  await cdp
+    .send(tabId, "Input.dispatchMouseEvent", {
+      type: "mouseMoved",
+      x: -10,
+      y: -10,
+    })
+    .catch(() =>
+      cdp.send(tabId, "Input.dispatchMouseEvent", { type: "mouseMoved", x: 0, y: 0 }).catch(() => {
+        // Best effort cleanup.
+      }),
+    );
+}
+
+/**
+ * Wall-clock budget for a probe phase.
+ *
+ * Callers ask whether the *next* candidate still fits before starting it,
+ * rather than checking elapsed time at the top of the loop. A top-of-loop
+ * check lets a candidate start with 1ms of budget left and then run to
+ * completion, overshooting by a full settle window.
+ */
+export class ProbeBudget {
+  private readonly startedAt = Date.now();
+
+  constructor(private readonly totalMs: number) {}
+
+  get elapsedMs(): number {
+    return Date.now() - this.startedAt;
+  }
+
+  /** True when a candidate costing `estimatedMs` still fits in the budget. */
+  canAfford(estimatedMs: number): boolean {
+    return this.elapsedMs + estimatedMs <= this.totalMs;
+  }
+}
+
+export type OverlayBypass = (tabId: number, enabled: boolean) => Promise<void>;
+
+export interface OverlayBypassScopeOptions {
+  /**
+   * Called when the overlay could not be restored. Defaults to `console.error`
+   * so a stuck-bypassed overlay is never silent; tests inject a spy.
+   */
+  onRestoreFailure?: (error: unknown) => void;
+}
+
+const overlayBypassDepth = new Map<number, number>();
+
+/**
+ * Runs `body` with the agent overlay bypassed, restoring it afterwards.
+ *
+ * Reference counted per tab so nested probe phases share a single bypass span
+ * instead of toggling the overlay once per phase. Restore failures are
+ * reported rather than swallowed, and the depth is released even when restore
+ * throws so a failure cannot pin the overlay off for the tab's lifetime.
+ */
+export async function withOverlayBypass<T>(
+  bypass: OverlayBypass | undefined,
+  tabId: number,
+  body: () => Promise<T>,
+  options: OverlayBypassScopeOptions = {},
+): Promise<T> {
+  if (!bypass) return body();
+
+  const depth = overlayBypassDepth.get(tabId) ?? 0;
+  overlayBypassDepth.set(tabId, depth + 1);
+  if (depth === 0) {
+    try {
+      await bypass(tabId, true);
+    } catch (error) {
+      // Failing to hide the overlay only risks probing our own UI, so continue.
+      console.debug("[bsk hover] overlay bypass could not be enabled", error);
+    }
+  }
+
+  try {
+    return await body();
+  } finally {
+    const current = overlayBypassDepth.get(tabId) ?? 1;
+    if (current <= 1) {
+      overlayBypassDepth.delete(tabId);
+      try {
+        await bypass(tabId, false);
+      } catch (error) {
+        (options.onRestoreFailure ?? defaultRestoreFailure)(error);
+      }
+    } else {
+      overlayBypassDepth.set(tabId, current - 1);
+    }
+  }
+}
+
+function defaultRestoreFailure(error: unknown): void {
+  console.error("[bsk hover] agent overlay could not be restored after probing", error);
+}
+
+/** Test seam: drops any bypass depth left behind by a crashed probe. */
+export function resetOverlayBypassDepth(): void {
+  overlayBypassDepth.clear();
+}
@@ -0,0 +1,307 @@
+import { isVomReferenceNode } from "@browser-skill/vom";
+import { type CdpRunner, sendToCdpTarget } from "../shared";
+import type { FrameDocument, FrameOwnedAxNode } from "./frame-document";
+import { clearHover, ProbeBudget, waitForHover } from "./hover-perception";
+import { stableIdentifierName } from "./semantic-graph/name-evidence";
+import { frameBackendKey, type ResolvedSemanticGraph } from "./semantic-graph/types";
+
+const MAX_TOOLTIP_CANDIDATES = 8;
+const MAX_TOOLTIP_PROBE_MS = 2_400;
+const TOOLTIP_SETTLE_MS = 250;
+const CACHE_TTL_MS = 5 * 60_000;
+/**
+ * Misses expire sooner than hits: a control that gains a tooltip once the app
+ * finishes booting should still be discoverable, but not at the cost of
+ * re-probing every unlabelled control on every observation.
+ */
+const MISS_CACHE_TTL_MS = 60_000;
+const MAX_CACHE_ENTRIES = 500;
+const FORM_CONTROL_TAGS = new Set(["input", "select", "textarea"]);
+
+interface TooltipCacheEntry {
+  /** `null` records "probed, revealed no tooltip" so the miss is not re-paid. */
+  name: string | null;
+  expiresAt: number;
+}
+
+interface TooltipCandidate<T extends FrameOwnedAxNode> {
+  document: FrameDocument<T>;
+  backendNodeId: number;
+  x: number;
+  y: number;
+  stableIdentifier: boolean;
+}
+
+export interface TooltipNameProbeOptions {
+  signal?: AbortSignal;
+}
+
+const tooltipCache = new Map<string, TooltipCacheEntry>();
+
+function cacheKey<T extends FrameOwnedAxNode>(
+  document: FrameDocument<T>,
+  backendNodeId: number,
+): string {
+  return `${document.target.tabId}\u0000${document.frameId}\u0000${document.url ?? ""}\u0000${backendNodeId}`;
+}
+
+/** Returns the cache entry, or `undefined` when this control was never probed. */
+function cachedEntry<T extends FrameOwnedAxNode>(
+  document: FrameDocument<T>,
+  backendNodeId: number,
+): TooltipCacheEntry | undefined {
+  const key = cacheKey(document, backendNodeId);
+  const entry = tooltipCache.get(key);
+  if (!entry) return undefined;
+  if (entry.expiresAt <= Date.now()) {
+    tooltipCache.delete(key);
+    return undefined;
+  }
+  return entry;
+}
+
+function storeName<T extends FrameOwnedAxNode>(
+  document: FrameDocument<T>,
+  backendNodeId: number,
+  name: string | null,
+): void {
+  if (tooltipCache.size >= MAX_CACHE_ENTRIES) {
+    const oldest = tooltipCache.keys().next().value;
+    if (oldest !== undefined) tooltipCache.delete(oldest);
+  }
+  tooltipCache.set(cacheKey(document, backendNodeId), {
+    name,
+    expiresAt: Date.now() + (name === null ? MISS_CACHE_TTL_MS : CACHE_TTL_MS),
+  });
+}
+
+function tooltipCollectorFunction(): string {
+  return `function() {
+    const ownRoot = this && typeof this.getRootNode === "function" ? this.getRootNode() : null;
+    const roots = ownRoot && ownRoot !== document ? [ownRoot, document] : [document];
+    const items = [];
+    const seen = new Set();
+    for (const root of roots) {
+      for (const el of Array.from(root.querySelectorAll("[role='tooltip']"))) {
+        const style = getComputedStyle(el);
+        const rect = el.getBoundingClientRect();
+        if (rect.width <= 0 || rect.height <= 0) continue;
+        if (style.display === "none" || style.visibility === "hidden" || style.opacity === "0") continue;
+        const text = String(el.getAttribute("aria-label") || el.getAttribute("title") || el.textContent || "")
+          .replace(/\\s+/g, " ")
+          .trim();
+        if (!text || text.length > 160 || seen.has(text)) continue;
+        seen.add(text);
+        items.push(text);
+      }
+    }
+    return items.slice(0, 20);
+  }`;
+}
+
+function cleanTooltipDiff(before: string[], after: string[]): string | undefined {
+  const existing = new Set(before.map((value) => value.toLowerCase()));
+  const added = [...new Set(after.map((value) => value.replace(/\s+/g, " ").trim()))].filter(
+    (value) => value && !existing.has(value.toLowerCase()),
+  );
+  return added.length === 1 ? added[0] : undefined;
+}
+
+function candidates<T extends FrameOwnedAxNode>(
+  documents: FrameDocument<T>[],
+  graph: ResolvedSemanticGraph,
+): TooltipCandidate<T>[] {
+  const documentByFrame = new Map(documents.map((document) => [document.frameId, document]));
+  const byFrame = new Map<string, TooltipCandidate<T>[]>();
+  for (const node of graph.nodes.values()) {
+    if (
+      node.vom.name ||
+      FORM_CONTROL_TAGS.has(node.dom?.tag.toLowerCase() ?? "") ||
+      !node.referenceable ||
+      node.backendNodeId === undefined ||
+      !isVomReferenceNode({
+        ...node.vom,
+        id: 0,
+        parentId: null,
+        backendNodeId: node.backendNodeId,
+        frameId: node.frameId,
+        referenceable: true,
+      })
+    ) {
+      continue;
+    }
+    const document = documentByFrame.get(node.frameId);
+    const rect = node.dom?.rect;
+    if (!document || !rect || rect.w <= 0 || rect.h <= 0) continue;
+    if (
+      rect.x + rect.w <= 0 ||
+      rect.y + rect.h <= 0 ||
+      rect.x >= graph.viewport.width ||
+      rect.y >= graph.viewport.height
+    ) {
+      continue;
+    }
+    if (
+      node.vom.disabled ||
+      node.vom.inert ||
+      node.vom.pointerEvents === "none" ||
+      node.vom.sensitive
+    ) {
+      continue;
+    }
+    const frameCandidates = byFrame.get(node.frameId) ?? [];
+    frameCandidates.push({
+      document,
+      backendNodeId: node.backendNodeId,
+      x: (Math.max(0, rect.x) + Math.min(graph.viewport.width, rect.x + rect.w)) / 2,
+      y: (Math.max(0, rect.y) + Math.min(graph.viewport.height, rect.y + rect.h)) / 2,
+      stableIdentifier: stableIdentifierName(node.dom?.attrs ?? {}) !== undefined,
+    });
+    byFrame.set(node.frameId, frameCandidates);
+  }
+
+  const out: TooltipCandidate<T>[] = [];
+  for (const stableIdentifier of [true, false]) {
+    const queues = documents.map((document) =>
+      (byFrame.get(document.frameId) ?? []).filter(
+        (candidate) => candidate.stableIdentifier === stableIdentifier,
+      ),
+    );
+    for (let index = 0; queues.some((queue) => index < queue.length); index += 1) {
+      for (const queue of queues) {
+        const candidate = queue[index];
+        if (candidate) out.push(candidate);
+      }
+    }
+  }
+  return out;
+}
+
+async function executionContextId<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+): Promise<number | undefined> {
+  const result = await sendToCdpTarget<{ executionContextId?: number }>(
+    cdp,
+    document.target,
+    "Page.createIsolatedWorld",
+    {
+      frameId: document.frameId,
+      worldName: "bsk-vom-tooltip",
+      grantUniveralAccess: false,
+    },
+  );
+  return result.executionContextId;
+}
+
+async function resolvedObjectId<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+  contextId: number,
+  backendNodeId: number,
+): Promise<string | undefined> {
+  const result = await sendToCdpTarget<{
+    object?: { objectId?: string };
+  }>(cdp, document.target, "DOM.resolveNode", {
+    backendNodeId,
+    executionContextId: contextId,
+  });
+  return result.object?.objectId;
+}
+
+async function tooltipTexts<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+  objectId: string,
+): Promise<string[]> {
+  const result = await sendToCdpTarget<{
+    result?: { value?: string[] };
+  }>(cdp, document.target, "Runtime.callFunctionOn", {
+    functionDeclaration: tooltipCollectorFunction(),
+    objectId,
+    returnByValue: true,
+  });
+  return result.result?.value ?? [];
+}
+
+async function releaseObject<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+  objectId: string,
+): Promise<void> {
+  await sendToCdpTarget(cdp, document.target, "Runtime.releaseObject", { objectId }).catch(
+    () => undefined,
+  );
+}
+
+export async function probeTooltipNames<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  tabId: number,
+  documents: FrameDocument<T>[],
+  graph: ResolvedSemanticGraph,
+  options: TooltipNameProbeOptions = {},
+): Promise<Map<string, string>> {
+  const names = new Map<string, string>();
+  const pending: TooltipCandidate<T>[] = [];
+  for (const candidate of candidates(documents, graph)) {
+    const cached = cachedEntry(candidate.document, candidate.backendNodeId);
+    if (cached) {
+      // A cached miss is still a decision: skip the control instead of re-probing.
