fix(record): saftey policy and rebase bug fix

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

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

@@ -1,10 +1,12 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
-import { RECORD_STOP, type RecordStepPayload } from "@/lib/record-bridge";
+import { RECORD_START, RECORD_STOP, type RecordStepPayload } from "@/lib/record-bridge";
 import { handleRecordContentMessage, 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 }),
+    ),
   },
 });
 
@@ -96,6 +98,66 @@ describe("handleRecordContentMessage stop/cancel", () => {
     expect(dispose).not.toHaveBeenCalled();
     expect(onStop).not.toHaveBeenCalled();
   });
+
+  it("keeps a failed STOP retryable and redelivers its recorded step", async () => {
+    document.body.innerHTML = `<label for="retry">Draft</label><input id="retry" />`;
+    const sendMessage = vi.mocked(chrome.runtime.sendMessage);
+    sendMessage.mockReset();
+    sendMessage.mockRejectedValueOnce(new Error("service worker unavailable"));
+    sendMessage.mockRejectedValueOnce(new Error("service worker still unavailable"));
+    sendMessage.mockResolvedValueOnce({ ok: true, sequence: 1 });
+
+    let activeRequestId: string | null = null;
+    let capture: ReturnType<typeof startRecordCapture> | null = null;
+    const onStop = vi.fn();
+    const dispatch = (
+      message:
+        | { type: typeof RECORD_START; requestId: string; startedAtMs?: number }
+        | { type: typeof RECORD_STOP; requestId: string },
+      sendResponse?: (response: unknown) => void,
+    ) =>
+      handleRecordContentMessage(
+        message,
+        {
+          activeRequestId,
+          capture,
+          setActiveRequestId: (id) => {
+            activeRequestId = id;
+          },
+          setCapture: (next) => {
+            capture = next;
+          },
+          onStart: vi.fn(),
+          onStop,
+        },
+        sendResponse,
+      );
+
+    dispatch({ type: RECORD_START, requestId: "rec-retry" });
+    const input = document.querySelector("input")!;
+    input.dispatchEvent(new FocusEvent("focusin", { bubbles: true }));
+    input.value = "dirty final value";
+    input.dispatchEvent(new Event("input", { bubbles: true }));
+
+    const firstResponse = vi.fn();
+    expect(dispatch({ type: RECORD_STOP, requestId: "rec-retry" }, firstResponse)).toBe(true);
+    await vi.waitFor(() =>
+      expect(firstResponse).toHaveBeenCalledWith({
+        ok: false,
+        error: "failed to deliver one or more recorded steps",
+      }),
+    );
+    expect(activeRequestId).toBe("rec-retry");
+    expect(onStop).not.toHaveBeenCalled();
+
+    const retryResponse = vi.fn();
+    expect(dispatch({ type: RECORD_STOP, requestId: "rec-retry" }, retryResponse)).toBe(true);
+    await vi.waitFor(() => expect(retryResponse).toHaveBeenCalledWith({ ok: true }));
+
+    expect(sendMessage).toHaveBeenCalledTimes(3);
+    expect(activeRequestId).toBeNull();
+    expect(onStop).toHaveBeenCalledTimes(1);
+  });
 });
 
 describe("record-capture semantic", () => {
@@ -228,6 +290,7 @@ 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",

apps/extension/src/content/__tests__/record-step-delivery.test.ts

@@ -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);
+  });
+});

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

@@ -1,9 +1,9 @@
 import {
+  type CaptureTargetDescriptor,
   describeEventTarget,
   describeTarget,
   resolveClickableElement,
   resolveHoverElement,
-  type TargetDescriptor,
 } from "@/lib/describe-target";
 import {
   evaluateHoverTrigger,
@@ -27,7 +27,7 @@ import {
   type RecordStopAck,
   type RecordStopMessage,
 } from "@/lib/record-bridge";
-import { shouldRecordPress } from "@/lib/trace-reducer";
+import { shouldRecordPress } from "@/lib/recording/draft-policy";
 import {
   closestHoverSurfaceCandidate,
   collectHoverSurfaceStates,
@@ -36,27 +36,17 @@ import {
   isHoverSurfaceCandidateElement,
   isLikelyHoverSurfaceOwner,
 } from "./record-hover-surface";
+import { RecordStepDelivery } from "./record-step-delivery";
 
-const pendingStepSends = new Map<string, Set<Promise<boolean>>>();
-const failedStepDeliveries = new Set<string>();
-const knownRecordRequests = new Set<string>();
+const stepDeliveries = new Map<string, RecordStepDelivery>();
+const pendingStopFlushes = new Map<string, Promise<RecordStopAck>>();
 
-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);
-  });
+function deliveryFor(requestId: string): RecordStepDelivery {
+  const existing = stepDeliveries.get(requestId);
+  if (existing) return existing;
+  const created = new RecordStepDelivery(requestId);
+  stepDeliveries.set(requestId, created);
+  return created;
 }
 
 export interface RecordCaptureController {
@@ -65,14 +55,15 @@ export interface RecordCaptureController {
 
 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 +148,24 @@ 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 +241,10 @@ 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 +262,7 @@ 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 +273,9 @@ 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 +289,7 @@ 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 {
@@ -411,14 +423,17 @@ 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 +639,7 @@ export function startRecordCapture(
     emitStep({
       op: "hover",
       target: hover.target,
+      geometry: captureGeometry(hover.element),
     });
     emittedHoverElements.add(hover.element);
   };
@@ -678,6 +694,7 @@ export function startRecordCapture(
     emitStep({
       op: "click",
       target,
+      geometry: geometryForEventTarget(eventTarget(event)),
       expects_navigation: true,
     });
   };
@@ -779,7 +796,7 @@ export function startRecordCapture(
       scheduleInputCompletionCommit(
         sessionElement,
         syncFillSessionValue,
-        commitFillSession,
+        () => commitFillSession("suggestion"),
         (el) => fillSession?.element === el,
       );
       return;
@@ -839,6 +856,7 @@ export function startRecordCapture(
       emitStep({
         op: "select",
         target: desc,
+        geometry: captureGeometry(target),
         values,
         labels,
         expects_navigation: true,
@@ -879,7 +897,7 @@ export function startRecordCapture(
       };
     }
     if (fillable) {
-      commitFillSession();
+      commitFillSession(event.key === "Enter" ? "enter" : "blur");
     }
     const desc = describeEventTarget(target);
     if (!desc && !event.key) return;
@@ -887,7 +905,7 @@ 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",
     });
@@ -906,9 +924,12 @@ export function startRecordCapture(
   const urlObserver = new MutationObserver(() => emitNavigateIfChanged());
   urlObserver.observe(document, { subtree: true, childList: true });
   const onUrlEvent = () => emitNavigateIfChanged();
+  // Wrap: passing commitFillSession directly would forward the DOM event as
+  // the `commit` argument and stamp it onto the recorded fill step.
+  const onPageHide = () => commitFillSession();
   window.addEventListener("hashchange", onUrlEvent);
   window.addEventListener("popstate", onUrlEvent);
-  window.addEventListener("pagehide", commitFillSession);
+  window.addEventListener("pagehide", onPageHide);
 
   const originalPushState = history.pushState;
   const originalReplaceState = history.replaceState;
@@ -936,7 +957,7 @@ export function startRecordCapture(
       urlObserver.disconnect();
       window.removeEventListener("hashchange", onUrlEvent);
       window.removeEventListener("popstate", onUrlEvent);
-      window.removeEventListener("pagehide", commitFillSession);
+      window.removeEventListener("pagehide", onPageHide);
       history.pushState = originalPushState;
       history.replaceState = originalReplaceState;
     },
@@ -962,14 +983,11 @@ export function handleRecordContentMessage(
   sendResponse?: (response: RecordStartAck | RecordStopAck) => void,
 ): boolean {
   if (isRecordStartMessage(message)) {
-    if (!knownRecordRequests.has(message.requestId)) {
-      knownRecordRequests.add(message.requestId);
-      failedStepDeliveries.delete(message.requestId);
-    }
+    const delivery = deliveryFor(message.requestId);
     state.capture?.dispose();
     state.setCapture(
       startRecordCapture(message.requestId, (step) => {
-        sendRecordStep(message.requestId, step);
+        delivery.enqueue(step);
       }),
     );
     state.setActiveRequestId(message.requestId);
@@ -992,28 +1010,37 @@ export function handleRecordContentMessage(
       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
+      const existingFlush = pendingStopFlushes.get(message.requestId);
+      if (existingFlush) {
+        void existingFlush.then(sendResponse);
+        return true;
+      }
+
+      const flush = deliveryFor(message.requestId)
+        .flush()
+        .then((succeeded): RecordStopAck => {
+          if (succeeded) {
+            stepDeliveries.delete(message.requestId);
+            finishStop();
+          }
+          return succeeded
             ? { ok: true }
             : {
                 ok: false,
                 error: "failed to deliver one or more recorded steps",
-              },
-        );
+              };
+        });
+      pendingStopFlushes.set(message.requestId, flush);
+      void flush.then(sendResponse).finally(() => {
+        if (pendingStopFlushes.get(message.requestId) === flush) {
+          pendingStopFlushes.delete(message.requestId);
+        }
       });
       return true;
     }
     if (isRecordCancelMessage(message)) {
-      failedStepDeliveries.delete(message.requestId);
-      knownRecordRequests.delete(message.requestId);
+      stepDeliveries.delete(message.requestId);
+      pendingStopFlushes.delete(message.requestId);
     }
     finishStop();
     return false;

apps/extension/src/content/record-step-delivery.ts

@@ -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;
+      }
+    }
+  }
+}

apps/extension/src/entrypoints/background.ts

@@ -172,6 +172,7 @@ export default defineBackground(() => {
   dispatcher.start();
   const recordDeps = {
     tabsApi: chrome.tabs,
+    cdp,
     sendToTab: (tabId: number, msg: Parameters<typeof chrome.tabs.sendMessage>[1]) =>
       chrome.tabs.sendMessage(tabId, msg),
     bypassOverlay: async (tabId: number, enabled: boolean) => {
@@ -188,7 +189,7 @@ export default defineBackground(() => {
   // 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();
+  attachRecordStepListener(recordDeps);
   attachRecordFinishListener(recordDeps);
   attachRecordQueryListener(recordDeps);
   if (typeof chrome.notifications?.onClicked?.addListener === "function") {

apps/extension/src/entrypoints/popup/App.test.tsx

@@ -200,6 +200,9 @@ 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"));

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

@@ -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"));
   });
 });

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

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

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

@@ -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,
+    );
+  });
+});

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

@@ -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,
+    });
+  });
+});

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

@@ -0,0 +1,152 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+
+const captureRecordingObservation = vi.hoisted(() => vi.fn());
+
+vi.mock("../recording/observation-capture", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../recording/observation-capture")>();
+  return { ...actual, captureRecordingObservation };
+});
+
+import { ObservationNodeIndex } from "../recording/observation-capture";
+import { RecordingObservationRuntime } from "../recording/recording-runtime";
+
+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());
+
+  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]);
+  });
+});

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

@@ -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",
-    });
-  });
-});

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

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

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

@@ -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" });
+  });
+});

apps/extension/src/lib/__tests__/tab-coordinator.test.ts

@@ -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");
+  });
+});

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

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

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

@@ -1,6 +1,15 @@
 import { describe, expect, it } from "vitest";
-import type { DraftTraceStep } from "@/transport/types";
-import { reduceTraceSteps, resolveTraceStartUrl, shouldRecordPress } from "../trace-reducer";
+import type { RecordingDraftStep } from "@/lib/recording/types";
+import { shouldRecordPress } from "../recording/draft-policy";
+import { buildTraceV2 } from "../recording/trace-reducer-v2";
+
+function reduceTraceSteps(steps: RecordingDraftStep[], startUrl?: string) {
+  return buildTraceV2({
+    steps,
+    startedAt: "2026-01-01T00:00:00.000Z",
+    ...(startUrl ? { startUrl } : {}),
+  });
+}
 
 describe("shouldRecordPress", () => {
   it("keeps Enter and Escape", () => {
@@ -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");
   });
 });

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

@@ -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 },
+    });
+  });
+});

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

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

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

@@ -3,7 +3,7 @@
  * service worker and a tab's content script.
  */
 
-import type { TargetDescriptor } from "./describe-target";
+import type { CaptureTargetDescriptor } from "./describe-target";
 
 export const RECORD_START = "bsk-record-start";
 export const RECORD_STEP = "bsk-record-step";
@@ -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;
+}

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

@@ -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;
-  }
-}

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

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

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

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

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

@@ -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));
+}

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

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

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

@@ -0,0 +1,128 @@
+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) }
+        : {}),
+    });
+  }
+}

apps/extension/src/lib/recording/recording-runtime.ts

@@ -0,0 +1,219 @@
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import type { StopReason, TraceV3 } from "@/transport/types";
+import type { DocumentSettleScope } 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;
+}
+
+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,
+    };
+    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);
+  }
+
+  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,
+    scope?: DocumentSettleScope,
+  ): 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.
+      }
+    }
+    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> {
+    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.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,
+    });
+  }
+}

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

@@ -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");
+  }
+}

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

@@ -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);
+  }
+}

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

@@ -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;
+}

apps/extension/src/lib/recording/tab-coordinator.ts

@@ -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;
+  }
+}

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

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

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

@@ -0,0 +1,92 @@
+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,
+  };
+}

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

@@ -1,30 +1,10 @@
-import type { DraftTraceStep, PageRefV2, SelectedOptionV2, StepV2 } 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[] = [];
@@ -58,7 +38,7 @@ function collectUrls(steps: DraftTraceStep[], startUrl?: string): string[] {
 }
 
 function buildPageRegistry(
-  steps: DraftTraceStep[],
+  steps: RecordingDraftStep[],
   startUrl?: string,
 ): { pages: PageRefV2[]; urlToId: Map<string, string> } {
   const urls = collectUrls(steps, startUrl);
@@ -81,9 +61,9 @@ 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;
 }
 
@@ -110,7 +90,7 @@ function toSelection(values: string[], labels?: string[]): SelectedOptionV2[] {
 }
 
 function toV2Step(
-  step: DraftTraceStep,
+  step: RecordingDraftStep,
   id: number,
   urlToId: Map<string, string>,
   fallbackUrl?: string,
@@ -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 } : {}),
       };
@@ -161,26 +136,33 @@ 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 {
+interface ReducedTrace {
   pages: PageRefV2[];
   steps: StepV2[];
 }
@@ -189,7 +171,7 @@ export interface ReducedTrace {
  * 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: StepV2[] = [];
@@ -197,8 +179,8 @@ export function reduceTraceSteps(steps: DraftTraceStep[], startUrl?: string): Re
   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?: PageRefV2[],
 ): string {
-  if (startUrl) return startUrl;
-  const navigate = drafts.find((step): step is Extract<DraftTraceStep, { op: "navigate" }> => {
-    return step.op === "navigate";
-  });
-  if (navigate) return navigate.url;
-  for (const draft of drafts) {
-    if ("page_url" in draft && draft.page_url) return draft.page_url;
-  }
-  return pages?.[0]?.url ?? "about:blank";
+  return resolveDraftStartUrl(drafts, startUrl, pages?.[0]?.url);
+}
+
+export function buildTraceV2(input: {
+  steps: RecordingDraftStep[];
+  startedAt: string;
+  startUrl?: string;
+  purpose?: string;
+}): TraceV2 {
+  const { pages, steps } = reduceTraceSteps(input.steps, input.startUrl);
+  return {
+    recorded_at: new Date().toISOString(),
+    started_at: input.startedAt,
+    ...(input.purpose ? { purpose: input.purpose } : {}),
+    entry: { start_url: resolveTraceStartUrl(input.steps, input.startUrl, pages) },
+    pages,
+    steps,
+  };
 }

