Merge pull request #173 from Tencent/release/0.2.0

Release/0.2.0
test: update popup version display assertions for CLI/Ext labels
2026-09-10 13:01:23 +08:00 · 2026-09-02 19:00:21 +08:00 · 2026-09-02 18:32:33 +08:00 · 2026-09-02 18:26:35 +08:00 · 2026-09-02 18:17:56 +08:00 · 2026-09-02 18:05:32 +08:00
264 changed files with 35197 additions and 4169 deletions
@@ -325,3 +325,180 @@ jobs:

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

 # Logs
 *.log

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

@@ -0,0 +1,92 @@
+# Changelog
+
+All notable changes to BrowserSkill will be documented in this file.
+The format is based on [Keep a Changelog](https://keepachangelog.com/).
+
+Starting from 0.2.0, CLI / Extension / DSH Plugin share the same version number.
+
+## [Unreleased]
+
+## [0.2.0] - 2026-09-02
+
+### Added
+- File transfer: upload and download support across CLI, Extension, and DSH Plugin
+- File transfer: drag-and-drop upload (`drop-to-upload`)
+- VOM semantic graph, name enrichment, and hover perception modules
+- VOM hover probing (opt-in via `observe` parameter)
+- DSH Plugin: browser tool parity with CLI commands
+- Edge Add-ons automated publishing in CI
+- Protocol upgrade reminder when CLI / Extension protocol versions differ
+- Browser evaluation harness (`evals/browser/`)
+- Unified release script (`scripts/release.mjs`)
+
+### Changed
+- **Version scheme**: all three components now share the same semver
+- VOM rendering algorithm optimizations
+- Leaner SKILL.md agent instructions
+- DSH Plugin: simplified browser commands
+- Borrow confirmation UX — proactive focus and longer timeout
+- PiP window now has a close button
+
+### Fixed
+- Screenshot media type detection (was hard-coded to `image/png`)
+- DSH Plugin session lifecycle stability
+- DSH Plugin Cordis package ID mismatch
+- Observation thumbnail media type sniffing
+- Upload/download race conditions and layout bypass issues
+- VOM repeated name and safety policy issues
+
+---
+
+*Previous releases used independent version numbers per component.*
+
+## CLI 0.1.11 / Extension 0.1.7 / DSH Plugin 0.1.2 — 2026-08-26 ~ 2026-08-29
+
+### Added
+- DSH Plugin sidebar integration, session lifecycle, and archive cleanup
+- Recorder iframe and OOPIF support
+
+### Changed
+- VOM functional refactor
+
+### Fixed
+- Recorder safety policy and bug fixes
+
+## CLI 0.1.10 / Extension 0.1.6 — 2026-08-08
+
+### Added
+- VOM observation recording and settled-state detection
+- Record overlay timer
+
+### Fixed
+- Browser keepalive disconnect handling
+
+## CLI 0.1.9 / Extension 0.1.5 — 2026-07-29
+
+### Added
+- CLI auto-update mechanism
+- Trace v3 protocol and recorder
+
+### Fixed
+- MV3 keepalive disconnect
+
+## CLI 0.1.8 / Extension 0.1.4 — 2026-07-22
+
+### Added
+- More browser interaction actions
+
+### Fixed
+- Windows named-pipe hash-only path issue
+
+## CLI 0.1.7 / Extension 0.1.3 — 2026-07-07
+
+Initial public release pair.
+
+## CLI 0.1.6 — 2026-06-30
+
+### Fixed
+- Minor CLI fixes
+
+## CLI 0.1.5 / Extension 0.1.2 — 2026-06-22
+
+First tagged releases.
@@ -134,9 +134,10 @@ dependencies = [

 [[package]]
 name = "bsk"
-version = "0.1.10"
+version = "0.2.0"
 dependencies = [
 "anyhow",
+ "base64",
 "bsk-protocol",
 "clap",
 "console",
@@ -168,7 +169,7 @@ dependencies = [

 [[package]]
 name = "bsk-protocol"
-version = "0.1.10"
+version = "0.2.0"
 dependencies = [
 "schemars",
 "semver",
@@ -7,7 +7,7 @@ members = [
 default-members = ["crates/bsk-cli"]

 [workspace.package]
-version = "0.1.10"
+version = "0.2.0"
 edition = "2024"
 rust-version = "1.85"
 license = "MIT"
@@ -36,13 +36,14 @@ flate2 = "1.1.9"
 tar = "0.4.46"
 zip = { version = "7.2.0", default-features = false, features = ["deflate"] }
 sha2 = "0.11.0"
+base64 = "0.22"
 tempfile = "3"
 nix = { version = "0.29", features = ["signal", "process"] }
 rand = "0.8"
 uuid = { version = "1", features = ["v4", "serde"] }

 # Workspace crates (version required for `cargo publish` of dependents)
-bsk-protocol = { version = "0.1.9", path = "crates/bsk-protocol" }
+bsk-protocol = { version = "0.2.0", path = "crates/bsk-protocol" }

 [profile.release]
 strip = "symbols"
@@ -208,6 +208,7 @@ The repository is a Cargo + pnpm workspace:
 - `apps/extension` — browser extension
 - `packages/ui` and `packages/i18n` — shared extension UI support
 - `packages/dsh-plugin-browserskill` — DeepSeek Harness plugin (`@wxg-prc-cpg/browser-skill-dsh-plugin`)
+- [`evals/browser`](evals/browser/README.md) — deterministic local pages and agent-neutral browser capability evaluation

 ## License

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

 ## 许可证

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

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

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

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

 ## 2. Single Purpose

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

 ## 3. Data the Extension Accesses

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

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

 - Send any data to remote servers, the Extension's authors, or any third party.
 - Call any LLM, AI, or cloud API. The Extension contains no API keys, model identifiers, or remote endpoints.
- Read or transmit cookies, browsing history, bookmarks, downloads, saved passwords, or autofill data.
+- Read or transmit cookies, browsing history, bookmarks, saved passwords, or autofill data. It observes only the download initiated by an active `bsk download` call, not download history generally.
 - Use webcam, microphone, geolocation, or any device sensor.
 - Include analytics, telemetry, crash reporting, advertising SDKs, or fingerprinting code.
 - Track users across websites or across sessions.
@@ -50,6 +51,7 @@ The Extension requests the following Chrome permissions. Each is used solely for
 - **`alarms`** — Periodically wake the service worker to keep the local WebSocket connection alive.
 - **`idle`** — Detect when the device returns from idle/locked so the Extension can promptly re-establish the local WebSocket connection after the machine wakes. No idle data is stored or transmitted.
 - **`notifications`** — Show a system notification to obtain user approval before the agent borrows a user-owned tab.
+- **`downloads`** — Correlate and route the one browser download initiated by an active `bsk download` command. If that claimed transaction fails, BrowserSkill cancels an in-progress file or removes its completed temporary browser file. It is not used to enumerate download history or alter unclaimed downloads.
 - **`storage`** — Persist a random instance ID and optional label in `chrome.storage.local`.
 - **Host permission `<all_urls>`** — Inject a small status overlay (showing "Agent Active") on pages controlled by the agent, and enable automation across whatever sites the user directs the agent to. The Extension does **not** read or transmit page content from sites the agent is not actively driving.

@@ -61,6 +63,7 @@ All Extension activity stays on the user's local device. The only network traffi

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

 ## 8. User Control

@@ -0,0 +1,81 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <title>BrowserSkill file-transfer fixture</title>
+    <style>
+      body { font: 16px system-ui; max-width: 760px; margin: 48px auto; }
+      .actions { display: flex; gap: 12px; align-items: center; margin: 24px 0; }
+      button, a { padding: 10px 16px; border: 1px solid #777; border-radius: 8px; }
+      a[aria-disabled="true"] { opacity: .45; pointer-events: none; }
+      #drop { padding: 36px; border: 3px dashed #777; border-radius: 12px; text-align: center; }
+      #drop.dragging { border-color: #2563eb; background: #eff6ff; }
+      img { display: block; max-width: 480px; max-height: 360px; margin-top: 20px; }
+    </style>
+  </head>
+  <body>
+    <h1>Upload then download the same image</h1>
+    <p id="status">No image selected</p>
+    <div class="actions">
+      <button id="upload" type="button">Upload through file input</button>
+      <input id="file" type="file" accept="image/png" hidden />
+      <a id="download" aria-disabled="true">Download uploaded image</a>
+    </div>
+    <div id="drop" role="button" tabindex="0">Drop an image here</div>
+    <img id="preview" alt="Uploaded image preview" hidden />
+    <script>
+      const input = document.querySelector('#file');
+      const upload = document.querySelector('#upload');
+      const drop = document.querySelector('#drop');
+      const download = document.querySelector('#download');
+      const preview = document.querySelector('#preview');
+      const status = document.querySelector('#status');
+      let objectUrl;
+
+      window.__bskTransferFixture = { events: [], result: null };
+
+      function accept(file, mechanism) {
+        if (!file) return;
+        if (objectUrl) URL.revokeObjectURL(objectUrl);
+        objectUrl = URL.createObjectURL(file);
+        preview.src = objectUrl;
+        preview.hidden = false;
+        download.href = objectUrl;
+        download.download = file.name;
+        download.removeAttribute('aria-disabled');
+        status.textContent = `Ready via ${mechanism}: ${file.name} (${file.size} bytes)`;
+        window.__bskTransferFixture.result = {
+          mechanism,
+          name: file.name,
+          size: file.size,
+          type: file.type,
+          hasPathProperty: 'path' in file,
+        };
+      }
+
+      upload.addEventListener('click', () => input.click());
+      input.addEventListener('change', () => accept(input.files[0], 'input'));
+
+      for (const type of ['dragenter', 'dragover']) {
+        drop.addEventListener(type, event => {
+          const types = [...event.dataTransfer.types];
+          window.__bskTransferFixture.events.push({ type, types });
+          if (!types.includes('Files')) return;
+          event.preventDefault();
+          drop.classList.add('dragging');
+        });
+      }
+      drop.addEventListener('dragleave', () => drop.classList.remove('dragging'));
+      drop.addEventListener('drop', event => {
+        window.__bskTransferFixture.events.push({
+          type: 'drop',
+          types: [...event.dataTransfer.types],
+          fileCount: event.dataTransfer.files.length,
+        });
+        event.preventDefault();
+        drop.classList.remove('dragging');
+        accept(event.dataTransfer.files[0], 'drop');
+      });
+    </script>
+  </body>
+</html>
@@ -1,6 +1,6 @@
 {
  "name": "@browser-skill/extension",
-  "version": "0.1.6",
+  "version": "0.2.0",
  "private": true,
  "type": "module",
  "scripts": {
@@ -23,7 +23,7 @@ describe("BorrowConfirmationOverlay", () => {
            id: "req-1",
            isActiveTab: true,
            tabTitle: "Example",
-            timeoutMs: 5000,
+            timeoutMs: 60_000,
            onAllow,
            onDeny,
          },
@@ -32,7 +32,7 @@ describe("BorrowConfirmationOverlay", () => {
    );

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

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

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

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

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

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

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

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

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

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

+function captureGeometry(el: Element): RecordStepPayload["geometry"] {
+  const rect = el.getBoundingClientRect();
+  return {
+    rect: { x: rect.x, y: rect.y, w: rect.width, h: rect.height },
+    tag: el.tagName.toLowerCase(),
+  };
+}
+
+function geometryForEventTarget(
+  target: EventTarget | null,
+): RecordStepPayload["geometry"] | undefined {
+  if (!(target instanceof Element)) return undefined;
+  const clickable = target.closest(
+    'a,button,input,select,textarea,[role="button"],[role="link"],[role="menuitem"],[contenteditable="true"]',
+  );
+  return captureGeometry(clickable ?? target);
+}
+
 function fillableValue(el: FillableElement): string {
  if (el instanceof HTMLInputElement || el instanceof HTMLTextAreaElement) {
    return el.value;
@@ -232,7 +215,10 @@ function collectHoverTriggerLabelText(root: Element): string {
  return normalizeLabelText(text);
 }

-function compactHoverTargetName(el: Element, desc: TargetDescriptor): TargetDescriptor {
+function compactHoverTargetName(
+  el: Element,
+  desc: CaptureTargetDescriptor,
+): CaptureTargetDescriptor {
  if (!desc.name) return desc;
  const fullText = normalizeLabelText(el.textContent ?? "");
  const compactName = collectHoverTriggerLabelText(el);
@@ -250,7 +236,7 @@ function compactHoverTargetName(el: Element, desc: TargetDescriptor): TargetDesc
  return desc;
 }

-function isWeakHoverTarget(target: TargetDescriptor): boolean {
+function isWeakHoverTarget(target: CaptureTargetDescriptor): boolean {
  return !target.role && !target.name && target.tag === "div";
 }

@@ -261,9 +247,9 @@ function looksLikeAvatarElement(el: Element): boolean {

 function normalizeHoverTarget(
  el: Element,
-  desc: TargetDescriptor,
+  desc: CaptureTargetDescriptor,
  decision: HoverTriggerDecision,
-): TargetDescriptor {
+): CaptureTargetDescriptor {
  if (desc.role === "img" && !desc.name && looksLikeAvatarElement(el)) {
    return { ...desc, name: "image" };
  }
@@ -277,7 +263,7 @@ function normalizeHoverTarget(
  return desc;
 }

-function hoverTriggerSignals(el: Element, desc: TargetDescriptor) {
+function hoverTriggerSignals(el: Element, desc: CaptureTargetDescriptor) {
  if (!(el instanceof HTMLElement)) return null;
  const style = hoverTriggerStyle(el);
  return {
@@ -373,6 +359,7 @@ function scheduleInputCompletionCommit(
 export function startRecordCapture(
  _requestId: string,
  sendStep: (step: RecordStepPayload) => void,
+  options: { captureNavigation?: boolean } = {},
 ): RecordCaptureController {
  const emitStep = (step: RecordStepPayload) => {
    sendStep({ page_url: location.href, ...step });
@@ -411,14 +398,17 @@ export function startRecordCapture(
    emitStep({
      op: "fill",
      target: session.target,
+      geometry: captureGeometry(session.element),
      value,
+      commit: session.pendingCommit ?? "blur",
      ...(isPassword ? { redacted: true } : {}),
    });
  };