+      if (cached.name !== null) {
+        names.set(
+          frameBackendKey(candidate.document.frameId, candidate.backendNodeId),
+          cached.name,
+        );
+      }
+    } else if (pending.length < MAX_TOOLTIP_CANDIDATES) {
+      pending.push(candidate);
+    }
+  }
+  if (pending.length === 0) return names;
+
+  const budget = new ProbeBudget(MAX_TOOLTIP_PROBE_MS);
+  const contexts = new Map<string, number>();
+  try {
+    for (const candidate of pending) {
+      if (options.signal?.aborted) throw new DOMException("observation aborted", "AbortError");
+      if (!budget.canAfford(TOOLTIP_SETTLE_MS)) break;
+      let objectId: string | undefined;
+      try {
+        let contextId = contexts.get(candidate.document.frameId);
+        if (contextId === undefined) {
+          contextId = await executionContextId(cdp, candidate.document);
+          if (contextId === undefined) continue;
+          contexts.set(candidate.document.frameId, contextId);
+        }
+        objectId = await resolvedObjectId(
+          cdp,
+          candidate.document,
+          contextId,
+          candidate.backendNodeId,
+        );
+        if (!objectId) continue;
+        await clearHover(cdp, tabId);
+        const before = await tooltipTexts(cdp, candidate.document, objectId);
+        await cdp.send(tabId, "Input.dispatchMouseEvent", {
+          type: "mouseMoved",
+          x: candidate.x,
+          y: candidate.y,
+        });
+        await waitForHover(TOOLTIP_SETTLE_MS, options.signal);
+        const after = await tooltipTexts(cdp, candidate.document, objectId);
+        const name = cleanTooltipDiff(before, after);
+        storeName(candidate.document, candidate.backendNodeId, name ?? null);
+        if (!name) continue;
+        names.set(frameBackendKey(candidate.document.frameId, candidate.backendNodeId), name);
+      } catch (error) {
+        if (error instanceof Error && error.name === "AbortError") throw error;
+      } finally {
+        if (objectId) await releaseObject(cdp, candidate.document, objectId);
+        await clearHover(cdp, tabId);
+      }
+    }
+  } finally {
+    await clearHover(cdp, tabId);
+  }
+  return names;
+}
@@ -1,5 +1,6 @@
 import type { Rect, RenderedRef, VomResult } from "@browser-skill/vom";
 import type { CdpTarget } from "@/browser-driver/frame-graph";
+import { readRecordingDocumentIdentity } from "@/shared/recording-document-identity";
 import type { CapturedSurfaceProbe } from "./capture";
 import type { CapturedFrameDocument, FrameAxNode } from "./frame-capture";

@@ -9,6 +10,8 @@ export interface CaptureVomFrame {
  target: CdpTarget;
  parentFrameId?: string;
  ownerBackendNodeId?: number;
+  /** BrowserSkill-generated identity for the recording agent in this Document. */
+  recordingDocumentId?: string;
 }

 /** Allowlisted geometry used to match a recorded action to a rendered ref. */
@@ -34,17 +37,36 @@ export interface CaptureVomObservationResult {
  frames: CaptureVomFrame[];
  matchNodes: CaptureVomMatchNode[];
  surfaceProbes?: CapturedSurfaceProbe[];
+  /**
+   * Whether this observation actively hovered the page, and whether that
+   * revealed content the static tree does not contain. Lets callers judge how
+   * far the page may have drifted from the returned snapshot.
+   */
+  hoverProbe?: HoverProbeReport;
+}
+
+export interface HoverProbeReport {
+  performed: boolean;
+  revealedContent: boolean;
 }

 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 }
-      : {}),
-  }));
+  return documents.map((document) => {
+    let recordingDocumentId: string | undefined;
+    for (const node of document.domNodes) {
+      recordingDocumentId = readRecordingDocumentIdentity(node.attrs);
+      if (recordingDocumentId) break;
+    }
+    return {
+      frameId: document.frameId,
+      target: document.target,
+      ...(document.parentFrameId ? { parentFrameId: document.parentFrameId } : {}),
+      ...(document.ownerBackendNodeId !== undefined
+        ? { ownerBackendNodeId: document.ownerBackendNodeId }
+        : {}),
+      ...(recordingDocumentId ? { recordingDocumentId } : {}),
+    };
+  });
 }

 function projectMatchNodes(documents: CapturedFrameDocument<FrameAxNode>[]): CaptureVomMatchNode[] {
@@ -64,6 +86,7 @@ export function projectRecordSafeObservation(input: {
  frameDocuments: CapturedFrameDocument<FrameAxNode>[];
  rendered: VomResult;
  surfaceProbes?: CapturedSurfaceProbe[];
+  hoverProbe?: HoverProbeReport;
 }): CaptureVomObservationResult {
  return {
    text: input.rendered.text,
@@ -73,5 +96,6 @@ export function projectRecordSafeObservation(input: {
    frames: projectFrames(input.frameDocuments),
    matchNodes: projectMatchNodes(input.frameDocuments),
    surfaceProbes: input.surfaceProbes,
+    ...(input.hoverProbe ? { hoverProbe: input.hoverProbe } : {}),
  };
 }
@@ -0,0 +1,154 @@
+import type { Viewport } from "@browser-skill/vom";
+import type { FrameDocument } from "../frame-document";
+import {
+  frameAxKey,
+  frameBackendKey,
+  type SemanticAxNode,
+  type SemanticFrame,
+  type SemanticGraph,
+  type SemanticGraphNode,
+  type SemanticNodeId,
+} from "./types";
+
+export interface BuildSemanticGraphInput {
+  documents: FrameDocument<SemanticAxNode>[];
+  viewport: Viewport;
+  rootFrameId?: string;
+  excludedBackendNodeIds?: ReadonlySet<number>;
+}
+
+function domNodeId(frameId: string, backendNodeId: number): SemanticNodeId {
+  return JSON.stringify([frameId, "dom", backendNodeId]);
+}
+
+function axNodeId(frameId: string, nodeId: string): SemanticNodeId {
+  return JSON.stringify([frameId, "ax", nodeId]);
+}
+
+export function buildSemanticGraph(input: BuildSemanticGraphInput): SemanticGraph {
+  const rootFrameId =
+    input.rootFrameId ??
+    input.documents.find((document) => !document.parentFrameId)?.frameId ??
+    input.documents[0]?.frameId ??