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

@@ -0,0 +1,154 @@
+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 };
+}

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

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

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

@@ -0,0 +1,84 @@
+import type { CaptureTargetDescriptor } from "@/lib/describe-target";
+import type {
+  FillCommit,
+  KeyModifier,
+  NavigationCause,
+  StepV3,
+  TargetDescriptorV3,
+} from "@/transport/types";
+
+export interface TargetGeometry {
+  /** Top-level viewport-relative CSS pixels, as defined by the geometry module. */
+  rect: { x: number; y: number; w: number; h: number };
+  tag: string;
+}
+
+export interface TargetMatchHint {
+  geometry?: TargetGeometry;
+  /** Missing means the current top frame, never an unrestricted frame search. */
+  frameId?: string;
+}
+
+export interface StepAnnotation {
+  draftId: number;
+  op: StepV3["op"];
+  line: number;
+  stateId: string;
+  detail?: string;
+}
+
+interface DraftStateLink {
+  pageUrl?: string;
+  preStateId?: string;
+  postStateId?: string;
+}
+
+interface DraftTarget {
+  captureTarget?: CaptureTargetDescriptor;
+  targetHint?: TargetMatchHint;
+  matchedTarget?: TargetDescriptorV3;
+}
+
+interface DraftNavigationEffect {
+  navigatedTo?: string;
+}
+
+export type RecordingDraftStep =
+  | ({ op: "click" } & DraftStateLink & DraftTarget & DraftNavigationEffect)
+  | ({ op: "hover" } & DraftStateLink & DraftTarget)
+  | ({
+      op: "fill";
+      value: string;
+      commit?: FillCommit;
+      redacted?: boolean;
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({
+      op: "press";
+      key: string;
+      modifiers?: KeyModifier[];
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({
+      op: "select";
+      values: string[];
+      labels?: string[];
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({ op: "scroll" } & DraftStateLink)
+  | ({ op: "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" }
+>;

apps/extension/src/tools/record.ts

@@ -15,22 +15,32 @@ 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 { 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,
-  TraceV2,
+  StopReason,
 } from "@/transport/types";
+import { TRACE_VERSION_V3 } from "@/transport/types";
 import { handleNavigate } from "./navigation";
 import {
   type CdpRunner,
@@ -43,21 +53,46 @@ 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<TraceV2>;
-  resolveFinish: (trace: TraceV2) => 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 +113,9 @@ 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 +175,11 @@ 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 +187,7 @@ 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 +195,82 @@ async function sendRecordStartWithAck(
   throw lastError ?? new Error("failed to start recording in content script");
 }
 
-function buildTrace(recording: ActiveRecording): TraceV2 {
-  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,
+): Promise<void> {
+  if (!recording.observation) return;
+  try {
+    await recording.observation.processDraft(tabId, recording.steps, draftIndex);
+  } catch (err) {
+    console.warn(`[bsk record] observation failed for step ${draftIndex + 1}`, err);
+  }
+}
+
 export interface RecordDeps {
   tabsApi: ChromeTabsApi;
   sendToTab(
@@ -241,16 +345,52 @@ 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 sourceTabId = sender.tab?.id ?? recording.tabs.currentTabId;
+      const sourceWasActive = sender.tab?.active ?? sourceTabId === recording.tabs.activeTabId;
+      const producerKey = `${sourceTabId}:${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);
+        }
+      });
+      sendResponse({ ok: true, sequence: message.sequence });
       return false;
     }
     return false;
@@ -277,7 +417,7 @@ 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 +454,7 @@ 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) {
@@ -330,12 +470,12 @@ async function stopRecordingOnAllAgentTabs(
   deps: RecordDeps,
 ): Promise<void> {
   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 +486,11 @@ 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 +508,35 @@ 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;
+      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 +545,7 @@ 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 +554,7 @@ 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 +566,20 @@ 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 +591,47 @@ 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 +651,13 @@ 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 +675,26 @@ 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 +713,8 @@ 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 +736,50 @@ 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<TraceV2 | 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 +794,15 @@ 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 +819,53 @@ 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: TraceV2) => void;
+  let resolveFinish!: (trace: RecordedTrace) => void;
   let rejectFinish!: (err: Error) => void;
-  const finishPromise = new Promise<TraceV2>((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(),
   });
   // 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();
     recordings.delete(params.session_id);
     releaseBrowserObservationListenersIfIdle();
     if (notifyContent) {
@@ -686,7 +947,7 @@ 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 +955,7 @@ 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`,
     };
   }
 
@@ -731,6 +992,17 @@ 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 +1027,7 @@ 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 +1057,9 @@ export async function handleRecordAwait(
     return { code: "cancelled", message: "record_await aborted" };
   }
 
-  const outcome = await new Promise<{ trace: TraceV2 } | { error: RpcError }>((resolve) => {
+  const outcome = await new Promise<{ trace: RecordedTrace } | { error: RpcError }>((resolve) => {
     let settled = false;
-    const finish = (result: { trace: TraceV2 } | { error: RpcError }) => {
+    const finish = (result: { trace: RecordedTrace } | { error: RpcError }) => {
       if (settled) return;
       settled = true;
       if (timer) clearTimeout(timer);
@@ -829,6 +1101,7 @@ export function clearRecordingForSession(sessionId: string): void {
   }
   void clearRearmTimersForRecording(recording, getDefaultDeps());
   if (!recording.settled) {
+    recording.observation?.cancel();
     recording.settled = true;
     recording.rejectFinish(new Error("recording cleared"));
   }

apps/extension/src/transport/__tests__/handshake.test.ts

@@ -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" },
     });
   });
 

apps/extension/src/transport/handshake.ts

@@ -7,7 +7,7 @@ import type {
   ResponseFrame,
 } from "./types";
 
-export const PROTOCOL_VERSION = "1.0";
+export const PROTOCOL_VERSION = "1.1";
 /**
  * Extension semver, injected at build time from `package.json` via
  * Vite's `define` (see `wxt.config.ts` and `vitest.config.ts`).

apps/extension/src/transport/types.ts

@@ -744,48 +744,6 @@ export interface StepCommonV2 {
   effect?: StepEffectV2;
 }
 
-/** Capture/buffer draft before v2 reduction. */
-export type DraftTraceStep =
-  | {
-      op: "click";
-      target: TargetDescriptorV2;
-      navigated_to?: string;
-      page_url?: string;
-    }
-  | {
-      op: "hover";
-      target: TargetDescriptorV2;
-      page_url?: string;
-    }
-  | {
-      op: "fill";
-      target: TargetDescriptorV2;
-      value: string;
-      redacted?: boolean;
-      page_url?: string;
-    }
-  | {
-      op: "press";
-      key: string;
-      target?: TargetDescriptorV2;
-      modifiers?: KeyModifier[];
-      navigated_to?: string;
-      page_url?: string;
-    }
-  | {
-      op: "select";
-      target: TargetDescriptorV2;
-      values: string[];
-      labels?: string[];
-      navigated_to?: string;
-      page_url?: string;
-    }
-  | {
-      op: "navigate";
-      url: string;
-      page_url?: string;
-    };
-
 /** Exported record-only step (trace v2). */
 export type StepV2 =
   | ({ op: "navigate" } & StepCommonV2 & { to: string })
@@ -822,6 +780,7 @@ export interface SelectedOptionV3 {
 
 export type StepV3 =
   | ({ op: "navigate" } & StepCommonV3 & { to: string; cause: NavigationCause })
+  | ({ op: "switch_tab" } & StepCommonV3)
   | ({ op: "click" } & StepCommonV3 & { target: TargetDescriptorV3 })
   | ({ op: "hover" } & StepCommonV3 & { target: TargetDescriptorV3 })
   | ({ op: "fill" } & StepCommonV3 & {
@@ -861,6 +820,12 @@ export interface RecordStartParams {
   tab_id?: number;
   url?: string;
   purpose?: string;
+  max_page_tokens?: number;
+  redact_values?: boolean;
+  /** Omitted means v2; `3` requests a state-linked v3 trace. */
+  trace_version?: number;
+  /** Client can decode the v3 `switch_tab` step variant. */
+  supports_tab_switch_steps?: boolean;
 }
 
 export interface RecordStartResult {

crates/bsk-cli/skill/SKILL.md

@@ -265,19 +265,27 @@ retry — complete the task autonomously or stop gracefully.
 
 ### Recording — `bsk record`
 
-Capture the user's own actions in the Agent Window to a `trace.json`, for later LLM-driven automation:
+Capture the user's own actions in the Agent Window to a **trace bundle**, for later LLM-driven automation. New CLI builds request **trace v3** (page observations + action chain); older extensions may still return **trace v2** (actions only), which the CLI exports as a single `trace.json` without `states/`.
 
 ```bash
-bsk record start --browser <instance-id-or-label> [--url https://…] [--purpose "publish a wiki doc"] [--output trace.json]
+bsk record start --browser <instance-id-or-label> \
+  [--url https://…] [--purpose "publish a wiki doc"] \
+  [--max-page-tokens 3000] [--redact-values] \
+  [--output trace]
 # `--url` is optional; default https://example.com/ when omitted (must be http(s)).
-# Blocks until the user clicks Finish in the recording panel, then writes ./trace.json and closes the window.
+# Blocks until the user clicks Finish in the recording panel, then writes:
+#   trace/trace.json    — action chain (+ state index when v3)
+#   trace/states/       — v3 only: one `sN.txt` observe snapshot per settled page state
 
-bsk record stop [--output trace.json]   # terminal fallback if the browser panel is unavailable
+bsk record stop [--output trace]   # terminal fallback if the browser panel is unavailable
 ```
 
-- The trace is a **record-only action log** (a `pages[]` dictionary + `navigate`/`click`/`fill`/`select`/`press` steps with `target` descriptors). It records *what the user did*; deciding which inputs are variable is left to the executing agent.
+- **v3 bundle (preferred):** `--output` is a directory (default `./trace`) containing `trace.json` and `states/`. `trace.json` lists `states[]` (page observation ids) and `steps[]` (each step binds `state` = observe snapshot *before* the action and `result.state` = snapshot *after* settle). Page bodies live in `states/sN.txt` using the same VOM format as `bsk observe`.
+- **v2 fallback:** when the connected extension is older, export may contain only legacy `trace.json` with `pages[]` action context and no `states/` observation files. Update the extension for full v3 bundles.
+- Each `states[]` entry is one **settled page observation** (captured after recording start, navigation landing, or action settle — not on a timer).
+- `target.ref` values like `@e12` exist **only inside** the bundle for disambiguation; do **not** copy `@eN` refs into SKILL.md or agent runbooks — use visible names from the observation text instead.
 - `--purpose` is optional context metadata; it does **not** change what gets captured.
-- There is **no** `bsk replay` — to redo a flow, read the trace and reuse the existing `session` / `snapshot` / `@eN` / `click` / `fill` tools. Follow **Stop when the goal is met**.
+- `--redact-values` masks all form values in page files as `[filled]` / `[empty]`.
 - Do **not** record on banking/SSO/password-manager pages; passwords are redacted but traces may still contain sensitive text.
 
 ## Error handling

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

@@ -22,6 +22,7 @@ pub mod navigate;
 pub mod network;
 pub mod observe;
 pub mod record;
+pub mod record_recovery;
 pub mod record_state;
 pub mod render_error;
 pub mod screenshot;

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

@@ -1,23 +1,30 @@
 //! `bsk record start|stop` — capture user actions in the Agent Window.
 
-use std::fs;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::time::Duration;
 
 use anyhow::Context;
-use bsk_protocol::Method;
 use bsk_protocol::tools::{
     RecordAwaitParams, RecordAwaitResult, RecordStartParams, RecordStartResult, RecordStopParams,
-    RecordStopResult, RecordedTrace,
+    RecordStopResult, RecordedTrace, TRACE_VERSION_V3,
 };
+use bsk_protocol::{ErrorCode, Method};
 use clap::{Args, Subcommand};
 
 use crate::cli::TOOL_IPC_TIMEOUT;
+
+mod export;
+
 use crate::cli::business_rpc;
 use crate::cli::ensure_daemon::ensure_daemon;
 use crate::cli::error::{CliError, Format};
+use crate::cli::record_recovery;
 use crate::cli::record_state;
 use crate::cli::session::{SessionStartOptions, start_session, stop_session};
+use export::{
+    ExportMeta, export_with_recovery, states_dir_for_output, trace_json_path,
+    validate_record_output,
+};
 
 /// Max wait for the user to click 结束 in the browser (24 hours).
 const RECORD_AWAIT_TIMEOUT_MS: u32 = 86_400_000;
@@ -50,7 +57,8 @@ pub struct RecordStartArgs {
     pub tab_id: Option<i64>,
 
     /// Navigate to this http(s) URL before recording. When omitted, defaults
-    /// to `https://example.com/`.
+    /// to `https://example.com/`. If that page does not load, pass `--url`
+    /// with a site you can open in this browser.
     #[arg(long)]
     pub url: Option<String>,
 
@@ -58,15 +66,25 @@ pub struct RecordStartArgs {
     #[arg(long)]
     pub purpose: Option<String>,
 
-    /// Output path for the trace JSON (default `./trace.json`).
-    #[arg(long, default_value = "trace.json")]
+    /// Max VOM tokens per page observation file (default 3000).
+    #[arg(long = "max-page-tokens")]
+    pub max_page_tokens: Option<u32>,
+
+    /// Redact all form values in page observations (`[filled]` only).
+    #[arg(long = "redact-values")]
+    pub redact_values: bool,
+
+    /// Output directory for the trace bundle (default `./trace`).
+    /// Writes `<dir>/trace.json` and `<dir>/states/*.txt`.
+    #[arg(long, default_value = "trace")]
     pub output: PathBuf,
 }
 
 #[derive(Debug, Clone, Args)]
 pub struct RecordStopArgs {
-    /// Output path for the trace JSON (default `./trace.json`).
-    #[arg(long, default_value = "trace.json")]
+    /// Output directory for the trace bundle (default `./trace`).
+    /// Writes `<dir>/trace.json` and `<dir>/states/*.txt`.
+    #[arg(long, default_value = "trace")]
     pub output: PathBuf,
 }
 
@@ -78,11 +96,7 @@ pub fn dispatch(cmd: RecordCmd, format: Format) -> Result<(), CliError> {
 }
 
 fn dispatch_start(args: RecordStartArgs, format: Format) -> Result<(), CliError> {
-    if record_state::read().is_ok() {
-        return Err(CliError::Local(anyhow::anyhow!(
-            "a recording is already in progress; run `bsk record stop` first"
-        )));
-    }
+    prepare_record_start(&args.output)?;
 
     let info = ensure_daemon().context("ensure daemon is running")?;
     let session = start_session(
@@ -96,8 +110,12 @@ fn dispatch_start(args: RecordStartArgs, format: Format) -> Result<(), CliError>
     let start_params = RecordStartParams {
         session_id: session.session_id.clone(),
         tab_id: args.tab_id,
-        url: args.url,
+        url: args.url.clone(),
         purpose: args.purpose.clone(),
+        max_page_tokens: args.max_page_tokens,
+        redact_values: Some(args.redact_values),
+        trace_version: Some(TRACE_VERSION_V3),
+        supports_tab_switch_steps: Some(true),
     };
     let start_result = business_rpc::call::<RecordStartParams, RecordStartResult>(
         info.sock_path.clone(),
@@ -111,7 +129,7 @@ fn dispatch_start(args: RecordStartArgs, format: Format) -> Result<(), CliError>
         Ok(result) => result,
         Err(err) => {
             let _ = stop_session(info.sock_path, &session.session_id);
-            return Err(err);
+            return Err(annotate_default_start_page_error(err, args.url.as_deref()));
         }
     };
 
@@ -142,8 +160,8 @@ fn dispatch_start(args: RecordStartArgs, format: Format) -> Result<(), CliError>
     // Keep write/render inside a Result so `?` cannot skip session teardown.
     let run_result: Result<(), CliError> = match await_result {
         Ok(result) => (|| {
-            write_trace_file(&args.output, &result.trace)?;
-            render_finish(&result.trace, &args.output, format)
+            let exported = export_with_recovery(&args.output, &result.trace)?;
+            render_finish(&result.trace, &args.output, &exported, format)
         })(),
         Err(err) => Err(err),
     };
@@ -157,11 +175,12 @@ fn dispatch_start(args: RecordStartArgs, format: Format) -> Result<(), CliError>
 }
 
 fn dispatch_stop(args: RecordStopArgs, format: Format) -> Result<(), CliError> {
-    let state = record_state::read().map_err(CliError::Local)?;
-    let info = ensure_daemon().context("ensure daemon is running")?;
-    let session_id = state.session_id.clone();
+    validate_record_output(&args.output)?;
+
+    if let Ok(state) = record_state::read() {
+        let info = ensure_daemon().context("ensure daemon is running")?;
+        let session_id = state.session_id.clone();
 
-    let run_result: Result<(), CliError> = (|| {
         let params = RecordStopParams {
             session_id: session_id.clone(),
         };
@@ -172,16 +191,85 @@ fn dispatch_stop(args: RecordStopArgs, format: Format) -> Result<(), CliError> {
             Some(params),
             TOOL_IPC_TIMEOUT,
         )?;
-        write_trace_file(&args.output, &result.trace)?;
-        render_stop(&result, &args.output, format)
-    })();
 
-    let session_stop_result = stop_session(info.sock_path, &session_id);
-    record_state::clear();
+        let run_result: Result<(), CliError> = (|| {
+            let exported = export_with_recovery(&args.output, &result.trace)?;
+            render_stop(&result, &args.output, &exported, format)
+        })();
 