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

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

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

  return {
    dispose() {
@@ -933,93 +936,16 @@ export function startRecordCapture(
      document.removeEventListener("compositionend", onCompositionEnd, true);
      document.removeEventListener("change", onChange, true);
      document.removeEventListener("keydown", onKeyDown, true);
-      urlObserver.disconnect();
-      window.removeEventListener("hashchange", onUrlEvent);
-      window.removeEventListener("popstate", onUrlEvent);
-      window.removeEventListener("pagehide", commitFillSession);
-      history.pushState = originalPushState;
-      history.replaceState = originalReplaceState;
+      urlObserver?.disconnect();
+      if (captureNavigation) {
+        window.removeEventListener("hashchange", onUrlEvent);
+        window.removeEventListener("popstate", onUrlEvent);
+      }
+      window.removeEventListener("pagehide", onPageHide);
+      if (captureNavigation) {
+        history.pushState = originalPushState;
+        history.replaceState = originalReplaceState;
+      }
    },
  };
 }
-
-export type RecordContentMessage = RecordStartMessage | RecordStopMessage | RecordCancelMessage;
-
-export function isRecordContentMessage(msg: unknown): msg is RecordContentMessage {
-  return isRecordStartMessage(msg) || isRecordStopMessage(msg) || isRecordCancelMessage(msg);
-}
-
-export function handleRecordContentMessage(
-  message: RecordContentMessage,
-  state: {
-    activeRequestId: string | null;
-    capture: RecordCaptureController | null;
-    setActiveRequestId(id: string | null): void;
-    setCapture(capture: RecordCaptureController | null): void;
-    onStart(requestId: string, startedAtMs?: number): void;
-    onStop(): void;
-  },
-  sendResponse?: (response: RecordStartAck | RecordStopAck) => void,
-): boolean {
-  if (isRecordStartMessage(message)) {
-    if (!knownRecordRequests.has(message.requestId)) {
-      knownRecordRequests.add(message.requestId);
-      failedStepDeliveries.delete(message.requestId);
-    }
-    state.capture?.dispose();
-    state.setCapture(
-      startRecordCapture(message.requestId, (step) => {
-        sendRecordStep(message.requestId, step);
-      }),
-    );
-    state.setActiveRequestId(message.requestId);
-    state.onStart(message.requestId, message.startedAtMs);
-    sendResponse?.({ ok: true });
-    return sendResponse !== undefined;
-  }
-
-  if (isRecordStopMessage(message) || isRecordCancelMessage(message)) {
-    // Require an active recording that matches this requestId — otherwise a
-    // stray STOP/CANCEL (e.g. after teardown) would still run finishStop and
-    // clear overlay state even though nothing was capturing.
-    if (!state.activeRequestId || state.activeRequestId !== message.requestId) {
-      return false;
-    }
-    state.capture?.dispose();
-    state.setCapture(null);
-    const finishStop = () => {
-      state.onStop();
-      state.setActiveRequestId(null);
-    };
-    if (isRecordStopMessage(message) && sendResponse) {
-      const pending = [...(pendingStepSends.get(message.requestId) ?? [])];
-      void Promise.all(pending).then((delivered) => {
-        finishStop();
-        const succeeded = delivered.every(Boolean) && !failedStepDeliveries.has(message.requestId);
-        if (succeeded) {
-          failedStepDeliveries.delete(message.requestId);
-          knownRecordRequests.delete(message.requestId);
-        }
-        sendResponse(
-          succeeded
-            ? { ok: true }
-            : {
-                ok: false,
-                error: "failed to deliver one or more recorded steps",
-              },
-        );
-      });
-      return true;
-    }
-    if (isRecordCancelMessage(message)) {
-      failedStepDeliveries.delete(message.requestId);
-      knownRecordRequests.delete(message.requestId);
-    }
-    finishStop();
-    return false;
-  }
-
-  return false;
-}
-
-export { RECORD_CANCEL, RECORD_START, RECORD_STEP, RECORD_STOP };
@@ -0,0 +1,65 @@
+import {
+  isAcceptedRecordStepAck,
+  RECORD_STEP,
+  type RecordStepMessage,
+  type RecordStepPayload,
+} from "@/lib/record-bridge";
+
+export type SendRecordStepMessage = (message: RecordStepMessage) => Promise<unknown>;
+
+export class RecordStepDelivery {
+  readonly #requestId: string;
+  readonly #producerId: string;
+  readonly #send: SendRecordStepMessage;
+  readonly #pending = new Map<number, RecordStepPayload>();
+  #nextSequence = 1;
+  #tail = Promise.resolve();
+
+  constructor(
+    requestId: string,
+    send: SendRecordStepMessage = (message) => chrome.runtime.sendMessage(message),
+    producerId: string = crypto.randomUUID(),
+  ) {
+    this.#requestId = requestId;
+    this.#producerId = producerId;
+    this.#send = send;
+  }
+
+  enqueue(step: RecordStepPayload): void {
+    const sequence = this.#nextSequence;
+    this.#nextSequence += 1;
+    this.#pending.set(sequence, step);
+    void this.#schedule();
+  }
+
+  async flush(): Promise<boolean> {
+    await this.#tail;
+    await this.#schedule();
+    return this.#pending.size === 0;
+  }
+
+  #schedule(): Promise<void> {
+    const drain = () => this.#drain();
+    this.#tail = this.#tail.then(drain, drain);
+    return this.#tail;
+  }
+
+  async #drain(): Promise<void> {
+    for (const [sequence, step] of this.#pending) {
+      const message: RecordStepMessage = {
+        type: RECORD_STEP,
+        requestId: this.#requestId,
+        producerId: this.#producerId,
+        sequence,
+        step,
+      };
+      try {
+        const response = await this.#send(message);
+        if (!isAcceptedRecordStepAck(response, sequence)) return;
+        this.#pending.delete(sequence);
+      } catch {
+        return;
+      }
+    }
+  }
+}
@@ -0,0 +1,209 @@
+import {
+  markRecordingDocument,
+  type RecordingDocumentMarker,
+  waitForDocumentElement,
+} from "@/lib/recording/document-marker";
+import {
+  isRecordFrameStartMessage,
+  RECORD_FRAME_PORT,
+  RECORD_FRAME_QUERY,
+  RECORD_FRAME_START,
+  type RecordFramePortMessage,
+  type RecordFrameQueryResponse,
+  type RecordFrameStartMessage,
+} from "@/lib/recording/frame-bridge";
+import { type RecordCaptureController, startRecordCapture } from "../record-capture";
+import { RecordStepDelivery } from "../record-step-delivery";
+
+interface ActiveFrameRecording {
+  requestId: string;
+  producerId: string;
+  port: chrome.runtime.Port;
+  delivery: RecordStepDelivery;
+  capture: RecordCaptureController;
+  marker: RecordingDocumentMarker;
+}
+
+const RECORD_FRAME_REGISTER_TIMEOUT_MS = 5_000;
+
+export class RecordFrameAgent {
+  #active: ActiveFrameRecording | null = null;
+  #startPromise: Promise<{ ok: true } | { ok: false; error: string }> | null = null;
+  #disposed = false;
+
+  async start(
+    message: RecordFrameStartMessage,
+  ): Promise<{ ok: true } | { ok: false; error: string }> {
+    if (this.#active?.requestId === message.requestId) return { ok: true };
+    if (this.#disposed) return { ok: false, error: "recording document is disposed" };
+    if (this.#startPromise) {
+      await this.#startPromise;
+      return this.start(message);
+    }
+    if (this.#active) this.cancel(this.#active.requestId);
+    const starting = this.#start(message);
+    this.#startPromise = starting;
+    try {
+      return await starting;
+    } finally {
+      if (this.#startPromise === starting) this.#startPromise = null;
+    }
+  }
+
+  cancel(requestId: string): void {
+    const active = this.#active;
+    if (!active || active.requestId !== requestId) return;
+    active.capture.dispose();
+    active.marker.restore();
+    active.port.disconnect();
+    this.#active = null;
+  }
+
+  dispose(): void {
+    this.#disposed = true;
+    if (this.#active) this.cancel(this.#active.requestId);
+  }
+
+  async #start(
+    message: RecordFrameStartMessage,
+  ): Promise<{ ok: true } | { ok: false; error: string }> {
+    const producerId = crypto.randomUUID();
+    const root = await waitForDocumentElement();
+    if (this.#disposed) return { ok: false, error: "recording document is disposed" };
+    const marker = markRecordingDocument(producerId, root);
+    const port = chrome.runtime.connect({ name: RECORD_FRAME_PORT });
+    try {
+      await registerPort(port, message.requestId, producerId);
+    } catch {
+      marker.restore();
+      port.disconnect();
+      return { ok: false, error: "failed to register recording document" };
+    }
+    if (this.#disposed) {
+      marker.restore();
+      port.disconnect();
+      return { ok: false, error: "recording document is disposed" };
+    }
+
+    const delivery = new RecordStepDelivery(message.requestId, undefined, producerId);
+    const capture = startRecordCapture(
+      message.requestId,
+      (step) => {
+        marker.ensure();
+        delivery.enqueue(step);
+      },
+      { captureNavigation: window.top === window },
+    );
+    const active: ActiveFrameRecording = {
+      requestId: message.requestId,
+      producerId,
+      port,
+      delivery,
+      capture,
+      marker,
+    };
+    this.#active = active;
+    port.onMessage.addListener((raw: unknown) => {
+      const command = raw as Partial<RecordFramePortMessage>;
+      if (command.type === "stop" && command.requestId === active.requestId) {
+        void this.#stop(active, command.commandId);
+      } else if (command.type === "cancel" && command.requestId === active.requestId) {
+        this.cancel(active.requestId);
+      }
+    });
+    port.onDisconnect.addListener(() => {
+      if (this.#active !== active) return;
+      active.capture.dispose();
+      active.marker.restore();
+      this.#active = null;
+    });
+    return { ok: true };
+  }
+
+  async #stop(active: ActiveFrameRecording, commandId: string | undefined): Promise<void> {
+    if (!commandId || this.#active !== active) return;
+    active.capture.dispose();
+    const succeeded = await active.delivery.flush();
+    try {
+      active.port.postMessage({
+        type: "stopped",
+        requestId: active.requestId,
+        commandId,
+        ok: succeeded,
+        ...(succeeded ? {} : { error: "failed to deliver one or more recorded steps" }),
+      } satisfies RecordFramePortMessage);
+    } catch {
+      return;
+    }
+    if (!succeeded || this.#active !== active) return;
+    active.marker.restore();
+    this.#active = null;
+    active.port.disconnect();
+  }
+}
+
+function registerPort(
+  port: chrome.runtime.Port,
+  requestId: string,
+  producerId: string,
+): Promise<void> {
+  return new Promise((resolve, reject) => {
+    const timer = setTimeout(() => {
+      cleanup();
+      reject(new Error("recording document registration timed out"));
+    }, RECORD_FRAME_REGISTER_TIMEOUT_MS);
+    const cleanup = () => {
+      clearTimeout(timer);
+      port.onMessage.removeListener(onMessage);
+      port.onDisconnect.removeListener(onDisconnect);
+    };
+    const onMessage = (raw: unknown) => {
+      const message = raw as Partial<RecordFramePortMessage>;
+      if (
+        message.type !== "ready_ack" ||
+        message.requestId !== requestId ||
+        message.producerId !== producerId
+      ) {
+        return;
+      }
+      cleanup();
+      resolve();
+    };
+    const onDisconnect = () => {
+      cleanup();
+      reject(new Error("recording document port disconnected"));
+    };
+    port.onMessage.addListener(onMessage);
+    port.onDisconnect.addListener(onDisconnect);
+    port.postMessage({ type: "ready", requestId, producerId } satisfies RecordFramePortMessage);
+  });
+}
+
+export function attachRecordFrameAgent(): () => void {
+  const agent = new RecordFrameAgent();
+  const onMessage = (
+    message: unknown,
+    _sender: chrome.runtime.MessageSender,
+    sendResponse: (response: { ok: true } | { ok: false; error: string }) => void,
+  ) => {
+    if (!isRecordFrameStartMessage(message)) return false;
+    void agent.start(message).then(sendResponse);
+    return true;
+  };
+  chrome.runtime.onMessage.addListener(onMessage);
+  void chrome.runtime
+    .sendMessage({ type: RECORD_FRAME_QUERY })
+    .then((response: RecordFrameQueryResponse | undefined) => {
+      if (!response?.active || !response.requestId || response.startedAtMs === undefined) return;
+      return agent.start({
+        type: RECORD_FRAME_START,
+        requestId: response.requestId,
+        startedAtMs: response.startedAtMs,
+      });
+    })
+    .catch(() => {});
+  return () => {
+    chrome.runtime.onMessage.removeListener(onMessage);
+    agent.dispose();
+  };
+}
@@ -21,6 +21,7 @@ import {
  type OverlayMode,
 } from "@/lib/overlay-bridge";
 import { POPUP_PORT_NAME, type PopupInbound, type PopupOutbound } from "@/lib/popup-bridge";
+import { recordFrameCoordinator } from "@/lib/recording/frame-coordinator";
 import { attachSessionsLiveFlag } from "@/lib/sessions-live-flag";
 import { createDisconnectCleanup } from "@/session-manager/disconnect-cleanup";
 import { attachSessionEventHandler } from "@/session-manager/event-handler";
@@ -38,6 +39,7 @@ import {
  attachRecordFinishListener,
  attachRecordQueryListener,
  attachRecordStepListener,
+  type RecordRuntimeDeps,
 } from "@/tools/record";
 import { detectBrowserMeta } from "@/transport/handshake";
 import type { Transport } from "@/transport/transport";
@@ -145,10 +147,33 @@ export default defineBackground(() => {
      void sessionsLive.syncFromManager();
    },
  });
+  const recordDeps = {
+    tabsApi: chrome.tabs,
+    cdp,
+    frameCoordinator: recordFrameCoordinator,
+    sendToTab: (tabId: number, msg: Parameters<typeof chrome.tabs.sendMessage>[1]) =>
+      chrome.tabs.sendMessage(tabId, msg),
+    bypassOverlay: async (tabId: number, enabled: boolean) => {
+      try {
+        await chrome.tabs.sendMessage(tabId, {
+          type: OVERLAY_AUTOMATION_BYPASS,
+          enabled,
+        });
+      } catch {
+        // Content script may be unavailable on restricted pages.
+      }
+    },
+  } satisfies RecordRuntimeDeps;
+  recordFrameCoordinator.attach();
+  attachRecordStepListener(recordDeps);
+  attachRecordFinishListener(recordDeps);
+  attachRecordQueryListener(recordDeps);
+
  const dispatcher = new ToolDispatcher({
    transport,
    sessions,
    cdp,
+    recording: recordDeps,
    onSessionsChanged: onOverlaySessionStateChanged,
    onBrowserControlResumed,
    approveBorrow: (ctx) =>
@@ -170,27 +195,6 @@ export default defineBackground(() => {
    }),
  });
  dispatcher.start();
-  const recordDeps = {
-    tabsApi: chrome.tabs,
-    sendToTab: (tabId: number, msg: Parameters<typeof chrome.tabs.sendMessage>[1]) =>
-      chrome.tabs.sendMessage(tabId, msg),
-    bypassOverlay: async (tabId: number, enabled: boolean) => {
-      try {
-        await chrome.tabs.sendMessage(tabId, {
-          type: OVERLAY_AUTOMATION_BYPASS,
-          enabled,
-        });
-      } catch {
-        // Content script may be unavailable on restricted pages.
-      }
-    },
-  };
-  // Message listeners stay up (cheap; fire only for record message types).
-  // Tab / webNavigation observation attaches lazily while a recording is
-  // active — see ensureBrowserObservationListeners in tools/record.ts.
-  attachRecordStepListener();
-  attachRecordFinishListener(recordDeps);
-  attachRecordQueryListener(recordDeps);
  if (typeof chrome.notifications?.onClicked?.addListener === "function") {
    attachBorrowNotificationClickHandler({
      onClicked: chrome.notifications.onClicked,
@@ -11,11 +11,6 @@ import { createHelpRequestData } from "@/content/help-request";
 import overlayCss from "@/content/overlay.css?inline";
 import { OverlayController, shouldShowAgentControlOverlay } from "@/content/overlay-controller";
 import { RecordOverlay } from "@/content/RecordOverlay";
-import {
-  handleRecordContentMessage,
-  isRecordContentMessage,
-  type RecordCaptureController,
-} from "@/content/record-capture";
 import {
  type CaptureSuppressAck,
  type CaptureSuppressMessage,
@@ -45,11 +40,17 @@ import {
 } from "@/lib/overlay-bridge";
 import { sendInterrupt } from "@/lib/overlay-interrupt-client";
 import {
+  isRecordCancelMessage,
+  isRecordStartMessage,
+  isRecordStopMessage,
  RECORD_FINISH,
  RECORD_QUERY,
+  type RecordCancelMessage,
  type RecordQueryResponse,
  type RecordStartAck,
+  type RecordStartMessage,
  type RecordStopAck,
+  type RecordStopMessage,
 } from "@/lib/record-bridge";
 import type {
  BorrowCancelMessage,
@@ -69,7 +70,6 @@ export default defineContentScript({
    if (window.top !== window) return;

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

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

      if (
@@ -526,9 +518,6 @@ export default defineContentScript({
      chrome.runtime.onMessage.removeListener(onMessage);
      chrome.storage.onChanged.removeListener(onStorageChange);
      window.removeEventListener("pageshow", onPageShow);
-      // Restore history hooks / remove capture listeners before the CS unloads.
-      recordCapture?.dispose();
-      recordCapture = null;
      activeRecordRequestId = null;
    });
  },
@@ -122,8 +122,8 @@ describe("App", () => {

    expect(screen.queryByText(/^扩展 v/)).toBeNull();
    expect(screen.queryByText(/^daemon v/)).toBeNull();
-    expect(screen.getByTitle("扩展版本").textContent).toBe(EXTENSION_VERSION);
-    expect(screen.getByTitle("bsk 版本").textContent).toBe(mockDaemonVersion);
+    expect(screen.getByTitle("扩展版本").textContent).toBe(`Ext ${EXTENSION_VERSION}`);
+    expect(screen.getByTitle("bsk 版本").textContent).toBe(`CLI ${mockDaemonVersion}`);
    expect(screen.getByText("03c3e47f")).toBeTruthy();

    const copyButton = screen.getByRole("button", { name: "复制实例 ID" });
@@ -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"));
@@ -244,6 +247,41 @@ describe("App", () => {
    expect(copyButton.getAttribute("disabled")).not.toBeNull();
    expect(screen.getByText("连接后可用")).toBeTruthy();
  });
+
+  it("treats protocol drift as still connected and prompts an upgrade", async () => {
+    mockUseConnectionState.mockReturnValue({
+      snapshot: {
+        ...baseSnapshot,
+        state: "version_skew",
+        instanceId: "03c3e47f",
+        handshake: {
+          server: "bh",
+          version: mockDaemonVersion,
+          protocol_version: "1.0",
+        },
+      },
+      statusState: "version_skew",
+      setLabel,
+      setConnectionEnabled,
+    });
+
+    render(<App />);
+
+    expect(screen.getByText("已连接")).toBeTruthy();
+    expect(screen.getByText("可升级")).toBeTruthy();
+    expect(screen.queryByText("协议不一致")).toBeNull();
+    expect(screen.queryByText("Action needed")).toBeNull();
+    expect(screen.queryByText("兼容")).toBeNull();
+    const warning = screen.getByText(/协议版本不同，请及时升级/);
+    expect(warning.textContent).toContain("CLI 协议");
+    expect(warning.textContent).toContain("扩展协议");
+
+    openRecordView();
+    const copyButton = screen.getByRole("button", { name: "复制录制指令" });
+    expect(copyButton.getAttribute("disabled")).toBeNull();
+    fireEvent.click(copyButton);
+    expect(navigator.clipboard.writeText).toHaveBeenCalledTimes(1);
+  });
 });

 describe("control hints toggle", () => {
@@ -79,6 +79,7 @@ export function App() {
  }, [copiedTick]);

  const isSkewed = statusState === "version_skew";
+  const connectionLive = statusState === "connected" || isSkewed;
  const daemonVersion = snapshot.handshake?.version ?? "—";
  const daemonProtocol = snapshot.handshake?.protocol_version ?? "—";
  const extensionVersion = snapshot.extensionVersion || "—";
@@ -90,7 +91,7 @@ export function App() {
    setCopiedInstanceId(true);
  };

-  const recordReady = statusState === "connected" && Boolean(snapshot.instanceId);
+  const recordReady = connectionLive && Boolean(snapshot.instanceId);
  const recordPurpose = purposeDraft.trim();
  const recordStartUrl = startUrlDraft.trim();
  const recordCommand = snapshot.instanceId
@@ -206,12 +207,12 @@ export function App() {
            </div>
            {isSkewed && (
              <p
-                className="mt-2 text-xs leading-snug text-amber-600 dark:text-amber-400"
+                className="mt-2 text-xs leading-snug text-muted-foreground"
                data-slot="popup-version-skew-warning"
              >
                {t("popup.versionSkewWarning", {
                  extensionProtocol: PROTOCOL_VERSION,
-                  daemonProtocol,
+                  cliProtocol: daemonProtocol,
                })}
              </p>
            )}
@@ -266,9 +267,9 @@ export function App() {
            data-slot="popup-meta"
          >
            <div className="flex shrink-0 items-center gap-1">
-              <span title={t("popup.extensionVersionHint")}>{extensionVersion}</span>
+              <span title={t("popup.daemonVersionHint")}>CLI {daemonVersion}</span>
              <span aria-hidden>/</span>
-              <span title={t("popup.daemonVersionHint")}>{daemonVersion}</span>
+              <span title={t("popup.extensionVersionHint")}>Ext {extensionVersion}</span>
            </div>
            <div className="flex min-w-0 items-center justify-end gap-1">
              <span className="shrink-0">{t("popup.instanceTitle")}</span>
@@ -0,0 +1,14 @@
+import { attachRecordFrameAgent } from "@/content/recording/frame-agent";
+
+export default defineContentScript({
+  matches: ["<all_urls>"],
+  runAt: "document_start",
+  allFrames: true,
+  matchAboutBlank: true,
+  matchOriginAsFallback: true,
+
+  main(ctx) {
+    const dispose = attachRecordFrameAgent();
+    ctx.onInvalidated(dispose);
+  },
+});
@@ -2,7 +2,7 @@ import { describe, expect, it, vi } from "vitest";
 import {
  CAPTURE_SUPPRESS,
  type CaptureSuppressMessage,
-  withOverlaysHiddenForCapture,
+  withExtensionOverlayHidden,
 } from "../capture-suppress-bridge";

 function recordingSendToTab(events: string[]) {
@@ -12,12 +12,12 @@ function recordingSendToTab(events: string[]) {
  });
 }

-describe("withOverlaysHiddenForCapture", () => {
+describe("withExtensionOverlayHidden", () => {
  it("sends begin → fn → end and returns fn's result", async () => {
    const events: string[] = [];
    const sendToTab = recordingSendToTab(events);

-    const result = await withOverlaysHiddenForCapture(
+    const result = await withExtensionOverlayHidden(
      7,
      async () => {
        events.push("capture");
@@ -37,7 +37,7 @@ describe("withOverlaysHiddenForCapture", () => {
    const sendToTab = recordingSendToTab(events);

    await expect(
-      withOverlaysHiddenForCapture(
+      withExtensionOverlayHidden(
        7,
        async () => {
          events.push("capture");
@@ -55,7 +55,7 @@ describe("withOverlaysHiddenForCapture", () => {
    });
    const fn = vi.fn(async () => "shot");

-    const result = await withOverlaysHiddenForCapture(7, fn, sendToTab);
+    const result = await withExtensionOverlayHidden(7, fn, sendToTab);

    expect(result).toBe("shot");
    expect(fn).toHaveBeenCalledTimes(1);
@@ -69,7 +69,7 @@ describe("withOverlaysHiddenForCapture", () => {
      return { type: CAPTURE_SUPPRESS, ok: true };
    });

-    const result = await withOverlaysHiddenForCapture(7, async () => "shot", sendToTab);
+    const result = await withExtensionOverlayHidden(7, async () => "shot", sendToTab);

    expect(result).toBe("shot");
    expect(sendToTab).toHaveBeenCalledTimes(2);
@@ -26,20 +26,20 @@ function handshake(
 }