+    "root";
+  const frames = new Map<string, SemanticFrame>();
+  const nodes = new Map<SemanticNodeId, SemanticGraphNode>();
+  const nodeIdsByFrame = new Map<string, SemanticNodeId[]>();
+  const nodeByFrameBackend = new Map<string, SemanticNodeId>();
+  const nodeByFrameAx = new Map<string, SemanticNodeId>();
+
+  for (const [frameOrder, document] of input.documents.entries()) {
+    frames.set(document.frameId, {
+      frameId: document.frameId,
+      ...(document.parentFrameId ? { parentFrameId: document.parentFrameId } : {}),
+      ...(document.ownerBackendNodeId !== undefined
+        ? { ownerBackendNodeId: document.ownerBackendNodeId }
+        : {}),
+      contextScopeId: document.contextScopeId,
+      target: document.target,
+      ...(document.url ? { url: document.url } : {}),
+      order: frameOrder,
+    });
+
+    const frameNodeIds: SemanticNodeId[] = [];
+    nodeIdsByFrame.set(document.frameId, frameNodeIds);
+    for (const [index, dom] of document.domNodes.entries()) {
+      const id = domNodeId(document.frameId, dom.backendNodeId);
+      const node: SemanticGraphNode = {
+        id,
+        frameId: document.frameId,
+        backendNodeId: dom.backendNodeId,
+        dom,
+        sourceOrder: index,
+        excluded:
+          document.frameId === rootFrameId &&
+          input.excludedBackendNodeIds?.has(dom.backendNodeId) === true,
+      };
+      nodes.set(id, node);
+      frameNodeIds.push(id);
+      nodeByFrameBackend.set(frameBackendKey(document.frameId, dom.backendNodeId), id);
+    }
+
+    for (const [index, ax] of document.axNodes.entries()) {
+      const joinedId =
+        typeof ax.backendDOMNodeId === "number"
+          ? nodeByFrameBackend.get(frameBackendKey(document.frameId, ax.backendDOMNodeId))
+          : undefined;
+      const id = joinedId ?? axNodeId(document.frameId, ax.nodeId);
+      const existing = nodes.get(id);
+      if (existing) {
+        existing.ax = ax;
+        existing.axNodeId = ax.nodeId;
+      } else {
+        nodes.set(id, {
+          id,
+          frameId: document.frameId,
+          ...(typeof ax.backendDOMNodeId === "number"
+            ? { backendNodeId: ax.backendDOMNodeId }
+            : {}),
+          axNodeId: ax.nodeId,
+          ax,
+          sourceOrder: document.domNodes.length + index,
+          excluded:
+            document.frameId === rootFrameId &&
+            typeof ax.backendDOMNodeId === "number" &&
+            input.excludedBackendNodeIds?.has(ax.backendDOMNodeId) === true,
+        });
+        frameNodeIds.push(id);
+      }
+      nodeByFrameAx.set(frameAxKey(document.frameId, ax.nodeId), id);
+    }
+  }
+
+  for (const document of input.documents) {
+    for (const dom of document.domNodes) {
+      const id = nodeByFrameBackend.get(frameBackendKey(document.frameId, dom.backendNodeId));
+      const node = id ? nodes.get(id) : undefined;
+      if (!node || dom.parentBackendNodeId === null) continue;
+      node.domParentId = nodeByFrameBackend.get(
+        frameBackendKey(document.frameId, dom.parentBackendNodeId),
+      );
+    }
+    for (const ax of document.axNodes) {
+      const id = nodeByFrameAx.get(frameAxKey(document.frameId, ax.nodeId));
+      const node = id ? nodes.get(id) : undefined;
+      if (!node || !ax.parentId) continue;
+      node.axParentId = nodeByFrameAx.get(frameAxKey(document.frameId, ax.parentId));
+    }
+  }
+
+  const axChildren = new Map<SemanticNodeId, SemanticNodeId[]>();
+  const excludedQueue: SemanticNodeId[] = [];
+  for (const node of nodes.values()) {
+    if (node.axParentId) {
+      const children = axChildren.get(node.axParentId) ?? [];
+      children.push(node.id);
+      axChildren.set(node.axParentId, children);
+    }
+    if (node.excluded) excludedQueue.push(node.id);
+  }
+  for (let index = 0; index < excludedQueue.length; index += 1) {
+    for (const childId of axChildren.get(excludedQueue[index]) ?? []) {
+      const child = nodes.get(childId);
+      if (!child || child.excluded) continue;
+      child.excluded = true;
+      excludedQueue.push(childId);
+    }
+  }
+
+  for (const frame of frames.values()) {
+    if (!frame.parentFrameId || frame.ownerBackendNodeId === undefined) continue;
+    frame.ownerNodeId = nodeByFrameBackend.get(
+      frameBackendKey(frame.parentFrameId, frame.ownerBackendNodeId),
+    );
+  }
+
+  return {
+    viewport: input.viewport,
+    rootFrameId,
+    frames,
+    nodes,
+    nodeIdsByFrame,
+    nodeByFrameBackend,
+  };
+}
@@ -0,0 +1,59 @@
+import type { Viewport, VomScene } from "@browser-skill/vom";
+import type { FrameDocument } from "../frame-document";
+import { buildSemanticGraph as buildGraph } from "./build";
+import { projectSemanticGraph as projectGraph } from "./project";
+import { resolveSemanticGraph as resolveGraph } from "./resolve";
+import { normalizeSemanticStructure as normalizeStructure } from "./structure";
+import type {
+  ResolvedSemanticGraph,
+  SemanticAxNode,
+  SemanticGraph,
+  StructuredSemanticGraph,
+} from "./types";
+
+export type { SemanticAxNode } from "./types";
+
+export interface SemanticVomInput {
+  documents: FrameDocument<SemanticAxNode>[];
+  viewport: Viewport;
+  rootFrameId?: string;
+  excludedBackendNodeIds?: ReadonlySet<number>;
+}
+
+export function buildSemanticGraph(input: SemanticVomInput): SemanticGraph {
+  return buildGraph(input);
+}
+
+export function resolveSemanticGraph(
+  graph: SemanticGraph,
+  options: {
+    supplementalNames?: ReadonlyMap<string, string>;
+    identifierFallback?: boolean;
+  } = {},
+): ResolvedSemanticGraph {
+  return resolveGraph(graph, options);
+}
+
+export function normalizeSemanticStructure(graph: ResolvedSemanticGraph): StructuredSemanticGraph {
+  return normalizeStructure(graph);
+}
+
+export function projectSemanticGraph(graph: StructuredSemanticGraph): VomScene {
+  return projectGraph(graph);
+}
+
+export function buildSemanticVomScene(
+  input: SemanticVomInput & {
+    supplementalNames?: ReadonlyMap<string, string>;
+    identifierFallback?: boolean;
+  },
+): VomScene {
+  return projectSemanticGraph(
+    normalizeSemanticStructure(
+      resolveSemanticGraph(buildSemanticGraph(input), {
+        supplementalNames: input.supplementalNames,
+        identifierFallback: input.identifierFallback,
+      }),
+    ),
+  );
+}
@@ -0,0 +1,34 @@
+const IDENTIFIER_ATTRS = ["data-testid", "data-test-id", "id"] as const;
+const GENERIC_TOKENS = new Set(["btn", "button", "control", "icon", "item", "test", "tool"]);
+const GENERATED_PREFIXES = new Set(["ember", "headlessui", "mui", "radix", "react", "rc"]);
+
+function identifierTokens(value: string): string[] {
+  return value
+    .replace(/([a-z0-9])([A-Z])/g, "$1 $2")
+    .split(/[^a-zA-Z0-9]+/)
+    .map((token) => token.toLowerCase())
+    .filter(Boolean);
+}
+
+function readableIdentifier(value: string | undefined): string | undefined {
+  const raw = value?.trim();
+  if (!raw || raw.length < 3 || raw.length > 80) return undefined;
+  if (/^[a-f0-9]{8,}$/i.test(raw)) return undefined;
+
+  const tokens = identifierTokens(raw);
+  if (GENERATED_PREFIXES.has(tokens[0])) return undefined;
+  while (tokens.length > 1 && GENERIC_TOKENS.has(tokens[0])) tokens.shift();
+  while (tokens.length > 1 && GENERIC_TOKENS.has(tokens[tokens.length - 1])) tokens.pop();
+  if (tokens.length === 0 || !tokens.some((token) => /[a-z]{3,}/.test(token))) return undefined;
+  return tokens
+    .map((token, index) => (index === 0 ? `${token[0].toUpperCase()}${token.slice(1)}` : token))
+    .join(" ");
+}
+
+export function stableIdentifierName(attrs: Readonly<Record<string, string>>): string | undefined {
+  for (const name of IDENTIFIER_ATTRS) {
+    const label = readableIdentifier(attrs[name]);
+    if (label) return label;
+  }
+  return undefined;
+}
@@ -0,0 +1,85 @@
+import type { VomNode, VomScene } from "@browser-skill/vom";
+import type { SemanticNodeId, StructuredSemanticGraph, StructuredSemanticNode } from "./types";
+
+function retained(node: StructuredSemanticNode): boolean {
+  return node.structure.kind === "keep" || node.structure.kind === "inferred-group";
+}
+
+function connectedFrameIds(graph: StructuredSemanticGraph): Set<string> {
+  const connected = new Set<string>([graph.rootFrameId]);
+  const childrenByParent = new Map<string, string[]>();
+  for (const frame of graph.frames.values()) {
+    if (!frame.parentFrameId) continue;
+    const children = childrenByParent.get(frame.parentFrameId) ?? [];
+    children.push(frame.frameId);
+    childrenByParent.set(frame.parentFrameId, children);
+  }
+  const queue = [graph.rootFrameId];
+  for (let index = 0; index < queue.length; index += 1) {
+    for (const frameId of childrenByParent.get(queue[index]) ?? []) {
+      if (connected.has(frameId)) continue;
+      const frame = graph.frames.get(frameId);
+      if (!frame?.ownerNodeId) continue;
+      const owner = graph.nodes.get(frame.ownerNodeId);
+      if (!owner || !retained(owner)) continue;
+      connected.add(frame.frameId);
+      queue.push(frame.frameId);
+    }
+  }
+  return connected;
+}
+
+function domAncestors(
+  graph: StructuredSemanticGraph,
+  node: StructuredSemanticNode,
+  numericId: ReadonlyMap<SemanticNodeId, number>,
+): number[] {
+  const ancestors: number[] = [];
+  const seen = new Set<SemanticNodeId>();
+  let current = node.domParentId;
+  while (current && !seen.has(current)) {
+    seen.add(current);
+    const id = numericId.get(current);
+    if (id !== undefined) ancestors.push(id);
+    current = graph.nodes.get(current)?.domParentId;
+  }
+  return ancestors;
+}
+
+export function projectSemanticGraph(graph: StructuredSemanticGraph): VomScene {
+  const connectedFrames = connectedFrameIds(graph);
+  const orderedNodes = [...graph.frames.values()]
+    .filter((frame) => connectedFrames.has(frame.frameId))
+    .sort((a, b) => a.order - b.order)
+    .flatMap((frame) =>
+      (graph.nodeIdsByFrame.get(frame.frameId) ?? [])
+        .map((id) => graph.nodes.get(id))
+        .filter((node): node is StructuredSemanticNode => node !== undefined && retained(node))
+        .sort((a, b) => a.sourceOrder - b.sourceOrder),
+    );
+
+  const numericId = new Map<SemanticNodeId, number>();
+  orderedNodes.forEach((node, index) => numericId.set(node.id, index + 1));
+  const nodes: VomNode[] = orderedNodes.map((node) => ({
+    ...node.vom,
+    id: numericId.get(node.id) as number,
+    parentId: node.semanticParentId ? (numericId.get(node.semanticParentId) ?? null) : null,
+    ...(node.backendNodeId !== undefined ? { backendNodeId: node.backendNodeId } : {}),
+    frameId: node.frameId,
+    contextScopeId: graph.frames.get(node.frameId)?.contextScopeId ?? node.frameId,
+    referenceable: node.referenceable,