-    run_result?;
-    session_stop_result?;
-    Ok(())
+        let session_stop_result = stop_session(info.sock_path, &session_id);
+        record_state::clear();
+
+        run_result?;
+        session_stop_result?;
+        return Ok(());
+    }
+
+    let Some(trace) = record_recovery::load().map_err(CliError::Local)? else {
+        return Err(CliError::Local(anyhow::anyhow!(
+            "no recording in progress; run `bsk record start` first"
+        )));
+    };
+
+    let exported = export_with_recovery(&args.output, &trace)?;
+    render_finish(&trace, &args.output, &exported, format)
+}
+
+/// When `record start` omitted `--url` and the default example.com page
+/// never loaded, rewrite the RPC error so the CLI hint points at `--url`.
+fn annotate_default_start_page_error(err: CliError, user_url: Option<&str>) -> CliError {
+    if user_url.is_some() {
+        return err;
+    }
+    let CliError::Rpc {
+        code,
+        message,
+        data,
+        source,
+    } = err
+    else {
+        return err;
+    };
+    if !is_default_start_page_failure(code, &message) {
+        return CliError::Rpc {
+            code,
+            message,
+            data,
+            source,
+        };
+    }
+    CliError::Rpc {
+        code,
+        message,
+        data: Some(serde_json::json!({
+            "reason": crate::cli::render_error::reason::RECORD_START_PAGE_UNREACHABLE
+        })),
+        source,
+    }
+}
+
+fn is_default_start_page_failure(code: ErrorCode, message: &str) -> bool {
+    match code {
+        ErrorCode::CdpFailed | ErrorCode::Timeout => true,
+        ErrorCode::InvalidParams => {
+            message.contains("restricted URL") || message.contains("about:blank")
+        }
+        _ => false,
+    }
+}
+
+fn prepare_record_start(output: &Path) -> Result<(), CliError> {
+    if record_state::read().is_ok() {
+        return Err(CliError::Local(anyhow::anyhow!(
+            "a recording is already in progress; run `bsk record stop` first"
+        )));
+    }
+    if record_recovery::exists() {
+        return Err(CliError::Local(anyhow::anyhow!(
+            "a previous recording was not exported; run `bsk record stop --output <dir>` to recover it first"
+        )));
+    }
+    validate_record_output(output)
 }
 
 fn record_await_ipc_timeout(timeout_ms: u32) -> Duration {
@@ -190,43 +278,66 @@ fn record_await_ipc_timeout(timeout_ms: u32) -> Duration {
         .unwrap_or(Duration::from_secs(u64::from(timeout_ms / 1_000) + 15))
 }
 
-fn write_trace_file(output: &PathBuf, trace: &RecordedTrace) -> Result<(), CliError> {
-    let json = serde_json::to_string_pretty(trace)
-        .context("serialize trace JSON")
-        .map_err(CliError::Local)?;
-    if let Some(parent) = output.parent() {
-        if !parent.as_os_str().is_empty() {
-            fs::create_dir_all(parent)
-                .with_context(|| format!("create output directory {}", parent.display()))
-                .map_err(CliError::Local)?;
-        }
-    }
-    fs::write(output, format!("{json}\n"))
-        .with_context(|| format!("write trace to {}", output.display()))
-        .map_err(CliError::Local)?;
-    Ok(())
-}
-
-fn render_finish(trace: &RecordedTrace, output: &PathBuf, format: Format) -> Result<(), CliError> {
+fn render_finish(
+    trace: &RecordedTrace,
+    output_dir: &PathBuf,
+    exported: &ExportMeta,
+    format: Format,
+) -> Result<(), CliError> {
+    let trace_path = trace_json_path(output_dir);
     match format {
         Format::Json => {
+            let payload = match trace {
+                RecordedTrace::V3(t) => serde_json::json!({
+                    "output": output_dir,
+                    "trace_json": trace_path,
+                    "trace_version": exported.trace_version,
+                    "states_dir": exported.states_dir,
+                    "trace": t,
+                    "window_closed": true,
+                }),
+                RecordedTrace::V2(t) => serde_json::json!({
+                    "output": output_dir,
+                    "trace_json": trace_path,
+                    "trace_version": exported.trace_version,
+                    "states_dir": null,
+                    "trace": t,
+                    "window_closed": true,
+                }),
+            };
             println!(
                 "{}",
-                serde_json::to_string(&serde_json::json!({
-                    "output": output,
-                    "trace": trace,
-                    "window_closed": true,
-                }))
-                .map_err(|e| CliError::Local(anyhow::anyhow!(e)))?
+                serde_json::to_string(&payload).map_err(|e| CliError::Local(anyhow::anyhow!(e)))?
             );
         }
-        Format::Human => {
-            let step_count = match trace {
-                RecordedTrace::V2(trace) => trace.steps.len(),
-                RecordedTrace::V3(trace) => trace.steps.len(),
-            };
-            println!("saved {step_count} steps to {}", output.display());
-        }
+        Format::Human => match trace {
+            RecordedTrace::V3(t) => {
+                let states_dir = exported
+                    .states_dir
+                    .as_ref()
+                    .map(|p| p.display().to_string())
+                    .unwrap_or_else(|| states_dir_for_output(output_dir).display().to_string());
+                println!(
+                    "saved {} steps to {} and {} states to {}",
+                    t.steps.len(),
+                    trace_path.display(),
+                    t.states.len(),
+                    states_dir
+                );
+            }
+            RecordedTrace::V2(t) => {
+                if exported.v2_fallback {
+                    eprintln!(
+                        "note: extension returned trace v2 (no page observations); update the BrowserSkill extension for v3 bundles"
+                    );
+                }
+                println!(
+                    "saved {} steps to {} (trace v2)",
+                    t.steps.len(),
+                    trace_path.display()
+                );
+            }
+        },
     }
     Ok(())
 }
@@ -234,33 +345,89 @@ fn render_finish(trace: &RecordedTrace, output: &PathBuf, format: Format) -> Res
 fn render_stop(
     result: &RecordStopResult,
     output: &PathBuf,
+    exported: &ExportMeta,
     format: Format,
 ) -> Result<(), CliError> {
-    render_finish(&result.trace, output, format)
+    render_finish(&result.trace, output, exported, format)
 }
 
 #[cfg(test)]
 mod tests {
     use super::*;
 
-    #[test]
-    fn default_output_is_trace_json() {
-        let args = RecordStopArgs {
-            output: PathBuf::from("trace.json"),
-        };
-        assert_eq!(args.output, PathBuf::from("trace.json"));
+    fn with_temp_home<F: FnOnce()>(f: F) {
+        let _lock = record_recovery::test_env_lock();
+        let tmp = tempfile::tempdir().unwrap();
+        unsafe {
+            std::env::set_var(crate::daemon::paths::BSK_HOME_ENV, tmp.path());
+        }
+        f();
+        record_recovery::clear();
+        record_state::clear();
+        unsafe {
+            std::env::remove_var(crate::daemon::paths::BSK_HOME_ENV);
+        }
     }
 
     #[test]
-    fn start_args_default_output_is_trace_json() {
+    fn prepare_record_start_rejects_existing_trace_json_file() {
+        with_temp_home(|| {
+            let dir = tempfile::tempdir().unwrap();
+            let output = dir.path().join("trace.json");
+            std::fs::write(&output, "{}\n").unwrap();
+
+            let err = prepare_record_start(&output).unwrap_err();
+            let msg = err.to_string();
+            assert!(
+                msg.contains("JSON file") || msg.contains("json file"),
+                "{msg}"
+            );
+            assert!(
+                msg.contains("states/") || msg.contains("--output trace"),
+                "{msg}"
+            );
+        });
+    }
+
+    #[test]
+    fn prepare_record_start_rejects_unexported_recovery() {
+        with_temp_home(|| {
+            crate::daemon::paths::ensure_bsk_home().unwrap();
+            std::fs::write(
+                crate::daemon::paths::record_recovery_path().unwrap(),
+                "{}\n",
+            )
+            .unwrap();
+
+            let err = prepare_record_start(Path::new("trace")).unwrap_err();
+            let msg = err.to_string();
+            assert!(
+                msg.contains("not exported") || msg.contains("recover"),
+                "{msg}"
+            );
+        });
+    }
+
+    #[test]
+    fn default_output_is_trace_dir() {
+        let args = RecordStopArgs {
+            output: PathBuf::from("trace"),
+        };
+        assert_eq!(args.output, PathBuf::from("trace"));
+    }
+
+    #[test]
+    fn start_args_default_output_is_trace_dir() {
         let args = RecordStartArgs {
             browser: None,
             tab_id: None,
             url: None,
             purpose: None,
-            output: PathBuf::from("trace.json"),
+            max_page_tokens: None,
+            redact_values: false,
+            output: PathBuf::from("trace"),
         };
-        assert_eq!(args.output, PathBuf::from("trace.json"));
+        assert_eq!(args.output, PathBuf::from("trace"));
     }
 
     #[test]
@@ -268,4 +435,35 @@ mod tests {
         let got = record_await_ipc_timeout(RECORD_AWAIT_TIMEOUT_MS);
         assert!(got >= Duration::from_secs(86_400));
     }
+
+    #[test]
+    fn annotate_default_start_page_error_adds_url_reason() {
+        let err = CliError::from_rpc(bsk_protocol::RpcError {
+            code: ErrorCode::CdpFailed,
+            message: "Page.navigate rejected: net::ERR_ABORTED".into(),
+            data: None,
+        });
+        let annotated = annotate_default_start_page_error(err, None);
+        assert_eq!(
+            crate::cli::render_error::reason_for_data(annotated.data()),
+            Some(crate::cli::render_error::reason::RECORD_START_PAGE_UNREACHABLE)
+        );
+        let info =
+            crate::cli::render_error::info_for_error(annotated.code().unwrap(), annotated.data());
+        assert!(info.hint.unwrap().contains("--url"));
+    }
+
+    #[test]
+    fn annotate_default_start_page_error_skips_when_user_passed_url() {
+        let err = CliError::from_rpc(bsk_protocol::RpcError {
+            code: ErrorCode::CdpFailed,
+            message: "Page.navigate rejected: net::ERR_ABORTED".into(),
+            data: None,
+        });
+        let annotated = annotate_default_start_page_error(err, Some("https://www.example.org/"));
+        assert_eq!(
+            crate::cli::render_error::reason_for_data(annotated.data()),
+            None
+        );
+    }
 }