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

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

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

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

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

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

-    transport.emitMessage({ id: second.id, result: handshake("1.0", "1.0") });
+    transport.emitMessage({ id: second.id, result: handshake("1.1", "1.0") });
    await vi.waitFor(() => expect(controller.snapshot().state).toBe("connected"));
  });
 });
@@ -0,0 +1,101 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { CdpRunner } from "@/tools/shared";
+import { waitForDocumentSettled } from "../recording/document-settle";
+
+function quietCdp(): { cdp: CdpRunner; send: ReturnType<typeof vi.fn> } {
+  const send = vi.fn(async () => ({
+    result: { value: { idleMs: 1_000, readyState: "complete" } },
+  }));
+  return {
+    cdp: { send: send as unknown as CdpRunner["send"] },
+    send,
+  };
+}
+
+describe("waitForDocumentSettled", () => {
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
+  it("waits through the minimum observation floor before accepting a quiet page", async () => {
+    vi.useFakeTimers();
+    const { cdp, send } = quietCdp();
+
+    const settled = waitForDocumentSettled(cdp, { target: { tabId: 7 } });
+    await vi.advanceTimersByTimeAsync(180);
+
+    await expect(settled).resolves.toBe("quiet");
+    expect(send).toHaveBeenCalledTimes(3);
+  });
+
+  it("cancels before probing a superseded observation", async () => {
+    vi.useFakeTimers();
+    const { cdp, send } = quietCdp();
+
+    const controller = new AbortController();
+    const settled = waitForDocumentSettled(
+      cdp,
+      { target: { tabId: 7 } },
+      {
+        signal: controller.signal,
+      },
+    );
+    controller.abort();
+    await vi.advanceTimersByTimeAsync(60);
+
+    await expect(settled).resolves.toBe("cancelled");
+    expect(send).not.toHaveBeenCalled();
+  });
+
+  it("probes a same-process iframe through its isolated execution context", async () => {
+    vi.useFakeTimers();
+    const send = vi.fn(async (_tabId: number, method: string) => {
+      if (method === "Page.createIsolatedWorld") return { executionContextId: 91 };
+      return { result: { value: { idleMs: 1_000, readyState: "complete" } } };
+    });
+    const cdp: CdpRunner = { send: send as unknown as CdpRunner["send"] };
+
+    const settled = waitForDocumentSettled(cdp, {
+      target: { tabId: 7 },
+      frameId: "child-frame",
+    });
+    await vi.advanceTimersByTimeAsync(180);
+
+    await expect(settled).resolves.toBe("quiet");
+    expect(send).toHaveBeenCalledWith(
+      7,
+      "Page.createIsolatedWorld",
+      expect.objectContaining({ frameId: "child-frame" }),
+    );
+    expect(send).toHaveBeenCalledWith(
+      7,
+      "Runtime.evaluate",
+      expect.objectContaining({ contextId: 91 }),
+    );
+  });
+
+  it("routes an OOPIF probe through its CDP target session", async () => {
+    vi.useFakeTimers();
+    const send = vi.fn();
+    const sendToTarget = vi.fn(async (_target, method: string) => {
+      if (method === "Page.createIsolatedWorld") return { executionContextId: 27 };
+      return { result: { value: { idleMs: 1_000, readyState: "complete" } } };
+    });
+    const cdp: CdpRunner = {
+      send: send as unknown as CdpRunner["send"],
+      sendToTarget: sendToTarget as unknown as NonNullable<CdpRunner["sendToTarget"]>,
+    };
+
+    const target = { tabId: 7, sessionId: "oopif-session" };
+    const settled = waitForDocumentSettled(cdp, { target, frameId: "oopif-frame" });
+    await vi.advanceTimersByTimeAsync(180);
+
+    await expect(settled).resolves.toBe("quiet");
+    expect(send).not.toHaveBeenCalled();
+    expect(sendToTarget).toHaveBeenCalledWith(
+      target,
+      "Runtime.evaluate",
+      expect.objectContaining({ contextId: 27 }),
+    );
+  });
+});
@@ -0,0 +1,32 @@
+import { describe, expect, it } from "vitest";
+import {
+  isAcceptedRecordStepAck,
+  isRecordStepMessage,
+  RECORD_STEP,
+  type RecordStepMessage,
+} from "../record-bridge";
+
+const message: RecordStepMessage = {
+  type: RECORD_STEP,
+  requestId: "rec-1",
+  producerId: "document-1",
+  sequence: 1,
+  step: { op: "click", target: { tag: "button", name: "Submit" } },
+};
+
+describe("record step delivery protocol", () => {
+  it("requires a producer and a positive integer sequence", () => {
+    expect(isRecordStepMessage(message)).toBe(true);
+    expect(isRecordStepMessage({ ...message, producerId: "" })).toBe(false);
+    expect(isRecordStepMessage({ ...message, sequence: 0 })).toBe(false);
+    expect(isRecordStepMessage({ ...message, sequence: 1.5 })).toBe(false);
+  });
+
+  it("accepts only the acknowledgement for the sent sequence", () => {
+    expect(isAcceptedRecordStepAck({ ok: true, sequence: 2 }, 2)).toBe(true);
+    expect(isAcceptedRecordStepAck({ ok: true, sequence: 1 }, 2)).toBe(false);
+    expect(isAcceptedRecordStepAck({ ok: false, expectedSequence: 2, error: "gap" }, 2)).toBe(
+      false,
+    );
+  });
+});
@@ -0,0 +1,213 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { RECORD_FRAME_PORT, RECORD_FRAME_QUERY } from "../recording/frame-bridge";
+import { RecordFrameCoordinator } from "../recording/frame-coordinator";
+
+class ListenerSet<T extends (...args: never[]) => unknown> {
+  readonly listeners = new Set<T>();
+  addListener = (listener: T) => this.listeners.add(listener);
+  removeListener = (listener: T) => this.listeners.delete(listener);
+}
+
+function fakePort(sender: chrome.runtime.MessageSender) {
+  const messages: unknown[] = [];
+  const onMessage = new ListenerSet<(message: unknown) => void>();
+  const onDisconnect = new ListenerSet<() => void>();
+  return {
+    port: {
+      name: RECORD_FRAME_PORT,
+      sender,
+      onMessage,
+      onDisconnect,
+      postMessage: vi.fn((message: unknown) => messages.push(message)),
+      disconnect: vi.fn(),
+    } as unknown as chrome.runtime.Port,
+    messages,
+    receive(message: unknown) {
+      for (const listener of onMessage.listeners) listener(message);
+    },
+  };
+}
+
+describe("RecordFrameCoordinator", () => {
+  const onConnect = new ListenerSet<(port: chrome.runtime.Port) => void>();
+  const onMessage = new ListenerSet<
+    (
+      message: unknown,
+      sender: chrome.runtime.MessageSender,
+      sendResponse: (response: unknown) => void,
+    ) => boolean
+  >();
+
+  beforeEach(() => {
+    onConnect.listeners.clear();
+    onMessage.listeners.clear();
+    vi.stubGlobal("chrome", {
+      runtime: { onConnect, onMessage },
+    });
+  });
+
+  it("answers child-document queries for the initial tab before it is armed", () => {
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [],
+      sendToDocument: async () => ({ ok: true }),
+    });
+    coordinator.attach();
+    coordinator.begin("rec-1", 10, 3);
+
+    const query = (tabId: number) => {
+      let response: unknown;
+      for (const listener of onMessage.listeners) {
+        listener(
+          { type: RECORD_FRAME_QUERY },
+          {
+            tab: { id: tabId },
+            frameId: 7,
+            documentId: "child-document",
+          } as chrome.runtime.MessageSender,
+          (value) => {
+            response = value;
+          },
+        );
+      }
+      return response;
+    };
+
+    expect(query(3)).toEqual({ active: true, requestId: "rec-1", startedAtMs: 10 });
+    expect(query(4)).toEqual({ active: false });
+  });
+
+  it("starts a child Document that appears after the initial frame snapshot", async () => {
+    let notifyFrameNavigation:
+      | ((frame: {
+          tabId: number;
+          frameId: number;
+          documentId?: string;
+          lifecycle: "committed" | "completed";
+        }) => void)
+      | undefined;
+    const sendToDocument = vi.fn(async () => ({ ok: true }));
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [{ frameId: 0, documentId: "top-document" }],
+      sendToDocument,
+      subscribeFrameNavigation(listener) {
+        notifyFrameNavigation = listener;
+        return () => {};
+      },
+    });
+    coordinator.attach();
+    const onDocumentReady = vi.fn();
+    coordinator.begin("rec-1", 10, 3, onDocumentReady);
+    await coordinator.armTab("rec-1", 3);
+    sendToDocument.mockClear();
+
+    notifyFrameNavigation?.({
+      tabId: 3,
+      frameId: 7,
+      documentId: "late-child",
+      lifecycle: "completed",
+    });
+    await vi.waitFor(() => {
+      expect(sendToDocument).toHaveBeenCalledWith(
+        3,
+        { type: "bsk-record-frame-start", requestId: "rec-1", startedAtMs: 10 },
+        { documentId: "late-child" },
+      );
+    });
+    expect(onDocumentReady).not.toHaveBeenCalled();
+
+    const child = fakePort({
+      tab: { id: 3 },
+      frameId: 7,
+      documentId: "late-child",
+    } as chrome.runtime.MessageSender);
+    for (const listener of onConnect.listeners) listener(child.port);
+    child.receive({ type: "ready", requestId: "rec-1", producerId: "producer-1" });
+    notifyFrameNavigation?.({
+      tabId: 3,
+      frameId: 7,
+      documentId: "late-child",
+      lifecycle: "completed",
+    });
+    await vi.waitFor(() => {
+      expect(onDocumentReady).toHaveBeenCalledWith({
+        tabId: 3,
+        documentId: "late-child",
+        browserFrameId: 7,
+        producerId: "producer-1",
+      });
+    });
+  });
+
+  it("binds a producer to its sender Document and keeps final steps valid while stopping", async () => {
+    const sendToDocument = vi.fn(async () => ({ ok: true }));
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [
+        { frameId: 0, documentId: "top-document" },
+        { frameId: 7, documentId: "child-document" },
+      ],
+      sendToDocument,
+    });
+    coordinator.attach();
+    coordinator.begin("rec-1", 10, 3);
+    await expect(coordinator.armTab("rec-1", 3)).resolves.toBe(true);
+
+    const sender = {
+      tab: { id: 3 },
+      frameId: 7,
+      documentId: "child-document",
+    } as chrome.runtime.MessageSender;
+    const frame = fakePort(sender);
+    for (const listener of onConnect.listeners) listener(frame.port);
+    frame.receive({ type: "ready", requestId: "rec-1", producerId: "producer-1" });
+
+    expect(coordinator.sourceFor("rec-1", "producer-1", sender)).toEqual({
+      tabId: 3,
+      documentId: "child-document",
+      browserFrameId: 7,
+      producerId: "producer-1",
+    });
+
+    const stopping = coordinator.stop("rec-1");
+    expect(coordinator.sourceFor("rec-1", "producer-1", sender)).not.toBeNull();
+    const stop = frame.messages.find(
+      (message): message is { type: "stop"; commandId: string } =>
+        typeof message === "object" &&
+        message !== null &&
+        (message as { type?: string }).type === "stop",
+    );
+    expect(stop).toBeDefined();
+    frame.receive({
+      type: "stopped",
+      requestId: "rec-1",
+      commandId: stop!.commandId,
+      ok: true,
+    });
+    await expect(stopping).resolves.toBe(true);
+    expect(coordinator.sourceFor("rec-1", "producer-1", sender)).toBeNull();
+  });
+
+  it("rejects a producer used from another Document", async () => {
+    const coordinator = new RecordFrameCoordinator({
+      getAllFrames: async () => [{ frameId: 0, documentId: "top-document" }],
+      sendToDocument: async () => ({ ok: true }),
+    });
+    coordinator.attach();
+    coordinator.begin("rec-1", 10, 3);
+    await coordinator.armTab("rec-1", 3);
+    const sender = {
+      tab: { id: 3 },
+      frameId: 0,
+      documentId: "top-document",
+    } as chrome.runtime.MessageSender;
+    const frame = fakePort(sender);
+    for (const listener of onConnect.listeners) listener(frame.port);
+    frame.receive({ type: "ready", requestId: "rec-1", producerId: "producer-1" });
+
+    expect(
+      coordinator.sourceFor("rec-1", "producer-1", {
+        ...sender,
+        documentId: "other-document",
+      }),
+    ).toBeNull();
+  });
+});
@@ -0,0 +1,70 @@
+import { describe, expect, it } from "vitest";
+import {
+  RECORD_DOCUMENT_ATTRIBUTE,
+  recordingDocumentMarkerValue,
+} from "@/shared/recording-document-identity";
+import { markRecordingDocument } from "../recording/document-marker";
+import { ObservationNodeIndex } from "../recording/observation-capture";
+
+describe("recording document marker", () => {
+  it("rejects a non-random Document identity", () => {
+    expect(() => markRecordingDocument("user@example.com")).toThrow(
+      "recording Document identity must be a random UUID",
+    );
+  });
+
+  it("restores the Document attribute exactly", () => {
+    document.documentElement.setAttribute(RECORD_DOCUMENT_ATTRIBUTE, "page-value");
+    const producerId = "123e4567-e89b-42d3-a456-426614174000";
+    const marker = markRecordingDocument(producerId);
+
+    expect(document.documentElement.getAttribute(RECORD_DOCUMENT_ATTRIBUTE)).toBe(
+      recordingDocumentMarkerValue(producerId),
+    );
+    marker.restore();
+    expect(document.documentElement.getAttribute(RECORD_DOCUMENT_ATTRIBUTE)).toBe("page-value");
+    document.documentElement.removeAttribute(RECORD_DOCUMENT_ATTRIBUTE);
+  });
+
+  it("indexes the CDP scope from the safe frame identity", () => {
+    const index = new ObservationNodeIndex({
+      rootFrameId: "root",
+      frames: [
+        {
+          frameId: "child",
+          target: { tabId: 3, sessionId: "oopif-session" },
+          recordingDocumentId: "producer-1",
+        },
+      ],
+      matchNodes: [],
+      refs: [],
+    });
+
+    expect(index.documentScope("producer-1")).toEqual({
+      frameId: "child",
+      target: { tabId: 3, sessionId: "oopif-session" },
+    });
+  });
+
+  it("fails closed when a recording identity maps to multiple Documents", () => {
+    const index = new ObservationNodeIndex({
+      rootFrameId: "root",
+      frames: [
+        {
+          frameId: "left",
+          target: { tabId: 3, sessionId: "left-session" },
+          recordingDocumentId: "duplicate",
+        },
+        {
+          frameId: "right",
+          target: { tabId: 3, sessionId: "right-session" },
+          recordingDocumentId: "duplicate",
+        },
+      ],
+      matchNodes: [],
+      refs: [],
+    });
+
+    expect(index.documentScope("duplicate")).toBeUndefined();
+  });
+});
@@ -0,0 +1,146 @@
+import { describe, expect, it } from "vitest";
+import { ObservationNodeIndex } from "../recording/observation-capture";
+import { RecordingObservationSession } from "../recording/observation-session";
+import { RecordingStateRegistry } from "../recording/state-registry";
+import { buildTraceV3 } from "../recording/trace-builder-v3";
+import type { RecordingDraftStep } from "../recording/types";
+
+const URL = "https://example.com/login";
+
+function sessionWithInput(redactValues = false): RecordingObservationSession {
+  const session = new RecordingObservationSession({ redactValues });
+  const state = session.registry.register({
+    url: URL,
+    vomText: '@vom 1\ntextbox "Password" value="••••••" [ref=e1]',
+  });
+  session.cursor.lastSettled = {
+    stateId: state.id,
+    rootFrameId: "root",
+    index: new ObservationNodeIndex({
+      rootFrameId: "root",
+      matchNodes: [
+        {
+          frameId: "root",
+          backendNodeId: 42,
+          tag: "input",
+          rect: { x: 20, y: 40, w: 200, h: 30 },
+          localRect: { x: 20, y: 40, w: 200, h: 30 },
+        },
+      ],
+      refs: [{ ref: "e1", backendNodeId: 42, role: "textbox", name: "Password", line: 1 }],
+    }),
+    url: URL,
+  };
+  return session;
+}
+
+function finalizedFillTrace(value: string, redactValues: boolean) {
+  const session = sessionWithInput(redactValues);
+  const draft: RecordingDraftStep = {
+    op: "fill",
+    captureTarget: { tag: "input", role: "textbox", name: "Password" },
+    value,
+    targetHint: {
+      geometry: { rect: { x: 20, y: 40, w: 200, h: 30 }, tag: "input" },
+    },
+  };
+  session.bindDraft(draft, 1);
+  draft.postStateId = draft.preStateId;
+  return buildTraceV3({
+    registry: session.registry,
+    drafts: [draft],
+    annotations: session.annotations,
+    startedAt: "2026-08-12T00:00:00.000Z",
+    stoppedBy: "user_finish",
+    bskVersion: "test",
+    redactValues,
+  });
+}
+
+function finalizedFillBody(value: string, redactValues: boolean): string {
+  return finalizedFillTrace(value, redactValues).states[0]!.body;
+}
+
+describe("record observation annotations", () => {
+  it("omits a fill literal when values are redacted", () => {
+    const secret = "hunter2-private";
+    const dumped = JSON.stringify(finalizedFillTrace(secret, true));
+    expect(dumped).toContain("step 1: fill");
+    expect(dumped).not.toContain(secret);
+  });
+
+  it("keeps ordinary fill details", () => {
+    expect(finalizedFillBody("ordinary text", false)).toContain('step 1: fill: "ordinary text"');
+  });
+
+  it("encodes title and URL so line breaks cannot corrupt state metadata", () => {
+    const registry = new RecordingStateRegistry();
+    const state = registry.register({
+      url: "https://example.com/a\nb",
+      title: "hello\nworld",
+      vomText: "@vom 1",
+    });
+    const trace = buildTraceV3({
+      registry,
+      drafts: [{ op: "scroll", preStateId: state.id, postStateId: state.id }],
+      startedAt: "2026-08-12T00:00:00.000Z",
+      stoppedBy: "user_finish",
+      bskVersion: "test",
+    });
+    expect(trace.states[0]?.body).toContain('url: "https://example.com/a\\nb"');
+    expect(trace.states[0]?.body).toContain('title: "hello\\nworld"');
+  });
+});
+
+describe("recording state ownership", () => {
+  it("deduplicates within one recording and isolates ids between recordings", () => {
+    const first = new RecordingStateRegistry();
+    const second = new RecordingStateRegistry();
+    expect(first.register({ url: URL, vomText: "same" }).id).toBe("s1");
+    expect(first.register({ url: URL, vomText: "same" }).id).toBe("s1");
+    expect(second.register({ url: URL, vomText: "other" }).id).toBe("s1");
+  });
+
+  it("enriches metadata when a deduplicated observation becomes more complete", () => {
+    const registry = new RecordingStateRegistry();
+    registry.register({ url: URL, vomText: "same" });
+    const state = registry.register({
+      url: URL,
+      title: "Login",
+      vomText: "same",
+      truncated: true,
+    });
+    expect(state).toMatchObject({ id: "s1", title: "Login", truncated: true });
+  });
+});
+
+describe("draft binding", () => {
+  it("keeps capture semantics when no observation exists", () => {
+    const session = new RecordingObservationSession();
+    const draft: RecordingDraftStep = {
+      op: "hover",
+      captureTarget: { tag: "button", role: "button", name: "新建" },
+    };
+    session.bindDraft(draft, 1);
+    expect(draft.matchedTarget).toEqual({ role: "button", name: "新建", unmatched: true });
+    expect(draft.preStateId).toBeUndefined();
+  });
+
+  it("does not bind an unmatched new action to a stale observation", () => {
+    const session = sessionWithInput();
+    const draft: RecordingDraftStep = {
+      op: "click",
+      captureTarget: { tag: "button", role: "button", name: "Confirm" },
+      targetHint: {
+        geometry: { rect: { x: 400, y: 300, w: 80, h: 30 }, tag: "button" },
+      },
+    };
+    session.bindDraft(draft, 2, true);
+    expect(draft.preStateId).toBeUndefined();
+    expect("matchedTarget" in draft ? draft.matchedTarget : undefined).toEqual({
+      role: "button",
+      name: "Confirm",
+      unmatched: true,
+    });
+  });
+});
@@ -0,0 +1,289 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+
+const captureRecordingObservation = vi.hoisted(() => vi.fn());
+const waitForDocumentSettled = vi.hoisted(() => vi.fn(async () => "quiet" as const));
+
+vi.mock("../recording/observation-capture", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../recording/observation-capture")>();
+  return { ...actual, captureRecordingObservation };
+});
+
+vi.mock("../recording/document-settle", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../recording/document-settle")>();
+  return { ...actual, waitForDocumentSettled };
+});
+
+import { ObservationNodeIndex } from "../recording/observation-capture";
+import { RecordingObservationRuntime } from "../recording/recording-runtime";
+import type { RecordingDraftStep } from "../recording/types";
+
+function observation(url = "https://example.com/") {
+  return {
+    rootFrameId: "root",
+    index: new ObservationNodeIndex({ rootFrameId: "root", matchNodes: [], refs: [] }),
+    url,
+    title: "Example",
+    vomText: '@vom 1\nRootWebArea "Example"',
+    truncated: false,
+  };
+}
+
+function runtime(): RecordingObservationRuntime {
+  return new RecordingObservationRuntime({
+    cdp: { send: vi.fn() as unknown as CdpRunner["send"] },
+    tabsApi: { get: vi.fn(), query: vi.fn() } as unknown as ChromeTabsApi,
+  });
+}
+
+describe("RecordingObservationRuntime", () => {
+  afterEach(() => {
+    captureRecordingObservation.mockReset();
+    waitForDocumentSettled.mockClear();
+  });
+
+  it("shares one initial capture and includes it in flush", async () => {
+    let release!: (value: ReturnType<typeof observation>) => void;
+    captureRecordingObservation.mockReturnValueOnce(
+      new Promise((resolve) => {
+        release = resolve;
+      }),
+    );
+    const recording = runtime();
+
+    const first = recording.captureInitial(7);
+    const second = recording.captureInitial(7);
+    const flushed = recording.flush();
+    let flushCompleted = false;
+    void flushed.then(() => {
+      flushCompleted = true;
+    });
+
+    await Promise.resolve();
+    expect(captureRecordingObservation).toHaveBeenCalledTimes(1);
+    expect(flushCompleted).toBe(false);
+
+    release(observation());
+    await Promise.all([first, second, flushed]);
+    expect(flushCompleted).toBe(true);
+  });
+
+  it("cancels an in-flight initial capture", async () => {
+    captureRecordingObservation.mockImplementationOnce(
+      (input: { signal?: AbortSignal }) =>
+        new Promise((_, reject) => {
+          input.signal?.addEventListener(
+            "abort",
+            () => reject(new DOMException("observation aborted", "AbortError")),
+            { once: true },
+          );
+        }),
+    );
+    const recording = runtime();
+
+    const pending = recording.captureInitial(7);
+    recording.cancel();
+
+    await expect(pending).rejects.toMatchObject({ name: "AbortError" });
+  });
+
+  it("retries a failed initial capture when the recording settles at stop", async () => {
+    captureRecordingObservation
+      .mockRejectedValueOnce(new Error("document swapped"))
+      .mockResolvedValueOnce(observation());
+    const recording = runtime();
+
+    await expect(recording.captureInitial(7)).rejects.toThrow("document swapped");
+    await recording.settleTrailing(7, []);
+    const trace = recording.buildTrace({
+      drafts: [],
+      startedAt: "2026-08-19T00:00:00.000Z",
+      stoppedBy: "user_finish",
+      bskVersion: "0.1.6",
+    });
+
+    expect(captureRecordingObservation).toHaveBeenCalledTimes(2);
+    expect(trace.states).toHaveLength(1);
+  });
+
+  it("keeps runtime matching data out of the serialized trace", async () => {
+    const captured = observation();
+    captured.index = new ObservationNodeIndex({
+      rootFrameId: "root",
+      matchNodes: [
+        {
+          frameId: "root",
+          backendNodeId: 42,
+          tag: "button",
+          rect: { x: 10, y: 20, w: 100, h: 30 },
+          localRect: { x: 10, y: 20, w: 100, h: 30 },
+        },
+      ],
+      refs: [{ ref: "e1", backendNodeId: 42, role: "button", name: "Submit", line: 1 }],
+    });
+    captureRecordingObservation.mockResolvedValueOnce(captured);
+    const recording = runtime();
+
+    await recording.captureInitial(7);
+    const dumped = JSON.stringify(
+      recording.buildTrace({
+        drafts: [],
+        startedAt: "2026-08-19T00:00:00.000Z",
+        stoppedBy: "user_finish",
+        bskVersion: "0.1.6",
+      }),
+    );
+
+    expect(dumped).toContain("RootWebArea");
+    expect(dumped).not.toContain("matchNodes");
+    expect(dumped).not.toContain("localRect");
+    expect(dumped).not.toContain("backendNodeId");
+    expect(dumped).not.toContain("ObservationNodeIndex");
+  });
+
+  it("captures a tab transition without sharing observation cursors", async () => {
+    captureRecordingObservation
+      .mockResolvedValueOnce(observation("https://example.com/first"))
+      .mockResolvedValueOnce(observation("https://example.com/second"));
+    const recording = runtime();
+
+    await recording.captureInitial(4);