+    ...(node.dom
+      ? {
+          domParentId:
+            node.domParentId === undefined ? null : (numericId.get(node.domParentId) ?? null),
+          domAncestorIds: domAncestors(graph, node, numericId),
+        }
+      : {}),
+  }));
+
+  return {
+    viewport: graph.viewport,
+    nodes,
+    rootFrameId: graph.rootFrameId,
+  };
+}
@@ -0,0 +1,521 @@
+import type { VomNode } from "@browser-skill/vom";
+import { stableIdentifierName } from "./name-evidence";
+import type {
+  ResolvedSemanticGraph,
+  ResolvedSemanticNode,
+  SemanticAxNode,
+  SemanticGraph,
+  SemanticGraphNode,
+  SemanticNodeId,
+} from "./types";
+import { frameBackendKey } from "./types";
+
+const FORM_TAGS = new Set(["input", "textarea", "select"]);
+const NATIVE_CONTROL_TAGS = new Set(["button", "input", "select", "textarea"]);
+const TEXT_AX_ROLES = new Set(["statictext", "inlinetextbox", "labeltext", "text"]);
+const INTERACTIVE_ROLES = new Set([
+  "button",
+  "checkbox",
+  "combobox",
+  "link",
+  "listbox",
+  "menuitem",
+  "menuitemcheckbox",
+  "menuitemradio",
+  "option",
+  "radio",
+  "searchbox",
+  "slider",
+  "spinbutton",
+  "switch",
+  "tab",
+  "textbox",
+  "treeitem",
+]);
+const SENSITIVE_INPUT_TYPES = new Set([
+  "password",
+  "credit-card",
+  "one-time-code",
+  "current-password",
+  "new-password",
+]);
+
+function clean(value: string | undefined): string | undefined {
+  const normalized = value?.replace(/\s+/g, " ").trim();
+  return normalized || undefined;
+}
+
+function axValue(field?: { value?: string | number | boolean }): string | undefined {
+  return field?.value === undefined ? undefined : clean(String(field.value));
+}
+
+function axProperty(node: SemanticAxNode | undefined, name: string): string | undefined {
+  return axValue(node?.properties?.find((property) => property.name === name)?.value);
+}
+
+function normalizeRole(value: string | undefined): string | undefined {
+  const role = clean(value)?.toLowerCase();
+  return role || undefined;
+}
+
+function nativeRole(tag: string, attrs: Record<string, string>): string | undefined {
+  if (tag === "button") return "button";
+  if (tag === "textarea") return "textbox";
+  if (tag === "select") return attrs.multiple === undefined ? "combobox" : "listbox";
+  if (tag === "a" && attrs.href) return "link";
+  if (tag === "iframe") return "Iframe";
+  if (tag === "dialog") return "dialog";
+  if (tag === "img") return "img";
+  if (tag === "table") return "table";
+  if (tag === "tr") return "row";
+  if (tag === "th") return "columnheader";
+  if (tag === "td") return "cell";
+  if (tag === "ul" || tag === "ol") return "list";
+  if (tag === "li") return "listitem";
+  if (/^h[1-6]$/.test(tag)) return "heading";
+  if (tag === "nav") return "navigation";
+  if (tag === "main") return "main";
+  if (tag === "form") return "form";
+  if (tag === "input") {
+    const type = (attrs.type ?? "text").toLowerCase();
+    if (type === "hidden") return undefined;
+    if (type === "checkbox") return "checkbox";
+    if (type === "radio") return "radio";
+    if (type === "range") return "slider";
+    if (type === "number") return "spinbutton";
+    if (type === "search") return "searchbox";
+    if (["button", "submit", "reset", "image"].includes(type)) return "button";
+    return "textbox";
+  }
+  return undefined;
+}
+
+function domRole(tag: string, attrs: Record<string, string>): string | undefined {
+  return normalizeRole(attrs.role) ?? nativeRole(tag, attrs);
+}
+
+function resolvedRole(node: SemanticGraphNode): {
+  value?: string;
+  source: ResolvedSemanticNode["roleSource"];
+} {
+  const rawAxRole = clean(axValue(node.ax?.role));
+  const axRole = normalizeRole(rawAxRole);
+  const attrs = node.dom?.attrs ?? {};
+  const explicitDomRole = normalizeRole(attrs.role);
+  const nativeDomRole = nativeRole(node.dom?.tag.toLowerCase() ?? "", attrs);
+  const usableAxRole = node.ax?.ignored !== true;
+  if (usableAxRole && axRole && !["generic", "none", "presentation"].includes(axRole)) {
+    return { value: rawAxRole, source: "ax" };
+  }
+  if (explicitDomRole) return { value: explicitDomRole, source: "dom-explicit" };
+  if (nativeDomRole) return { value: nativeDomRole, source: "dom-native" };
+  if (rawAxRole) {
+    return { value: rawAxRole, source: usableAxRole ? "ax" : "ax-ignored" };
+  }
+  return { source: "none" };
+}
+
+function sensitive(node: SemanticGraphNode): boolean {
+  const attrs = node.dom?.attrs ?? {};
+  const type = (attrs.type ?? "").toLowerCase();
+  const autocomplete = (attrs.autocomplete ?? "").toLowerCase();
+  return (
+    type === "password" ||
+    autocomplete.startsWith("cc-") ||
+    SENSITIVE_INPUT_TYPES.has(autocomplete) ||
+    SENSITIVE_INPUT_TYPES.has(axProperty(node.ax, "inputType") ?? "")
+  );
+}
+
+function inputState(
+  node: SemanticGraphNode,
+  role: string | undefined,
+  value: string | undefined,
+  isSensitive: boolean,
+): VomNode["inputState"] {
+  if (node.dom?.formState) return node.dom.formState;
+  const tag = node.dom?.tag.toLowerCase() ?? "";
+  if (!FORM_TAGS.has(tag) && !["textbox", "searchbox"].includes(role ?? "")) return undefined;
+  if (isSensitive) return value ? "filled" : "empty";
+  if (node.dom?.formValue !== undefined) {
+    if (node.dom.formValue === "") return "empty";
+    return node.dom.formValue === (node.dom.formDefaultValue ?? "") ? "default" : "filled";
+  }
+  return value ? "filled" : "empty";
+}
+
+function externalHrefHost(
+  href: string | undefined,
+  pageUrl: string | undefined,
+): string | undefined {
+  if (!href || !pageUrl) return undefined;
+  try {
+    const page = new URL(pageUrl);
+    const target = new URL(href, page);
+    return target.origin === page.origin ? undefined : target.hostname;
+  } catch {
+    return undefined;
+  }
+}
+
+interface ResolveIndexes {
+  domChildren: Map<SemanticNodeId, SemanticNodeId[]>;
+  axChildren: Map<SemanticNodeId, SemanticNodeId[]>;
+  domIdIndex: Map<string, SemanticNodeId>;
+  labelForIndex: Map<string, SemanticNodeId[]>;
+  domText: (nodeId: SemanticNodeId) => string | undefined;
+  axText: (nodeId: SemanticNodeId) => string | undefined;
+  hasNativeDescendant: (nodeId: SemanticNodeId) => boolean;
+}
+
+function buildIndexes(graph: SemanticGraph): ResolveIndexes {
+  const domChildren = new Map<SemanticNodeId, SemanticNodeId[]>();
+  const axChildren = new Map<SemanticNodeId, SemanticNodeId[]>();
+  const domIdIndex = new Map<string, SemanticNodeId>();
+  const labelForIndex = new Map<string, SemanticNodeId[]>();
+  for (const node of graph.nodes.values()) {
+    if (node.domParentId) {
+      const children = domChildren.get(node.domParentId) ?? [];
+      children.push(node.id);
+      domChildren.set(node.domParentId, children);
+    }
+    if (node.axParentId) {
+      const children = axChildren.get(node.axParentId) ?? [];
+      children.push(node.id);
+      axChildren.set(node.axParentId, children);
+    }
+    const id = clean(node.dom?.attrs.id);
+    if (id) domIdIndex.set(`${node.frameId}\u0000${id}`, node.id);
+    const targetId = clean(node.dom?.attrs.for);
+    if (node.dom?.tag.toLowerCase() === "label" && targetId) {
+      const key = `${node.frameId}\u0000${targetId}`;
+      const labels = labelForIndex.get(key) ?? [];
+      labels.push(node.id);
+      labelForIndex.set(key, labels);
+    }
+  }
+
+  for (const [parentId, children] of axChildren) {
+    const order = graph.nodes.get(parentId)?.ax?.childIds ?? [];
+    const orderByAxId = new Map(order.map((nodeId, index) => [nodeId, index]));
+    children.sort((a, b) => {
+      const aIndex = orderByAxId.get(graph.nodes.get(a)?.axNodeId ?? "") ?? -1;
+      const bIndex = orderByAxId.get(graph.nodes.get(b)?.axNodeId ?? "") ?? -1;
+      return (
+        (aIndex < 0 ? Number.MAX_SAFE_INTEGER : aIndex) -
+        (bIndex < 0 ? Number.MAX_SAFE_INTEGER : bIndex)
+      );
+    });
+  }
+
+  const textMemo = new Map<SemanticNodeId, string | undefined>();
+  const resolvingText = new Set<SemanticNodeId>();
+  const domText = (nodeId: SemanticNodeId): string | undefined => {
+    if (textMemo.has(nodeId)) return textMemo.get(nodeId);
+    if (resolvingText.has(nodeId)) return undefined;
+    resolvingText.add(nodeId);
+    const node = graph.nodes.get(nodeId);
+    const parts: string[] = [];
+    const own = clean(node?.dom?.textContent);
+    if (own) parts.push(own);
+    for (const childId of domChildren.get(nodeId) ?? []) {
+      const child = graph.nodes.get(childId);
+      const childRole = child
+        ? domRole(child.dom?.tag.toLowerCase() ?? "", child.dom?.attrs ?? {})
+        : undefined;
+      if (childRole && INTERACTIVE_ROLES.has(childRole.toLowerCase())) continue;
+      const childText = domText(childId);
+      if (childText) parts.push(childText);
+      if (parts.join(" ").length >= 240) break;
+    }
+    resolvingText.delete(nodeId);
+    const result = clean(parts.join(" ").slice(0, 240));
+    textMemo.set(nodeId, result);
+    return result;
+  };
+
+  const axTextMemo = new Map<SemanticNodeId, string | undefined>();
+  const resolvingAxText = new Set<SemanticNodeId>();
+  const axText = (nodeId: SemanticNodeId): string | undefined => {
+    if (axTextMemo.has(nodeId)) return axTextMemo.get(nodeId);
+    if (resolvingAxText.has(nodeId)) return undefined;
+    resolvingAxText.add(nodeId);
+    const complete = (value: string | undefined): string | undefined => {
+      resolvingAxText.delete(nodeId);
+      axTextMemo.set(nodeId, value);
+      return value;
+    };
+    const node = graph.nodes.get(nodeId);
+    const role = normalizeRole(axValue(node?.ax?.role)) ?? "";
+    if (TEXT_AX_ROLES.has(role)) {
+      const own = clean(axValue(node?.ax?.name) ?? axValue(node?.ax?.value));
+      if (own) return complete(own);
+    }
+    const parts: string[] = [];
+    for (const childId of axChildren.get(nodeId) ?? []) {
+      const child = graph.nodes.get(childId);
+      const childRole = normalizeRole(axValue(child?.ax?.role)) ?? "";
+      if (INTERACTIVE_ROLES.has(childRole)) continue;
+      const childText = axText(childId);
+      if (childText) parts.push(childText);
+      if (parts.join(" ").length >= 240) break;
+    }
+    return complete(clean(parts.join(" ").slice(0, 240)));
+  };
+
+  const nativeMemo = new Map<SemanticNodeId, boolean>();
+  const hasNativeDescendant = (nodeId: SemanticNodeId): boolean => {
+    const cached = nativeMemo.get(nodeId);
+    if (cached !== undefined) return cached;
+    nativeMemo.set(nodeId, false);
+    for (const childId of domChildren.get(nodeId) ?? []) {
+      const child = graph.nodes.get(childId);
+      const childRole =
+        (child?.ax?.ignored === true ? undefined : normalizeRole(axValue(child?.ax?.role))) ??