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

@@ -0,0 +1,976 @@
+use std::collections::HashSet;
+use std::fs::{self, OpenOptions};
+use std::io;
+use std::path::{Path, PathBuf};
+
+use anyhow::Context;
+use bsk_protocol::tools::{RecordedTrace, TRACE_VERSION_V2, TRACE_VERSION_V3, TraceV2, TraceV3};
+use serde::Serialize;
+
+use crate::cli::error::CliError;
+
+#[derive(Debug)]
+pub(super) struct ExportMeta {
+    pub(super) states_dir: Option<PathBuf>,
+    pub(super) trace_version: u32,
+    /// True when the CLI requested v3 but the extension returned legacy v2.
+    pub(super) v2_fallback: bool,
+}
+
+pub(super) fn export_recorded_trace(
+    output_dir: &Path,
+    trace: &RecordedTrace,
+) -> Result<ExportMeta, CliError> {
+    match trace {
+        RecordedTrace::V3(trace) => {
+            let states_dir = write_trace_bundle(output_dir, trace)?;
+            Ok(ExportMeta {
+                states_dir: Some(states_dir),
+                trace_version: TRACE_VERSION_V3,
+                v2_fallback: false,
+            })
+        }
+        RecordedTrace::V2(trace) => {
+            write_trace_v2(output_dir, trace)?;
+            Ok(ExportMeta {
+                states_dir: None,
+                trace_version: TRACE_VERSION_V2,
+                v2_fallback: true,
+            })
+        }
+    }
+}
+
+/// Save the completed Trace first, then write the bundle. Recovery is
+/// removed only after the export commits so a bad `--output` cannot drop
+/// a recording the extension already returned.
+pub(super) fn export_with_recovery(
+    output_dir: &Path,
+    trace: &RecordedTrace,
+) -> Result<ExportMeta, CliError> {
+    let save_result = crate::cli::record_recovery::save(trace);
+    match export_recorded_trace(output_dir, trace) {
+        Ok(meta) => {
+            crate::cli::record_recovery::clear();
+            Ok(meta)
+        }
+        Err(export_err) => {
+            let export_err = annotate_recovery_hint(export_err, save_result.is_ok());
+            if let Err(save_err) = save_result {
+                return Err(match export_err {
+                    CliError::Local(inner) => CliError::Local(
+                        inner.context(format!("also failed to save recovery data: {save_err}")),
+                    ),
+                    other => other,
+                });
+            }
+            Err(export_err)
+        }
+    }
+}
+
+fn annotate_recovery_hint(err: CliError, recovery_saved: bool) -> CliError {
+    if !recovery_saved {
+        return err;
+    }
+    match err {
+        CliError::Local(inner) => CliError::Local(inner.context(
+            "export failed; the recorded trace was saved and can be recovered with `bsk record stop --output <dir>`",
+        )),
+        other => other,
+    }
+}
+
+fn looks_like_json_output(path: &Path) -> bool {
+    path.extension()
+        .and_then(|ext| ext.to_str())
+        .is_some_and(|ext| ext.eq_ignore_ascii_case("json"))
+}
+
+fn legacy_json_output_error(path: &Path) -> CliError {
+    CliError::Local(anyhow::anyhow!(
+        "--output {} is a JSON file path; Trace v3 writes a bundle directory \
+         (`<dir>/trace.json` and `<dir>/states/`), not a single file. \
+         Use `--output trace` or another directory.",
+        path.display()
+    ))
+}
+
+/// Reject legacy `--output trace.json` (and any existing non-directory)
+/// before a recording starts, so the user is not blocked only after Finish.
+pub(super) fn validate_record_output(path: &Path) -> Result<(), CliError> {
+    match fs::symlink_metadata(path) {
+        Ok(metadata) if metadata.file_type().is_symlink() => Err(CliError::Local(anyhow::anyhow!(
+            "--output {} must not be a symlink",
+            path.display()
+        ))),
+        Ok(metadata) if metadata.is_dir() => Ok(()),
+        Ok(_) if looks_like_json_output(path) => Err(legacy_json_output_error(path)),
+        Ok(_) => Err(CliError::Local(anyhow::anyhow!(
+            "--output {} is not a directory; Trace v3 writes a bundle directory \
+             (`<dir>/trace.json` and `<dir>/states/`). Use `--output trace`.",
+            path.display()
+        ))),
+        Err(err) if err.kind() == io::ErrorKind::NotFound => {
+            if looks_like_json_output(path) {
+                Err(legacy_json_output_error(path))
+            } else {
+                Ok(())
+            }
+        }
+        Err(err) => Err(CliError::Local(
+            anyhow::Error::new(err).context(format!("inspect --output {}", path.display())),
+        )),
+    }
+}
+
+fn acquire_export_lock(output_dir: &Path) -> Result<std::fs::File, CliError> {
+    validate_bundle_directory(output_dir, "output bundle directory")?;
+    fs::create_dir_all(output_dir)
+        .with_context(|| format!("create output dir {}", output_dir.display()))
+        .map_err(CliError::Local)?;
+    let lock_path = output_dir.join(".bsk-record-export.lock");
+    let lock_file = OpenOptions::new()
+        .read(true)
+        .write(true)
+        .create(true)
+        .truncate(false)
+        .open(&lock_path)
+        .with_context(|| format!("open export lock {}", lock_path.display()))
+        .map_err(CliError::Local)?;
+    fs2::FileExt::lock_exclusive(&lock_file)
+        .with_context(|| format!("lock export bundle {}", output_dir.display()))
+        .map_err(CliError::Local)?;
+    Ok(lock_file)
+}
+
+pub(super) fn write_trace_v2(output_dir: &Path, trace: &TraceV2) -> Result<(), CliError> {
+    let trace_path = trace_json_path(output_dir);
+    let states_dir = states_dir_for_output(output_dir);
+    let json = serde_json::to_string_pretty(trace)
+        .context("serialize trace JSON")
+        .map_err(CliError::Local)?;
+
+    let _lock = acquire_export_lock(output_dir)?;
+    validate_replaceable_file(&trace_path, "trace JSON")?;
+
+    let transaction_id = uuid::Uuid::new_v4();
+    let staging_dir = output_dir.join(format!(".bsk-record-stage-{transaction_id}"));
+    fs::create_dir_all(&staging_dir)
+        .with_context(|| format!("create staging dir {}", staging_dir.display()))
+        .map_err(CliError::Local)?;
+
+    let staged_trace = staging_dir.join("trace.json");
+    let stage_result: Result<(), CliError> = (|| {
+        fs::write(&staged_trace, format!("{json}\n"))
+            .with_context(|| format!("write staged trace to {}", staged_trace.display()))
+            .map_err(CliError::Local)?;
+        Ok(())
+    })();
+    if let Err(err) = stage_result {
+        let _ = fs::remove_dir_all(&staging_dir);
+        return Err(err);
+    }
+
+    commit_export_transaction(
+        &staging_dir,
+        &states_dir,
+        &HashSet::new(),
+        transaction_id,
+        vec![(
+            staged_trace,
+            trace_path,
+            output_dir.join(format!(".trace.json.{transaction_id}.bak")),
+        )],
+    )?;
+
+    Ok(())
+}
+
+pub(super) fn states_dir_for_output(output_dir: &Path) -> PathBuf {
+    output_dir.join("states")
+}
+
+pub(super) fn trace_json_path(output_dir: &Path) -> PathBuf {
+    output_dir.join("trace.json")
+}
+
+fn is_canonical_state_id(id: &str) -> bool {
+    let Some(number) = id.strip_prefix('s') else {
+        return false;
+    };
+    let mut digits = number.bytes();
+    matches!(digits.next(), Some(b'1'..=b'9')) && digits.all(|byte| byte.is_ascii_digit())
+}
+
+fn validate_bundle_directory(path: &Path, description: &str) -> Result<(), CliError> {
+    match fs::symlink_metadata(path) {
+        Ok(metadata) if metadata.file_type().is_symlink() => Err(CliError::Local(anyhow::anyhow!(
+            "{description} {} must not be a symlink",
+            path.display()
+        ))),
+        Ok(metadata) if metadata.is_dir() => Ok(()),
+        Ok(_) if looks_like_json_output(path) => Err(legacy_json_output_error(path)),
+        Ok(_) => Err(CliError::Local(anyhow::anyhow!(
+            "{description} {} is not a directory; Trace v3 writes `<dir>/trace.json` and `<dir>/states/`. Use `--output trace`.",
+            path.display()
+        ))),
+        Err(err) if err.kind() == io::ErrorKind::NotFound => Ok(()),
+        Err(err) => Err(CliError::Local(
+            anyhow::Error::new(err).context(format!("inspect {description} {}", path.display())),
+        )),
+    }
+}
+
+fn validate_replaceable_file(path: &Path, description: &str) -> Result<(), CliError> {
+    match fs::symlink_metadata(path) {
+        Ok(metadata) if metadata.file_type().is_file() => Ok(()),
+        Ok(_) => Err(CliError::Local(anyhow::anyhow!(
+            "{description} {} is not a regular file",
+            path.display()
+        ))),
+        Err(err) if err.kind() == io::ErrorKind::NotFound => Ok(()),
+        Err(err) => Err(CliError::Local(
+            anyhow::Error::new(err).context(format!("inspect {description} {}", path.display())),
+        )),
+    }
+}
+
+fn commit_staged_file(staged: &Path, target: &Path, backup: &Path) -> io::Result<Option<PathBuf>> {
+    let old_file = match fs::symlink_metadata(target) {
+        Ok(_) => {
+            fs::rename(target, backup)?;
+            Some(backup.to_path_buf())
+        }
+        Err(err) if err.kind() == io::ErrorKind::NotFound => None,
+        Err(err) => return Err(err),
+    };
+
+    if let Err(err) = fs::rename(staged, target) {
+        if let Some(old_file) = old_file.as_deref() {
+            if let Err(restore_err) = fs::rename(old_file, target) {
+                return Err(io::Error::new(
+                    restore_err.kind(),
+                    format!(
+                        "{err}; additionally failed to restore {}: {restore_err}",
+                        target.display()
+                    ),
+                ));
+            }
+        }
+        return Err(err);
+    }
+
+    Ok(old_file)
+}
+
+fn rollback_installed_files(installed: &[(PathBuf, Option<PathBuf>)]) -> io::Result<()> {
+    let mut rollback_error = None;
+    for (target, backup) in installed.iter().rev() {
+        match fs::remove_file(target) {
+            Ok(()) => {}
+            Err(err) if err.kind() == io::ErrorKind::NotFound => {}
+            Err(err) => {
+                rollback_error.get_or_insert(err);
+                continue;
+            }
+        }
+        if let Some(backup) = backup {
+            if let Err(err) = fs::rename(backup, target) {
+                rollback_error.get_or_insert(err);
+            }
+        }
+    }
+    match rollback_error {
+        Some(err) => Err(err),
+        None => Ok(()),
+    }
+}
+
+fn is_generated_state_name(name: &str) -> bool {
+    name.strip_suffix(".txt").is_some_and(is_canonical_state_id)
+}
+
+fn restore_staged_stale_states(staged: &[(PathBuf, PathBuf)]) -> io::Result<()> {
+    let mut restore_error = None;
+    for (original, backup) in staged.iter().rev() {
+        if let Err(err) = fs::rename(backup, original) {
+            restore_error.get_or_insert(err);
+        }
+    }
+    match restore_error {
+        Some(err) => Err(err),
+        None => Ok(()),
+    }
+}
+
+/// Move stale generated states aside so replacement and cleanup form one
+/// rollback boundary. User-owned files, including arbitrary non-`sN.txt`, stay.
+fn stage_stale_states(
+    states_dir: &Path,
+    keep: &HashSet<String>,
+    transaction_id: uuid::Uuid,
+) -> Result<Vec<(PathBuf, PathBuf)>, CliError> {
+    let entries = match fs::read_dir(states_dir) {
+        Ok(entries) => entries,
+        Err(err) if err.kind() == io::ErrorKind::NotFound => return Ok(Vec::new()),
+        Err(err) => {
+            return Err(CliError::Local(
+                anyhow::Error::new(err)
+                    .context(format!("read states dir {}", states_dir.display())),
+            ));
+        }
+    };
+
+    let mut staged = Vec::new();
+    for entry in entries {
+        let entry = match entry {
+            Ok(entry) => entry,
+            Err(err) => {
+                let restore_result = restore_staged_stale_states(&staged);
+                let message = match restore_result {
+                    Ok(()) => format!("read stale state entry: {err}"),
+                    Err(restore_err) => {
+                        format!("read stale state entry: {err}; restore also failed: {restore_err}")
+                    }
+                };
+                return Err(CliError::Local(anyhow::anyhow!(message)));
+            }
+        };
+        let name = entry.file_name();
+        let Some(name) = name.to_str() else { continue };
+        if !is_generated_state_name(name) || keep.contains(name) {
+            continue;
+        }
+
+        let original = entry.path();
+        let file_type = match entry.file_type() {
+            Ok(file_type) => file_type,
+            Err(err) => {
+                let restore_result = restore_staged_stale_states(&staged);
+                let message = match restore_result {
+                    Ok(()) => format!("inspect stale state {}: {err}", original.display()),
+                    Err(restore_err) => format!(
+                        "inspect stale state {}: {err}; restore also failed: {restore_err}",
+                        original.display()
+                    ),
+                };
+                return Err(CliError::Local(anyhow::anyhow!(message)));
+            }
+        };
+        if file_type.is_dir() {
+            let restore_result = restore_staged_stale_states(&staged);
+            let message = match restore_result {
+                Ok(()) => format!("stale state {} is a directory", original.display()),
+                Err(restore_err) => format!(
+                    "stale state {} is a directory; restore also failed: {restore_err}",
+                    original.display()
+                ),
+            };
+            return Err(CliError::Local(anyhow::anyhow!(message)));
+        }
+
+        let backup = states_dir.join(format!(".{name}.{transaction_id}.stale"));
+        if let Err(err) = fs::rename(&original, &backup) {
+            let restore_result = restore_staged_stale_states(&staged);
+            let message = match restore_result {
+                Ok(()) => format!("stage stale state {}: {err}", original.display()),
+                Err(restore_err) => format!(
+                    "stage stale state {}: {err}; restore also failed: {restore_err}",
+                    original.display()
+                ),
+            };
+            return Err(CliError::Local(anyhow::anyhow!(message)));
+        }
+        staged.push((original, backup));
+    }
+    Ok(staged)
+}
+
+fn commit_export_transaction(
+    staging_dir: &Path,
+    states_dir: &Path,
+    keep_states: &HashSet<String>,
+    transaction_id: uuid::Uuid,
+    replacements: Vec<(PathBuf, PathBuf, PathBuf)>,
+) -> Result<(), CliError> {
+    let mut installed = Vec::with_capacity(replacements.len());
+    for (staged, target, backup) in replacements {
+        match commit_staged_file(&staged, &target, &backup) {
+            Ok(old_file) => installed.push((target, old_file)),
+            Err(err) => {
+                let rollback_result = rollback_installed_files(&installed);
+                let _ = fs::remove_dir_all(staging_dir);
+                let message = match rollback_result {
+                    Ok(()) => format!("commit replacement {}: {err}", target.display()),
+                    Err(rollback_err) => format!(
+                        "commit replacement {}: {err}; rollback also failed: {rollback_err}",
+                        target.display()
+                    ),
+                };
+                return Err(CliError::Local(anyhow::anyhow!(message)));
+            }
+        }
+    }
+
+    let stale_states = match stage_stale_states(states_dir, keep_states, transaction_id) {
+        Ok(stale) => stale,
+        Err(err) => {
+            let rollback_result = rollback_installed_files(&installed);
+            let _ = fs::remove_dir_all(staging_dir);
+            let message = match rollback_result {
+                Ok(()) => err.to_string(),
+                Err(rollback_err) => {
+                    format!("{err}; replacement rollback also failed: {rollback_err}")
+                }
+            };
+            return Err(CliError::Local(anyhow::anyhow!(message)));
+        }
+    };
+
+    for (_, backup) in &installed {
+        if let Some(backup) = backup {
+            let _ = fs::remove_file(backup);
+        }
+    }
+    for (_, backup) in stale_states {
+        let _ = fs::remove_file(backup);
+    }
+    let _ = fs::remove_dir_all(staging_dir);
+    Ok(())
+}
+
+#[derive(Serialize)]
+struct BundleState<'a> {
+    id: &'a str,
+    url: &'a str,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    title: Option<&'a str>,
+    page: String,
+    #[serde(skip_serializing_if = "std::ops::Not::not")]
+    truncated: bool,
+}
+
+#[derive(Serialize)]
+struct BundleTrace<'a> {
+    version: u32,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    purpose: Option<&'a str>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    started_at: Option<&'a str>,
+    recorded_at: &'a str,
+    stopped_by: &'a bsk_protocol::tools::StopReason,
+    entry: &'a bsk_protocol::tools::TraceEntry,
+    recorder: &'a bsk_protocol::tools::RecorderInfo,
+    states: Vec<BundleState<'a>>,
+    steps: &'a [bsk_protocol::tools::StepV3],
+}
+
+pub(super) fn write_trace_bundle(output_dir: &Path, trace: &TraceV3) -> Result<PathBuf, CliError> {
+    let states_dir = states_dir_for_output(output_dir);
+    let trace_path = trace_json_path(output_dir);
+
+    if trace.version != TRACE_VERSION_V3 {
+        return Err(CliError::Local(anyhow::anyhow!(
+            "trace version {} is not supported (expected {})",
+            trace.version,
+            TRACE_VERSION_V3
+        )));
+    }
+
+    let mut state_ids = HashSet::with_capacity(trace.states.len());
+    for state in &trace.states {
+        if !is_canonical_state_id(&state.id) {
+            return Err(CliError::Local(anyhow::anyhow!(
+                "state id {:?} is not canonical (expected s1, s2, ...)",
+                state.id
+            )));
+        }
+        if !state_ids.insert(state.id.as_str()) {
+            return Err(CliError::Local(anyhow::anyhow!(
+                "duplicate state id {:?}",
+                state.id
+            )));
+        }
+    }
+
+    let mut disk_states = Vec::with_capacity(trace.states.len());
+    let mut state_writes = Vec::new();
+    let mut keep = HashSet::new();
+    for state in &trace.states {
+        let filename = format!("{}.txt", state.id);
+        let state_path = states_dir.join(&filename);
+        if state_path.parent() != Some(states_dir.as_path()) {
+            return Err(CliError::Local(anyhow::anyhow!(
+                "state path {} escapes states directory {}",
+                state_path.display(),
+                states_dir.display()
+            )));
+        }
+        keep.insert(filename.clone());
+        state_writes.push((filename.clone(), state.body.as_str()));
+        disk_states.push(BundleState {
+            id: &state.id,
+            url: &state.url,
+            title: state.title.as_deref(),
+            page: filename,
+            truncated: state.truncated,
+        });
+    }
+
+    let disk_trace = BundleTrace {
+        version: trace.version,
+        purpose: trace.purpose.as_deref(),
+        started_at: trace.started_at.as_deref(),
+        recorded_at: &trace.recorded_at,
+        stopped_by: &trace.stopped_by,
+        entry: &trace.entry,
+        recorder: &trace.recorder,
+        states: disk_states,
+        steps: &trace.steps,
+    };
+    let json = serde_json::to_string_pretty(&disk_trace)
+        .context("serialize trace JSON")
+        .map_err(CliError::Local)?;
+
+    validate_bundle_directory(output_dir, "output bundle directory")?;
+    fs::create_dir_all(output_dir)
+        .with_context(|| format!("create output dir {}", output_dir.display()))
+        .map_err(CliError::Local)?;
+
+    validate_bundle_directory(&states_dir, "states directory")?;
+
+    let _lock = acquire_export_lock(output_dir)?;
+
+    fs::create_dir_all(&states_dir)
+        .with_context(|| format!("create states dir {}", states_dir.display()))
+        .map_err(CliError::Local)?;
+
+    for (filename, _) in &state_writes {
+        validate_replaceable_file(&states_dir.join(filename), "state observation")?;
+    }
+    validate_replaceable_file(&trace_path, "trace JSON")?;
+
+    let transaction_id = uuid::Uuid::new_v4();
+    let staging_dir = output_dir.join(format!(".bsk-record-stage-{transaction_id}"));
+    let staging_states = staging_dir.join("states");
+    fs::create_dir_all(&staging_states)
+        .with_context(|| format!("create staging dir {}", staging_states.display()))
+        .map_err(CliError::Local)?;
+
+    let stage_result: Result<(), CliError> = (|| {
+        for (filename, body) in &state_writes {
+            let staged_path = staging_states.join(filename);
+            fs::write(&staged_path, body)
+                .with_context(|| {
+                    format!("write staged state observation {}", staged_path.display())
+                })
+                .map_err(CliError::Local)?;
+        }
+        let staged_trace = staging_dir.join("trace.json");
+        fs::write(&staged_trace, format!("{json}\n"))
+            .with_context(|| format!("write staged trace to {}", staged_trace.display()))
+            .map_err(CliError::Local)?;
+        Ok(())
+    })();
+    if let Err(err) = stage_result {
+        let _ = fs::remove_dir_all(&staging_dir);
+        return Err(err);
+    }
+
+    let mut replacements: Vec<(PathBuf, PathBuf, PathBuf)> =
+        Vec::with_capacity(state_writes.len() + 1);
+    for (filename, _) in &state_writes {
+        replacements.push((
+            staging_states.join(filename),
+            states_dir.join(filename),
+            states_dir.join(format!(".{filename}.{transaction_id}.bak")),
+        ));
+    }
+    replacements.push((
+        staging_dir.join("trace.json"),
+        trace_path.clone(),
+        output_dir.join(format!(".trace.json.{transaction_id}.bak")),
+    ));
+
+    commit_export_transaction(
+        &staging_dir,
+        &states_dir,
+        &keep,
+        transaction_id,
+        replacements,
+    )?;
+
+    Ok(states_dir)
+}
+
+#[cfg(test)]
+mod tests {
+    use std::fs;
+
+    use super::*;
+    use bsk_protocol::tools::{
+        NavigationCause, PageRefV2 as PageRef, RecorderInfo, StepCommonV3 as StepCommon,
+        StepResultV3 as StepResult, StepV3 as Step, StopReason, TRACE_VERSION_V2, TRACE_VERSION_V3,
+        TraceEntry, TraceStateV3, TraceV2, TraceV3, VOM_FORMAT_VERSION,
+    };
+
+    fn sample_trace(state_id: &str, body: &str) -> TraceV3 {
+        TraceV3 {
+            version: TRACE_VERSION_V3,
+            recorded_at: "2026-08-10T02:12:55.360Z".into(),
+            stopped_by: StopReason::UserFinish,
+            entry: TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            recorder: RecorderInfo {
+                bsk: "0.1.10".into(),
+                vom: VOM_FORMAT_VERSION,
+            },
+            states: vec![TraceStateV3 {
+                id: state_id.into(),
+                url: "https://example.com/".into(),
+                title: Some("Example".into()),
+                body: body.into(),
+                truncated: false,
+            }],
+            steps: vec![Step::Navigate {
+                common: StepCommon {
+                    id: 1,
+                    state: state_id.into(),
+                    result: StepResult {
+                        state: state_id.into(),
+                    },
+                },
+                to: "https://example.com/".into(),
+                cause: NavigationCause::UserTyped,
+            }],
+            purpose: None,
+            started_at: None,
+        }
+    }
+
+    #[test]
+    fn write_trace_bundle_writes_dir_layout() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        let trace = sample_trace("s1", "@vom 1\nL1 page");
+        let states_dir = write_trace_bundle(&output, &trace).unwrap();
+        let trace_path = output.join("trace.json");
+        assert!(trace_path.exists());
+        assert_eq!(states_dir, output.join("states"));
+        assert!(states_dir.join("s1.txt").exists());
+        let disk: serde_json::Value =
+            serde_json::from_str(&fs::read_to_string(&trace_path).unwrap()).unwrap();
+        assert_eq!(disk["states"][0]["page"], "s1.txt");
+        assert!(disk["states"][0].get("body").is_none());
+        assert_eq!(
+            fs::read_to_string(states_dir.join("s1.txt")).unwrap(),
+            "@vom 1\nL1 page"
+        );
+
+        // Re-exporting drops states from the previous run but keeps the
+        // directory in place for the concurrent writer.
+        fs::write(states_dir.join("s9.txt"), "stale").unwrap();
+        fs::write(states_dir.join("notes.md"), "keep me").unwrap();
+        fs::write(states_dir.join("reference.txt"), "user file").unwrap();
+        write_trace_bundle(&output, &trace).unwrap();
+        assert!(!states_dir.join("s9.txt").exists());
+        assert!(states_dir.join("s1.txt").exists());
+        assert!(states_dir.join("notes.md").exists());
+        assert_eq!(
+            fs::read_to_string(states_dir.join("reference.txt")).unwrap(),
+            "user file"
+        );
+    }
+
+    #[test]
+    fn write_trace_bundle_rejects_traversal_state_id() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        let trace = sample_trace("../escaped", "@vom 1\nL1 page");
+
+        let err = write_trace_bundle(&output, &trace).unwrap_err();
+
+        assert!(err.to_string().contains("state id"));
+        assert!(!output.join("escaped.txt").exists());
+        assert!(!output.join("trace.json").exists());
+    }
+
+    #[test]
+    fn write_trace_bundle_rejects_duplicate_state_id() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        let mut trace = sample_trace("s1", "@vom 1\nL1 first");
+        trace.states.push(TraceStateV3 {
+            body: "@vom 1\nL1 duplicate".into(),
+            ..trace.states[0].clone()
+        });
+
+        let err = write_trace_bundle(&output, &trace).unwrap_err();
+
+        assert!(err.to_string().contains("duplicate state id"));
+        assert!(!output.exists());
+    }
+
+    #[test]
+    fn unsupported_version_preserves_existing_bundle() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        write_trace_bundle(&output, &sample_trace("s1", "original")).unwrap();
+        let original_json = fs::read(output.join("trace.json")).unwrap();
+
+        let mut replacement = sample_trace("s2", "replacement");
+        replacement.version += 1;
+        let err = write_trace_bundle(&output, &replacement).unwrap_err();
+
+        assert!(err.to_string().contains("not supported"));
+        assert_eq!(fs::read(output.join("trace.json")).unwrap(), original_json);
+        assert_eq!(
+            fs::read_to_string(output.join("states/s1.txt")).unwrap(),
+            "original"
+        );
+        assert!(!output.join("states/s2.txt").exists());
+    }
+
+    #[test]
+    fn state_replacement_failure_preserves_existing_bundle() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        write_trace_bundle(&output, &sample_trace("s1", "original")).unwrap();
+        let original_json = fs::read(output.join("trace.json")).unwrap();
+        fs::write(output.join("states/notes.md"), "keep me").unwrap();
+        fs::create_dir(output.join("states/s2.txt")).unwrap();
+
+        let err = write_trace_bundle(&output, &sample_trace("s2", "replacement")).unwrap_err();
+
+        assert!(err.to_string().contains("state"));
+        assert_eq!(fs::read(output.join("trace.json")).unwrap(), original_json);
+        assert_eq!(
+            fs::read_to_string(output.join("states/s1.txt")).unwrap(),
+            "original"
+        );
+        assert_eq!(
+            fs::read_to_string(output.join("states/notes.md")).unwrap(),
+            "keep me"
+        );
+    }
+
+    #[test]
+    fn stale_state_cleanup_failure_rolls_back_replacement() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        write_trace_bundle(&output, &sample_trace("s1", "original")).unwrap();
+        let original_json = fs::read(output.join("trace.json")).unwrap();
+        fs::create_dir(output.join("states/s9.txt")).unwrap();
+
+        let err = write_trace_bundle(&output, &sample_trace("s2", "replacement")).unwrap_err();
+
+        assert!(err.to_string().contains("stale state"));
+        assert_eq!(fs::read(output.join("trace.json")).unwrap(), original_json);
+        assert_eq!(
+            fs::read_to_string(output.join("states/s1.txt")).unwrap(),
+            "original"
+        );
+        assert!(!output.join("states/s2.txt").exists());
+        assert!(output.join("states/s9.txt").is_dir());
+    }
+
+    #[cfg(unix)]
+    #[test]
+    fn write_trace_bundle_rejects_symlinked_states_directory() {
+        use std::os::unix::fs::symlink;
+
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        let external_states = dir.path().join("external-states");
+        fs::create_dir_all(&output).unwrap();
+        fs::create_dir_all(&external_states).unwrap();
+        fs::write(external_states.join("s9.txt"), "external").unwrap();
+        symlink(&external_states, output.join("states")).unwrap();
+
+        let err = write_trace_bundle(&output, &sample_trace("s1", "replacement")).unwrap_err();
+
+        assert!(err.to_string().contains("symlink"));
+        assert_eq!(
+            fs::read_to_string(external_states.join("s9.txt")).unwrap(),
+            "external"
+        );
+        assert!(!external_states.join("s1.txt").exists());
+        assert!(!output.join("trace.json").exists());
+    }
+
+    #[cfg(unix)]
+    #[test]
+    fn write_trace_bundle_rejects_symlinked_output_directory() {
+        use std::os::unix::fs::symlink;
+
+        let dir = tempfile::tempdir().unwrap();
+        let external_output = dir.path().join("external-output");
+        let output = dir.path().join("flow");
+        fs::create_dir_all(&external_output).unwrap();
+        fs::write(external_output.join("notes.md"), "external").unwrap();
+        symlink(&external_output, &output).unwrap();
+
+        let err = write_trace_bundle(&output, &sample_trace("s1", "replacement")).unwrap_err();
+
+        assert!(err.to_string().contains("symlink"));
+        assert_eq!(
+            fs::read_to_string(external_output.join("notes.md")).unwrap(),
+            "external"
+        );
+        assert!(!external_output.join("trace.json").exists());
+        assert!(!external_output.join("states").exists());
+    }
+
+    #[test]
+    fn write_trace_v2_writes_single_json_and_prunes_stale_states() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        fs::create_dir_all(output.join("states")).unwrap();
+        fs::write(output.join("states/s1.txt"), "stale").unwrap();
+
+        let trace = TraceV2 {
+            recorded_at: "2026-08-10T02:12:55.360Z".into(),
+            started_at: None,
+            purpose: None,
+            entry: bsk_protocol::tools::TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            pages: vec![PageRef {
+                id: "p1".into(),
+                url: "https://example.com/".into(),
+                title: None,
+            }],
+            steps: vec![],
+        };
+        write_trace_v2(&output, &trace).unwrap();
+        assert!(output.join("trace.json").exists());
+        assert!(!output.join("states/s1.txt").exists());
+    }
+
+    #[test]
+    fn write_trace_v2_stale_cleanup_failure_rolls_back_trace() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        write_trace_bundle(&output, &sample_trace("s1", "original")).unwrap();
+        let original_json = fs::read(output.join("trace.json")).unwrap();
+        fs::create_dir(output.join("states/s9.txt")).unwrap();
+        let trace = TraceV2 {
+            recorded_at: "2026-08-10T02:12:55.360Z".into(),
+            started_at: None,
+            purpose: None,
+            entry: bsk_protocol::tools::TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            pages: vec![],
+            steps: vec![],
+        };
+
+        let err = write_trace_v2(&output, &trace).unwrap_err();
+
+        assert!(err.to_string().contains("stale state"));
+        assert_eq!(fs::read(output.join("trace.json")).unwrap(), original_json);
+        assert_eq!(
+            fs::read_to_string(output.join("states/s1.txt")).unwrap(),
+            "original"
+        );
+        assert!(output.join("states/s9.txt").is_dir());
+    }
+
+    #[test]
+    fn export_recorded_trace_accepts_v2() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("flow");
+        let trace = RecordedTrace::V2(TraceV2 {
+            recorded_at: "2026-08-10T02:12:55.360Z".into(),
+            started_at: None,
+            purpose: None,
+            entry: bsk_protocol::tools::TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            pages: vec![],
+            steps: vec![],
+        });
+        let exported = export_recorded_trace(&output, &trace).unwrap();
+        assert_eq!(exported.trace_version, TRACE_VERSION_V2);
+        assert!(exported.states_dir.is_none());
+        assert!(output.join("trace.json").exists());
+    }
+
+    #[test]
+    fn existing_trace_json_file_is_rejected_with_bundle_usage() {
+        let dir = tempfile::tempdir().unwrap();
+        let output = dir.path().join("trace.json");
+        fs::write(&output, "{}\n").unwrap();
+
+        let err = validate_record_output(&output).unwrap_err();
+        let msg = err.to_string();
+        assert!(
+            msg.contains("JSON file") || msg.contains("json file"),
+            "should name the legacy JSON file usage: {msg}"
+        );
+        assert!(
+            msg.contains("states/") || msg.contains("--output trace"),
+            "should hint at the new bundle directory usage: {msg}"
+        );
+        assert_eq!(fs::read_to_string(&output).unwrap(), "{}\n");
+    }
+
+    #[test]
+    fn missing_trace_json_path_is_rejected_as_legacy_output() {
+        let err = validate_record_output(Path::new("trace.json")).unwrap_err();
+        let msg = err.to_string();
+        assert!(
+            msg.contains("JSON file") || msg.contains("json file"),
+            "{msg}"
+        );
+        assert!(
+            msg.contains("states/") || msg.contains("--output trace"),
+            "{msg}"
+        );
+    }
+
+    #[test]
+    fn export_failure_keeps_recovery_for_retry() {
+        let _lock = crate::cli::record_recovery::test_env_lock();
+        let tmp = tempfile::tempdir().unwrap();
+        unsafe {
+            std::env::set_var(crate::daemon::paths::BSK_HOME_ENV, tmp.path());
+        }
+
+        let dir = tempfile::tempdir().unwrap();
+        let bad_output = dir.path().join("trace.json");
+        fs::write(&bad_output, "{}\n").unwrap();
+        let trace = RecordedTrace::V3(sample_trace("s1", "@vom 1\nL1 page"));
+
+        let err = export_with_recovery(&bad_output, &trace).unwrap_err();
+        let msg = err.to_string();
+        assert!(
+            msg.contains("recover") || msg.contains("record stop"),
+            "export failure should tell the user how to recover: {msg}"
+        );
+        assert!(
+            crate::cli::record_recovery::exists(),
+            "recovery data must survive a failed bundle export"
+        );
+        let recovered = crate::cli::record_recovery::load()
+            .unwrap()
+            .expect("recovery file");
+        assert_eq!(recovered, trace);
+        assert_eq!(fs::read_to_string(&bad_output).unwrap(), "{}\n");
+
+        let good_output = dir.path().join("bundle");
+        export_with_recovery(&good_output, &recovered).unwrap();
+        assert!(good_output.join("trace.json").exists());
+        assert!(good_output.join("states/s1.txt").exists());
+        assert!(
+            !crate::cli::record_recovery::exists(),
+            "successful export must delete recovery data"
+        );
+
+        unsafe {
+            std::env::remove_var(crate::daemon::paths::BSK_HOME_ENV);
+        }
+    }
+}