+    const transition = await recording.captureTabTransition(4, 5);
+    await recording.captureInitial(4);
+    await recording.captureInitial(5);
+
+    expect(transition).toEqual({
+      preStateId: "s1",
+      postStateId: "s2",
+      targetUrl: "https://example.com/second",
+    });
+    expect(captureRecordingObservation.mock.calls.map(([input]) => input.tabId)).toEqual([4, 5]);
+  });
+
+  it("binds an iframe draft to its marked CDP Document scope", async () => {
+    captureRecordingObservation.mockResolvedValueOnce({
+      ...observation(),
+      index: new ObservationNodeIndex({
+        rootFrameId: "root",
+        frames: [
+          {
+            frameId: "child",
+            target: { tabId: 7, sessionId: "oopif-session" },
+            recordingDocumentId: "producer-1",
+          },
+        ],
+        matchNodes: [
+          {
+            backendNodeId: 42,
+            frameId: "child",
+            tag: "button",
+            rect: { x: 410, y: 20, w: 100, h: 30 },
+            localRect: { x: 10, y: 20, w: 100, h: 30 },
+          },
+        ],
+        refs: [{ ref: "e1", backendNodeId: 42, frameId: "child", line: 1 }],
+      }),
+    });
+    const recording = runtime();
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "click" as const,
+        captureTarget: { tag: "button", role: "button", name: "Save" },
+        targetHint: {
+          geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+        },
+      },
+    ];
+
+    await recording.captureInitial(7);
+    await recording.processDraft(7, drafts, 0, "producer-1");
+    recording.cancel();
+
+    const draft = drafts[0];
+    expect(draft?.op).toBe("click");
+    if (!draft || draft.op !== "click") throw new Error("expected click draft");
+    expect(draft.targetHint).toMatchObject({
+      frameId: "child",
+      geometrySpace: "local",
+    });
+    expect(draft.matchedTarget?.ref).toBe("e1");
+  });
+
+  it("refreshes a late iframe before matching its first action", async () => {
+    const iframeObservation = {
+      ...observation(),
+      index: new ObservationNodeIndex({
+        rootFrameId: "root",
+        frames: [
+          {
+            frameId: "child",
+            target: { tabId: 7, sessionId: "oopif-session" },
+            recordingDocumentId: "producer-1",
+          },
+        ],
+        matchNodes: [
+          {
+            backendNodeId: 42,
+            frameId: "child",
+            tag: "button",
+            rect: { x: 410, y: 20, w: 100, h: 30 },
+            localRect: { x: 10, y: 20, w: 100, h: 30 },
+          },
+        ],
+        refs: [
+          {
+            ref: "e1",
+            backendNodeId: 42,
+            frameId: "child",
+            role: "button",
+            name: "表格视图",
+            line: 1,
+          },
+        ],
+      }),
+    };
+    captureRecordingObservation
+      .mockResolvedValueOnce(observation())
+      .mockResolvedValueOnce(iframeObservation)
+      .mockResolvedValueOnce(iframeObservation);
+    const recording = runtime();
+
+    await recording.captureInitial(7);
+    await recording.refreshDocument(7, "producer-1");
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "click",
+        captureTarget: { tag: "button", role: "button", name: "表格视图" },
+        targetHint: {
+          geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+        },
+      },
+    ];
+    await recording.processDraft(7, drafts, 0, "producer-1");
+    recording.cancel();
+
+    expect(captureRecordingObservation).toHaveBeenCalledTimes(3);
+    expect(waitForDocumentSettled).toHaveBeenCalledWith(
+      expect.anything(),
+      { frameId: "child", target: { tabId: 7, sessionId: "oopif-session" } },
+      { signal: expect.any(AbortSignal) },
+    );
+    const draft = drafts[0];
+    expect(draft?.op).toBe("click");
+    if (!draft || draft.op !== "click") throw new Error("expected click draft");
+    expect(draft.matchedTarget).toMatchObject({ ref: "e1", name: "表格视图" });
+  });
+
+  it("does not poison final flush when a frame readiness refresh fails", async () => {
+    captureRecordingObservation
+      .mockResolvedValueOnce(observation())
+      .mockRejectedValueOnce(new Error("child Document replaced"));
+    const recording = runtime();
+
+    await recording.captureInitial(7);
+    await expect(recording.refreshDocument(7, "producer-1")).rejects.toThrow(
+      "child Document replaced",
+    );
+    await expect(recording.flush()).resolves.toBeUndefined();
+  });
+});
@@ -1,80 +0,0 @@
-import { describe, expect, it } from "vitest";
-import { appendRecordedPayload, observeRecordedNavigation } from "../recording-step-buffer";
-
-describe("recording-step-buffer", () => {
-  it("stores semantic click without summary", () => {
-    const buffer = { steps: [], pendingNavigation: false };
-    appendRecordedPayload(buffer, {
-      op: "click",
-      target: { tag: "button", role: "button", name: "发布" },
-      expects_navigation: true,
-    });
-    expect(buffer.steps).toEqual([
-      {
-        op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
-      },
-    ]);
-    expect(buffer.pendingNavigation).toBe(true);
-  });
-
-  it("annotates navigated_to on action-caused navigation instead of wait_for_navigation", () => {
-    const buffer = {
-      steps: [
-        {
-          op: "click" as const,
-          target: { tag: "button", role: "button", name: "发布" },
-        },
-      ],
-      currentUrl: "https://example.com/a",
-      pendingNavigation: true,
-      pendingNavigationDeadline: Date.now() + 5_000,
-    };
-    observeRecordedNavigation(buffer, "https://example.com/b", true);
-    expect(buffer.steps).toEqual([
-      {
-        op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
-        navigated_to: "https://example.com/b",
-      },
-    ]);
-    expect(JSON.stringify(buffer.steps)).not.toContain("wait_for_navigation");
-  });
-
-  it("annotates navigated_to onto a select that auto-submits a navigation", () => {
-    const buffer = {
-      steps: [
-        {
-          op: "select" as const,
-          target: { tag: "select", role: "combobox", name: "分类" },
-          values: ["tech"],
-        },
-      ],
-      currentUrl: "https://example.com/list",
-      pendingNavigation: true,
-      pendingNavigationDeadline: Date.now() + 5_000,
-    };
-    observeRecordedNavigation(buffer, "https://example.com/list?cat=tech", true);
-    expect(buffer.steps).toEqual([
-      {
-        op: "select",
-        target: { tag: "select", role: "combobox", name: "分类" },
-        values: ["tech"],
-        navigated_to: "https://example.com/list?cat=tech",
-      },
-    ]);
-  });
-
-  it("emits navigate for uncaused URL changes", () => {
-    const buffer = {
-      steps: [],
-      currentUrl: "https://example.com/a",
-      pendingNavigation: false,
-    };
-    observeRecordedNavigation(buffer, "https://example.com/b", false);
-    expect(buffer.steps[0]).toMatchObject({
-      op: "navigate",
-      url: "https://example.com/b",
-    });
-  });
-});
@@ -0,0 +1,136 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import { ObservationNodeIndex, type RegisteredObservation } from "../recording/observation-capture";
+import { RecordingObservationSession } from "../recording/observation-session";
+import { SettleController } from "../recording/settle-controller";
+import type { RecordingDraftStep } from "../recording/types";
+
+const OBSERVATION: RegisteredObservation = {
+  stateId: "s-next",
+  rootFrameId: "root",
+  index: new ObservationNodeIndex({ rootFrameId: "root", matchNodes: [], refs: [] }),
+  url: "https://example.com/next",
+};
+
+describe("SettleController", () => {
+  afterEach(() => vi.useRealTimers());
+
+  it("aborts superseded capture work and lands the prior action on the next origin", async () => {
+    vi.useFakeTimers();
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({
+        result: { value: { idleMs: 1_000, readyState: "complete" } },
+      })) as unknown as CdpRunner["send"],
+    };
+    const tabsApi: ChromeTabsApi = {
+      get: vi.fn(async () => ({ id: 7, url: OBSERVATION.url }) as chrome.tabs.Tab),
+      query: vi.fn(async () => []),
+    };
+    const session = new RecordingObservationSession();
+    let firstSignal: AbortSignal | undefined;
+    vi.spyOn(session, "capture")
+      .mockImplementationOnce(async (_cdp, _tabs, _tabId, signal) => {
+        firstSignal = signal;
+        return new Promise<RegisteredObservation>((_resolve, reject) => {
+          signal?.addEventListener(
+            "abort",
+            () => reject(new DOMException("observation aborted", "AbortError")),
+            { once: true },
+          );
+        });
+      })
+      .mockResolvedValueOnce(OBSERVATION);
+
+    const drafts: RecordingDraftStep[] = [
+      { op: "click", captureTarget: { tag: "button", name: "First" }, preStateId: "s1" },
+    ];
+    const controller = new SettleController({ session, cdp, tabsApi, tabId: 7 });
+    controller.schedule(drafts, 0);
+    await vi.advanceTimersByTimeAsync(180);
+
+    drafts.push({
+      op: "click",
+      captureTarget: { tag: "button", name: "Second" },
+      preStateId: "s-next",
+    });
+    controller.schedule(drafts, 1);
+    expect(firstSignal?.aborted).toBe(true);
+    expect(drafts[0]?.postStateId).toBe("s-next");
+
+    await vi.advanceTimersByTimeAsync(500);
+    await controller.flush();
+    expect(drafts[1]?.postStateId).toBe("s-next");
+  });
+
+  it("does not consume a newer redirect while reading the prior landing URL", async () => {
+    vi.useFakeTimers();
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({
+        result: { value: { idleMs: 1_000, readyState: "complete" } },
+      })) as unknown as CdpRunner["send"],
+    };
+    let resolveFirstTab!: (tab: chrome.tabs.Tab) => void;
+    const firstTab = new Promise<chrome.tabs.Tab>((resolve) => {
+      resolveFirstTab = resolve;
+    });
+    const tabsApi: ChromeTabsApi = {
+      get: vi
+        .fn()
+        .mockImplementationOnce(() => firstTab)
+        .mockResolvedValue({ id: 7, url: OBSERVATION.url }),
+      query: vi.fn(async () => []),
+    };
+    const session = new RecordingObservationSession();
+    session.cursor.lastSettled = OBSERVATION;
+    const drafts: RecordingDraftStep[] = [];
+    const controller = new SettleController({ session, cdp, tabsApi, tabId: 7 });
+
+    controller.scheduleRedirect(drafts, "https://example.com/intermediate");
+    await vi.advanceTimersByTimeAsync(180);
+    expect(tabsApi.get).toHaveBeenCalledTimes(1);
+
+    controller.scheduleRedirect(drafts, OBSERVATION.url);
+    resolveFirstTab({ id: 7, url: "https://example.com/intermediate" } as chrome.tabs.Tab);
+    await vi.advanceTimersByTimeAsync(500);
+    await controller.flushRedirects();
+
+    expect(drafts).toEqual([]);
+    expect(controller.hasPending).toBe(false);
+  });
+
+  it("settles an action in its own OOPIF document scope", async () => {
+    vi.useFakeTimers();
+    const send = vi.fn();
+    const sendToTarget = vi.fn(async (_target, method: string) => {
+      if (method === "Page.createIsolatedWorld") return { executionContextId: 39 };
+      return { result: { value: { idleMs: 1_000, readyState: "complete" } } };
+    });
+    const cdp: CdpRunner = {
+      send: send as unknown as CdpRunner["send"],
+      sendToTarget: sendToTarget as unknown as NonNullable<CdpRunner["sendToTarget"]>,
+    };
+    const tabsApi: ChromeTabsApi = {
+      get: vi.fn(async () => ({ id: 7, url: OBSERVATION.url }) as chrome.tabs.Tab),
+      query: vi.fn(async () => []),
+    };
+    const session = new RecordingObservationSession();
+    vi.spyOn(session, "capture").mockResolvedValue(OBSERVATION);
+    const drafts: RecordingDraftStep[] = [
+      { op: "click", captureTarget: { tag: "button", name: "Inside frame" } },
+    ];
+    const controller = new SettleController({ session, cdp, tabsApi, tabId: 7 });
+    const target = { tabId: 7, sessionId: "oopif-session" };
+
+    controller.schedule(drafts, 0, { target, frameId: "oopif-frame" });
+    await vi.advanceTimersByTimeAsync(180);
+    await controller.flush();
+
+    expect(send).not.toHaveBeenCalled();
+    expect(sendToTarget).toHaveBeenCalledWith(
+      target,
+      "Runtime.evaluate",
+      expect.objectContaining({ contextId: 39 }),
+    );
+    expect(drafts[0]?.postStateId).toBe("s-next");
+  });
+});
@@ -0,0 +1,164 @@
+import { describe, expect, it } from "vitest";
+import { appendRecordedPayload, observeRecordedNavigation } from "../recording/step-buffer";
+
+describe("recording-step-buffer", () => {
+  it("stores semantic click without summary", () => {
+    const buffer = { steps: [], navigation: { pendingNavigation: false } };
+    appendRecordedPayload(buffer, {
+      op: "click",
+      target: { tag: "button", role: "button", name: "发布" },
+      expects_navigation: true,
+    });
+    expect(buffer.steps).toEqual([
+      {
+        op: "click",
+        captureTarget: { tag: "button", role: "button", name: "发布" },
+      },
+    ]);
+    expect(buffer.navigation.pendingNavigation).toBe(true);
+  });
+
+  it("keeps the hovered element description as a capture fallback", () => {
+    const buffer = { steps: [], navigation: { pendingNavigation: false } };
+    appendRecordedPayload(
+      buffer,
+      {
+        op: "hover",
+        target: { tag: "button", role: "button", name: "新建" },
+        geometry: {
+          rect: { x: 900, y: 8, w: 60, h: 32 },
+          tag: "button",
+        },
+      },
+      {
+        geometry: {
+          rect: { x: 900, y: 8, w: 60, h: 32 },
+          tag: "button",
+        },
+      },
+    );
+    expect(buffer.steps).toEqual([
+      {
+        op: "hover",
+        captureTarget: { tag: "button", role: "button", name: "新建" },
+        targetHint: {
+          geometry: {
+            rect: { x: 900, y: 8, w: 60, h: 32 },
+            tag: "button",
+          },
+        },
+      },
+    ]);
+  });
+
+  it("annotates navigated_to on action-caused navigation instead of wait_for_navigation", () => {
+    const buffer = {
+      steps: [
+        {
+          op: "click" as const,
+          captureTarget: { tag: "button", role: "button", name: "发布" },
+        },
+      ],
+      navigation: {
+        currentUrl: "https://example.com/a",
+        pendingNavigation: true,
+        pendingNavigationDeadline: Date.now() + 5_000,
+      },
+    };
+    observeRecordedNavigation(buffer, "https://example.com/b", true);
+    expect(buffer.steps).toEqual([
+      {
+        op: "click",
+        captureTarget: { tag: "button", role: "button", name: "发布" },
+        navigatedTo: "https://example.com/b",
+      },
+    ]);
+    expect(JSON.stringify(buffer.steps)).not.toContain("wait_for_navigation");
+  });
+
+  it("annotates navigated_to onto a select that auto-submits a navigation", () => {
+    const buffer = {
+      steps: [
+        {
+          op: "select" as const,
+          captureTarget: { tag: "select", role: "combobox", name: "分类" },
+          values: ["tech"],
+        },
+      ],
+      navigation: {
+        currentUrl: "https://example.com/list",
+        pendingNavigation: true,
+        pendingNavigationDeadline: Date.now() + 5_000,
+      },
+    };
+    observeRecordedNavigation(buffer, "https://example.com/list?cat=tech", true);
+    expect(buffer.steps).toEqual([
+      {
+        op: "select",
+        captureTarget: { tag: "select", role: "combobox", name: "分类" },
+        values: ["tech"],
+        navigatedTo: "https://example.com/list?cat=tech",
+      },
+    ]);
+  });
+
+  it("emits navigate for uncaused URL changes", () => {
+    const buffer = {
+      steps: [],
+      navigation: { currentUrl: "https://example.com/a", pendingNavigation: false },
+    };
+    const result = observeRecordedNavigation(buffer, "https://example.com/b", false);
+    expect(result).toEqual({ kind: "appended", index: 0 });
+    expect(buffer.steps[0]).toMatchObject({
+      op: "navigate",
+      url: "https://example.com/b",
+    });
+  });
+
+  it("asks the recorder to coalesce redirect hops instead of emitting each one", () => {
+    const buffer = {
+      steps: [],
+      navigation: {
+        currentUrl: "https://passport.example/login",
+        pendingNavigation: false,
+      },
+    };
+    const hop1 = observeRecordedNavigation(
+      buffer,
+      "https://passport.example/callback",
+      false,
+      "link",
+      ["server_redirect"],
+    );
+    expect(hop1).toEqual({
+      kind: "coalesce_redirect",
+      url: "https://passport.example/callback",
+    });
+    expect(buffer.steps).toEqual([]);
+
+    const hop2 = observeRecordedNavigation(buffer, "https://app.example/dashboard", false, "link", [
+      "client_redirect",
+    ]);
+    expect(hop2).toEqual({
+      kind: "coalesce_redirect",
+      url: "https://app.example/dashboard",
+    });
+    expect(buffer.steps).toEqual([]);
+    expect(buffer.navigation.currentUrl).toBe("https://app.example/dashboard");
+  });
+
+  it("does not reuse redirect metadata for a later content-observed URL change", () => {
+    const buffer = {
+      steps: [],
+      navigation: {
+        currentUrl: "https://example.com/redirect",
+        pendingNavigation: false,
+      },
+    };
+
+    const result = observeRecordedNavigation(buffer, "https://example.com/spa");
+
+    expect(result).toEqual({ kind: "appended", index: 0 });
+    expect(buffer.steps[0]).toMatchObject({ op: "navigate", url: "https://example.com/spa" });
+  });
+});
@@ -0,0 +1,39 @@
+import { describe, expect, it } from "vitest";
+import { RecordingTabCoordinator } from "../recording/tab-coordinator";
+
+describe("RecordingTabCoordinator", () => {
+  it("keeps navigation state isolated per tab", () => {
+    const tabs = new RecordingTabCoordinator(4, "https://example.com/first");
+    const first = tabs.navigation(4);
+    first.pendingNavigation = true;
+    const second = tabs.navigation(5, "https://example.com/second");
+
+    expect(second).toEqual({
+      currentUrl: "https://example.com/second",
+      pendingNavigation: false,
+    });
+    expect(tabs.navigation(4)).toBe(first);
+    expect(tabs.navigation(4).pendingNavigation).toBe(true);
+  });
+
+  it("invalidates an earlier activation when a newer tab becomes active", () => {
+    const tabs = new RecordingTabCoordinator(4);
+    const second = tabs.noteActivation(5);
+    const third = tabs.noteActivation(6);
+
+    expect(tabs.isLatest(second)).toBe(false);
+    expect(tabs.isLatest(third)).toBe(true);
+    tabs.commit(6);
+    expect(tabs.currentTabId).toBe(6);
+  });
+
+  it("commits the freshly observed URL when returning to an existing tab", () => {
+    const tabs = new RecordingTabCoordinator(4);
+    tabs.navigation(5, "https://example.com/old");
+
+    tabs.commit(5, "https://example.com/new");
+
+    expect(tabs.currentTabId).toBe(5);
+    expect(tabs.navigation(5).currentUrl).toBe("https://example.com/new");
+  });
+});
@@ -0,0 +1,159 @@
+import type { RenderedRef } from "@browser-skill/vom";
+import { describe, expect, it } from "vitest";
+import type { CaptureVomMatchNode } from "@/tools/capture-vom-observation";
+import { ObservationNodeIndex, type RegisteredObservation } from "../recording/observation-capture";
+import { matchObservationTarget } from "../recording/target-matcher";
+
+function node(backendNodeId: number, frameId: string, x = 10): CaptureVomMatchNode {
+  return {
+    backendNodeId,
+    frameId,
+    tag: "button",
+    rect: { x, y: 20, w: 100, h: 30 },
+    localRect: { x, y: 20, w: 100, h: 30 },
+  };
+}
+
+function observation(
+  matchNodes: CaptureVomMatchNode[],
+  refs: RenderedRef[],
+): RegisteredObservation {
+  return {
+    stateId: "s1",
+    rootFrameId: "root",
+    index: new ObservationNodeIndex({ rootFrameId: "root", matchNodes, refs }),
+    url: "https://example.com",
+  };
+}
+
+describe("matchObservationTarget", () => {
+  it("indexes the safe geometry DTO without discarding frame-local geometry", () => {
+    const geometry = node(42, "child");
+    geometry.localRect = { x: 5, y: 6, w: 100, h: 30 };
+    const ref: RenderedRef = {
+      ref: "e1",
+      backendNodeId: 42,
+      frameId: "child",
+      line: 1,
+    };
+    const candidate = observation([geometry], [ref]).index.candidates("child", "button")[0];
+
+    expect(candidate).toEqual({ frameId: "child", geometry, ref });
+  });
+
+  it("matches a unique node using canonical top-level viewport geometry", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root")],
+        [{ ref: "e1", backendNodeId: 42, role: "button", name: "发布", line: 1 }],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+    });
+    expect(target).toEqual({ ref: "e1", role: "button", name: "发布" });
+  });
+
+  it("uses frame id with backend node id so sibling frames cannot collide", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "left"), node(42, "right")],
+        [
+          { ref: "e1", backendNodeId: 42, frameId: "left", line: 1 },
+          { ref: "e2", backendNodeId: 42, frameId: "right", line: 2 },
+        ],
+      ),
+      hint: {
+        frameId: "right",
+        geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+      },
+    });
+    expect(target.ref).toBe("e2");
+  });
+
+  it("matches iframe capture geometry in the child viewport coordinate space", () => {
+    const child = node(42, "child", 410);
+    child.localRect = { x: 10, y: 20, w: 100, h: 30 };
+    const target = matchObservationTarget({
+      observation: observation(
+        [child],
+        [{ ref: "e1", backendNodeId: 42, frameId: "child", line: 1 }],
+      ),
+      hint: {
+        frameId: "child",
+        geometrySpace: "local",
+        geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+      },
+    });
+    expect(target.ref).toBe("e1");
+  });
+
+  it("restricts a missing frame hint to the root frame", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "child")],
+        [{ ref: "e1", backendNodeId: 42, frameId: "child", line: 1 }],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+      fallback: { tag: "button", name: "发布" },
+    });
+    expect(target).toEqual({ name: "发布", unmatched: true });
+  });
+
+  it("fails closed when the source Document has no VOM frame mapping", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root")],
+        [{ ref: "e1", backendNodeId: 42, role: "button", name: "发布", line: 1 }],
+      ),
+      hint: {
+        frameId: null,
+        geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" },
+      },
+      fallback: { tag: "button", role: "button", name: "发布" },
+    });
+    expect(target).toEqual({ role: "button", name: "发布", unmatched: true });
+  });
+
+  it("returns unmatched for ambiguous geometry", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root"), node(43, "root")],
+        [
+          { ref: "e1", backendNodeId: 42, line: 1 },
+          { ref: "e2", backendNodeId: 43, line: 2 },
+        ],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+    });
+    expect(target.unmatched).toBe(true);
+  });
+
+  it("uses semantics when geometry is unavailable without crossing frame boundaries", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(41, "root"), node(42, "child")],
+        [
+          { ref: "e1", backendNodeId: 41, role: "button", name: "保存", line: 1 },
+          { ref: "e2", backendNodeId: 42, frameId: "child", role: "button", name: "保存", line: 2 },
+        ],
+      ),
+      hint: { frameId: "child" },
+      fallback: { tag: "button", role: "button", name: "保存" },
+    });
+    expect(target.ref).toBe("e2");
+  });
+
+  it("uses semantics to disambiguate equal geometry in one frame", () => {
+    const target = matchObservationTarget({
+      observation: observation(
+        [node(42, "root"), node(43, "root")],
+        [
+          { ref: "e1", backendNodeId: 42, role: "button", name: "保存", line: 1 },
+          { ref: "e2", backendNodeId: 43, role: "button", name: "取消", line: 2 },
+        ],
+      ),
+      hint: { geometry: { rect: { x: 10, y: 20, w: 100, h: 30 }, tag: "button" } },
+      fallback: { tag: "button", role: "button", name: "取消" },
+    });
+    expect(target.ref).toBe("e2");
+  });
+});
@@ -1,6 +1,15 @@
 import { describe, expect, it } from "vitest";
-import type { DraftTraceStep } from "@/transport/types";
-import { reduceTraceSteps, resolveTraceStartUrl, shouldRecordPress } from "../trace-reducer";
+import type { RecordingDraftStep } from "@/lib/recording/types";
+import { shouldRecordPress } from "../recording/draft-policy";
+import { buildTraceV2 } from "../recording/trace-reducer-v2";
+
+function reduceTraceSteps(steps: RecordingDraftStep[], startUrl?: string) {
+  return buildTraceV2({
+    steps,
+    startedAt: "2026-01-01T00:00:00.000Z",
+    ...(startUrl ? { startUrl } : {}),
+  });
+}