+        (child ? domRole(child.dom?.tag.toLowerCase() ?? "", child.dom?.attrs ?? {}) : undefined);
+      if (
+        (child?.dom && NATIVE_CONTROL_TAGS.has(child.dom.tag.toLowerCase())) ||
+        INTERACTIVE_ROLES.has(childRole ?? "") ||
+        hasNativeDescendant(childId)
+      ) {
+        nativeMemo.set(nodeId, true);
+        return true;
+      }
+    }
+    return false;
+  };
+
+  return {
+    domChildren,
+    axChildren,
+    domIdIndex,
+    labelForIndex,
+    domText,
+    axText,
+    hasNativeDescendant,
+  };
+}
+
+function ariaLabelledText(node: SemanticGraphNode, indexes: ResolveIndexes): string | undefined {
+  const ids = (node.dom?.attrs["aria-labelledby"] ?? "").split(/\s+/).filter(Boolean);
+  const parts = ids.flatMap((id) => {
+    const target = indexes.domIdIndex.get(`${node.frameId}\u0000${id}`);
+    return target ? (indexes.domText(target) ?? []) : [];
+  });
+  return clean(parts.join(" "));
+}
+
+function nativeLabelText(
+  node: SemanticGraphNode,
+  graph: SemanticGraph,
+  indexes: ResolveIndexes,
+): string | undefined {
+  const id = clean(node.dom?.attrs.id);
+  if (id) {
+    const labels = indexes.labelForIndex.get(`${node.frameId}\u0000${id}`) ?? [];
+    const explicit = clean(
+      labels
+        .map((labelId) => indexes.domText(labelId))
+        .filter(Boolean)
+        .join(" "),
+    );
+    if (explicit) return explicit;
+  }
+  let parentId = node.domParentId;
+  let guard = 0;
+  while (parentId && guard <= graph.nodes.size) {
+    const parent = graph.nodes.get(parentId);
+    if (!parent) break;
+    if (parent.dom?.tag.toLowerCase() === "label") return indexes.domText(parentId);
+    parentId = parent.domParentId;
+    guard += 1;
+  }
+  return undefined;
+}
+
+function precedingAxText(
+  node: SemanticGraphNode,
+  graph: SemanticGraph,
+  indexes: ResolveIndexes,
+): string | undefined {
+  if (!node.axParentId) return undefined;
+  const siblings = indexes.axChildren.get(node.axParentId) ?? [];
+  const index = siblings.indexOf(node.id);
+  for (let offset = 1; offset <= 4 && index - offset >= 0; offset += 1) {
+    const sibling = graph.nodes.get(siblings[index - offset]);
+    const role = normalizeRole(axValue(sibling?.ax?.role)) ?? "";
+    if (INTERACTIVE_ROLES.has(role)) break;
+    if (!TEXT_AX_ROLES.has(role) && role !== "generic") continue;
+    const text = clean(axValue(sibling?.ax?.name) ?? axValue(sibling?.ax?.value))?.replace(
+      /[：:]\s*$/,
+      "",
+    );
+    if (text && text.length <= 80) return text;
+  }
+  return undefined;
+}
+
+function precedingDomText(
+  node: SemanticGraphNode,
+  graph: SemanticGraph,
+  indexes: ResolveIndexes,
+): string | undefined {
+  if (!node.domParentId) return undefined;
+  const siblings = indexes.domChildren.get(node.domParentId) ?? [];
+  const index = siblings.indexOf(node.id);
+  for (let offset = 1; offset <= 4 && index - offset >= 0; offset += 1) {
+    const sibling = graph.nodes.get(siblings[index - offset]);
+    const siblingRole = sibling
+      ? domRole(sibling.dom?.tag.toLowerCase() ?? "", sibling.dom?.attrs ?? {})
+      : undefined;
+    if (siblingRole && INTERACTIVE_ROLES.has(siblingRole.toLowerCase())) break;
+    const text = indexes.domText(siblings[index - offset])?.replace(/[：:]\s*$/, "");
+    if (text && text.length <= 80) return text;
+  }
+  return undefined;
+}
+
+function resolvedName(
+  node: SemanticGraphNode,
+  role: string | undefined,
+  graph: SemanticGraph,
+  indexes: ResolveIndexes,
+  supplementalNames: ReadonlyMap<string, string>,
+  identifierFallback: boolean,
+): string | undefined {
+  const attrs = node.dom?.attrs ?? {};
+  const formControl = FORM_TAGS.has(node.dom?.tag.toLowerCase() ?? "");
+  const descendantText = indexes.domText(node.id);
+  const interactive =
+    INTERACTIVE_ROLES.has(role?.toLowerCase() ?? "") ||
+    NATIVE_CONTROL_TAGS.has(node.dom?.tag.toLowerCase() ?? "");
+  const candidates = [
+    node.ax?.ignored === true ? undefined : axValue(node.ax?.name),
+    ariaLabelledText(node, indexes),
+    clean(attrs["aria-label"]),
+    nativeLabelText(node, graph, indexes),
+    clean(attrs.title),
+    clean(attrs.alt),
+    node.ax?.ignored === true ? undefined : indexes.axText(node.id),
+    descendantText,
+    formControl ? precedingAxText(node, graph, indexes) : undefined,
+    formControl ? precedingDomText(node, graph, indexes) : undefined,
+    formControl ? clean(node.dom?.formPlaceholder ?? attrs.placeholder) : undefined,
+    formControl || !interactive || node.backendNodeId === undefined
+      ? undefined
+      : clean(supplementalNames.get(frameBackendKey(node.frameId, node.backendNodeId))),
+    identifierFallback && interactive ? stableIdentifierName(attrs) : undefined,
+  ];
+  let name = candidates.find((candidate) => candidate !== undefined);
+  const hasPopup = axProperty(node.ax, "hasPopup");
+  if (name && hasPopup && hasPopup !== "false") {
+    name =
+      axProperty(node.ax, "expanded") === "true" ? `${name} [expanded]` : `${name} [has-submenu]`;
+  }
+  if (!name && role?.toLowerCase() === "iframe") return clean(attrs.id);
+  return name;
+}
+
+function insideNative(node: SemanticGraphNode, graph: SemanticGraph): boolean {
+  let parentId = node.domParentId;
+  let guard = 0;
+  while (parentId && guard <= graph.nodes.size) {
+    const parent = graph.nodes.get(parentId);
+    if (!parent) break;
+    if (parent.dom && NATIVE_CONTROL_TAGS.has(parent.dom.tag.toLowerCase())) return true;
+    parentId = parent.domParentId;
+    guard += 1;
+  }
+  return false;
+}
+
+function nearbyText(
+  node: SemanticGraphNode,
+  graph: SemanticGraph,
+  indexes: ResolveIndexes,
+): string | undefined {
+  if (!node.domParentId) return undefined;
+  const siblings = indexes.domChildren.get(node.domParentId) ?? [];
+  const index = siblings.indexOf(node.id);
+  if (index < 0) return undefined;
+  const texts = siblings
+    .slice(Math.max(0, index - 3), index + 4)
+    .filter((id) => id !== node.id)
+    .flatMap((id) => indexes.domText(id) ?? [])
+    .slice(0, 3);
+  return clean(texts.join(" "));
+}
+
+export function resolveSemanticGraph(
+  graph: SemanticGraph,
+  options: {
+    supplementalNames?: ReadonlyMap<string, string>;
+    identifierFallback?: boolean;
+  } = {},
+): ResolvedSemanticGraph {
+  const indexes = buildIndexes(graph);
+  const supplementalNames = options.supplementalNames ?? new Map<string, string>();
+  const identifierFallback = options.identifierFallback ?? true;
+  const nodes = new Map<SemanticNodeId, ResolvedSemanticNode>();
+  for (const node of graph.nodes.values()) {
+    const roleResolution = resolvedRole(node);
+    const role = roleResolution.value;
+    const name = resolvedName(node, role, graph, indexes, supplementalNames, identifierFallback);
+    const isSensitive = sensitive(node);
+    const sourceValue = node.dom?.formValue ?? axValue(node.ax?.value);
+    const value = isSensitive ? undefined : sourceValue;
+    const attrs = { ...(node.dom?.attrs ?? {}) };
+    if (isSensitive) delete attrs.value;
+    const frame = graph.frames.get(node.frameId);
+    const tag = node.dom?.tag.toLowerCase() ?? "";
+    const vom: ResolvedSemanticNode["vom"] = {
+      tag,
+      rect: node.dom?.rect ?? null,
+      paintOrder: node.dom?.paintOrder ?? 0,
+      position: node.dom?.position || "static",
+      pointerEvents: node.dom?.pointerEvents || "auto",
+      ...(node.dom?.cursor ? { cursor: node.dom.cursor } : {}),
+      ...(role ? { role } : {}),
+      ...(name ? { name } : {}),
+      ...(value !== undefined ? { value } : {}),
+      ...(clean(node.dom?.formPlaceholder ?? attrs.placeholder)
+        ? { placeholder: clean(node.dom?.formPlaceholder ?? attrs.placeholder) }
+        : {}),
+      attrs,
+      ...(clean(node.dom?.textContent) ? { text: clean(node.dom?.textContent) } : {}),
+      ...(nearbyText(node, graph, indexes) ? { nearbyText: nearbyText(node, graph, indexes) } : {}),
+      inputState: inputState(node, role, sourceValue, isSensitive),
+      sensitive: isSensitive,
+      modal:
+        ["dialog", "alertdialog"].includes(role?.toLowerCase() ?? "") ||
+        tag === "dialog" ||
+        (attrs["aria-modal"] ?? "").toLowerCase() === "true",
+      disabled:
+        Object.prototype.hasOwnProperty.call(attrs, "disabled") ||
+        (attrs["aria-disabled"] ?? "").toLowerCase() === "true",
+      inert: Object.prototype.hasOwnProperty.call(attrs, "inert"),
+      hasNativeDescendant: indexes.hasNativeDescendant(node.id),