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

@@ -0,0 +1,112 @@
+//! Persist a completed Trace so a failed bundle export can be retried.
+
+use std::fs;
+
+use anyhow::{Context, Result};
+use bsk_protocol::tools::RecordedTrace;
+
+use crate::daemon::paths;
+
+pub fn save(trace: &RecordedTrace) -> Result<()> {
+    let path = paths::record_recovery_path()?;
+    paths::ensure_bsk_home()?;
+    let json = serde_json::to_string_pretty(trace).context("serialize record recovery")?;
+    let tmp = path.with_extension("tmp");
+    fs::write(&tmp, format!("{json}\n")).with_context(|| format!("write {}", tmp.display()))?;
+    fs::rename(&tmp, &path).with_context(|| format!("commit {}", path.display()))?;
+    Ok(())
+}
+
+pub fn load() -> Result<Option<RecordedTrace>> {
+    let path = paths::record_recovery_path()?;
+    if !path.exists() {
+        return Ok(None);
+    }
+    let raw = fs::read_to_string(&path).with_context(|| format!("read {}", path.display()))?;
+    let trace = serde_json::from_str(&raw).with_context(|| format!("parse {}", path.display()))?;
+    Ok(Some(trace))
+}
+
+pub fn exists() -> bool {
+    paths::record_recovery_path()
+        .map(|path| path.exists())
+        .unwrap_or(false)
+}
+
+pub fn clear() {
+    if let Ok(path) = paths::record_recovery_path() {
+        let _ = fs::remove_file(path);
+    }
+}
+
+#[cfg(test)]
+pub(crate) fn test_env_lock() -> std::sync::MutexGuard<'static, ()> {
+    crate::daemon::paths::test_env_lock()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use bsk_protocol::tools::{
+        RecorderInfo, StopReason, TRACE_VERSION_V3, TraceEntry, TraceStateV3, TraceV3,
+        VOM_FORMAT_VERSION,
+    };
+
+    fn sample_trace() -> RecordedTrace {
+        RecordedTrace::V3(TraceV3 {
+            version: TRACE_VERSION_V3,
+            recorded_at: "2026-08-10T02:12:55.360Z".into(),
+            stopped_by: StopReason::UserFinish,
+            entry: TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            recorder: RecorderInfo {
+                bsk: "0.1.10".into(),
+                vom: VOM_FORMAT_VERSION,
+            },
+            states: vec![TraceStateV3 {
+                id: "s1".into(),
+                url: "https://example.com/".into(),
+                title: Some("Example".into()),
+                body: "@vom 1\nL1 page".into(),
+                truncated: false,
+            }],
+            steps: vec![],
+            purpose: None,
+            started_at: None,
+        })
+    }
+
+    fn with_temp_home<F: FnOnce()>(f: F) {
+        let _lock = test_env_lock();
+        let tmp = tempfile::tempdir().unwrap();
+        unsafe {
+            std::env::set_var(crate::daemon::paths::BSK_HOME_ENV, tmp.path());
+        }
+        f();
+        clear();
+        unsafe {
+            std::env::remove_var(crate::daemon::paths::BSK_HOME_ENV);
+        }
+    }
+
+    #[test]
+    fn save_load_round_trips() {
+        with_temp_home(|| {
+            let trace = sample_trace();
+            save(&trace).unwrap();
+            assert!(exists());
+            assert_eq!(load().unwrap(), Some(trace));
+        });
+    }
+
+    #[test]
+    fn clear_removes_recovery_file() {
+        with_temp_home(|| {
+            save(&sample_trace()).unwrap();
+            clear();
+            assert!(!exists());
+            assert_eq!(load().unwrap(), None);
+        });
+    }
+}

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

@@ -59,15 +59,9 @@ fn started_at_unix_ms() -> String {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use std::sync::Mutex;
-
-    fn env_guard() -> &'static Mutex<()> {
-        static GUARD: Mutex<()> = Mutex::new(());
-        &GUARD
-    }
 
     fn with_temp_home<F: FnOnce()>(f: F) {
-        let _lock = env_guard().lock().unwrap_or_else(|e| e.into_inner());
+        let _lock = crate::daemon::paths::test_env_lock();
         let tmp = tempfile::tempdir().unwrap();
         unsafe {
             std::env::set_var(crate::daemon::paths::BSK_HOME_ENV, tmp.path());

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

@@ -50,6 +50,7 @@ pub mod reason {
     pub const BORROW_CONFLICT: &str = "borrow_conflict";
     pub const SCREENSHOT_CAPTURE_FAILED: &str = "screenshot_capture_failed";
     pub const SESSION_BUSY: &str = crate::rpc_reason::SESSION_BUSY;
+    pub const RECORD_START_PAGE_UNREACHABLE: &str = "record_start_page_unreachable";
 }
 
 /// Per-code rendering metadata. The `summary` is what the CLI prints
@@ -269,6 +270,16 @@ pub fn info_for_error(code: ErrorCode, data: Option<&serde_json::Value>) -> Rend
             ),
             exit_code: base.exit_code,
         },
+        (
+            ErrorCode::CdpFailed | ErrorCode::Timeout | ErrorCode::InvalidParams,
+            reason::RECORD_START_PAGE_UNREACHABLE,
+        ) => RenderInfo {
+            summary: "default start page https://example.com/ could not be opened",
+            hint: Some(
+                "that site may be unreachable from your network. Pass --url with a page you can open, e.g. `bsk record start --url https://<site>/`",
+            ),
+            exit_code: base.exit_code,
+        },
         _ => base,
     }
 }
@@ -378,6 +389,22 @@ mod tests {
         assert_eq!(info.exit_code, 4);
     }
 
+    #[test]
+    fn record_start_page_unreachable_overrides_cdp_failed_copy() {
+        let data = serde_json::json!({ "reason": reason::RECORD_START_PAGE_UNREACHABLE });
+        let info = info_for_error(ErrorCode::CdpFailed, Some(&data));
+        assert_eq!(
+            info.summary,
+            "default start page https://example.com/ could not be opened"
+        );
+        assert!(
+            info.hint.unwrap().contains("--url"),
+            "expected --url hint, got {:?}",
+            info.hint
+        );
+        assert_eq!(info.exit_code, 3);
+    }
+
     #[test]
     fn screenshot_capture_failed_overrides_cdp_failed_copy() {
         let data = serde_json::json!({ "reason": reason::SCREENSHOT_CAPTURE_FAILED });