 describe("shouldRecordPress", () => {
  it("keeps Enter and Escape", () => {
@@ -18,36 +27,47 @@ describe("shouldRecordPress", () => {
 });

 describe("reduceTraceSteps", () => {
+  it("does not expose internal tab transitions in trace v2", () => {
+    const trace = reduceTraceSteps([
+      {
+        op: "switch_tab",
+        preStateId: "s1",
+        postStateId: "s2",
+      },
+    ]);
+    expect(trace.steps).toEqual([]);
+  });
+
  it("builds steps with pages dictionary and page id references", () => {
-    const drafts: DraftTraceStep[] = [
+    const drafts: RecordingDraftStep[] = [
      {
        op: "navigate",
        url: "https://example.com/search?q=hello&utm_source=x",
-        page_url: "https://example.com/search?q=hello&utm_source=x",
+        pageUrl: "https://example.com/search?q=hello&utm_source=x",
      },
      {
        op: "fill",
-        target: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
+        captureTarget: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
        value: "browser skill",
-        page_url: "https://example.com/search?q=hello&utm_source=x",
+        pageUrl: "https://example.com/search?q=hello&utm_source=x",
      },
      {
        op: "press",
        key: "Enter",
-        target: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
-        navigated_to: "https://example.com/results/42",
-        page_url: "https://example.com/search?q=hello&utm_source=x",
+        captureTarget: { tag: "input", role: "textbox", name: "搜索", name_attr: "q" },
+        navigatedTo: "https://example.com/results/42",
+        pageUrl: "https://example.com/search?q=hello&utm_source=x",
      },
      {
        op: "click",
-        target: { tag: "button", role: "button", name: "发布" },
-        navigated_to: "https://example.com/p/99",
-        page_url: "https://example.com/results/42",
+        captureTarget: { tag: "button", role: "button", name: "发布" },
+        navigatedTo: "https://example.com/p/99",
+        pageUrl: "https://example.com/results/42",
      },
      {
        op: "press",
        key: "a",
-        page_url: "https://example.com/p/99",
+        pageUrl: "https://example.com/p/99",
      },
    ];

@@ -109,9 +129,9 @@ describe("reduceTraceSteps", () => {
      [
        {
          op: "fill",
-          target: { tag: "input", role: "textbox", name: "Search query" },
+          captureTarget: { tag: "input", role: "textbox", name: "Search query" },
          value: "",
-          page_url: "https://example.com/search",
+          pageUrl: "https://example.com/search",
        },
      ],
      "https://example.com/search",
@@ -125,16 +145,16 @@ describe("reduceTraceSteps", () => {
    ]);
  });

-  it("maps select navigated_to onto effect.navigated_to (page id)", () => {
+  it("maps select navigatedTo onto effect.navigatedTo (page id)", () => {
    const { pages, steps } = reduceTraceSteps(
      [
        {
          op: "select",
-          target: { tag: "select", role: "combobox", name: "分类" },
+          captureTarget: { tag: "select", role: "combobox", name: "分类" },
          values: ["tech"],
          labels: ["技术"],
-          navigated_to: "https://example.com/list?cat=tech",
-          page_url: "https://example.com/list",
+          navigatedTo: "https://example.com/list?cat=tech",
+          pageUrl: "https://example.com/list",
        },
      ],
      "https://example.com/list",
@@ -151,36 +171,32 @@ describe("reduceTraceSteps", () => {
    });
  });

-  it("keeps hover steps before menu clicks", () => {
+  it("drops hover steps, which only exist in trace v3", () => {
    const { steps } = reduceTraceSteps(
      [
        {
          op: "hover",
-          target: { tag: "span", role: "button", name: "Account" },
-          page_url: "https://example.com/app",
+          captureTarget: { tag: "span", role: "button", name: "Account" },
+          pageUrl: "https://example.com/app",
        },
        {
          op: "click",
-          target: { tag: "a", role: "link", name: "Profile" },
-          page_url: "https://example.com/app",
+          captureTarget: { tag: "a", role: "link", name: "Profile" },
+          pageUrl: "https://example.com/app",
        },
      ],
      "https://example.com/app",
    );
-    expect(steps.map((s) => s.op)).toEqual(["hover", "click"]);
-    expect(steps[0]).toMatchObject({
-      op: "hover",
-      page: "p1",
-      target: { name: "Account" },
-    });
+    expect(steps.map((s) => s.op)).toEqual(["click"]);
  });

  it("resolveTraceStartUrl prefers explicit start URL", () => {
    expect(
-      resolveTraceStartUrl(
-        [{ op: "navigate", url: "https://example.com/other" }],
-        "https://example.com/start",
-      ),
+      buildTraceV2({
+        steps: [{ op: "navigate", url: "https://example.com/other" }],
+        startedAt: "2026-01-01T00:00:00.000Z",
+        startUrl: "https://example.com/start",
+      }).entry.start_url,
    ).toBe("https://example.com/start");
  });
 });
@@ -0,0 +1,132 @@
+import { describe, expect, it } from "vitest";
+import { TRACE_VERSION_V3, VOM_FORMAT_VERSION } from "@/transport/types";
+import { RecordingStateRegistry } from "../recording/state-registry";
+import { buildTraceV3 } from "../recording/trace-builder-v3";
+import { reduceTraceStepsV3 } from "../recording/trace-reducer-v3";
+import type { RecordingDraftStep } from "../recording/types";
+
+describe("trace reducer v3", () => {
+  it("removes form literals when value redaction is requested", () => {
+    const reduced = reduceTraceStepsV3(
+      [
+        {
+          op: "fill",
+          value: "private@example.com",
+          preStateId: "s1",
+          postStateId: "s1",
+        },
+        {
+          op: "select",
+          values: ["private-account-id"],
+          labels: ["Private account"],
+          preStateId: "s1",
+          postStateId: "s1",
+        },
+      ],
+      { redactValues: true },
+    );
+
+    expect(reduced.steps[0]).toMatchObject({ op: "fill", value: "***", redacted: true });
+    expect(reduced.steps[1]).toMatchObject({ op: "select" });
+    expect(reduced.steps[1]).not.toHaveProperty("selection");
+    expect(JSON.stringify(reduced.steps)).not.toContain("private@example.com");
+    expect(JSON.stringify(reduced.steps)).not.toContain("private-account-id");
+  });
+
+  it("emits tab transitions only for callers that advertised support", () => {
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "switch_tab",
+        preStateId: "s1",
+        postStateId: "s2",
+      },
+    ];
+
+    expect(reduceTraceStepsV3(drafts).steps).toEqual([]);
+    expect(reduceTraceStepsV3(drafts, { includeTabSwitches: true }).steps).toEqual([
+      { op: "switch_tab", id: 1, state: "s1", result: { state: "s2" } },
+    ]);
+  });
+
+  it("keeps hover steps before menu clicks", () => {
+    const drafts: RecordingDraftStep[] = [
+      {
+        op: "hover",
+        captureTarget: { tag: "span", role: "button", name: "Account" },
+        preStateId: "s1",
+        postStateId: "s1",
+      },
+      {
+        op: "click",
+        captureTarget: { tag: "a", role: "link", name: "Profile" },
+        preStateId: "s1",
+        postStateId: "s1",
+      },
+    ];
+
+    expect(reduceTraceStepsV3(drafts).steps.map((s) => s.op)).toEqual(["hover", "click"]);
+  });
+
+  it("does not export a tab transition without both observation endpoints", () => {
+    const sourceOnly: RecordingDraftStep = { op: "switch_tab", preStateId: "s1" };
+    const targetOnly: RecordingDraftStep = { op: "switch_tab", postStateId: "s2" };
+
+    expect(
+      reduceTraceStepsV3([sourceOnly, targetOnly], { includeTabSwitches: true }).steps,
+    ).toEqual([]);
+  });
+
+  it("collapses redirect hops while retaining draft-to-step identity", () => {
+    const drafts: RecordingDraftStep[] = [
+      { op: "navigate", url: "https://example.com/start", preStateId: "s1", postStateId: "s2" },
+      {
+        op: "navigate",
+        url: "https://example.com/final",
+        transitionQualifiers: ["server_redirect"],
+        preStateId: "s2",
+        postStateId: "s3",
+      },
+    ];
+    const before = structuredClone(drafts);
+    const reduced = reduceTraceStepsV3(drafts);
+
+    expect(drafts).toEqual(before);
+    expect(reduced.steps).toEqual([
+      expect.objectContaining({
+        id: 1,
+        op: "navigate",
+        state: "s1",
+        to: "https://example.com/final",
+        result: { state: "s3" },
+      }),
+    ]);
+    expect(reduced.stepIdByDraftId.get(1)).toBe(1);
+    expect(reduced.stepIdByDraftId.get(2)).toBe(1);
+  });
+
+  it("builds the wire model from protocol constants", () => {
+    const registry = new RecordingStateRegistry();
+    const state = registry.register({ url: "https://example.com", vomText: "@vom 1" });
+    const trace = buildTraceV3({
+      registry,
+      drafts: [
+        {
+          op: "click",
+          captureTarget: { tag: "button", role: "button", name: "Save" },
+          preStateId: state.id,
+          postStateId: state.id,
+        },
+      ],
+      startedAt: "2026-08-12T00:00:00.000Z",
+      stoppedBy: "user_finish",
+      bskVersion: "test",
+    });
+
+    expect(trace.version).toBe(TRACE_VERSION_V3);
+    expect(trace.recorder.vom).toBe(VOM_FORMAT_VERSION);
+    expect(trace.steps[0]).toMatchObject({
+      op: "click",
+      target: { role: "button", name: "Save", unmatched: true },
+    });
+  });
+});
@@ -1,9 +1,9 @@
 /**
- * Wire protocol and background-side helper for hiding the extension's
- * in-page overlay while a screenshot is captured, so captured frames only
- * contain the page itself.
+ * Wire protocol and background-side helper for temporarily excluding the
+ * extension's in-page overlay. Screenshots use it to avoid captured chrome;
+ * coordinate-driven native input uses it so Chrome hit-tests the page.
 *
- * The background wraps every capture in `withOverlaysHiddenForCapture`,
+ * The background wraps each bounded operation in `withExtensionOverlayHidden`,
 * which sends `begin` (the content script hides the overlay host and only
 * acks once the compositor has produced an overlay-free frame) and always
 * follows up with `end`, even when the capture throws. Tabs without the
@@ -46,7 +46,7 @@ const defaultSendToTab: CaptureSuppressSendToTab = (tabId, message) =>
 * (or any other `begin` failure) simply skips suppression — there is no
 * overlay to hide in that tab.
 */
-export async function withOverlaysHiddenForCapture<T>(
+export async function withExtensionOverlayHidden<T>(
  tabId: number,
  fn: () => Promise<T>,
  sendToTab: CaptureSuppressSendToTab = defaultSendToTab,
@@ -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;
@@ -3,7 +3,7 @@
 * service worker and a tab's content script.
 */

-import type { TargetDescriptor } from "./describe-target";
+import type { CaptureTargetDescriptor } from "./describe-target";

 export const RECORD_START = "bsk-record-start";
 export const RECORD_STEP = "bsk-record-step";
@@ -16,6 +16,10 @@ export interface RecordStartAck {
  ok: true;
 }

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

 export interface RecordQueryMessage {
@@ -42,7 +46,7 @@ export interface RecordStartMessage {