+      insideNative: insideNative(node, graph),
+      ...(role?.toLowerCase() === "link" ? { href: externalHrefHost(attrs.href, frame?.url) } : {}),
+    };
+    const selected = node.ax?.ignored === true ? undefined : axProperty(node.ax, "selected");
+    const expanded = node.ax?.ignored === true ? undefined : axProperty(node.ax, "expanded");
+    const controls = node.ax?.ignored === true ? undefined : axProperty(node.ax, "controls");
+    if (selected === "true" && !vom.attrs?.["aria-selected"]) {
+      vom.attrs = { ...(vom.attrs ?? {}), "aria-selected": "true" };
+    }
+    if (expanded === "true" && !vom.attrs?.["aria-expanded"]) {
+      vom.attrs = { ...(vom.attrs ?? {}), "aria-expanded": "true" };
+    }
+    if (controls && !vom.attrs?.["aria-controls"]) {
+      vom.attrs = { ...(vom.attrs ?? {}), "aria-controls": controls };
+    }
+    nodes.set(node.id, {
+      ...node,
+      vom,
+      referenceable: node.backendNodeId !== undefined,
+      roleSource: roleResolution.source,
+    });
+  }
+  return { ...graph, nodes };
+}
@@ -0,0 +1,456 @@
+import {
+  applyVomInteractionRecovery,
+  isVomReferenceNode,
+  isVomStructuralRole,
+  type VomNode,
+} from "@browser-skill/vom";
+import type {
+  ResolvedSemanticGraph,
+  ResolvedSemanticNode,
+  SemanticNodeId,
+  StructureDecision,
+  StructuredSemanticGraph,
+  StructuredSemanticNode,
+} from "./types";
+
+const TRANSPARENT_ROLES = new Set(["", "generic", "none", "presentation", "inlinetextbox"]);
+const ROOT_ROLES = new Set(["rootwebarea", "webarea"]);
+const CONTENT_BOUNDARY_ROLES = new Set([
+  "article",
+  "dialog",
+  "document",
+  "feed",
+  "form",
+  "grid",
+  "heading",
+  "iframe",
+  "list",
+  "main",
+  "navigation",
+  "paragraph",
+  "region",
+  "section",
+  "table",
+  "tree",
+]);
+
+function hasMeaningfulRelations(node: ResolvedSemanticNode): boolean {
+  const attrs = node.vom.attrs ?? {};
+  return ["aria-controls", "aria-labelledby", "aria-owns", "aria-describedby"].some((name) =>
+    attrs[name]?.trim(),
+  );
+}
+
+function explicitStructural(node: ResolvedSemanticNode): boolean {
+  return (
+    isVomStructuralRole(node.vom.role) &&
+    node.roleSource !== "none" &&
+    node.roleSource !== "ax-ignored"
+  );
+}
+
+function hasUsableAxSemantics(node: ResolvedSemanticNode): boolean {
+  return node.ax !== undefined && node.ax.ignored !== true;
+}
+
+function isRenderedDomFallback(node: ResolvedSemanticNode): boolean {
+  if (!node.dom) return false;
+  const attrs = node.dom.attrs;
+  if (
+    Object.prototype.hasOwnProperty.call(attrs, "hidden") ||
+    Object.prototype.hasOwnProperty.call(attrs, "inert") ||
+    (attrs["aria-hidden"] ?? "").toLowerCase() === "true"
+  ) {
+    return false;
+  }
+  return node.dom.rendered ?? (node.dom.localRect != null || node.dom.rect != null);
+}
+
+function initialParentId(
+  graph: ResolvedSemanticGraph,
+  node: ResolvedSemanticNode,
+): SemanticNodeId | undefined {
+  let parentId = node.axParentId ?? node.domParentId;
+  if (node.axParentId && node.domParentId && node.axParentId !== node.domParentId) {
+    const axParent = graph.nodes.get(node.axParentId);
+    const axRole = axParent?.vom.role?.toLowerCase() ?? "";
+    const meaningfulAxParent =
+      axParent !== undefined &&
+      !ROOT_ROLES.has(axRole) &&
+      (explicitStructural(axParent) ||
+        !TRANSPARENT_ROLES.has(axRole) ||
+        Boolean(axParent.vom.name || axParent.vom.text || hasMeaningfulRelations(axParent)));
+    parentId = meaningfulAxParent ? node.axParentId : node.domParentId;
+  }
+  if (parentId) return parentId;
+  if (node.frameId === graph.rootFrameId) return undefined;
+  return graph.frames.get(node.frameId)?.ownerNodeId;
+}
+
+function orderedNodes(graph: ResolvedSemanticGraph): ResolvedSemanticNode[] {
+  return [...graph.frames.values()]
+    .sort((a, b) => a.order - b.order)
+    .flatMap((frame) =>
+      (graph.nodeIdsByFrame.get(frame.frameId) ?? [])
+        .map((id) => graph.nodes.get(id))
+        .filter((node): node is ResolvedSemanticNode => node !== undefined)
+        .sort((a, b) => a.sourceOrder - b.sourceOrder),
+    );
+}
+
+function recoveredNodes(
+  graph: ResolvedSemanticGraph,
+  nodes: ResolvedSemanticNode[],
+): Map<SemanticNodeId, VomNode> {
+  const numericId = new Map(nodes.map((node, index) => [node.id, index + 1]));
+  const semanticId = new Map([...numericId].map(([id, numeric]) => [numeric, id]));
+  const provisional = nodes.map((node) => ({
+    ...node.vom,
+    id: numericId.get(node.id) as number,
+    parentId: (() => {
+      const parent = initialParentId(graph, node);
+      return parent ? (numericId.get(parent) ?? null) : null;
+    })(),
+    ...(node.backendNodeId !== undefined ? { backendNodeId: node.backendNodeId } : {}),
+    frameId: node.frameId,
+    contextScopeId: graph.frames.get(node.frameId)?.contextScopeId ?? node.frameId,
+    referenceable: node.referenceable,
+  }));
+  return new Map(
+    applyVomInteractionRecovery(provisional).flatMap((node) => {
+      const id = semanticId.get(node.id);
+      return id ? [[id, node] as const] : [];
+    }),
+  );
+}
+
+function redundantSourceNodes(
+  graph: ResolvedSemanticGraph,
+  nodes: ResolvedSemanticNode[],
+  recovered: ReadonlyMap<SemanticNodeId, VomNode>,
+): Set<SemanticNodeId> {
+  const byKey = new Map<string, ResolvedSemanticNode[]>();
+  for (const node of nodes) {
+    const output = recovered.get(node.id) as VomNode;
+    const name = output.name?.trim().toLowerCase() ?? "";
+    if (!name || !isVomReferenceNode({ ...output, referenceable: true })) continue;
+    const key = `${node.frameId}\u0000${initialParentId(graph, node) ?? ""}\u0000${output.role?.toLowerCase() ?? ""}\u0000${name}\u0000${output.sensitive === true}`;
+    const matches = byKey.get(key) ?? [];
+    matches.push(node);
+    byKey.set(key, matches);
+  }
+  const redundant = new Set<SemanticNodeId>();
+  for (const matches of byKey.values()) {
+    const axOnly = matches.filter((node) => node.ax && !node.dom);
+    const domOnly = matches.filter((node) => node.dom && !node.ax);
+    if (matches.length === 2 && axOnly.length === 1 && domOnly.length === 1) {
+      redundant.add(domOnly[0].id);
+    }
+  }
+  return redundant;
+}
+
+function baseDecision(
+  graph: ResolvedSemanticGraph,
+  node: ResolvedSemanticNode,
+  output: VomNode,
+  frameOwnerIds: ReadonlySet<SemanticNodeId>,
+  redundant: ReadonlySet<SemanticNodeId>,
+): StructureDecision {
+  if (node.excluded) return { kind: "excluded", reason: "excluded" };
+  if (redundant.has(node.id)) return { kind: "excluded", reason: "redundant-source" };
+  if (!hasUsableAxSemantics(node) && !isRenderedDomFallback(node)) {
+    return { kind: "excluded", reason: "non-rendered-dom-fallback" };
+  }
+  if (frameOwnerIds.has(node.id)) return { kind: "keep", reason: "frame-owner" };
+  if (node.frameId !== graph.rootFrameId && ROOT_ROLES.has(output.role?.toLowerCase() ?? "")) {
+    return { kind: "transparent", reason: "child-document-root" };
+  }
+  if (node.ax?.ignored === true && !node.dom) {
+    return { kind: "transparent", reason: "ax-ignored" };
+  }
+  const role = output.role?.toLowerCase() ?? "";
+  if (!TRANSPARENT_ROLES.has(role)) return { kind: "keep", reason: "semantic" };
+  if (
+    output.name ||
+    output.text ||
+    output.value ||
+    output.placeholder ||
+    hasMeaningfulRelations(node) ||
+    (output.rect && ["fixed", "sticky"].includes(output.position))
+  ) {
+    return { kind: "keep", reason: "semantic" };
+  }
+  return { kind: "transparent", reason: "wrapper" };
+}
+
+function buildChildren(
+  nodes: ResolvedSemanticNode[],
+  relation: "axParentId" | "domParentId",
+): Map<SemanticNodeId, SemanticNodeId[]> {
+  const children = new Map<SemanticNodeId, SemanticNodeId[]>();
+  for (const node of nodes) {
+    const parentId = node[relation];
+    if (!parentId) continue;
+    const siblings = children.get(parentId) ?? [];
+    siblings.push(node.id);
+    children.set(parentId, siblings);
+  }
+  return children;
+}
+
+function explicitDomAncestors(
+  graph: ResolvedSemanticGraph,
+  nodes: ResolvedSemanticNode[],
+  domChildren: ReadonlyMap<SemanticNodeId, SemanticNodeId[]>,
+): Set<SemanticNodeId> {
+  const inside = new Set<SemanticNodeId>();
+  const roots = nodes.filter((node) => !node.domParentId);
+  const queue = roots.map((node) => node.id);
+  for (let index = 0; index < queue.length; index += 1) {
+    const parentId = queue[index];
+    const parent = graph.nodes.get(parentId);
+    const parentIsBoundary =