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

@@ -100,6 +100,14 @@ pub fn record_session_path() -> Result<PathBuf> {
     Ok(bsk_home()?.join("record-session.json"))
 }
 
+/// Path to a completed Trace saved before bundle export (`record-recovery.json`).
+///
+/// Kept until export succeeds so a failed `--output` write cannot drop the
+/// recording the extension already returned.
+pub fn record_recovery_path() -> Result<PathBuf> {
+    Ok(bsk_home()?.join("record-recovery.json"))
+}
+
 /// Windows named-pipe name. Include the resolved `BSK_HOME` path in the
 /// token so test homes and custom installs do not share a predictable
 /// per-username pipe.
@@ -119,6 +127,13 @@ pub fn pipe_name() -> String {
     render_pipe_name(&user, &home)
 }
 
+/// Process-wide lock for tests that mutate `BSK_HOME`.
+#[cfg(test)]
+pub(crate) fn test_env_lock() -> std::sync::MutexGuard<'static, ()> {
+    static GUARD: std::sync::Mutex<()> = std::sync::Mutex::new(());
+    GUARD.lock().unwrap_or_else(|e| e.into_inner())
+}
+
 /// Render the Windows named-pipe name for a user/home pair. Kept
 /// platform-agnostic so unit tests on any host can pin the output
 /// character set.
@@ -136,19 +151,12 @@ fn render_pipe_name(user: &str, home: &str) -> String {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use std::sync::Mutex;
     use tempfile::TempDir;
 
-    /// Serialise tests that mutate the global `BSK_HOME` env var.
-    fn env_guard() -> &'static Mutex<()> {
-        static GUARD: Mutex<()> = Mutex::new(());
-        &GUARD
-    }
-
     fn with_temp_home<F: FnOnce(&Path)>(f: F) {
-        let _lock = env_guard().lock().unwrap_or_else(|e| e.into_inner());
+        let _lock = test_env_lock();
         let tmp = TempDir::new().unwrap();
-        // SAFETY: serialised by env_guard above.
+        // SAFETY: serialised by test_env_lock above.
         unsafe {
             std::env::set_var(BSK_HOME_ENV, tmp.path().join("bsk"));
         }
@@ -187,6 +195,10 @@ mod tests {
                 record_session_path().unwrap(),
                 home.join("record-session.json")
             );
+            assert_eq!(
+                record_recovery_path().unwrap(),
+                home.join("record-recovery.json")
+            );
         });
     }
 

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

@@ -26,7 +26,7 @@ use crate::daemon::{
     browsers::{BROWSER_LIVENESS_TICK, BROWSER_LIVENESS_TIMEOUT, EXTENSION_CONNECT_WAIT},
     info as daemon_info, ipc, lockfile, paths,
     sessions::{StopSessionError, forget_session, stop_session},
-    state::DaemonState,
+    state::{DaemonState, PROTOCOL_VERSION},
     ws,
 };
 
@@ -297,7 +297,7 @@ pub fn run_foreground(cfg: DaemonConfig) -> Result<()> {
             ws_port,
             sock_path: sock_path.clone(),
             daemon_version: env!("CARGO_PKG_VERSION"),
-            protocol_version: "1.0",
+            protocol_version: PROTOCOL_VERSION,
         };
         let handler = ipc::full_handler(status, Arc::clone(&state));
 

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

@@ -16,7 +16,7 @@ use super::start::DaemonConfig;
 use super::ws::WsHandle;
 
 pub const DAEMON_VERSION: &str = env!("CARGO_PKG_VERSION");
-pub const PROTOCOL_VERSION: &str = "1.0";
+pub const PROTOCOL_VERSION: &str = "1.1";
 /// Lowest **protocol** version peers must speak (e.g. `"1.0"`).
 pub const MIN_COMPATIBLE_PROTOCOL: &str = "1.0";
 /// Legacy app-semver floor used only when `HandshakeResult.min_compatible_peer`

crates/bsk-cli/tests/handshake_compat.rs

@@ -108,12 +108,12 @@ async fn send_handshake_with_floors(
 async fn handshake_ok_when_protocol_matches() {
     let (handle, _sock) = spawn_daemon().await;
     let mut ws = open_ws(handle.ws_addr()).await;
-    let resp = send_handshake(&mut ws, "1.0", env!("CARGO_PKG_VERSION")).await;
+    let resp = send_handshake(&mut ws, "1.1", env!("CARGO_PKG_VERSION")).await;
     let result: HandshakeResult = match resp.body {
         ResponseBody::Ok(v) => serde_json::from_value(v).unwrap(),
         ResponseBody::Err(e) => panic!("expected ok handshake, got {e:?}"),
     };
-    assert_eq!(result.protocol_version, "1.0");
+    assert_eq!(result.protocol_version, "1.1");
     assert_eq!(
         result
             .min_compatible_peer
@@ -135,7 +135,7 @@ async fn handshake_ok_when_app_versions_differ_but_protocol_matches() {
     let (handle, _sock) = spawn_daemon().await;
     let mut ws = open_ws(handle.ws_addr()).await;
     let resp =
-        send_handshake_with_floors(&mut ws, "1.0", "9.9.9", Some("0.0.0"), Some("1.0")).await;
+        send_handshake_with_floors(&mut ws, "1.1", "9.9.9", Some("0.0.0"), Some("1.1")).await;
     match resp.body {
         ResponseBody::Ok(_) => {}
         other => panic!("expected ok when protocol matches, got {other:?}"),
@@ -149,10 +149,10 @@ async fn handshake_skew_when_protocol_minor_differs() {
     let mut ws = open_ws(handle.ws_addr()).await;
     let resp = send_handshake_with_floors(
         &mut ws,
-        "1.1",
+        "1.2",
         env!("CARGO_PKG_VERSION"),
         Some("0.0.0"),
-        Some("1.0"),
+        Some("1.1"),
     )
     .await;
     match resp.body {
@@ -210,7 +210,7 @@ async fn handshake_legacy_ext_without_protocol_floor_still_ok() {
     let mut ws = open_ws(handle.ws_addr()).await;
     let resp = send_handshake_with_floors(
         &mut ws,
-        "1.0",
+        "1.1",
         env!("CARGO_PKG_VERSION"),
         Some("0.1.0"),
         None,
@@ -235,7 +235,7 @@ async fn status_surfaces_version_skew_for_skewed_browser() {
         browser_name: "chrome".into(),
         browser_version: "131.0".into(),
         extension_version: "9.9.9".into(),
-        extension_protocol_version: "1.1".into(),
+        extension_protocol_version: "1.2".into(),
         label: "Older".into(),
         sink: bsk::daemon::browsers::BrowserSink { tx },
         pending: Mutex::new(bsk::daemon::browsers::Pending::default()),
@@ -263,8 +263,8 @@ async fn status_surfaces_version_skew_for_skewed_browser() {
         .iter()
         .find(|s| s.instance_id == "skew-only-test")
         .expect("status must list our skew client");
-    assert_eq!(skew.client_protocol_version, "1.1");
-    assert_eq!(skew.server_protocol_version, "1.0");
+    assert_eq!(skew.client_protocol_version, "1.2");
+    assert_eq!(skew.server_protocol_version, "1.1");
     assert_eq!(skew.client_version, "9.9.9");
     let entry = status
         .browsers
@@ -281,7 +281,7 @@ async fn handshake_rejects_when_local_below_peer_min_compatible_protocol() {
     let mut ws = open_ws(handle.ws_addr()).await;
     let resp = send_handshake_with_floors(
         &mut ws,
-        "1.0",
+        "1.1",
         env!("CARGO_PKG_VERSION"),
         Some("0.0.0"),
         Some("99.0.0"),

crates/bsk-cli/tests/record_export_recovery.rs

@@ -0,0 +1,327 @@
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::time::Duration;
+
+use bsk::daemon::info::DaemonInfo;
+use bsk::daemon::paths::BSK_HOME_ENV;
+use bsk::daemon::{self, DaemonConfig};
+use bsk::ipc_client::IpcClient;
+use bsk_protocol::system::{HandshakeParams, HandshakeResult};
+use bsk_protocol::tools::{
+    RecordStopResult, RecordedTrace, RecorderInfo, SessionStartParams, SessionStartResult,
+    StopReason, TraceEntry, TraceStateV3, TraceV3, VOM_FORMAT_VERSION,
+};
+use bsk_protocol::{BrowserPeerInfo, Frame, Method, RequestFrame, ResponseBody, ResponseFrame};
+use futures_util::{SinkExt, StreamExt};
+use serde_json::json;
+use tokio::process::Command;
+use tokio_tungstenite::tungstenite::handshake::client::generate_key;
+use tokio_tungstenite::tungstenite::http::Request;
+use tokio_tungstenite::tungstenite::protocol::Message;
+
+const TEST_EXT_ID: &str = "abcdefghijklmnopabcdefghijklmnop";
+
+type Ws =
+    tokio_tungstenite::WebSocketStream<tokio_tungstenite::MaybeTlsStream<tokio::net::TcpStream>>;
+
+fn bsk_bin() -> PathBuf {
+    PathBuf::from(env!("CARGO_BIN_EXE_bsk"))
+}
+
+async fn connect_extension(addr: std::net::SocketAddr) -> Ws {
+    let origin = format!("chrome-extension://{TEST_EXT_ID}");
+    let request = Request::builder()
+        .method("GET")
+        .uri(format!("ws://{addr}/"))
+        .header("Host", addr.to_string())
+        .header("Upgrade", "websocket")
+        .header("Connection", "Upgrade")
+        .header("Sec-WebSocket-Version", "13")
+        .header("Sec-WebSocket-Key", generate_key())
+        .header("Origin", origin)
+        .body(())
+        .unwrap();
+    tokio_tungstenite::connect_async(request).await.unwrap().0
+}
+
+async fn handshake(ws: &mut Ws) {
+    let request = RequestFrame {
+        id: "handshake".into(),
+        method: Method::SystemHandshake,
+        params: Some(
+            serde_json::to_value(HandshakeParams {
+                client: "browser-skill-extension".into(),
+                version: "0.1.10".parse().unwrap(),
+                protocol_version: "1.1".into(),
+                instance_id: TEST_EXT_ID.into(),
+                browser: BrowserPeerInfo {
+                    name: "chrome".into(),
+                    version: "131.0".into(),
+                },
+                min_compatible_peer: Some("0.1.10".parse().unwrap()),
+                min_compatible_protocol: Some("1.1".into()),
+                label: "Record export recovery test".into(),
+            })
+            .unwrap(),
+        ),
+    };
+    ws.send(Message::Text(serde_json::to_string(&request).unwrap()))
+        .await
+        .unwrap();
+    let Message::Text(response) = ws.next().await.unwrap().unwrap() else {
+        panic!("expected text handshake response");
+    };
+    let response: ResponseFrame = serde_json::from_str(&response).unwrap();
+    let ResponseBody::Ok(value) = response.body else {
+        panic!("handshake failed");
+    };
+    let _: HandshakeResult = serde_json::from_value(value).unwrap();
+}
+
+fn sample_trace() -> TraceV3 {
+    TraceV3 {
+        version: 3,
+        purpose: Some("export recovery".into()),
+        started_at: Some("2026-08-12T10:00:00Z".into()),
+        recorded_at: "2026-08-12T10:01:00Z".into(),
+        stopped_by: StopReason::CliStop,
+        entry: TraceEntry {
+            start_url: "https://example.com/".into(),
+        },
+        recorder: RecorderInfo {
+            bsk: "0.1.10".into(),
+            vom: VOM_FORMAT_VERSION,
+        },
+        states: vec![TraceStateV3 {
+            id: "s1".into(),
+            url: "https://example.com/".into(),
+            title: Some("Example".into()),
+            body: "@vom 1\nL1 page".into(),
+            truncated: false,
+        }],
+        steps: vec![],
+    }
+}
+
+fn run_extension(
+    mut ws: Ws,
+    record_stop_calls: Arc<AtomicUsize>,
+    session_stop_calls: Arc<AtomicUsize>,
+) {
+    tokio::spawn(async move {
+        while let Some(Ok(Message::Text(text))) = ws.next().await {
+            let Ok(Frame::Request(request)) = serde_json::from_str::<Frame>(&text) else {
+                continue;
+            };
+            let body = match request.method {
+                Method::ToolSessionStart => {
+                    let _: SessionStartParams =
+                        serde_json::from_value(request.params.clone().unwrap()).unwrap();
+                    ResponseBody::Ok(
+                        serde_json::to_value(SessionStartResult {
+                            agent_window_id: Some(100),
+                        })
+                        .unwrap(),
+                    )
+                }
+                Method::ToolRecordStop => {
+                    record_stop_calls.fetch_add(1, Ordering::SeqCst);
+                    ResponseBody::Ok(
+                        serde_json::to_value(RecordStopResult {
+                            trace: RecordedTrace::V3(sample_trace()),
+                        })
+                        .unwrap(),
+                    )
+                }
+                Method::ToolSessionStop => {
+                    session_stop_calls.fetch_add(1, Ordering::SeqCst);
+                    ResponseBody::Ok(json!({}))
+                }
+                _ => ResponseBody::Err(bsk_protocol::RpcError {
+                    code: bsk_protocol::ErrorCode::ProtocolError,
+                    message: format!("unexpected method {:?}", request.method),
+                    data: None,
+                }),
+            };
+            let response = ResponseFrame {
+                id: request.id,
+                body,
+            };
+            ws.send(Message::Text(serde_json::to_string(&response).unwrap()))
+                .await
+                .unwrap();
+        }
+    });
+}
+
+async fn start_session(sock: &Path) -> String {
+    #[derive(serde::Deserialize)]
+    struct StartResult {
+        session_id: String,
+    }
+
+    let mut client = IpcClient::connect(sock).await.unwrap();
+    client
+        .call::<(), StartResult>(
+            "session-start",
+            Method::SessionStart,
+            None,
+            Duration::from_secs(5),
+        )
+        .await
+        .unwrap()
+        .unwrap()
+        .session_id
+}
+
+fn write_record_session(home: &Path, session_id: &str) {
+    std::fs::create_dir_all(home).unwrap();
+    std::fs::write(
+        home.join("record-session.json"),
+        format!("{{\"session_id\":\"{session_id}\",\"started_at\":\"1\"}}\n"),
+    )
+    .unwrap();
+}
+
+async fn run_record_stop(home: &Path, output: &Path) -> std::process::Output {
+    Command::new(bsk_bin())
+        .arg("record")
+        .arg("stop")
+        .arg("--output")
+        .arg(output)
+        .env(BSK_HOME_ENV, home)
+        .output()
+        .await
+        .unwrap()
+}
+
+async fn setup_daemon(temp: &Path) -> (bsk::daemon::DaemonHandle, PathBuf, PathBuf) {
+    let home = temp.join("bsk-home");
+    let sock = temp.join("daemon.sock");
+    let daemon = daemon::run(DaemonConfig::new(0), Some(sock.clone()))
+        .await
+        .unwrap();
+    bsk::daemon::info::write_to_path(
+        &DaemonInfo::now(
+            std::process::id(),
+            sock.clone(),
+            daemon.ws_addr().port(),
+            env!("CARGO_PKG_VERSION"),
+        ),
+        &home.join("daemon.json"),
+    )
+    .unwrap();
+    (daemon, home, sock)
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn existing_trace_json_file_is_rejected_before_record_stop() {
+    let temp = tempfile::Builder::new()
+        .prefix("bsk-record-json-")
+        .tempdir()
+        .unwrap();
+    let (daemon, home, sock) = setup_daemon(temp.path()).await;
+    let output = temp.path().join("trace.json");
+    std::fs::write(&output, "{}\n").unwrap();
+
+    let mut extension = connect_extension(daemon.ws_addr()).await;
+    handshake(&mut extension).await;
+    let record_stop_calls = Arc::new(AtomicUsize::new(0));
+    let session_stop_calls = Arc::new(AtomicUsize::new(0));
+    run_extension(
+        extension,
+        Arc::clone(&record_stop_calls),
+        Arc::clone(&session_stop_calls),
+    );
+
+    let session_id = start_session(&sock).await;
+    write_record_session(&home, &session_id);
+
+    let first = run_record_stop(&home, &output).await;
+    let stderr = String::from_utf8_lossy(&first.stderr);
+    assert!(
+        !first.status.success(),
+        "legacy JSON --output should fail: {stderr}"
+    );
+    assert!(
+        stderr.contains("JSON file") || stderr.contains("bundle directory"),
+        "{stderr}"
+    );
+    let state: serde_json::Value =
+        serde_json::from_str(&std::fs::read_to_string(home.join("record-session.json")).unwrap())
+            .unwrap();
+    assert_eq!(state["session_id"], session_id);
+    assert_eq!(
+        record_stop_calls.load(Ordering::SeqCst),
+        0,
+        "existing trace.json must be rejected before the extension returns the Trace"
+    );
+    assert_eq!(session_stop_calls.load(Ordering::SeqCst), 0);
+    assert_eq!(std::fs::read_to_string(&output).unwrap(), "{}\n");
+
+    daemon.shutdown().await;
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn failed_bundle_export_can_be_recovered() {
+    let temp = tempfile::Builder::new()
+        .prefix("bsk-record-recov-")
+        .tempdir()
+        .unwrap();
+    let (daemon, home, sock) = setup_daemon(temp.path()).await;
+    let output = temp.path().join("trace");
+    std::fs::create_dir_all(&output).unwrap();
+    std::fs::write(output.join("states"), "not a directory\n").unwrap();
+
+    let mut extension = connect_extension(daemon.ws_addr()).await;
+    handshake(&mut extension).await;
+    let record_stop_calls = Arc::new(AtomicUsize::new(0));
+    let session_stop_calls = Arc::new(AtomicUsize::new(0));
+    run_extension(
+        extension,
+        Arc::clone(&record_stop_calls),
+        Arc::clone(&session_stop_calls),
+    );
+
+    let session_id = start_session(&sock).await;
+    write_record_session(&home, &session_id);
+
+    let first = run_record_stop(&home, &output).await;
+    let stderr = String::from_utf8_lossy(&first.stderr);
+    assert!(
+        !first.status.success(),
+        "blocked states path should fail export: {stderr}"
+    );
+    assert!(
+        home.join("record-recovery.json").exists(),
+        "completed Trace must be saved before the failed export"
+    );
+    assert!(
+        !home.join("record-session.json").exists(),
+        "session state is cleared after the extension returns the Trace"
+    );
+    assert_eq!(record_stop_calls.load(Ordering::SeqCst), 1);
+    assert_eq!(session_stop_calls.load(Ordering::SeqCst), 1);
+
+    std::fs::remove_file(output.join("states")).unwrap();
+    let second = run_record_stop(&home, &output).await;
+    assert!(
+        second.status.success(),
+        "recovery export failed: {}",
+        String::from_utf8_lossy(&second.stderr)
+    );
+    assert_eq!(
+        record_stop_calls.load(Ordering::SeqCst),
+        1,
+        "recovery must not call the extension again"
+    );
+    assert!(output.join("trace.json").exists());
+    assert!(output.join("states/s1.txt").exists());
+    assert!(
+        !home.join("record-recovery.json").exists(),
+        "successful export must delete recovery data"
+    );
+
+    daemon.shutdown().await;
+}