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

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

@@ -112,8 +129,27 @@ export function isRecordQueryMessage(msg: unknown): msg is RecordQueryMessage {
 export function isRecordStepMessage(msg: unknown): msg is RecordStepMessage {
  if (typeof msg !== "object" || msg === null) return false;
  const m = msg as Record<string, unknown>;
-  if (m.type !== RECORD_STEP || typeof m.requestId !== "string") return false;
+  if (
+    m.type !== RECORD_STEP ||
+    typeof m.requestId !== "string" ||
+    typeof m.producerId !== "string" ||
+    m.producerId.length === 0 ||
+    typeof m.sequence !== "number" ||
+    !Number.isSafeInteger(m.sequence) ||
+    m.sequence < 1
+  ) {
+    return false;
+  }
  const step = m.step;
  if (typeof step !== "object" || step === null) return false;
  return typeof (step as RecordStepPayload).op === "string";
 }
+
+export function isAcceptedRecordStepAck(
+  value: unknown,
+  sequence: number,
+): value is Extract<RecordStepAck, { ok: true }> {
+  if (typeof value !== "object" || value === null) return false;
+  const ack = value as Partial<RecordStepAck>;
+  return ack.ok === true && ack.sequence === sequence;
+}
@@ -1,136 +0,0 @@
-import type { DraftTraceStep } from "@/transport/types";
-import type { RecordStepPayload } from "./record-bridge";
-
-export interface RecordingStepBuffer {
-  steps: DraftTraceStep[];
-  currentUrl?: string;
-  pendingNavigation: boolean;
-  pendingNavigationDeadline?: number;
-}
-
-const NAVIGATION_TRIGGER_WINDOW_MS = 3_000;
-
-function toDraftStep(payload: RecordStepPayload): DraftTraceStep | null {
-  const pageUrl = payload.page_url;
-  switch (payload.op) {
-    case "click":
-      return payload.target
-        ? {
-            op: "click",
-            target: payload.target,
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "hover":
-      return payload.target
-        ? {
-            op: "hover",
-            target: payload.target,
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "fill":
-      return payload.target
-        ? {
-            op: "fill",
-            target: payload.target,
-            value: payload.value ?? "",
-            ...(payload.redacted ? { redacted: true } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "press":
-      return payload.key
-        ? {
-            op: "press",
-            key: payload.key,
-            ...(payload.target ? { target: payload.target } : {}),
-            ...(payload.modifiers?.length ? { modifiers: payload.modifiers } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "select":
-      return payload.target && payload.values
-        ? {
-            op: "select",
-            target: payload.target,
-            values: payload.values,
-            ...(payload.labels?.length ? { labels: payload.labels } : {}),
-            ...(pageUrl ? { page_url: pageUrl } : {}),
-          }
-        : null;
-    case "navigate":
-      return null;
-  }
-}
-
-function annotateLastStepNavigation(buffer: RecordingStepBuffer, url: string): boolean {
-  for (let i = buffer.steps.length - 1; i >= 0; i -= 1) {
-    const step = buffer.steps[i];
-    if (!step) continue;
-    if (step.op === "click" || step.op === "press" || step.op === "select") {
-      buffer.steps[i] = { ...step, navigated_to: url };
-      return true;
-    }
-    break;
-  }
-  return false;
-}
-
-export function observeRecordedNavigation(
-  buffer: RecordingStepBuffer,
-  url: string,
-  causedByAction?: boolean,
-): void {
-  if (!url || url === buffer.currentUrl) return;
-  buffer.currentUrl = url;
-  const pendingIsCurrent =
-    buffer.pendingNavigation &&
-    (buffer.pendingNavigationDeadline === undefined ||
-      buffer.pendingNavigationDeadline >= Date.now());
-
-  if (causedByAction === true || (causedByAction === undefined && pendingIsCurrent)) {
-    buffer.pendingNavigation = false;
-    buffer.pendingNavigationDeadline = undefined;
-    if (!annotateLastStepNavigation(buffer, url)) {
-      buffer.steps.push({
-        op: "navigate",
-        url,
-        page_url: url,
-      });
-    }
-    return;
-  }
-
-  buffer.pendingNavigation = false;
-  buffer.pendingNavigationDeadline = undefined;
-  buffer.steps.push({
-    op: "navigate",
-    url,
-    page_url: url,
-  });
-}
-
-export function appendRecordedPayload(
-  buffer: RecordingStepBuffer,
-  payload: RecordStepPayload,
-): void {
-  if (payload.op === "navigate") {
-    if (payload.url) {
-      observeRecordedNavigation(buffer, payload.url, payload.navigation_caused_by_action);
-    }
-    return;
-  }
-  const step = toDraftStep({
-    ...payload,
-    page_url: payload.page_url ?? buffer.currentUrl,
-  });
-  if (!step) return;
-  buffer.steps.push(step);
-  if (step.op === "click" || step.op === "press" || step.op === "select" || step.op === "fill") {
-    buffer.pendingNavigation = payload.expects_navigation === true;
-    buffer.pendingNavigationDeadline = buffer.pendingNavigation
-      ? Date.now() + NAVIGATION_TRIGGER_WINDOW_MS
-      : undefined;
-  }
-}
@@ -0,0 +1,39 @@
+import {
+  RECORD_DOCUMENT_ATTRIBUTE,
+  recordingDocumentMarkerValue,
+} from "@/shared/recording-document-identity";
+
+export interface RecordingDocumentMarker {
+  restore(): void;
+  ensure(): void;
+}
+
+export function waitForDocumentElement(): Promise<HTMLElement> {
+  if (document.documentElement) return Promise.resolve(document.documentElement);
+  return new Promise((resolve) => {
+    const observer = new MutationObserver(() => {
+      if (!document.documentElement) return;
+      observer.disconnect();
+      resolve(document.documentElement);
+    });
+    observer.observe(document, { childList: true });
+  });
+}
+
+export function markRecordingDocument(
+  producerId: string,
+  root: HTMLElement = document.documentElement,
+): RecordingDocumentMarker {
+  const previous = root.getAttribute(RECORD_DOCUMENT_ATTRIBUTE);
+  const markerValue = recordingDocumentMarkerValue(producerId);
+  const ensure = () => root.setAttribute(RECORD_DOCUMENT_ATTRIBUTE, markerValue);
+  ensure();
+  return {
+    ensure,
+    restore() {
+      if (root.getAttribute(RECORD_DOCUMENT_ATTRIBUTE) !== markerValue) return;
+      if (previous === null) root.removeAttribute(RECORD_DOCUMENT_ATTRIBUTE);
+      else root.setAttribute(RECORD_DOCUMENT_ATTRIBUTE, previous);
+    },
+  };
+}
@@ -0,0 +1,134 @@
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import { type CdpRunner, sendToCdpTarget } from "@/tools/shared";
+
+const SETTLE_MIN_MS = 150;
+const SETTLE_QUIET_MS = 250;
+const SETTLE_MAX_MS = 2_000;
+const SETTLE_POLL_MS = 60;
+const SETTLE_WORLD_NAME = "__bsk_record_settle__";
+
+const QUIET_PROBE = `(() => {
+  const scope = window;
+  let probe = scope.__bskRecordQuiet;
+  if (!probe) {
+    probe = { changedAt: Date.now() };
+    const observer = new MutationObserver(() => {
+      probe.changedAt = Date.now();
+    });
+    observer.observe(document.documentElement, {
+      subtree: true,
+      childList: true,
+      attributes: true,
+      characterData: true,
+    });
+    scope.__bskRecordQuiet = probe;
+  }
+  return { idleMs: Date.now() - probe.changedAt, readyState: document.readyState };
+})()`;
+
+export interface DocumentSettleScope {
+  target: CdpTarget;
+  /** Omit only for the target's root document. */
+  frameId?: string;
+}
+
+type SettleOutcome = "quiet" | "timeout" | "cancelled";
+
+interface QuietProbe {
+  idleMs: number;
+  readyState: string;
+}
+
+interface ProbeContext {
+  executionContextId?: number;
+}
+
+function sleep(ms: number, signal?: AbortSignal): Promise<void> {
+  return new Promise((resolve) => {
+    if (signal?.aborted) return resolve();
+    const timer = setTimeout(resolve, ms);
+    signal?.addEventListener(
+      "abort",
+      () => {
+        clearTimeout(timer);
+        resolve();
+      },
+      { once: true },
+    );
+  });
+}
+
+async function executionContextForScope(
+  cdp: CdpRunner,
+  scope: DocumentSettleScope,
+): Promise<number | undefined> {
+  if (!scope.frameId) return undefined;
+  const result = await sendToCdpTarget<{ executionContextId?: number }>(
+    cdp,
+    scope.target,
+    "Page.createIsolatedWorld",
+    {
+      frameId: scope.frameId,
+      worldName: SETTLE_WORLD_NAME,
+      grantUniveralAccess: false,
+    },
+  );
+  return result.executionContextId;
+}
+
+async function readQuietProbe(
+  cdp: CdpRunner,
+  scope: DocumentSettleScope,
+  context: ProbeContext,
+): Promise<QuietProbe | null> {
+  try {
+    if (scope.frameId && context.executionContextId === undefined) {
+      context.executionContextId = await executionContextForScope(cdp, scope);
+      if (context.executionContextId === undefined) return null;
+    }
+    const reply = await sendToCdpTarget<{ result?: { value?: unknown } }>(
+      cdp,
+      scope.target,
+      "Runtime.evaluate",
+      {
+        expression: QUIET_PROBE,
+        returnByValue: true,
+        ...(context.executionContextId !== undefined
+          ? { contextId: context.executionContextId }
+          : {}),
+      },
+    );
+    const value = reply.result?.value;
+    if (!value || typeof value !== "object") return null;
+    const { idleMs, readyState } = value as { idleMs?: unknown; readyState?: unknown };
+    if (typeof idleMs !== "number" || typeof readyState !== "string") return null;
+    return { idleMs, readyState };
+  } catch {
+    context.executionContextId = undefined;
+    return null;
+  }
+}
+
+export async function waitForDocumentSettled(
+  cdp: CdpRunner,
+  scope: DocumentSettleScope,
+  options: { signal?: AbortSignal } = {},
+): Promise<SettleOutcome> {
+  const startedAt = Date.now();
+  const floor = startedAt + SETTLE_MIN_MS;
+  const deadline = startedAt + SETTLE_MAX_MS;
+  const context: ProbeContext = {};
+
+  for (;;) {
+    if (options.signal?.aborted) return "cancelled";
+    await sleep(SETTLE_POLL_MS, options.signal);
+    if (options.signal?.aborted) return "cancelled";
+
+    const probe = await readQuietProbe(cdp, scope, context);
+    const now = Date.now();
+    if (now < floor) continue;
+    if (now >= deadline) return "timeout";
+    if (!probe || probe.readyState === "loading") continue;
+    if (probe.idleMs >= SETTLE_QUIET_MS) return "quiet";
+  }
+}
@@ -0,0 +1,34 @@
+import type { RecordingDraftStep } from "./types";
+
+const CLIPBOARD_KEYS = new Set(["a", "c", "v", "x", "A", "C", "V", "X"]);
+const MODIFIER_ONLY_KEYS = new Set(["Meta", "Control", "Alt", "Shift", "OS", "Hyper", "Super"]);
+
+export function shouldRecordPress(
+  key: string,
+  modifiers?: Array<"alt" | "ctrl" | "meta" | "shift">,
+): boolean {
+  if (MODIFIER_ONLY_KEYS.has(key)) return false;
+  const mods = modifiers ?? [];
+  const hasCtrlOrMeta = mods.includes("ctrl") || mods.includes("meta");
+  if (hasCtrlOrMeta && CLIPBOARD_KEYS.has(key)) return false;
+  if (key === "Enter" || key === "Escape") return true;
+  if (key.length === 1 && !hasCtrlOrMeta && !mods.includes("alt")) return false;
+  return false;
+}
+
+export function shouldIncludeDraft(step: RecordingDraftStep): boolean {
+  return step.op !== "press" || shouldRecordPress(step.key, step.modifiers);
+}
+
+export function resolveDraftStartUrl(
+  drafts: RecordingDraftStep[],
+  explicitStartUrl?: string,
+  fallbackUrl?: string,
+): string {
+  if (explicitStartUrl) return explicitStartUrl;
+  const navigation = drafts.find(
+    (step): step is Extract<RecordingDraftStep, { op: "navigate" }> => step.op === "navigate",
+  );
+  if (navigation) return navigation.url;
+  return drafts.find((step) => step.pageUrl)?.pageUrl ?? fallbackUrl ?? "about:blank";
+}
@@ -0,0 +1,65 @@
+export const RECORD_FRAME_PORT = "bsk-record-frame";
+export const RECORD_FRAME_QUERY = "bsk-record-frame-query";
+export const RECORD_FRAME_START = "bsk-record-frame-start";
+
+export interface RecordFrameQueryMessage {
+  type: typeof RECORD_FRAME_QUERY;
+}
+
+export interface RecordFrameQueryResponse {
+  active: boolean;
+  requestId?: string;
+  startedAtMs?: number;
+}
+
+export interface RecordFrameStartMessage {
+  type: typeof RECORD_FRAME_START;
+  requestId: string;
+  startedAtMs: number;
+}
+
+export type RecordFramePortMessage =
+  | {
+      type: "ready";
+      requestId: string;
+      producerId: string;
+    }
+  | {
+      type: "ready_ack";
+      requestId: string;
+      producerId: string;
+    }
+  | {
+      type: "stop";
+      requestId: string;
+      commandId: string;
+    }
+  | {
+      type: "cancel";
+      requestId: string;
+    }
+  | {
+      type: "stopped";
+      requestId: string;
+      commandId: string;
+      ok: boolean;
+      error?: string;
+    };
+
+export function isRecordFrameQueryMessage(value: unknown): value is RecordFrameQueryMessage {
+  return (
+    typeof value === "object" &&
+    value !== null &&
+    (value as { type?: unknown }).type === RECORD_FRAME_QUERY
+  );
+}
+
+export function isRecordFrameStartMessage(value: unknown): value is RecordFrameStartMessage {
+  if (typeof value !== "object" || value === null) return false;
+  const message = value as Partial<RecordFrameStartMessage>;
+  return (
+    message.type === RECORD_FRAME_START &&
+    typeof message.requestId === "string" &&
+    typeof message.startedAtMs === "number"
+  );
+}
@@ -0,0 +1,399 @@
+import {
+  isRecordFrameQueryMessage,
+  RECORD_FRAME_PORT,
+  RECORD_FRAME_START,
+  type RecordFramePortMessage,
+  type RecordFrameQueryResponse,
+  type RecordFrameStartMessage,
+} from "./frame-bridge";
+
+export interface RecordingCaptureScope {
+  tabId: number;
+  documentId: string;
+  browserFrameId: number;
+  producerId: string;
+}
+
+interface ArmedRecording {
+  requestId: string;
+  startedAtMs: number;
+  tabIds: Set<number>;
+  agents: Map<string, FrameAgent>;
+  onDocumentReady?: (scope: RecordingCaptureScope) => void | Promise<void>;
+  finishing: boolean;
+}
+
+interface FrameAgent extends RecordingCaptureScope {
+  requestId: string;
+  port: chrome.runtime.Port;
+  stopWaiters: Map<string, (ok: boolean) => void>;
+}
+
+interface BrowserFrame {
+  frameId: number;
+  documentId?: string;
+}
+
+interface BrowserFrameNavigation extends BrowserFrame {
+  tabId: number;
+  lifecycle: "committed" | "completed";
+}
+
+const RECORD_FRAME_STOP_TIMEOUT_MS = 5_000;
+
+export interface RecordFrameCoordinatorDeps {
+  getAllFrames(tabId: number): Promise<BrowserFrame[]>;
+  sendToDocument(
+    tabId: number,
+    message: RecordFrameStartMessage,
+    target: { documentId?: string; frameId?: number },
+  ): Promise<unknown>;
+  subscribeFrameNavigation?(listener: (frame: BrowserFrameNavigation) => void): () => void;
+}
+
+function documentKey(tabId: number, documentId: string): string {
+  return `${tabId}:${documentId}`;
+}
+
+function senderAddress(
+  sender: chrome.runtime.MessageSender,
+): { tabId: number; documentId: string; browserFrameId: number } | null {
+  const tabId = sender.tab?.id;
+  const documentId = sender.documentId;
+  const browserFrameId = sender.frameId;
+  if (
+    typeof tabId !== "number" ||
+    typeof documentId !== "string" ||
+    typeof browserFrameId !== "number"
+  ) {
+    return null;
+  }
+  return { tabId, documentId, browserFrameId };
+}
+
+function defaultDeps(): RecordFrameCoordinatorDeps {
+  return {
+    async getAllFrames(tabId) {
+      return (await chrome.webNavigation.getAllFrames({ tabId })) ?? [];
+    },
+    sendToDocument(tabId, message, target) {
+      return chrome.tabs.sendMessage(tabId, message, target);
+    },
+    subscribeFrameNavigation(listener) {
+      const onCommitted = (details: chrome.webNavigation.WebNavigationTransitionCallbackDetails) =>
+        listener({ ...details, lifecycle: "committed" });
+      const onCompleted = (details: chrome.webNavigation.WebNavigationFramedCallbackDetails) =>
+        listener({ ...details, lifecycle: "completed" });
+      chrome.webNavigation.onCommitted.addListener(onCommitted);
+      chrome.webNavigation.onCompleted.addListener(onCompleted);
+      return () => {
+        chrome.webNavigation.onCommitted.removeListener(onCommitted);
+        chrome.webNavigation.onCompleted.removeListener(onCompleted);
+      };
+    },
+  };
+}
+
+export class RecordFrameCoordinator {
+  readonly #deps: RecordFrameCoordinatorDeps;
+  readonly #recordings = new Map<string, ArmedRecording>();
+  #attached = false;
+  #detachFrameNavigation: (() => void) | null = null;
+
+  constructor(deps: RecordFrameCoordinatorDeps = defaultDeps()) {
+    this.#deps = deps;
+  }
+
+  attach(): () => void {
+    if (this.#attached) return () => {};
+    this.#attached = true;
+    chrome.runtime.onConnect.addListener(this.#onConnect);
+    chrome.runtime.onMessage.addListener(this.#onMessage);
+    this.#detachFrameNavigation =
+      this.#deps.subscribeFrameNavigation?.(this.#onFrameNavigation) ?? null;
+    return () => {
+      if (!this.#attached) return;
+      this.#attached = false;
+      chrome.runtime.onConnect.removeListener(this.#onConnect);
+      chrome.runtime.onMessage.removeListener(this.#onMessage);
+      this.#detachFrameNavigation?.();
+      this.#detachFrameNavigation = null;
+      for (const recording of this.#recordings.values()) this.#cancelAgents(recording);
+      this.#recordings.clear();
+    };
+  }
+
+  begin(
+    requestId: string,
+    startedAtMs: number,
+    initialTabId: number,
+    onDocumentReady?: (scope: RecordingCaptureScope) => void | Promise<void>,
+  ): void {
+    const previous = this.#recordings.get(requestId);
+    if (previous) this.#cancelAgents(previous);
+    this.#recordings.set(requestId, {
+      requestId,
+      startedAtMs,
+      // Register the initial tab before navigation begins. A newly-created
+      // child document can query at document_start before armTab's frame
+      // snapshot sees it, especially when Chromium promotes it to an OOPIF.
+      tabIds: new Set([initialTabId]),
+      agents: new Map(),
+      ...(onDocumentReady ? { onDocumentReady } : {}),
+      finishing: false,
+    });
+  }
+
+  async armTab(requestId: string, tabId: number): Promise<boolean> {
+    const recording = this.#recordings.get(requestId);
+    if (!recording || recording.finishing) return false;
+    recording.tabIds.add(tabId);
+
+    let frames: BrowserFrame[];
+    try {
+      frames = await this.#deps.getAllFrames(tabId);
+    } catch {
+      frames = [{ frameId: 0 }];
+    }
+    if (!frames.some((frame) => frame.frameId === 0)) frames.unshift({ frameId: 0 });
+
+    const results = await Promise.all(
+      frames.map(async (frame) => {
+        const started = await this.#startFrame(recording, tabId, frame);
+        return { frameId: frame.frameId, started };
+      }),
+    );
+    return results.some((result) => result.frameId === 0 && result.started);
+  }
+
+  sourceFor(
+    requestId: string,
+    producerId: string,
+    sender: chrome.runtime.MessageSender,
+  ): RecordingCaptureScope | null {
+    const address = senderAddress(sender);
+    const recording = this.#recordings.get(requestId);
+    if (!address || !recording) return null;
+    const agent = recording.agents.get(documentKey(address.tabId, address.documentId));
+    if (!agent || agent.producerId !== producerId) return null;
+    return {
+      tabId: agent.tabId,
+      documentId: agent.documentId,
+      browserFrameId: agent.browserFrameId,
+      producerId: agent.producerId,
+    };
+  }
+
+  async stop(requestId: string): Promise<boolean> {
+    const recording = this.#recordings.get(requestId);
+    if (!recording) return true;
+    recording.finishing = true;
+    const commandId = crypto.randomUUID();
+    const results = await Promise.all(
+      [...recording.agents.values()].map((agent) => this.#stopAgent(agent, requestId, commandId)),
+    );
+    const succeeded = results.every(Boolean);
+    if (succeeded) this.#recordings.delete(requestId);
+    else recording.finishing = false;
+    return succeeded;
+  }
+
+  cancel(requestId: string): void {
+    const recording = this.#recordings.get(requestId);
+    if (!recording) return;
+    this.#cancelAgents(recording);
+    this.#recordings.delete(requestId);
+  }
+
+  readonly #onMessage = (
+    message: unknown,
+    sender: chrome.runtime.MessageSender,
+    sendResponse: (response: RecordFrameQueryResponse) => void,
+  ): boolean => {
+    if (!isRecordFrameQueryMessage(message)) return false;
+    const tabId = sender.tab?.id;
+    const recording =
+      typeof tabId === "number"
+        ? [...this.#recordings.values()].find(
+            (candidate) => !candidate.finishing && candidate.tabIds.has(tabId),
+          )
+        : undefined;
+    sendResponse(
+      recording
+        ? {
+            active: true,
+            requestId: recording.requestId,
+            startedAtMs: recording.startedAtMs,
+          }
+        : { active: false },
+    );
+    return false;
+  };
+
+  readonly #onFrameNavigation = (frame: BrowserFrameNavigation): void => {
+    if (frame.frameId === 0) return;
+    for (const recording of this.#recordings.values()) {
+      if (recording.finishing || !recording.tabIds.has(frame.tabId)) continue;
+      // onCommitted can race document_start, while onCompleted runs after the
+      // content script is available. Starting twice is safe and closes both
+      // the early-query and late-SPA-frame gaps.
+      void (async () => {
+        const started = await this.#startFrame(recording, frame.tabId, frame);
+        if (!started || frame.lifecycle !== "completed" || recording.finishing) return;
+        const agent = frame.documentId
+          ? recording.agents.get(documentKey(frame.tabId, frame.documentId))
+          : [...recording.agents.values()].find(
+              (candidate) =>
+                candidate.tabId === frame.tabId && candidate.browserFrameId === frame.frameId,
+            );
+        if (!agent) return;
+        await recording.onDocumentReady?.({
+          tabId: agent.tabId,
+          documentId: agent.documentId,
+          browserFrameId: agent.browserFrameId,
+          producerId: agent.producerId,
+        });
+      })();
+    }
+  };
+
+  readonly #onConnect = (port: chrome.runtime.Port): void => {
+    if (port.name !== RECORD_FRAME_PORT) return;
+    const address = senderAddress(port.sender ?? {});
+    if (!address) {
+      port.disconnect();
+      return;
+    }
+    let registered: FrameAgent | null = null;
+    port.onMessage.addListener((raw: unknown) => {
+      const message = raw as Partial<RecordFramePortMessage>;
+      if (message.type === "ready") {
+        if (typeof message.requestId !== "string" || typeof message.producerId !== "string") {
+          port.disconnect();
+          return;
+        }
+        const requestId = message.requestId;
+        const producerId = message.producerId;
+        if (registered) {
+          if (registered.requestId === requestId && registered.producerId === producerId) {
+            port.postMessage({