+      parent !== undefined &&
+      explicitStructural(parent) &&
+      !ROOT_ROLES.has(parent.vom.role?.toLowerCase() ?? "");
+    for (const childId of domChildren.get(parentId) ?? []) {
+      if (inside.has(parentId) || parentIsBoundary) inside.add(childId);
+      queue.push(childId);
+    }
+  }
+  return inside;
+}
+
+function reliableGroupCandidates(
+  graph: ResolvedSemanticGraph,
+  nodes: ResolvedSemanticNode[],
+  recovered: ReadonlyMap<SemanticNodeId, VomNode>,
+  decisions: ReadonlyMap<SemanticNodeId, StructureDecision>,
+  domChildren: ReadonlyMap<SemanticNodeId, SemanticNodeId[]>,
+): Set<SemanticNodeId> {
+  const insideExplicitStructure = explicitDomAncestors(graph, nodes, domChildren);
+  const remainingChildren = new Map(
+    nodes.map((node) => [node.id, domChildren.get(node.id)?.length ?? 0]),
+  );
+  const summaries = new Map<SemanticNodeId, { blocked: boolean; interactions: number }>();
+  const queue = nodes
+    .filter((node) => (remainingChildren.get(node.id) ?? 0) === 0)
+    .map((node) => node.id);
+  for (let index = 0; index < queue.length; index += 1) {
+    const nodeId = queue[index];
+    const node = graph.nodes.get(nodeId);
+    const output = recovered.get(nodeId);
+    if (!node || !output) continue;
+    const role = output.role?.toLowerCase() ?? "";
+    const excluded = decisions.get(nodeId)?.kind === "excluded";
+    const blocked = excluded || explicitStructural(node) || CONTENT_BOUNDARY_ROLES.has(role);
+    const summary = excluded
+      ? { blocked: true, interactions: 0 }
+      : isVomReferenceNode(output)
+        ? { blocked: false, interactions: 1 }
+        : blocked
+          ? { blocked: true, interactions: 0 }
+          : (domChildren.get(nodeId) ?? []).reduce(
+              (combined, childId) => {
+                const child = summaries.get(childId);
+                return {
+                  blocked: combined.blocked || !child || child.blocked,
+                  interactions: Math.min(2, combined.interactions + (child?.interactions ?? 0)),
+                };
+              },
+              { blocked: false, interactions: 0 },
+            );
+    summaries.set(nodeId, summary);
+    const parentId = node.domParentId;
+    if (!parentId) continue;
+    const remaining = (remainingChildren.get(parentId) ?? 1) - 1;
+    remainingChildren.set(parentId, remaining);
+    if (remaining === 0) queue.push(parentId);
+  }
+
+  const candidates = new Set<SemanticNodeId>();
+  for (const node of nodes) {
+    const output = recovered.get(node.id) as VomNode;
+    const role = output.role?.toLowerCase() ?? "";
+    if (
+      !node.dom ||
+      node.dom.tag.toLowerCase() !== "div" ||
+      !TRANSPARENT_ROLES.has(role) ||
+      insideExplicitStructure.has(node.id) ||
+      decisions.get(node.id)?.kind === "excluded" ||
+      node.dom.attrs.hidden !== undefined ||
+      (node.dom.attrs["aria-hidden"] ?? "").toLowerCase() === "true" ||
+      node.dom.attrs.inert !== undefined
+    ) {
+      continue;
+    }
+
+    const branches = (domChildren.get(node.id) ?? []).map((id) => summaries.get(id));
+    const blocked = branches.some((summary) => !summary || summary.blocked);
+    const contributingBranches = branches.filter(
+      (summary) => (summary?.interactions ?? 0) > 0,
+    ).length;
+    const interactions = branches.reduce(
+      (count, summary) => Math.min(2, count + (summary?.interactions ?? 0)),
+      0,
+    );
+    if (!blocked && contributingBranches >= 2 && interactions >= 2) {
+      candidates.add(node.id);
+    }
+  }
+  return candidates;
+}
+
+function leafCandidates(
+  nodes: ResolvedSemanticNode[],
+  candidates: ReadonlySet<SemanticNodeId>,
+  domChildren: ReadonlyMap<SemanticNodeId, SemanticNodeId[]>,
+): Set<SemanticNodeId> {
+  const parentById = new Map(
+    nodes.flatMap((node) => (node.domParentId ? ([[node.id, node.domParentId]] as const) : [])),
+  );
+  const childCount = new Map(nodes.map((node) => [node.id, domChildren.get(node.id)?.length ?? 0]));
+  const containsCandidate = new Set<SemanticNodeId>();
+  const queue = nodes.filter((node) => (childCount.get(node.id) ?? 0) === 0).map((node) => node.id);
+  const selected = new Set<SemanticNodeId>();
+  for (let index = 0; index < queue.length; index += 1) {
+    const nodeId = queue[index];
+    if (candidates.has(nodeId) && !containsCandidate.has(nodeId)) selected.add(nodeId);
+    const parentId = parentById.get(nodeId);
+    if (!parentId) continue;
+    if (candidates.has(nodeId) || containsCandidate.has(nodeId)) containsCandidate.add(parentId);
+    const remaining = (childCount.get(parentId) ?? 1) - 1;
+    childCount.set(parentId, remaining);
+    if (remaining === 0) queue.push(parentId);
+  }
+  return selected;
+}
+
+function nearestKept(
+  graph: ResolvedSemanticGraph,
+  startId: SemanticNodeId | undefined,
+  relation: "axParentId" | "domParentId",
+  kept: ReadonlySet<SemanticNodeId>,
+  memo: Map<SemanticNodeId, SemanticNodeId | undefined>,
+): SemanticNodeId | undefined {
+  let currentId = startId;
+  const path: SemanticNodeId[] = [];
+  const seen = new Set<SemanticNodeId>();
+  let result: SemanticNodeId | undefined;
+  while (currentId && !seen.has(currentId)) {
+    if (kept.has(currentId)) {
+      result = currentId;
+      break;
+    }
+    if (memo.has(currentId)) {
+      result = memo.get(currentId);
+      break;
+    }
+    seen.add(currentId);
+    path.push(currentId);
+    currentId = graph.nodes.get(currentId)?.[relation];
+  }
+  for (const id of path) memo.set(id, result);
+  return result;
+}
+
+function finalParentId(
+  graph: ResolvedSemanticGraph,
+  node: ResolvedSemanticNode,
+  kept: ReadonlySet<SemanticNodeId>,
+  decisions: ReadonlyMap<SemanticNodeId, StructureDecision>,
+  axParentMemo: Map<SemanticNodeId, SemanticNodeId | undefined>,
+  domParentMemo: Map<SemanticNodeId, SemanticNodeId | undefined>,
+): SemanticNodeId | undefined {
+  const axParent = nearestKept(graph, node.axParentId, "axParentId", kept, axParentMemo);
+  const domParent = nearestKept(graph, node.domParentId, "domParentId", kept, domParentMemo);
+  const axNode = axParent ? graph.nodes.get(axParent) : undefined;
+  const domNode = domParent ? graph.nodes.get(domParent) : undefined;
+  const axIsRoot = ROOT_ROLES.has(axNode?.vom.role?.toLowerCase() ?? "");
+  const axIsExplicit = axNode ? explicitStructural(axNode) && !axIsRoot : false;
+  const domIsStructural =
+    domNode !== undefined &&
+    (explicitStructural(domNode) || decisions.get(domNode.id)?.kind === "inferred-group");
+  if (axIsExplicit) return axParent;
+  if (domIsStructural) return domParent;
+  if (axParent && !axIsRoot) return axParent;
+  if (domParent) return domParent;
+  if (axParent) return axParent;
+  if (node.frameId === graph.rootFrameId) return undefined;
+  return graph.frames.get(node.frameId)?.ownerNodeId;
+}
+
+function recoveredVom(node: VomNode, inferredGroup: boolean): ResolvedSemanticNode["vom"] {
+  const {
+    id: _id,
+    parentId: _parentId,
+    backendNodeId: _backendNodeId,
+    frameId: _frameId,
+    contextScopeId: _contextScopeId,
+    referenceable: _referenceable,
+    ...vom
+  } = node;
+  if (!inferredGroup) return vom;
+  const { name: _name, text: _text, nearbyText: _nearbyText, ...groupVom } = vom;
+  return { ...groupVom, role: "group" };
+}
+
+export function normalizeSemanticStructure(graph: ResolvedSemanticGraph): StructuredSemanticGraph {
+  const nodes = orderedNodes(graph);
+  const recovered = recoveredNodes(graph, nodes);
+  const redundant = redundantSourceNodes(graph, nodes, recovered);
+  const frameOwnerIds = new Set(
+    [...graph.frames.values()].flatMap((frame) => frame.ownerNodeId ?? []),
+  );
+  const decisions = new Map<SemanticNodeId, StructureDecision>();
+  for (const node of nodes) {
+    decisions.set(
+      node.id,
+      baseDecision(graph, node, recovered.get(node.id) as VomNode, frameOwnerIds, redundant),
+    );
+  }
+
+  const domChildren = buildChildren(nodes, "domParentId");
+  const candidates = reliableGroupCandidates(graph, nodes, recovered, decisions, domChildren);
+  for (const nodeId of leafCandidates(nodes, candidates, domChildren)) {
+    decisions.set(nodeId, {
+      kind: "inferred-group",
+      reason: "independent-interaction-branches",
+    });
+  }
+
+  const kept = new Set(
+    nodes
+      .filter((node) => {
+        const kind = decisions.get(node.id)?.kind;
+        return kind === "keep" || kind === "inferred-group";
+      })
+      .map((node) => node.id),
+  );