crates/bsk-cli/tests/record_stop_retry.rs

@@ -0,0 +1,271 @@
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::time::Duration;
+
+use bsk::cli::record_state;
+use bsk::daemon::info::DaemonInfo;
+use bsk::daemon::paths::BSK_HOME_ENV;
+use bsk::daemon::{self, DaemonConfig};
+use bsk::ipc_client::IpcClient;
+use bsk_protocol::system::{HandshakeParams, HandshakeResult};
+use bsk_protocol::tools::{
+    RecordStopResult, RecordedTrace, RecorderInfo, SessionStartParams, SessionStartResult,
+    StopReason, TraceEntry, TraceStateV3, TraceV3, VOM_FORMAT_VERSION,
+};
+use bsk_protocol::{
+    BrowserPeerInfo, ErrorCode, Frame, Method, RequestFrame, ResponseBody, ResponseFrame, RpcError,
+};
+use futures_util::{SinkExt, StreamExt};
+use serde_json::json;
+use tokio::process::Command;
+use tokio_tungstenite::tungstenite::handshake::client::generate_key;
+use tokio_tungstenite::tungstenite::http::Request;
+use tokio_tungstenite::tungstenite::protocol::Message;
+
+const TEST_EXT_ID: &str = "abcdefghijklmnopabcdefghijklmnop";
+
+type Ws =
+    tokio_tungstenite::WebSocketStream<tokio_tungstenite::MaybeTlsStream<tokio::net::TcpStream>>;
+
+fn bsk_bin() -> PathBuf {
+    PathBuf::from(env!("CARGO_BIN_EXE_bsk"))
+}
+
+async fn connect_extension(addr: std::net::SocketAddr) -> Ws {
+    let origin = format!("chrome-extension://{TEST_EXT_ID}");
+    let request = Request::builder()
+        .method("GET")
+        .uri(format!("ws://{addr}/"))
+        .header("Host", addr.to_string())
+        .header("Upgrade", "websocket")
+        .header("Connection", "Upgrade")
+        .header("Sec-WebSocket-Version", "13")
+        .header("Sec-WebSocket-Key", generate_key())
+        .header("Origin", origin)
+        .body(())
+        .unwrap();
+    tokio_tungstenite::connect_async(request).await.unwrap().0
+}
+
+async fn handshake(ws: &mut Ws) {
+    let request = RequestFrame {
+        id: "handshake".into(),
+        method: Method::SystemHandshake,
+        params: Some(
+            serde_json::to_value(HandshakeParams {
+                client: "browser-skill-extension".into(),
+                version: "0.1.10".parse().unwrap(),
+                protocol_version: "1.1".into(),
+                instance_id: TEST_EXT_ID.into(),
+                browser: BrowserPeerInfo {
+                    name: "chrome".into(),
+                    version: "131.0".into(),
+                },
+                min_compatible_peer: Some("0.1.10".parse().unwrap()),
+                min_compatible_protocol: Some("1.1".into()),
+                label: "Record stop retry test".into(),
+            })
+            .unwrap(),
+        ),
+    };
+    ws.send(Message::Text(serde_json::to_string(&request).unwrap()))
+        .await
+        .unwrap();
+    let Message::Text(response) = ws.next().await.unwrap().unwrap() else {
+        panic!("expected text handshake response");
+    };
+    let response: ResponseFrame = serde_json::from_str(&response).unwrap();
+    let ResponseBody::Ok(value) = response.body else {
+        panic!("handshake failed");
+    };
+    let _: HandshakeResult = serde_json::from_value(value).unwrap();
+}
+
+fn sample_trace() -> TraceV3 {
+    TraceV3 {
+        version: 3,
+        purpose: Some("retry record stop".into()),
+        started_at: Some("2026-08-12T10:00:00Z".into()),
+        recorded_at: "2026-08-12T10:01:00Z".into(),
+        stopped_by: StopReason::CliStop,
+        entry: TraceEntry {
+            start_url: "https://example.com/".into(),
+        },
+        recorder: RecorderInfo {
+            bsk: "0.1.10".into(),
+            vom: VOM_FORMAT_VERSION,
+        },
+        states: vec![TraceStateV3 {
+            id: "s1".into(),
+            url: "https://example.com/".into(),
+            title: Some("Example".into()),
+            body: "@vom 1\nL1 page".into(),
+            truncated: false,
+        }],
+        steps: vec![],
+    }
+}
+
+fn run_extension(
+    mut ws: Ws,
+    record_stop_calls: Arc<AtomicUsize>,
+    session_stop_calls: Arc<AtomicUsize>,
+) {
+    tokio::spawn(async move {
+        while let Some(Ok(Message::Text(text))) = ws.next().await {
+            let Ok(Frame::Request(request)) = serde_json::from_str::<Frame>(&text) else {
+                continue;
+            };
+            let body = match request.method {
+                Method::ToolSessionStart => {
+                    let _: SessionStartParams =
+                        serde_json::from_value(request.params.clone().unwrap()).unwrap();
+                    ResponseBody::Ok(
+                        serde_json::to_value(SessionStartResult {
+                            agent_window_id: Some(100),
+                        })
+                        .unwrap(),
+                    )
+                }
+                Method::ToolRecordStop => {
+                    if record_stop_calls.fetch_add(1, Ordering::SeqCst) == 0 {
+                        ResponseBody::Err(RpcError {
+                            code: ErrorCode::ProtocolError,
+                            message: "recording remains active; retry record stop".into(),
+                            data: Some(json!({ "recording": true, "retryable": true })),
+                        })
+                    } else {
+                        ResponseBody::Ok(
+                            serde_json::to_value(RecordStopResult {
+                                trace: RecordedTrace::V3(sample_trace()),
+                            })
+                            .unwrap(),
+                        )
+                    }
+                }
+                Method::ToolSessionStop => {
+                    session_stop_calls.fetch_add(1, Ordering::SeqCst);
+                    ResponseBody::Ok(json!({}))
+                }
+                _ => ResponseBody::Err(RpcError {
+                    code: ErrorCode::ProtocolError,
+                    message: format!("unexpected method {:?}", request.method),
+                    data: None,
+                }),
+            };
+            let response = ResponseFrame {
+                id: request.id,
+                body,
+            };
+            ws.send(Message::Text(serde_json::to_string(&response).unwrap()))
+                .await
+                .unwrap();
+        }
+    });
+}
+
+async fn start_session(sock: &Path) -> String {
+    #[derive(serde::Deserialize)]
+    struct StartResult {
+        session_id: String,
+    }
+
+    let mut client = IpcClient::connect(sock).await.unwrap();
+    client
+        .call::<(), StartResult>(
+            "session-start",
+            Method::SessionStart,
+            None,
+            Duration::from_secs(5),
+        )
+        .await
+        .unwrap()
+        .unwrap()
+        .session_id
+}
+
+async fn run_record_stop(home: &Path, output: &Path) -> std::process::Output {
+    Command::new(bsk_bin())
+        .arg("record")
+        .arg("stop")
+        .arg("--output")
+        .arg(output)
+        .env(BSK_HOME_ENV, home)
+        .output()
+        .await
+        .unwrap()
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn failed_record_stop_keeps_state_and_session_for_retry() {
+    // Keep the Unix-domain socket below macOS's SUN_LEN even from a deep worktree.
+    let temp = tempfile::Builder::new()
+        .prefix("bsk-record-stop-")
+        .tempdir()
+        .unwrap();
+    let home = temp.path().join("bsk-home");
+    let sock = temp.path().join("daemon.sock");
+    let output = temp.path().join("trace");
+
+    let daemon = daemon::run(DaemonConfig::new(0), Some(sock.clone()))
+        .await
+        .unwrap();
+    bsk::daemon::info::write_to_path(
+        &DaemonInfo::now(
+            std::process::id(),
+            sock.clone(),
+            daemon.ws_addr().port(),
+            env!("CARGO_PKG_VERSION"),
+        ),
+        &home.join("daemon.json"),
+    )
+    .unwrap();
+
+    let mut extension = connect_extension(daemon.ws_addr()).await;
+    handshake(&mut extension).await;
+    let record_stop_calls = Arc::new(AtomicUsize::new(0));
+    let session_stop_calls = Arc::new(AtomicUsize::new(0));
+    run_extension(
+        extension,
+        Arc::clone(&record_stop_calls),
+        Arc::clone(&session_stop_calls),
+    );
+
+    let session_id = start_session(&sock).await;
+    unsafe {
+        std::env::set_var(BSK_HOME_ENV, &home);
+    }
+    record_state::write(&session_id).unwrap();
+
+    let first = run_record_stop(&home, &output).await;
+    assert!(
+        !first.status.success(),
+        "first stop unexpectedly succeeded: {}",
+        String::from_utf8_lossy(&first.stdout)
+    );
+    assert_eq!(record_state::read().unwrap().session_id, session_id);
+    assert_eq!(record_stop_calls.load(Ordering::SeqCst), 1);
+    assert_eq!(
+        session_stop_calls.load(Ordering::SeqCst),
+        0,
+        "failed record stop must leave the session active"
+    );
+
+    let second = run_record_stop(&home, &output).await;
+    assert!(
+        second.status.success(),
+        "retry failed: {}",
+        String::from_utf8_lossy(&second.stderr)
+    );
+    assert!(record_state::read().is_err());
+    assert_eq!(record_stop_calls.load(Ordering::SeqCst), 2);
+    assert_eq!(session_stop_calls.load(Ordering::SeqCst), 1);
+    assert!(output.join("trace.json").exists());
+    assert!(output.join("states/s1.txt").exists());
+
+    unsafe {
+        std::env::remove_var(BSK_HOME_ENV);
+    }
+    daemon.shutdown().await;
+}

crates/bsk-cli/tests/status_cmd.rs

@@ -61,7 +61,7 @@ fn bsk_status_json_returns_structured_payload() {
 
     assert!(parsed["pid"].as_u64().unwrap() > 0);
     assert!(!parsed["daemon_version"].as_str().unwrap().is_empty());
-    assert_eq!(parsed["protocol_version"], "1.0");
+    assert_eq!(parsed["protocol_version"], "1.1");
     assert!(parsed["sock_path"].as_str().is_some());
     assert_eq!(parsed["browsers"], serde_json::json!([]));
     assert_eq!(parsed["sessions"], serde_json::json!([]));

crates/bsk-cli/tests/ws_handshake.rs

@@ -53,7 +53,7 @@ pub async fn send_handshake(
     let params = HandshakeParams {
         client: "browser-skill-extension".into(),
         version: "0.1.0-dev.0".parse().unwrap(),
-        protocol_version: "1.0".into(),
+        protocol_version: "1.1".into(),
         instance_id: instance_id.into(),
         browser: BrowserPeerInfo {
             name: "chrome".into(),
@@ -91,7 +91,7 @@ async fn ws_handshake_registers_browser_in_state() {
     let mut ws = connect_ext(handle.ws_addr(), &origin).await;
     let result = send_handshake(&mut ws, TEST_EXT_ID).await;
     assert_eq!(result.server, "browser-skill-daemon");
-    assert_eq!(result.protocol_version, "1.0");
+    assert_eq!(result.protocol_version, "1.1");
 
     let state = handle.state();
     let browsers = state.browsers.snapshot();

crates/bsk-protocol/schema/tool_record_await_result.json

@@ -480,6 +480,36 @@
             }
           }
         },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "switch_tab"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
+        },
         {
           "description": "Fields shared by every step variant (flattened in JSON).",
           "type": "object",

crates/bsk-protocol/schema/tool_record_start_params.json

@@ -6,15 +6,36 @@
     "session_id"
   ],
   "properties": {
+    "max_page_tokens": {
+      "type": [
+        "integer",
+        "null"
+      ],
+      "format": "uint32",
+      "minimum": 0.0
+    },
     "purpose": {
       "type": [
         "string",
         "null"
       ]
     },
+    "redact_values": {
+      "type": [
+        "boolean",
+        "null"
+      ]
+    },
     "session_id": {
       "type": "string"
     },
+    "supports_tab_switch_steps": {
+      "description": "Client can decode the v3 `switch_tab` step variant.",
+      "type": [
+        "boolean",
+        "null"
+      ]
+    },
     "tab_id": {
       "type": [
         "integer",
@@ -22,6 +43,15 @@
       ],
       "format": "int64"
     },
+    "trace_version": {
+      "description": "Desired trace export format. Omitted means v2; `3` requests v3.",
+      "type": [
+        "integer",
+        "null"
+      ],
+      "format": "uint32",
+      "minimum": 0.0
+    },
     "url": {
       "type": [
         "string",

crates/bsk-protocol/schema/tool_record_stop_result.json

@@ -480,6 +480,36 @@
             }
           }
         },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "switch_tab"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
+        },
         {
           "description": "Fields shared by every step variant (flattened in JSON).",
           "type": "object",

crates/bsk-protocol/schema/trace.json

@@ -469,6 +469,36 @@
             }
           }
         },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "switch_tab"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
+        },
         {
           "description": "Fields shared by every step variant (flattened in JSON).",
           "type": "object",

crates/bsk-protocol/schema/trace_step.json

@@ -431,6 +431,36 @@
             }
           }
         },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "switch_tab"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
+        },
         {
           "description": "Fields shared by every step variant (flattened in JSON).",
           "type": "object",

crates/bsk-protocol/schema/trace_step_v3.json

@@ -41,6 +41,36 @@
         }
       }
     },
+    {
+      "description": "Fields shared by every step variant (flattened in JSON).",
+      "type": "object",
+      "required": [
+        "id",
+        "op",
+        "result",
+        "state"
+      ],
+      "properties": {
+        "id": {
+          "type": "integer",
+          "format": "uint32",
+          "minimum": 0.0
+        },
+        "op": {
+          "type": "string",
+          "enum": [
+            "switch_tab"
+          ]
+        },
+        "result": {
+          "$ref": "#/definitions/StepResultV3"
+        },
+        "state": {
+          "description": "Observation id immediately before this action.",
+          "type": "string"
+        }
+      }
+    },
     {
       "description": "Fields shared by every step variant (flattened in JSON).",
       "type": "object",

crates/bsk-protocol/schema/trace_v3.json

@@ -173,6 +173,36 @@
             }
           }
         },
+        {
+          "description": "Fields shared by every step variant (flattened in JSON).",
+          "type": "object",
+          "required": [
+            "id",
+            "op",
+            "result",
+            "state"
+          ],
+          "properties": {
+            "id": {
+              "type": "integer",
+              "format": "uint32",
+              "minimum": 0.0
+            },
+            "op": {
+              "type": "string",
+              "enum": [
+                "switch_tab"
+              ]
+            },
+            "result": {
+              "$ref": "#/definitions/StepResultV3"
+            },
+            "state": {
+              "description": "Observation id immediately before this action.",
+              "type": "string"
+            }
+          }
+        },
         {
           "description": "Fields shared by every step variant (flattened in JSON).",
           "type": "object",