+              type: "ready_ack",
+              requestId,
+              producerId,
+            } satisfies RecordFramePortMessage);
+          } else {
+            port.disconnect();
+          }
+          return;
+        }
+        const recording = this.#recordings.get(requestId);
+        if (
+          !recording ||
+          recording.finishing ||
+          !recording.tabIds.has(address.tabId) ||
+          producerId.length === 0
+        ) {
+          port.disconnect();
+          return;
+        }
+        const agent: FrameAgent = {
+          ...address,
+          requestId,
+          producerId,
+          port,
+          stopWaiters: new Map(),
+        };
+        registered = agent;
+        const key = documentKey(address.tabId, address.documentId);
+        const previous = recording.agents.get(key);
+        if (previous && previous !== agent) previous.port.disconnect();
+        recording.agents.set(key, agent);
+        port.postMessage({
+          type: "ready_ack",
+          requestId,
+          producerId,
+        } satisfies RecordFramePortMessage);
+        return;
+      }
+      if (
+        message.type === "stopped" &&
+        registered &&
+        message.requestId === registered.requestId &&
+        typeof message.commandId === "string"
+      ) {
+        registered.stopWaiters.get(message.commandId)?.(message.ok === true);
+        registered.stopWaiters.delete(message.commandId);
+      }
+    });
+    port.onDisconnect.addListener(() => {
+      if (!registered) return;
+      for (const resolve of registered.stopWaiters.values()) resolve(true);
+      const recording = this.#recordings.get(registered.requestId);
+      const key = documentKey(registered.tabId, registered.documentId);
+      if (recording?.agents.get(key) === registered) recording.agents.delete(key);
+    });
+  };
+
+  #stopAgent(agent: FrameAgent, requestId: string, commandId: string): Promise<boolean> {
+    return new Promise((resolve) => {
+      const timer = setTimeout(() => {
+        agent.stopWaiters.delete(commandId);
+        resolve(false);
+      }, RECORD_FRAME_STOP_TIMEOUT_MS);
+      agent.stopWaiters.set(commandId, (ok) => {
+        clearTimeout(timer);
+        resolve(ok);
+      });
+      try {
+        agent.port.postMessage({
+          type: "stop",
+          requestId,
+          commandId,
+        } satisfies RecordFramePortMessage);
+      } catch {
+        clearTimeout(timer);
+        agent.stopWaiters.delete(commandId);
+        resolve(true);
+      }
+    });
+  }
+
+  async #startFrame(
+    recording: ArmedRecording,
+    tabId: number,
+    frame: BrowserFrame,
+  ): Promise<boolean> {
+    const message: RecordFrameStartMessage = {
+      type: RECORD_FRAME_START,
+      requestId: recording.requestId,
+      startedAtMs: recording.startedAtMs,
+    };
+    try {
+      const response = await this.#deps.sendToDocument(tabId, message, {
+        ...(frame.documentId ? { documentId: frame.documentId } : { frameId: frame.frameId }),
+      });
+      return isStarted(response);
+    } catch {
+      return false;
+    }
+  }
+
+  #cancelAgents(recording: ArmedRecording): void {
+    for (const agent of recording.agents.values()) {
+      try {
+        agent.port.postMessage({
+          type: "cancel",
+          requestId: recording.requestId,
+        } satisfies RecordFramePortMessage);
+      } catch {
+        // A destroyed Document has no remaining capture state to cancel.
+      }
+    }
+  }
+}
+
+function isStarted(value: unknown): boolean {
+  return typeof value === "object" && value !== null && (value as { ok?: unknown }).ok === true;
+}
+
+export const recordFrameCoordinator = new RecordFrameCoordinator();
@@ -0,0 +1,5 @@
+const REDIRECT_QUALIFIERS = new Set(["client_redirect", "server_redirect"]);
+
+export function hasRedirectQualifier(qualifiers?: readonly string[]): boolean {
+  return (qualifiers ?? []).some((qualifier) => REDIRECT_QUALIFIERS.has(qualifier));
+}
@@ -0,0 +1,140 @@
+import type { RenderedRef } from "@browser-skill/vom";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import {
+  type CaptureVomMatchNode,
+  type CaptureVomObservationResult,
+  captureVomObservation,
+} from "@/tools/capture-vom-observation";
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+
+export interface IndexedObservationNode {
+  frameId: string;
+  geometry: CaptureVomMatchNode;
+  ref?: RenderedRef;
+}
+
+export interface CapturedRecordingObservation {
+  rootFrameId: string;
+  index: ObservationNodeIndex;
+  url: string;
+  title?: string;
+  vomText: string;
+  truncated: boolean;
+}
+
+export interface RegisteredObservation {
+  stateId: string;
+  rootFrameId: string;
+  index: ObservationNodeIndex;
+  url: string;
+}
+
+export interface RecordingDocumentScope {
+  frameId: string;
+  target: CdpTarget;
+}
+
+function nodeKey(frameId: string, backendNodeId: number): string {
+  return `${frameId}:${backendNodeId}`;
+}
+
+function frameTagKey(frameId: string, tag: string): string {
+  return `${frameId}:${tag.toLowerCase()}`;
+}
+
+export class ObservationNodeIndex {
+  readonly #nodesByFrameTag = new Map<string, IndexedObservationNode[]>();
+  readonly #refById = new Map<string, RenderedRef>();
+  readonly #refsByFrame = new Map<string, RenderedRef[]>();
+  readonly #scopeByProducer = new Map<string, RecordingDocumentScope | null>();
+
+  constructor(
+    input: Pick<CaptureVomObservationResult, "rootFrameId" | "matchNodes" | "refs"> &
+      Partial<Pick<CaptureVomObservationResult, "frames">>,
+  ) {
+    const refByNode = new Map<string, RenderedRef>();
+    for (const ref of input.refs) {
+      const frameId = ref.frameId ?? input.rootFrameId;
+      refByNode.set(nodeKey(frameId, ref.backendNodeId), ref);
+      this.#refById.set(ref.ref, ref);
+      const frameRefs = this.#refsByFrame.get(frameId) ?? [];
+      frameRefs.push(ref);
+      this.#refsByFrame.set(frameId, frameRefs);
+    }
+    for (const frame of input.frames ?? []) {
+      const documentId = frame.recordingDocumentId;
+      if (!documentId) continue;
+      this.#scopeByProducer.set(
+        documentId,
+        this.#scopeByProducer.has(documentId)
+          ? null
+          : { frameId: frame.frameId, target: frame.target },
+      );
+    }
+    for (const geometry of input.matchNodes) {
+      const { frameId } = geometry;
+      const entry = {
+        frameId,
+        geometry,
+        ref: refByNode.get(nodeKey(frameId, geometry.backendNodeId)),
+      };
+      const key = frameTagKey(frameId, geometry.tag);
+      const bucket = this.#nodesByFrameTag.get(key) ?? [];
+      bucket.push(entry);
+      this.#nodesByFrameTag.set(key, bucket);
+    }
+  }
+
+  candidates(frameId: string, tag: string): readonly IndexedObservationNode[] {
+    return this.#nodesByFrameTag.get(frameTagKey(frameId, tag)) ?? [];
+  }
+
+  ref(refId: string): RenderedRef | undefined {
+    return this.#refById.get(refId);
+  }
+
+  refs(frameId: string): readonly RenderedRef[] {
+    return this.#refsByFrame.get(frameId) ?? [];
+  }
+
+  documentScope(producerId: string): RecordingDocumentScope | undefined {
+    return this.#scopeByProducer.get(producerId) ?? undefined;
+  }
+}
+
+async function readTabMeta(
+  tabsApi: ChromeTabsApi,
+  tabId: number,
+): Promise<{ url: string; title?: string }> {
+  try {
+    const tab = await tabsApi.get(tabId);
+    return { url: tab.url ?? "about:blank", title: tab.title };
+  } catch {
+    return { url: "about:blank" };
+  }
+}
+
+export async function captureRecordingObservation(input: {
+  cdp: CdpRunner;
+  tabsApi: ChromeTabsApi;
+  tabId: number;
+  maxTokens: number;
+  redactValues: boolean;
+  signal?: AbortSignal;
+}): Promise<CapturedRecordingObservation> {
+  const { url, title } = await readTabMeta(input.tabsApi, input.tabId);
+  const captured = await captureVomObservation(input.cdp, input.tabId, url, {
+    maxTokens: input.maxTokens,
+    redactValues: input.redactValues,
+    conditionalSurfaceProbe: false,
+    signal: input.signal,
+  });
+  return {
+    rootFrameId: captured.rootFrameId,
+    index: new ObservationNodeIndex(captured),
+    url,
+    title,
+    vomText: captured.text,
+    truncated: captured.truncated,
+  };
+}
@@ -0,0 +1,128 @@
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import { captureRecordingObservation, type RegisteredObservation } from "./observation-capture";
+import { RecordingStateRegistry } from "./state-registry";
+import { matchObservationTarget, unmatchedTarget } from "./target-matcher";
+import type { RecordingDraftStep, StepAnnotation, TargetedRecordingDraft } from "./types";
+
+const DEFAULT_MAX_PAGE_TOKENS = 3_000;
+const MIN_CAPTURE_INTERVAL_MS = 200;
+
+export interface TabObservationCursor {
+  lastSettled: RegisteredObservation | null;
+  lastCaptureAt: number;
+}
+
+function abortableDelay(ms: number, signal?: AbortSignal): Promise<void> {
+  return new Promise((resolve) => {
+    if (signal?.aborted) return resolve();
+    const timer = setTimeout(resolve, ms);
+    signal?.addEventListener(
+      "abort",
+      () => {
+        clearTimeout(timer);
+        resolve();
+      },
+      { once: true },
+    );
+  });
+}
+
+function isTargeted(draft: RecordingDraftStep): draft is TargetedRecordingDraft {
+  return (
+    draft.op === "click" ||
+    draft.op === "hover" ||
+    draft.op === "fill" ||
+    draft.op === "press" ||
+    draft.op === "select"
+  );
+}
+
+export class RecordingObservationSession {
+  readonly registry: RecordingStateRegistry;
+  readonly cursor: TabObservationCursor;
+  readonly annotations: StepAnnotation[];
+  readonly #maxTokens: number;
+  readonly #redactValues: boolean;
+
+  constructor(
+    options: {
+      registry?: RecordingStateRegistry;
+      cursor?: TabObservationCursor;
+      annotations?: StepAnnotation[];
+      maxTokens?: number;
+      redactValues?: boolean;
+    } = {},
+  ) {
+    this.registry = options.registry ?? new RecordingStateRegistry();
+    this.cursor = options.cursor ?? { lastSettled: null, lastCaptureAt: 0 };
+    this.annotations = options.annotations ?? [];
+    this.#maxTokens = options.maxTokens ?? DEFAULT_MAX_PAGE_TOKENS;
+    this.#redactValues = options.redactValues ?? false;
+  }
+
+  async capture(
+    cdp: CdpRunner,
+    tabsApi: ChromeTabsApi,
+    tabId: number,
+    signal?: AbortSignal,
+  ): Promise<RegisteredObservation> {
+    const waitMs = Math.max(0, MIN_CAPTURE_INTERVAL_MS - (Date.now() - this.cursor.lastCaptureAt));
+    if (waitMs > 0) await abortableDelay(waitMs, signal);
+    if (signal?.aborted) throw new DOMException("observation aborted", "AbortError");
+    const captured = await captureRecordingObservation({
+      cdp,
+      tabsApi,
+      tabId,
+      maxTokens: this.#maxTokens,
+      redactValues: this.#redactValues,
+      signal,
+    });
+    const state = this.registry.register({
+      url: captured.url,
+      title: captured.title,
+      vomText: captured.vomText,
+      truncated: captured.truncated,
+    });
+    const observation: RegisteredObservation = {
+      stateId: state.id,
+      rootFrameId: captured.rootFrameId,
+      index: captured.index,
+      url: captured.url,
+    };
+    this.cursor.lastSettled = observation;
+    this.cursor.lastCaptureAt = Date.now();
+    return observation;
+  }
+
+  bindDraft(draft: RecordingDraftStep, draftId: number, previousActionPending = false): void {
+    const observation = this.cursor.lastSettled;
+    if (isTargeted(draft)) {
+      draft.matchedTarget = observation
+        ? matchObservationTarget({
+            observation,
+            hint: draft.targetHint,
+            fallback: draft.captureTarget,
+          })
+        : unmatchedTarget(draft.captureTarget);
+    }
+    if (!observation) return;
+
+    const unmatched = isTargeted(draft) && draft.matchedTarget?.unmatched === true;
+    if (previousActionPending && unmatched) return;
+    draft.preStateId = observation.stateId;
+    this.registry.markStep(observation.stateId, draftId);
+
+    if (!isTargeted(draft) || !draft.matchedTarget?.ref) return;
+    const ref = observation.index.ref(draft.matchedTarget.ref);
+    if (!ref) return;
+    this.annotations.push({
+      draftId,
+      op: draft.op,
+      line: ref.line,
+      stateId: observation.stateId,
+      ...(draft.op === "fill" && !this.#redactValues
+        ? { detail: JSON.stringify(draft.value) }
+        : {}),
+    });
+  }
+}
@@ -0,0 +1,277 @@
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import type { StopReason, TraceV3 } from "@/transport/types";
+import { type DocumentSettleScope, waitForDocumentSettled } from "./document-settle";
+import type { RegisteredObservation } from "./observation-capture";
+import { RecordingObservationSession } from "./observation-session";
+import { inferMissingPostStates, SettleController } from "./settle-controller";
+import { RecordingStateRegistry } from "./state-registry";
+import { buildTraceV3 } from "./trace-builder-v3";
+import type { RecordingDraftStep, StepAnnotation } from "./types";
+
+interface TabRecordingContext {
+  session: RecordingObservationSession;
+  settle: SettleController;
+  pendingCapture: PendingCapture | null;
+  frameRefresh: Promise<void>;
+  frameRefreshAbort: AbortController | null;
+}
+
+interface PendingCapture {
+  promise: Promise<RegisteredObservation>;
+  abort: AbortController;
+}
+
+export class RecordingObservationRuntime {
+  readonly #cdp: CdpRunner;
+  readonly #tabsApi: ChromeTabsApi;
+  readonly #registry = new RecordingStateRegistry();
+  readonly #annotations: StepAnnotation[] = [];
+  readonly #contexts = new Map<number, TabRecordingContext>();
+  readonly #maxTokens?: number;
+  readonly #redactValues: boolean;
+
+  constructor(input: {
+    cdp: CdpRunner;
+    tabsApi: ChromeTabsApi;
+    maxTokens?: number;
+    redactValues?: boolean;
+  }) {
+    this.#cdp = input.cdp;
+    this.#tabsApi = input.tabsApi;
+    this.#maxTokens = input.maxTokens;
+    this.#redactValues = input.redactValues ?? false;
+  }
+
+  #context(tabId: number): TabRecordingContext {
+    const existing = this.#contexts.get(tabId);
+    if (existing) return existing;
+    const session = new RecordingObservationSession({
+      registry: this.#registry,
+      annotations: this.#annotations,
+      maxTokens: this.#maxTokens,
+      redactValues: this.#redactValues,
+    });
+    const context: TabRecordingContext = {
+      session,
+      settle: new SettleController({
+        session,
+        cdp: this.#cdp,
+        tabsApi: this.#tabsApi,
+        tabId,
+      }),
+      pendingCapture: null,
+      frameRefresh: Promise.resolve(),
+      frameRefreshAbort: null,
+    };
+    this.#contexts.set(tabId, context);
+    return context;
+  }
+
+  async #capture(tabId: number): Promise<RegisteredObservation> {
+    const context = this.#context(tabId);
+    if (context.pendingCapture) return context.pendingCapture.promise;
+
+    const abort = new AbortController();
+    let pending!: PendingCapture;
+    const promise = context.session.capture(this.#cdp, this.#tabsApi, tabId, abort.signal);
+    pending = {
+      abort,
+      promise: promise.finally(() => {
+        if (context.pendingCapture === pending) context.pendingCapture = null;
+      }),
+    };
+    context.pendingCapture = pending;
+    return pending.promise;
+  }
+
+  async captureInitial(tabId: number): Promise<void> {
+    const context = this.#context(tabId);
+    if (context.session.cursor.lastSettled) return;
+    await this.#capture(tabId);
+  }
+
+  /** Refresh the safe observation after a late child Document becomes usable. */
+  async refreshDocument(tabId: number, producerId: string): Promise<void> {
+    const context = this.#context(tabId);
+    context.frameRefreshAbort?.abort();
+    const abort = new AbortController();
+    context.frameRefreshAbort = abort;
+    const previous = context.frameRefresh;
+    const refresh = (async () => {
+      await previous;
+      if (abort.signal.aborted) return;
+      if (context.pendingCapture) await Promise.allSettled([context.pendingCapture.promise]);
+      if (abort.signal.aborted) return;
+
+      // The first capture discovers the safe producer -> CDP Document scope.
+      await this.#capture(tabId);
+      if (abort.signal.aborted) return;
+      const scope = context.session.cursor.lastSettled?.index.documentScope(producerId);
+      if (scope) {
+        await waitForDocumentSettled(this.#cdp, scope, { signal: abort.signal });
+      }
+      if (abort.signal.aborted) return;
+
+      // Capture again after the child SPA is quiet so the next action can be
+      // matched against refs that actually exist in its pre-action state.
+      await this.#capture(tabId);
+    })();
+    const tracked = refresh.catch(() => {});
+    context.frameRefresh = tracked;
+    try {
+      await refresh;
+    } finally {
+      if (context.frameRefresh === tracked) context.frameRefreshAbort = null;
+    }
+  }
+
+  async captureTabTransition(
+    fromTabId: number,
+    toTabId: number,
+  ): Promise<{ preStateId?: string; postStateId?: string; targetUrl?: string }> {
+    const from = this.#context(fromTabId);
+    await this.#flushContext(from);
+    if (!from.session.cursor.lastSettled) {
+      try {
+        await this.captureInitial(fromTabId);
+      } catch {
+        // A target-tab observation can still preserve the forward transition.
+      }
+    }
+
+    const to = this.#context(toTabId);
+    let target = to.session.cursor.lastSettled;
+    try {
+      target = await this.#capture(toTabId);
+    } catch {
+      // Reuse the last settled target state when a refresh races navigation.
+    }
+
+    const source = from.session.cursor.lastSettled;
+    return {
+      ...(source ? { preStateId: source.stateId } : {}),
+      ...(target ? { postStateId: target.stateId, targetUrl: target.url } : {}),
+    };
+  }
+
+  bindTabTransition(
+    draft: Extract<RecordingDraftStep, { op: "switch_tab" }>,
+    draftId: number,
+  ): void {
+    if (draft.preStateId) this.#registry.markStep(draft.preStateId, draftId);
+  }
+
+  async processDraft(
+    tabId: number,
+    drafts: RecordingDraftStep[],
+    draftIndex: number,
+    producerId?: string,
+  ): Promise<void> {
+    const draft = drafts[draftIndex];
+    if (!draft) return;
+    const context = this.#context(tabId);
+    if (!context.session.cursor.lastSettled) {
+      try {
+        await this.captureInitial(tabId);
+      } catch {
+        // Post-action settle can still provide a usable state.
+      }
+    }
+    const scope = producerId
+      ? context.session.cursor.lastSettled?.index.documentScope(producerId)
+      : undefined;
+    if (
+      producerId &&
+      (draft.op === "click" ||
+        draft.op === "hover" ||
+        draft.op === "fill" ||
+        draft.op === "press" ||
+        draft.op === "select")
+    ) {
+      draft.targetHint = {
+        ...(draft.targetHint ?? {}),
+        frameId: scope?.frameId ?? null,
+        geometrySpace: "local",
+      };
+    }
+    context.session.bindDraft(draft, draftIndex + 1, context.settle.hasPending);
+    context.settle.schedule(drafts, draftIndex, scope);
+  }
+
+  scheduleSettle(
+    tabId: number,
+    drafts: RecordingDraftStep[],
+    draftIndex: number,
+    scope?: DocumentSettleScope,
+  ): void {
+    this.#context(tabId).settle.schedule(drafts, draftIndex, scope);
+  }
+
+  clearRedirect(tabId: number): void {
+    this.#contexts.get(tabId)?.settle.clearRedirect();
+  }
+
+  scheduleRedirect(tabId: number, drafts: RecordingDraftStep[], url: string): void {
+    this.#context(tabId).settle.scheduleRedirect(drafts, url);
+  }
+
+  async #flushContext(context: TabRecordingContext): Promise<void> {
+    await context.frameRefresh;
+    if (context.pendingCapture) await Promise.allSettled([context.pendingCapture.promise]);
+    await context.settle.flushRedirects();
+    await context.settle.flush();
+  }
+
+  async flushRedirects(tabId: number): Promise<void> {
+    await this.#contexts.get(tabId)?.settle.flushRedirects();
+  }
+
+  async flush(): Promise<void> {
+    for (const context of this.#contexts.values()) await this.#flushContext(context);
+  }
+
+  async settleTrailing(tabId: number, drafts: RecordingDraftStep[]): Promise<void> {
+    const context = this.#context(tabId);
+    if (context.pendingCapture) await Promise.allSettled([context.pendingCapture.promise]);
+    if (!context.session.cursor.lastSettled) {
+      try {
+        await this.captureInitial(tabId);
+      } catch {
+        // The trace may remain observation-free when CDP is unavailable.
+      }
+    }
+    await context.settle.settleTrailing(drafts);
+    inferMissingPostStates(drafts);
+  }
+
+  cancel(): void {
+    for (const context of this.#contexts.values()) {
+      context.frameRefreshAbort?.abort();
+      context.pendingCapture?.abort.abort();
+      context.settle.cancel();
+    }
+  }
+
+  buildTrace(input: {
+    drafts: RecordingDraftStep[];
+    startedAt: string;
+    purpose?: string;
+    startUrl?: string;
+    stoppedBy: StopReason;
+    bskVersion: string;
+    includeTabSwitches?: boolean;
+  }): TraceV3 {
+    return buildTraceV3({
+      registry: this.#registry,
+      drafts: input.drafts,
+      annotations: this.#annotations,
+      startedAt: input.startedAt,
+      purpose: input.purpose,
+      startUrl: input.startUrl,
+      stoppedBy: input.stoppedBy,
+      bskVersion: input.bskVersion,
+      redactValues: this.#redactValues,
+      includeTabSwitches: input.includeTabSwitches,
+    });
+  }
+}
@@ -0,0 +1,233 @@
+import type { CdpRunner, ChromeTabsApi } from "@/tools/shared";
+import { type DocumentSettleScope, waitForDocumentSettled } from "./document-settle";
+import { RecordingObservationSession } from "./observation-session";
+import type { RecordingDraftStep } from "./types";
+
+interface PendingSettle {
+  abort: AbortController;
+  scope: DocumentSettleScope;
+}
+
+interface PendingRedirect {
+  url: string;
+  abort: AbortController;
+}
+
+const CAPTURE_RETRY_DELAY_MS = 250;
+
+function delay(ms: number, signal?: AbortSignal): Promise<void> {
+  return new Promise((resolve) => {
+    if (signal?.aborted) return resolve();
+    const timer = setTimeout(resolve, ms);
+    signal?.addEventListener(
+      "abort",
+      () => {
+        clearTimeout(timer);
+        resolve();
+      },
+      { once: true },
+    );
+  });
+}
+
+function isAbortError(error: unknown): boolean {
+  return (
+    typeof error === "object" &&
+    error !== null &&
+    (error as { name?: string }).name === "AbortError"
+  );
+}
+
+export function inferMissingPostStates(drafts: RecordingDraftStep[]): void {
+  for (let index = 0; index < drafts.length - 1; index += 1) {
+    const draft = drafts[index];
+    const next = drafts[index + 1];
+    if (draft && next && !draft.postStateId && next.preStateId) {
+      draft.postStateId = next.preStateId;
+    }
+  }
+}
+