+  const axParentMemo = new Map<SemanticNodeId, SemanticNodeId | undefined>();
+  const domParentMemo = new Map<SemanticNodeId, SemanticNodeId | undefined>();
+  const structuredNodes = new Map<SemanticNodeId, StructuredSemanticNode>();
+  for (const node of nodes) {
+    const structure = decisions.get(node.id) as StructureDecision;
+    const inferredGroup = structure.kind === "inferred-group";
+    structuredNodes.set(node.id, {
+      ...node,
+      vom: recoveredVom(recovered.get(node.id) as VomNode, inferredGroup),
+      structure,
+      ...(kept.has(node.id)
+        ? {
+            semanticParentId: finalParentId(
+              graph,
+              node,
+              kept,
+              decisions,
+              axParentMemo,
+              domParentMemo,
+            ),
+          }
+        : {}),
+    });
+  }
+  return { ...graph, nodes: structuredNodes };
+}
@@ -0,0 +1,88 @@
+import type { Viewport, VomNode } from "@browser-skill/vom";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import type { CapturedNode } from "../capture";
+
+export interface SemanticAxNode {
+  nodeId: string;
+  frameId?: string;
+  parentId?: string;
+  backendDOMNodeId?: number;
+  ignored?: boolean;
+  role?: { type: string; value?: string };
+  name?: { type: string; value?: string };
+  description?: { value?: string };
+  value?: { value?: string | number | boolean };
+  properties?: Array<{ name?: string; value?: { value?: string | number | boolean } }>;
+  childIds?: string[];
+}
+
+export type SemanticNodeId = string;
+
+export interface SemanticFrame {
+  frameId: string;
+  parentFrameId?: string;
+  ownerBackendNodeId?: number;
+  ownerNodeId?: SemanticNodeId;
+  contextScopeId: string;
+  target: CdpTarget;
+  url?: string;
+  order: number;
+}
+
+export interface SemanticGraphNode {
+  id: SemanticNodeId;
+  frameId: string;
+  backendNodeId?: number;
+  axNodeId?: string;
+  ax?: SemanticAxNode;
+  dom?: CapturedNode;
+  axParentId?: SemanticNodeId;
+  domParentId?: SemanticNodeId;
+  sourceOrder: number;
+  excluded: boolean;
+}
+
+export interface SemanticGraph {
+  viewport: Viewport;
+  rootFrameId: string;
+  frames: Map<string, SemanticFrame>;
+  nodes: Map<SemanticNodeId, SemanticGraphNode>;
+  nodeIdsByFrame: Map<string, SemanticNodeId[]>;
+  nodeByFrameBackend: Map<string, SemanticNodeId>;
+}
+
+export interface ResolvedSemanticNode extends SemanticGraphNode {
+  vom: Omit<VomNode, "id" | "parentId" | "backendNodeId" | "frameId" | "contextScopeId">;
+  referenceable: boolean;
+  roleSource: "ax" | "ax-ignored" | "dom-explicit" | "dom-native" | "none";
+}
+
+export interface ResolvedSemanticGraph extends Omit<SemanticGraph, "nodes"> {
+  nodes: Map<SemanticNodeId, ResolvedSemanticNode>;
+}
+
+export type StructureDecision =
+  | { kind: "keep"; reason: "semantic" | "frame-owner" }
+  | { kind: "inferred-group"; reason: "independent-interaction-branches" }
+  | { kind: "transparent"; reason: "wrapper" | "child-document-root" | "ax-ignored" }
+  | {
+      kind: "excluded";
+      reason: "excluded" | "redundant-source" | "non-rendered-dom-fallback";
+    };
+
+export interface StructuredSemanticNode extends ResolvedSemanticNode {
+  structure: StructureDecision;
+  semanticParentId?: SemanticNodeId;
+}
+
+export interface StructuredSemanticGraph extends Omit<ResolvedSemanticGraph, "nodes"> {
+  nodes: Map<SemanticNodeId, StructuredSemanticNode>;
+}
+
+export function frameBackendKey(frameId: string, backendNodeId: number): string {
+  return `${frameId}\u0000${backendNodeId}`;
+}
+
+export function frameAxKey(frameId: string, axNodeId: string): string {
+  return `${frameId}\u0000${axNodeId}`;
+}
@@ -0,0 +1,43 @@
+import { describe, expect, it } from "vitest";
+import {
+  DEFAULT_DAEMON_PORT,
+  normalizeDaemonPort,
+  parseDaemonPortInput,
+  resolveDaemonWsUrl,
+} from "../daemon-endpoint";
+
+describe("daemon-endpoint", () => {
+  it("resolveDaemonWsUrl(DEFAULT) matches the build-time constant", () => {
+    expect(resolveDaemonWsUrl(DEFAULT_DAEMON_PORT)).toBe(__BSK_DAEMON_WS_URL__);
+  });
+
+  it("resolveDaemonWsUrl replaces only the port", () => {
+    expect(resolveDaemonWsUrl(53200)).toBe("ws://127.0.0.1:53200");
+  });
+
+  it("normalizeDaemonPort falls back to default for invalid values", () => {
+    expect(normalizeDaemonPort(undefined)).toBe(DEFAULT_DAEMON_PORT);
+    expect(normalizeDaemonPort(0)).toBe(DEFAULT_DAEMON_PORT);
+    expect(normalizeDaemonPort(65536)).toBe(DEFAULT_DAEMON_PORT);
+    expect(normalizeDaemonPort("abc")).toBe(DEFAULT_DAEMON_PORT);
+    expect(normalizeDaemonPort(1.5)).toBe(DEFAULT_DAEMON_PORT);
+  });
+
+  it("normalizeDaemonPort accepts valid numbers and numeric strings", () => {
+    expect(normalizeDaemonPort(53200)).toBe(53200);
+    expect(normalizeDaemonPort("53200")).toBe(53200);
+  });
+
+  it("parseDaemonPortInput treats empty as default and rejects invalid", () => {
+    expect(parseDaemonPortInput("")).toBe(DEFAULT_DAEMON_PORT);
+    expect(parseDaemonPortInput("   ")).toBe(DEFAULT_DAEMON_PORT);
+    expect(parseDaemonPortInput("abc")).toBeNull();
+    expect(parseDaemonPortInput("0")).toBeNull();
+    expect(parseDaemonPortInput("65536")).toBeNull();
+  });
+
+  it("parseDaemonPortInput accepts valid ports", () => {
+    expect(parseDaemonPortInput("53200")).toBe(53200);
+    expect(parseDaemonPortInput(" 52800 ")).toBe(52800);
+  });
+});
@@ -65,6 +65,11 @@ function deferredFakeTransport(): { transport: Transport; emit: (frame: Protocol
 }

 describe("performHandshake", () => {
+  it("advertises the protocol compatibility boundary", () => {
+    expect(PROTOCOL_VERSION).toBe("1.1");
+    expect(MIN_COMPATIBLE_PROTOCOL).toBe("1.0");
+  });
+
  it("sends system.handshake with identity and both compat fields", async () => {
    let sentFrame: ProtocolFrame | null = null;
    const transport = fakeTransport((req) => {
@@ -74,7 +79,7 @@ describe("performHandshake", () => {
        result: {
          server: "browser-skill-daemon",
          version: "0.1.0",
-          protocol_version: "1.0",
+          protocol_version: "1.1",
          min_compatible_peer: "0.0.0",
          min_compatible_protocol: "1.0",
        },
@@ -129,8 +134,8 @@ describe("performHandshake", () => {
    const response = {
      server: "browser-skill-daemon",
      version: "0.1.0",
-      protocol_version: "1.0",
-      min_compatible_protocol: "1.0",
+      protocol_version: "1.1",
+      min_compatible_protocol: "1.1",
    } satisfies HandshakeResult;
    const transport = fakeTransport((req) => ({
      id: (req as { id: string }).id,
@@ -145,7 +150,7 @@ describe("performHandshake", () => {
    });

    expect(outcome.result.min_compatible_peer).toBeUndefined();
-    expect(outcome.result.min_compatible_protocol).toBe("1.0");
+    expect(outcome.result.min_compatible_protocol).toBe("1.1");
  });

  it("rejects when the daemon responds with an error", async () => {
@@ -178,9 +183,9 @@ describe("performHandshake", () => {
      result: {
        server: "browser-skill-daemon",
        version: "0.1.0",
-        protocol_version: "1.0",
+        protocol_version: "1.1",
        min_compatible_peer: "0.0.0",
-        min_compatible_protocol: "1.0",
+        min_compatible_protocol: "1.1",
      },
    });
    emit({
@@ -188,14 +193,14 @@ describe("performHandshake", () => {
      result: {
        server: "browser-skill-daemon",
        version: "0.1.0",
-        protocol_version: "1.0",
+        protocol_version: "1.1",
        min_compatible_peer: "0.0.0",
-        min_compatible_protocol: "1.0",
+        min_compatible_protocol: "1.1",
      },
    });

    await expect(pending).resolves.toMatchObject({
-      result: { server: "browser-skill-daemon", protocol_version: "1.0" },
+      result: { server: "browser-skill-daemon", protocol_version: "1.1" },
    });
  });

@@ -270,4 +270,19 @@ describe("WSTransport", () => {
    lastSocket().receive({ id: "2", result: 2 });
    expect(handler).toHaveBeenCalledTimes(1);
  });
+
+  it("setUrl returns false for the same URL and uses the new URL on the next connect", async () => {
+    const t = new WSTransport({
+      url: "ws://127.0.0.1:52800",
+      webSocketFactory: (url) => new FakeSocket(url) as unknown as WebSocket,
+    });
+    expect(t.setUrl("ws://127.0.0.1:52800")).toBe(false);
+    expect(t.setUrl("ws://127.0.0.1:53200")).toBe(true);
+
+    const p = t.connect();
+    expect(lastSocket().url).toBe("ws://127.0.0.1:53200");
+    lastSocket().open();
+    await p;
+    expect(t.state).toBe("connected");
+  });
 });
--- a/Show More
+++ b/Show More