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

@@ -32,6 +32,16 @@ pub struct RecordStartParams {
     pub url: Option<String>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub purpose: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub max_page_tokens: Option<u32>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub redact_values: Option<bool>,
+    /// Desired trace export format. Omitted means v2; `3` requests v3.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub trace_version: Option<u32>,
+    /// Client can decode the v3 `switch_tab` step variant.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub supports_tab_switch_steps: Option<bool>,
 }
 
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize, JsonSchema)]
@@ -267,6 +277,249 @@ mod tests {
     use super::*;
     use serde_json::json;
 
+    fn sample_common(id: u32, state: &str, result_state: &str) -> StepCommonV3 {
+        StepCommonV3 {
+            id,
+            state: state.into(),
+            result: StepResultV3 {
+                state: result_state.into(),
+            },
+        }
+    }
+
+    fn sample_target() -> TargetDescriptorV3 {
+        TargetDescriptorV3 {
+            element_ref: Some("e21".into()),
+            role: Some("button".into()),
+            name: Some("发布".into()),
+            ctx: Some("金桔柠檬 6 号".into()),
+            unmatched: false,
+        }
+    }
+
+    fn sample_trace() -> TraceV3 {
+        TraceV3 {
+            version: TRACE_VERSION_V3,
+            purpose: Some("把草稿商品发布上架".into()),
+            started_at: Some("2026-08-10T02:10:41.080Z".into()),
+            recorded_at: "2026-08-10T02:12:55.360Z".into(),
+            stopped_by: StopReason::UserFinish,
+            entry: TraceEntry {
+                start_url: "https://example.com/".into(),
+            },
+            recorder: RecorderInfo {
+                bsk: "0.1.10".into(),
+                vom: VOM_FORMAT_VERSION,
+            },
+            states: vec![
+                TraceStateV3 {
+                    id: "s1".into(),
+                    url: "https://example.com/".into(),
+                    title: Some("Example Domain".into()),
+                    body: "@vom 1\nRootWebArea \"Example Domain\"".into(),
+                    truncated: false,
+                },
+                TraceStateV3 {
+                    id: "s2".into(),
+                    url: "https://shop.example.com/products?status=draft".into(),
+                    title: Some("商品管理".into()),
+                    body: "@vom 1\nRootWebArea \"商品管理\"".into(),
+                    truncated: false,
+                },
+            ],
+            steps: vec![
+                StepV3::Navigate {
+                    common: sample_common(1, "s1", "s2"),
+                    to: "https://shop.example.com/products?status=draft".into(),
+                    cause: NavigationCause::UserTyped,
+                },
+                StepV3::Fill {
+                    common: sample_common(2, "s2", "s2"),
+                    target: TargetDescriptorV3 {
+                        element_ref: Some("e12".into()),
+                        role: Some("textbox".into()),
+                        name: Some("搜索商品".into()),
+                        ctx: None,
+                        unmatched: false,
+                    },
+                    value: "金桔柠檬".into(),
+                    commit: FillCommit::Enter,
+                    redacted: false,
+                },
+                StepV3::Click {
+                    common: sample_common(3, "s2", "s2"),
+                    target: sample_target(),
+                },
+            ],
+        }
+    }
+
+    #[test]
+    fn step_click_round_trips() {
+        let step = StepV3::Click {
+            common: sample_common(1, "s1", "s2"),
+            target: sample_target(),
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v.get("op").and_then(|v| v.as_str()), Some("click"));
+        assert_eq!(v.get("state").and_then(|v| v.as_str()), Some("s1"));
+        assert_eq!(v["result"]["state"], "s2");
+        assert_eq!(v["target"]["ref"], "e21");
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
+    #[test]
+    fn step_fill_with_commit_round_trips() {
+        let step = StepV3::Fill {
+            common: sample_common(2, "s2", "s3"),
+            target: TargetDescriptorV3 {
+                element_ref: Some("e12".into()),
+                role: Some("textbox".into()),
+                name: Some("搜索商品".into()),
+                ctx: None,
+                unmatched: false,
+            },
+            value: "browser skill".into(),
+            commit: FillCommit::Enter,
+            redacted: false,
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["op"], "fill");
+        assert_eq!(v["commit"], "enter");
+        assert!(v.get("redacted").is_none());
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
+    #[test]
+    fn step_fill_password_is_redacted() {
+        let step = StepV3::Fill {
+            common: sample_common(1, "s1", "s1"),
+            target: TargetDescriptorV3 {
+                element_ref: Some("e3".into()),
+                role: Some("textbox".into()),
+                name: Some("密码".into()),
+                ctx: None,
+                unmatched: false,
+            },
+            value: "***".into(),
+            commit: FillCommit::Blur,
+            redacted: true,
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["value"], "***");
+        assert_eq!(v["redacted"], true);
+    }
+
+    #[test]
+    fn step_navigate_with_cause_round_trips() {
+        let step = StepV3::Navigate {
+            common: sample_common(1, "s1", "s2"),
+            to: "https://example.com".into(),
+            cause: NavigationCause::UserTyped,
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["op"], "navigate");
+        assert_eq!(v["cause"], "user_typed");
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
+    #[test]
+    fn step_switch_tab_round_trips() {
+        let step = StepV3::SwitchTab {
+            common: sample_common(2, "s2", "s5"),
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["op"], "switch_tab");
+        assert_eq!(v["state"], "s2");
+        assert_eq!(v["result"]["state"], "s5");
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
+    #[test]
+    fn trace_v3_round_trips() {
+        let trace = sample_trace();
+        let v = serde_json::to_value(&trace).unwrap();
+        assert_eq!(v.get("version").and_then(|v| v.as_u64()), Some(3));
+        assert!(v.get("pages").is_none());
+        assert_eq!(v["recorder"]["vom"], 1);
+        assert_eq!(v["states"].as_array().unwrap().len(), 2);
+        let round: TraceV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, trace);
+    }
+
+    #[test]
+    fn default_fields_are_omitted() {
+        let step = StepV3::Click {
+            common: sample_common(1, "s1", "s1"),
+            target: TargetDescriptorV3 {
+                element_ref: Some("e1".into()),
+                role: Some("button".into()),
+                name: Some("OK".into()),
+                ctx: None,
+                unmatched: false,
+            },
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert!(v.get("unmatched").is_none());
+        assert!(v["target"].get("ctx").is_none());
+        assert!(v["target"].get("unmatched").is_none());
+    }
+
+    #[test]
+    fn record_start_trace_options_are_explicit_and_optional() {
+        let legacy = RecordStartParams {
+            session_id: "session".into(),
+            tab_id: None,
+            url: None,
+            purpose: None,
+            max_page_tokens: None,
+            redact_values: None,
+            trace_version: None,
+            supports_tab_switch_steps: None,
+        };
+        let legacy_value = serde_json::to_value(legacy).unwrap();
+        assert!(legacy_value.get("trace_version").is_none());
+        assert!(legacy_value.get("max_page_tokens").is_none());
+        assert!(legacy_value.get("supports_tab_switch_steps").is_none());
+
+        let v3 = RecordStartParams {
+            session_id: "session".into(),
+            tab_id: None,
+            url: None,
+            purpose: None,
+            max_page_tokens: Some(4_000),
+            redact_values: Some(true),
+            trace_version: Some(TRACE_VERSION_V3),
+            supports_tab_switch_steps: Some(true),
+        };
+        let v3_value = serde_json::to_value(v3).unwrap();
+        assert_eq!(v3_value["trace_version"], TRACE_VERSION_V3);
+        assert_eq!(v3_value["max_page_tokens"], 4_000);
+        assert_eq!(v3_value["redact_values"], true);
+        assert_eq!(v3_value["supports_tab_switch_steps"], true);
+    }
+
+    #[test]
+    fn unmatched_target_serializes_flag() {
+        let step = StepV3::Click {
+            common: sample_common(1, "s1", "s2"),
+            target: TargetDescriptorV3 {
+                element_ref: None,
+                role: Some("button".into()),
+                name: Some("发布".into()),
+                ctx: None,
+                unmatched: true,
+            },
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["target"]["unmatched"], true);
+        assert!(v["target"].get("ref").is_none());
+    }
+
     #[test]
     fn recorded_trace_classifies_v2_and_v3() {
         let v2 = json!({
@@ -452,4 +705,43 @@ mod tests {
         assert!(schema["definitions"].get("StepV2").is_some());
         assert!(schema["definitions"].get("StepV3").is_some());
     }
+
+    #[test]
+    fn extension_trace_deserializes() {
+        let v = json!({
+            "version": 3,
+            "recorded_at": "2026-07-21T08:00:00Z",
+            "started_at": "2026-07-21T07:59:00Z",
+            "purpose": "demo",
+            "stopped_by": "user_finish",
+            "entry": { "start_url": "https://example.com/editor" },
+            "recorder": { "bsk": "0.1.10", "vom": 1 },
+            "states": [
+                { "id": "s1", "url": "https://example.com/editor", "body": "@vom 1" },
+                { "id": "s2", "url": "https://example.com/p/99", "body": "@vom 1" }
+            ],
+            "steps": [
+                {
+                    "op": "fill",
+                    "id": 1,
+                    "state": "s1",
+                    "result": { "state": "s1" },
+                    "target": { "ref": "e1", "role": "textbox", "name": "标题" },
+                    "value": "hello",
+                    "commit": "blur"
+                },
+                {
+                    "op": "click",
+                    "id": 2,
+                    "state": "s1",
+                    "result": { "state": "s2" },
+                    "target": { "ref": "e2", "role": "button", "name": "发布" }
+                }
+            ]
+        });
+        let trace: TraceV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(trace.version, 3);
+        assert_eq!(trace.states.len(), 2);
+        assert_eq!(trace.steps.len(), 2);
+    }
 }

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

@@ -126,6 +126,10 @@ pub enum StepV3 {
         to: String,
         cause: NavigationCause,
     },
+    SwitchTab {
+        #[serde(flatten)]
+        common: StepCommonV3,
+    },
     Click {
         #[serde(flatten)]
         common: StepCommonV3,
@@ -340,6 +344,19 @@ mod tests {
         assert_eq!(round, step);
     }
 
+    #[test]
+    fn step_switch_tab_round_trips() {
+        let step = StepV3::SwitchTab {
+            common: sample_common(2, "s2", "s5"),
+        };
+        let v = serde_json::to_value(&step).unwrap();
+        assert_eq!(v["op"], "switch_tab");
+        assert_eq!(v["state"], "s2");
+        assert_eq!(v["result"]["state"], "s5");
+        let round: StepV3 = serde_json::from_value(v).unwrap();
+        assert_eq!(round, step);
+    }
+
     #[test]
     fn trace_v3_round_trips() {
         let trace = sample_trace();

packages/i18n/src/locales/en-US/extension.json

@@ -48,7 +48,7 @@
     "record": {
       "sectionTitle": "Action recording",
       "cardDesc": "Record your actions for Agent reference",
-      "sectionHint": "Generates a recording instruction — send it to your Agent to start recording your actions; the Agent can then use the recording to automate similar tasks.",
+      "sectionHint": "Generates a recording instruction — send it to your Agent to start recording your actions; the Agent can then use the resulting trace bundle to automate similar tasks.",
       "topicLabel": "Topic (optional)",
       "topicPlaceholder": "e.g. Publish an article",
       "startUrlLabel": "Starting URL (optional)",
@@ -56,7 +56,7 @@
       "copyButton": "Copy recording instructions",
       "copied": "Copied",
       "hintDisconnected": "Available when connected",
-      "promptTemplate": "Use BrowserSkill's `bsk` CLI to record the browser actions I'm about to demonstrate.\n\nSteps:\n1. Run: {{command}}\n2. Once you confirm it's started, I'll operate in the opened window myself.\n3. After I click Finish, read the returned trace.json and summarize the actions (pages + steps); don't re-run or \"verify\"."
+      "promptTemplate": "Use BrowserSkill's `bsk` CLI to record the browser actions I'm about to demonstrate.\n\nSteps:\n1. Run: {{command}}\n2. Once you confirm it's started, I'll operate in the opened window myself.\n3. After I click Finish, read the written `./trace` bundle (`trace.json` + `states/`) and summarize what I did."
     }
   },
   "controlOverlay": {

packages/i18n/src/locales/zh-CN/extension.json

@@ -48,7 +48,7 @@
     "record": {
       "sectionTitle": "操作录制",
       "cardDesc": "录制你的操作，供 Agent 参考",
-      "sectionHint": "生成一段录制指令，发给 Agent 后可以启动插件录制用户操作，之后 Agent 可以参考录制结果自动完成同类任务。",
+      "sectionHint": "生成一段录制指令，发给 Agent 后可以启动插件录制用户操作，之后 Agent 可以参考写出的 trace 目录包自动完成同类任务。",
       "topicLabel": "操作主题（可选）",
       "topicPlaceholder": "例如：发布一篇文章",
       "startUrlLabel": "起始网址（可选）",
@@ -56,7 +56,7 @@
       "copyButton": "复制录制指令",
       "copied": "已复制",
       "hintDisconnected": "连接后可用",
-      "promptTemplate": "用 BrowserSkill 的 `bsk` CLI 录制我接下来的浏览器操作。\n\n步骤：\n1. 执行：{{command}}\n2. 你确认已开始后，我会在打开的窗口里自己操作。\n3. 我点“结束”后，读取返回的 trace.json 并总结操作（pages + steps），不要重跑或“验证”。"
+      "promptTemplate": "用 BrowserSkill 的 `bsk` CLI 录制我接下来的浏览器操作。\n\n步骤：\n1. 执行：{{command}}\n2. 你确认已开始后，我会在打开的窗口里自己操作。\n3. 我点“结束”后，读取写出的 `./trace` 目录包（`trace.json` + `states/`），总结我做了什么。"
     }
   },
   "controlOverlay": {

skill/SKILL.md

@@ -265,19 +265,27 @@ retry — complete the task autonomously or stop gracefully.
 
 ### Recording — `bsk record`
 
-Capture the user's own actions in the Agent Window to a `trace.json`, for later LLM-driven automation:
+Capture the user's own actions in the Agent Window to a **trace bundle**, for later LLM-driven automation. New CLI builds request **trace v3** (page observations + action chain); older extensions may still return **trace v2** (actions only), which the CLI exports as a single `trace.json` without `states/`.
 
 ```bash
-bsk record start --browser <instance-id-or-label> [--url https://…] [--purpose "publish a wiki doc"] [--output trace.json]
+bsk record start --browser <instance-id-or-label> \
+  [--url https://…] [--purpose "publish a wiki doc"] \
+  [--max-page-tokens 3000] [--redact-values] \
+  [--output trace]
 # `--url` is optional; default https://example.com/ when omitted (must be http(s)).
-# Blocks until the user clicks Finish in the recording panel, then writes ./trace.json and closes the window.
+# Blocks until the user clicks Finish in the recording panel, then writes:
+#   trace/trace.json    — action chain (+ state index when v3)
+#   trace/states/       — v3 only: one `sN.txt` observe snapshot per settled page state
 
-bsk record stop [--output trace.json]   # terminal fallback if the browser panel is unavailable
+bsk record stop [--output trace]   # terminal fallback if the browser panel is unavailable
 ```
 
-- The trace is a **record-only action log** (a `pages[]` dictionary + `navigate`/`click`/`fill`/`select`/`press` steps with `target` descriptors). It records *what the user did*; deciding which inputs are variable is left to the executing agent.
+- **v3 bundle (preferred):** `--output` is a directory (default `./trace`) containing `trace.json` and `states/`. `trace.json` lists `states[]` (page observation ids) and `steps[]` (each step binds `state` = observe snapshot *before* the action and `result.state` = snapshot *after* settle). Page bodies live in `states/sN.txt` using the same VOM format as `bsk observe`.
+- **v2 fallback:** when the connected extension is older, export may contain only legacy `trace.json` with `pages[]` action context and no `states/` observation files. Update the extension for full v3 bundles.
+- Each `states[]` entry is one **settled page observation** (captured after recording start, navigation landing, or action settle — not on a timer).
+- `target.ref` values like `@e12` exist **only inside** the bundle for disambiguation; do **not** copy `@eN` refs into SKILL.md or agent runbooks — use visible names from the observation text instead.
 - `--purpose` is optional context metadata; it does **not** change what gets captured.
-- There is **no** `bsk replay` — to redo a flow, read the trace and reuse the existing `session` / `snapshot` / `@eN` / `click` / `fill` tools. Follow **Stop when the goal is met**.
+- `--redact-values` masks all form values in page files as `[filled]` / `[empty]`.
 - Do **not** record on banking/SSO/password-manager pages; passwords are redacted but traces may still contain sensitive text.
 
 ## Error handling