+export class SettleController {
+  readonly #session: RecordingObservationSession;
+  readonly #cdp: CdpRunner;
+  readonly #tabsApi: ChromeTabsApi;
+  readonly #tabId: number;
+  readonly #rootScope: DocumentSettleScope;
+  readonly #pending = new Map<number, PendingSettle>();
+  #queue = Promise.resolve();
+  #pendingRedirect: PendingRedirect | null = null;
+  #redirectQueue = Promise.resolve();
+
+  constructor(input: {
+    session: RecordingObservationSession;
+    cdp: CdpRunner;
+    tabsApi: ChromeTabsApi;
+    tabId: number;
+  }) {
+    this.#session = input.session;
+    this.#cdp = input.cdp;
+    this.#tabsApi = input.tabsApi;
+    this.#tabId = input.tabId;
+    this.#rootScope = { target: { tabId: input.tabId } };
+  }
+
+  get hasPending(): boolean {
+    return this.#pending.size > 0 || this.#pendingRedirect !== null;
+  }
+
+  async #captureWithRetry(signal?: AbortSignal) {
+    try {
+      return await this.#session.capture(this.#cdp, this.#tabsApi, this.#tabId, signal);
+    } catch (error) {
+      if (signal?.aborted) throw error;
+      await delay(CAPTURE_RETRY_DELAY_MS, signal);
+      return this.#session.capture(this.#cdp, this.#tabsApi, this.#tabId, signal);
+    }
+  }
+
+  schedule(
+    drafts: RecordingDraftStep[],
+    draftIndex: number,
+    scope: DocumentSettleScope = this.#rootScope,
+  ): void {
+    if (scope.target.tabId !== this.#tabId) {
+      throw new Error(
+        `settle scope tab ${scope.target.tabId} does not belong to tab ${this.#tabId}`,
+      );
+    }
+    const landing = drafts[draftIndex]?.preStateId;
+    for (const [index, pending] of this.#pending) {
+      if (index >= draftIndex) continue;
+      pending.abort.abort();
+      this.#pending.delete(index);
+      if (landing && drafts[index] && !drafts[index].postStateId) {
+        drafts[index].postStateId = landing;
+      }
+    }
+
+    this.#pending.get(draftIndex)?.abort.abort();
+    const pending = { abort: new AbortController(), scope };
+    this.#pending.set(draftIndex, pending);
+    const task = async () => {
+      if (pending.abort.signal.aborted) return;
+      try {
+        const outcome = await waitForDocumentSettled(this.#cdp, pending.scope, {
+          signal: pending.abort.signal,
+        });
+        if (outcome === "cancelled") return;
+        const observation = await this.#captureWithRetry(pending.abort.signal);
+        if (!pending.abort.signal.aborted && drafts[draftIndex]) {
+          drafts[draftIndex].postStateId = observation.stateId;
+        }
+      } catch (error) {
+        if (!isAbortError(error)) {
+          console.warn(
+            `[bsk record] post-action observation failed for step ${draftIndex + 1}`,
+            error,
+          );
+        }
+      } finally {
+        if (this.#pending.get(draftIndex) === pending) this.#pending.delete(draftIndex);
+      }
+    };
+    this.#queue = this.#queue.then(task, task).catch(() => {});
+  }
+
+  cancel(): void {
+    for (const pending of this.#pending.values()) pending.abort.abort();
+    this.#pending.clear();
+    this.clearRedirect();
+  }
+
+  async flush(): Promise<void> {
+    for (let round = 0; round < 10; round += 1) {
+      const current = this.#queue;
+      await current;
+      if (current === this.#queue) return;
+    }
+    console.warn("[bsk record] settle queue kept growing; using completed observations");
+  }
+
+  async settleTrailing(drafts: RecordingDraftStep[]): Promise<void> {
+    const trailing: RecordingDraftStep[] = [];
+    for (let index = drafts.length - 1; index >= 0; index -= 1) {
+      const draft = drafts[index];
+      if (!draft || draft.postStateId) break;
+      trailing.push(draft);
+    }
+    if (trailing.length === 0) return;
+    try {
+      const observation = await this.#captureWithRetry();
+      for (const draft of trailing) draft.postStateId = observation.stateId;
+    } catch (error) {
+      console.warn("[bsk record] final observation at stop failed", error);
+    }
+  }
+
+  clearRedirect(): void {
+    this.#pendingRedirect?.abort.abort();
+    this.#pendingRedirect = null;
+  }
+
+  scheduleRedirect(drafts: RecordingDraftStep[], url: string): void {
+    this.#pendingRedirect?.abort.abort();
+    const pending: PendingRedirect = { url, abort: new AbortController() };
+    this.#pendingRedirect = pending;
+    const task = () => this.#settleRedirect(drafts, pending);
+    this.#redirectQueue = this.#redirectQueue.then(task, task).catch(() => {});
+  }
+
+  async #settleRedirect(drafts: RecordingDraftStep[], pending: PendingRedirect): Promise<void> {
+    const outcome = await waitForDocumentSettled(this.#cdp, this.#rootScope, {
+      signal: pending.abort.signal,
+    });
+    if (outcome === "cancelled" || this.#pendingRedirect !== pending) return;
+
+    let finalUrl = pending.url;
+    try {
+      finalUrl = (await this.#tabsApi.get(this.#tabId)).url || finalUrl;
+    } catch {
+      // The navigation event URL remains the best available destination.
+    }
+    if (this.#pendingRedirect !== pending) return;
+    this.#pendingRedirect = null;
+    if (
+      !finalUrl ||
+      finalUrl === "about:blank" ||
+      this.#session.cursor.lastSettled?.url === finalUrl
+    ) {
+      return;
+    }
+
+    const last = drafts[drafts.length - 1];
+    if (last?.op === "navigate" && last.url === finalUrl) {
+      if (!last.postStateId) this.schedule(drafts, drafts.length - 1);
+      await this.flush();
+      return;
+    }
+
+    const draft: RecordingDraftStep = {
+      op: "navigate",
+      url: finalUrl,
+      pageUrl: finalUrl,
+      cause: "browser",
+      transitionQualifiers: ["server_redirect"],
+      preStateId: this.#session.cursor.lastSettled?.stateId,
+    };
+    drafts.push(draft);
+    const draftIndex = drafts.length - 1;
+    if (draft.preStateId) this.#session.registry.markStep(draft.preStateId, draftIndex + 1);
+    this.schedule(drafts, draftIndex);
+    await this.flush();
+  }
+
+  async flushRedirects(): Promise<void> {
+    for (let round = 0; round < 10; round += 1) {
+      const current = this.#redirectQueue;
+      await current;
+      if (current === this.#redirectQueue) return;
+    }
+    console.warn("[bsk record] redirect queue kept growing; using the final completed landing");
+  }
+}
@@ -0,0 +1,57 @@
+export interface RecordedStateEntry {
+  id: string;
+  url: string;
+  title?: string;
+  /** Rendered VOM text; capture indexes and source DOM/AX data never enter the registry. */
+  vomText: string;
+  truncated: boolean;
+  stepsHere: number[];
+}
+
+function stateIdentity(url: string, body: string): string {
+  return `${url}\0${body}`;
+}
+
+export class RecordingStateRegistry {
+  readonly #entriesById = new Map<string, RecordedStateEntry>();
+  readonly #idByIdentity = new Map<string, string>();
+  #nextId = 1;
+
+  register(input: {
+    url: string;
+    title?: string;
+    vomText: string;
+    truncated?: boolean;
+  }): RecordedStateEntry {
+    const identity = stateIdentity(input.url, input.vomText);
+    const existingId = this.#idByIdentity.get(identity);
+    if (existingId) {
+      const existing = this.#entriesById.get(existingId)!;
+      if (!existing.title && input.title) existing.title = input.title;
+      if (input.truncated) existing.truncated = true;
+      return existing;
+    }
+
+    const entry: RecordedStateEntry = {
+      id: `s${this.#nextId}`,
+      url: input.url,
+      ...(input.title ? { title: input.title } : {}),
+      vomText: input.vomText,
+      truncated: input.truncated ?? false,
+      stepsHere: [],
+    };
+    this.#nextId += 1;
+    this.#entriesById.set(entry.id, entry);
+    this.#idByIdentity.set(identity, entry.id);
+    return entry;
+  }
+
+  values(): RecordedStateEntry[] {
+    return [...this.#entriesById.values()];
+  }
+
+  markStep(stateId: string, draftId: number): void {
+    const entry = this.#entriesById.get(stateId);
+    if (entry && !entry.stepsHere.includes(draftId)) entry.stepsHere.push(draftId);
+  }
+}
@@ -0,0 +1,155 @@
+import type { RecordStepPayload } from "../record-bridge";
+import { hasRedirectQualifier } from "./navigation-policy";
+import type { RecordingDraftStep, TargetMatchHint } from "./types";
+
+export interface RecordingStepBuffer {
+  steps: RecordingDraftStep[];
+  navigation: RecordingNavigationCursor;
+}
+
+export interface RecordingNavigationCursor {
+  currentUrl?: string;
+  pendingNavigation: boolean;
+  pendingNavigationDeadline?: number;
+}
+
+const NAVIGATION_TRIGGER_WINDOW_MS = 3_000;
+
+function toDraftStep(
+  payload: RecordStepPayload,
+  targetHint?: TargetMatchHint,
+): RecordingDraftStep | null {
+  const pageUrl = payload.page_url;
+  const common = {
+    ...(pageUrl ? { pageUrl } : {}),
+    ...(targetHint ? { targetHint } : {}),
+  };
+  switch (payload.op) {
+    case "click":
+      return payload.target ? { op: "click", captureTarget: payload.target, ...common } : null;
+    case "hover":
+      return payload.target ? { op: "hover", captureTarget: payload.target, ...common } : null;
+    case "fill":
+      return payload.target
+        ? {
+            op: "fill",
+            captureTarget: payload.target,
+            value: payload.value ?? "",
+            ...(payload.commit ? { commit: payload.commit } : {}),
+            ...(payload.redacted ? { redacted: true } : {}),
+            ...common,
+          }
+        : null;
+    case "press":
+      return payload.key
+        ? {
+            op: "press",
+            key: payload.key,
+            ...(payload.target ? { captureTarget: payload.target } : {}),
+            ...(payload.modifiers?.length ? { modifiers: payload.modifiers } : {}),
+            ...common,
+          }
+        : null;
+    case "select":
+      return payload.target && payload.values
+        ? {
+            op: "select",
+            captureTarget: payload.target,
+            values: payload.values,
+            ...(payload.labels?.length ? { labels: payload.labels } : {}),
+            ...common,
+          }
+        : null;
+    case "navigate":
+      return null;
+  }
+}
+
+function annotateLastStepNavigation(buffer: RecordingStepBuffer, url: string): number {
+  for (let index = buffer.steps.length - 1; index >= 0; index -= 1) {
+    const step = buffer.steps[index];
+    if (!step) continue;
+    if (step.op === "click" || step.op === "press" || step.op === "select" || step.op === "fill") {
+      step.navigatedTo = url;
+      return index;
+    }
+    break;
+  }
+  return -1;
+}
+
+export type NavigationObserveResult =
+  | { kind: "noop" }
+  | { kind: "annotated"; index: number }
+  | { kind: "appended"; index: number }
+  | { kind: "coalesce_redirect"; url: string };
+
+export function observeRecordedNavigation(
+  buffer: RecordingStepBuffer,
+  url: string,
+  causedByAction?: boolean,
+  transitionType?: string,
+  transitionQualifiers?: string[],
+): NavigationObserveResult {
+  const navigation = buffer.navigation;
+  if (!url || url === navigation.currentUrl) return { kind: "noop" };
+  navigation.currentUrl = url;
+
+  const pendingIsCurrent =
+    navigation.pendingNavigation &&
+    (navigation.pendingNavigationDeadline === undefined ||
+      navigation.pendingNavigationDeadline >= Date.now());
+
+  if (causedByAction === true || (causedByAction === undefined && pendingIsCurrent)) {
+    navigation.pendingNavigation = false;
+    navigation.pendingNavigationDeadline = undefined;
+    const annotatedIndex = annotateLastStepNavigation(buffer, url);
+    if (annotatedIndex >= 0) return { kind: "annotated", index: annotatedIndex };
+  } else {
+    navigation.pendingNavigation = false;
+    navigation.pendingNavigationDeadline = undefined;
+  }
+
+  if (hasRedirectQualifier(transitionQualifiers)) {
+    return { kind: "coalesce_redirect", url };
+  }
+  buffer.steps.push({
+    op: "navigate",
+    url,
+    pageUrl: url,
+    transitionType,
+    transitionQualifiers,
+  });
+  return { kind: "appended", index: buffer.steps.length - 1 };
+}
+
+export function appendRecordedPayload(
+  buffer: RecordingStepBuffer,
+  payload: RecordStepPayload,
+  targetHint?: TargetMatchHint,
+): number | null {
+  if (payload.op === "navigate") {
+    if (!payload.url) return null;
+    const result = observeRecordedNavigation(
+      buffer,
+      payload.url,
+      payload.navigation_caused_by_action,
+      payload.transitionType,
+      payload.transitionQualifiers,
+    );
+    return result.kind === "appended" ? result.index : null;
+  }
+  const step = toDraftStep(
+    { ...payload, page_url: payload.page_url ?? buffer.navigation.currentUrl },
+    targetHint,
+  );
+  if (!step) return null;
+  buffer.steps.push(step);
+  if (step.op === "click" || step.op === "press" || step.op === "select" || step.op === "fill") {
+    buffer.navigation.pendingNavigation = payload.expects_navigation === true;
+    buffer.navigation.pendingNavigationDeadline = buffer.navigation.pendingNavigation
+      ? Date.now() + NAVIGATION_TRIGGER_WINDOW_MS
+      : undefined;
+  }
+  return buffer.steps.length - 1;
+}
@@ -0,0 +1,61 @@
+import type { RecordingNavigationCursor } from "./step-buffer";
+
+export interface TabActivation {
+  tabId: number;
+  revision: number;
+}
+
+export class RecordingTabCoordinator {
+  readonly #navigationByTab = new Map<number, RecordingNavigationCursor>();
+  #activeTabId: number;
+  #currentTabId: number;
+  #activationRevision = 0;
+
+  constructor(initialTabId: number, initialUrl?: string) {
+    this.#activeTabId = initialTabId;
+    this.#currentTabId = initialTabId;
+    this.#navigationByTab.set(initialTabId, {
+      currentUrl: initialUrl,
+      pendingNavigation: false,
+    });
+  }
+
+  get activeTabId(): number {
+    return this.#activeTabId;
+  }
+
+  get currentTabId(): number {
+    return this.#currentTabId;
+  }
+
+  noteActivation(tabId: number): TabActivation {
+    this.#activeTabId = tabId;
+    this.#activationRevision += 1;
+    return { tabId, revision: this.#activationRevision };
+  }
+
+  isLatest(activation: TabActivation): boolean {
+    return (
+      activation.tabId === this.#activeTabId && activation.revision === this.#activationRevision
+    );
+  }
+
+  commit(tabId: number, currentUrl?: string): void {
+    if (currentUrl !== undefined) this.navigation(tabId).currentUrl = currentUrl;
+    this.#currentTabId = tabId;
+  }
+
+  navigation(tabId: number, fallbackUrl?: string): RecordingNavigationCursor {
+    const existing = this.#navigationByTab.get(tabId);
+    if (existing) {
+      if (!existing.currentUrl && fallbackUrl) existing.currentUrl = fallbackUrl;
+      return existing;
+    }
+    const created: RecordingNavigationCursor = {
+      currentUrl: fallbackUrl,
+      pendingNavigation: false,
+    };
+    this.#navigationByTab.set(tabId, created);
+    return created;
+  }
+}
@@ -0,0 +1,86 @@
+import type { RenderedRef } from "@browser-skill/vom";
+import type { TargetDescriptorV3 } from "@/transport/types";
+import type { CaptureTargetDescriptor } from "../describe-target";
+import type { IndexedObservationNode, RegisteredObservation } from "./observation-capture";
+import type { TargetGeometry, TargetMatchHint } from "./types";
+
+const MATCH_TOLERANCE_PX = 2;
+
+function close(a: number, b: number): boolean {
+  return Math.abs(a - b) <= MATCH_TOLERANCE_PX;
+}
+
+function rectMatches(a: TargetGeometry["rect"], b: TargetGeometry["rect"]): boolean {
+  return close(a.x, b.x) && close(a.y, b.y) && close(a.w, b.w) && close(a.h, b.h);
+}
+
+function candidateMatches(
+  candidate: IndexedObservationNode,
+  geometry: TargetGeometry,
+  geometrySpace: "top" | "local",
+): boolean {
+  const rect = geometrySpace === "local" ? candidate.geometry.localRect : candidate.geometry.rect;
+  return rect != null && rectMatches(geometry.rect, rect);
+}
+
+export function unmatchedTarget(fallback?: CaptureTargetDescriptor): TargetDescriptorV3 {
+  return {
+    ...(fallback?.role ? { role: fallback.role } : {}),
+    ...(fallback?.name ? { name: fallback.name } : {}),
+    unmatched: true,
+  };
+}
+
+function normalized(value: string | undefined): string {
+  return value?.replace(/\s+/g, " ").trim().toLowerCase() ?? "";
+}
+
+function matchesSemantics(ref: RenderedRef, fallback?: CaptureTargetDescriptor): boolean {
+  const role = normalized(fallback?.role);
+  const name = normalized(fallback?.name);
+  if (!role && !name) return false;
+  if (role && normalized(ref.role) !== role) return false;
+  if (name && normalized(ref.name) !== name) return false;
+  return true;
+}
+
+function descriptor(ref: RenderedRef): TargetDescriptorV3 {
+  return {
+    ref: ref.ref,
+    ...(ref.role ? { role: ref.role } : {}),
+    ...(ref.name ? { name: ref.name } : {}),
+    ...(ref.ctx ? { ctx: ref.ctx } : {}),
+  };
+}
+
+export function matchObservationTarget(input: {
+  observation: RegisteredObservation;
+  hint?: TargetMatchHint;
+  fallback?: CaptureTargetDescriptor;
+}): TargetDescriptorV3 {
+  if (input.hint?.frameId === null) return unmatchedTarget(input.fallback);
+  const frameId = input.hint?.frameId ?? input.observation.rootFrameId;
+  const geometry = input.hint?.geometry;
+  if (geometry) {
+    const matches = input.observation.index
+      .candidates(frameId, geometry.tag)
+      .filter(
+        (candidate) =>
+          candidate.ref &&
+          candidateMatches(candidate, geometry, input.hint?.geometrySpace ?? "top"),
+      );
+    if (matches.length === 1) return descriptor(matches[0]!.ref!);
+    const semanticMatches = matches.filter(
+      (candidate) => candidate.ref && matchesSemantics(candidate.ref, input.fallback),
+    );
+    if (semanticMatches.length === 1) return descriptor(semanticMatches[0]!.ref!);
+    return unmatchedTarget(input.fallback);
+  }
+
+  const semanticMatches = input.observation.index
+    .refs(frameId)
+    .filter((ref) => matchesSemantics(ref, input.fallback));
+  return semanticMatches.length === 1
+    ? descriptor(semanticMatches[0]!)
+    : unmatchedTarget(input.fallback);
+}
@@ -0,0 +1,92 @@
+import {
+  type StepV3,
+  type StopReason,
+  TRACE_VERSION_V3,
+  type TraceStateV3,
+  type TraceV3,
+  VOM_FORMAT_VERSION,
+} from "@/transport/types";
+import { resolveDraftStartUrl } from "./draft-policy";
+import type { RecordedStateEntry, RecordingStateRegistry } from "./state-registry";
+import { reduceTraceStepsV3 } from "./trace-reducer-v3";
+import { formatTraceStateBody } from "./trace-state-body";
+import type { RecordingDraftStep, StepAnnotation } from "./types";
+
+function publishedEntries(registry: RecordingStateRegistry, steps: StepV3[]): RecordedStateEntry[] {
+  const entries = registry.values();
+  if (steps.length === 0) return entries.slice(0, 1);
+  const referenced = new Set(steps.flatMap((step) => [step.state, step.result.state]));
+  return entries.filter((entry) => referenced.has(entry.id));
+}
+
+function remapDraftIds(draftIds: number[], stepIdByDraftId: Map<number, number>): number[] {
+  return [
+    ...new Set(
+      draftIds.flatMap((id) => {
+        const stepId = stepIdByDraftId.get(id);
+        return stepId === undefined ? [] : [stepId];
+      }),
+    ),
+  ].sort((a, b) => a - b);
+}
+
+export function buildTraceV3(input: {
+  registry: RecordingStateRegistry;
+  drafts: RecordingDraftStep[];
+  annotations?: StepAnnotation[];
+  startedAt: string;
+  purpose?: string;
+  startUrl?: string;
+  stoppedBy: StopReason;
+  bskVersion: string;
+  redactValues?: boolean;
+  includeTabSwitches?: boolean;
+}): TraceV3 {
+  const reduced = reduceTraceStepsV3(input.drafts, {
+    includeTabSwitches: input.includeTabSwitches,
+    redactValues: input.redactValues,
+  });
+  const entries = publishedEntries(input.registry, reduced.steps);
+  const publishedId = new Map(entries.map((entry, index) => [entry.id, `s${index + 1}`]));
+  const annotationsByState = new Map<string, StepAnnotation[]>();
+  for (const annotation of input.annotations ?? []) {
+    const bucket = annotationsByState.get(annotation.stateId) ?? [];
+    bucket.push(annotation);
+    annotationsByState.set(annotation.stateId, bucket);
+  }
+  const steps = reduced.steps.map((step) => ({
+    ...step,
+    state: publishedId.get(step.state) ?? step.state,
+    result: { state: publishedId.get(step.result.state) ?? step.result.state },
+  }));
+  const states: TraceStateV3[] = entries.map((entry) => {
+    const id = publishedId.get(entry.id) ?? entry.id;
+    return {
+      id,
+      url: entry.url,
+      ...(entry.title ? { title: entry.title } : {}),
+      body: formatTraceStateBody({
+        stateId: id,
+        url: entry.url,
+        title: entry.title,
+        stepIds: remapDraftIds(entry.stepsHere, reduced.stepIdByDraftId),
+        vomText: entry.vomText,
+        annotations: annotationsByState.get(entry.id) ?? [],
+        stepIdByDraftId: reduced.stepIdByDraftId,
+      }),
+      ...(entry.truncated ? { truncated: true } : {}),
+    };
+  });
+
+  return {
+    version: TRACE_VERSION_V3,
+    ...(input.purpose ? { purpose: input.purpose } : {}),
+    recorded_at: new Date().toISOString(),
+    started_at: input.startedAt,
+    stopped_by: input.stoppedBy,
+    entry: { start_url: resolveDraftStartUrl(input.drafts, input.startUrl, states[0]?.url) },
+    recorder: { bsk: input.bskVersion, vom: VOM_FORMAT_VERSION },
+    states,
+    steps,
+  };
+}
@@ -1,30 +1,10 @@
-import type { DraftTraceStep, PageRef, SelectedOption, Step } from "@/transport/types";
-
-const CLIPBOARD_KEYS = new Set(["a", "c", "v", "x", "A", "C", "V", "X"]);
-const MODIFIER_ONLY_KEYS = new Set(["Meta", "Control", "Alt", "Shift", "OS", "Hyper", "Super"]);
-
-export function shouldRecordPress(
-  key: string,
-  modifiers?: Array<"alt" | "ctrl" | "meta" | "shift">,
-): boolean {
-  if (MODIFIER_ONLY_KEYS.has(key)) return false;
-  const mods = modifiers ?? [];
-  const hasCtrlOrMeta = mods.includes("ctrl") || mods.includes("meta");
-  if (hasCtrlOrMeta && CLIPBOARD_KEYS.has(key)) return false;
-  if (key === "Enter" || key === "Escape") return true;
-  // Drop bare character typing — FillSession already records the value.
-  if (key.length === 1 && !hasCtrlOrMeta && !mods.includes("alt")) return false;
-  return false;
-}
-
-function shouldIncludeDraft(step: DraftTraceStep): boolean {
-  if (step.op === "press" && !shouldRecordPress(step.key, step.modifiers)) return false;
-  return true;
-}
+import type { PageRefV2, SelectedOptionV2, StepV2, TraceV2 } from "@/transport/types";
+import { resolveDraftStartUrl, shouldIncludeDraft } from "./draft-policy";
+import type { RecordingDraftStep } from "./types";

 /** Collapse consecutive navigations to the last hop. */
-function collapseNavigations(steps: DraftTraceStep[]): DraftTraceStep[] {
-  const out: DraftTraceStep[] = [];
+function collapseNavigations(steps: RecordingDraftStep[]): RecordingDraftStep[] {
+  const out: RecordingDraftStep[] = [];
  for (const step of steps) {
    const prev = out[out.length - 1];
    if (step.op === "navigate" && prev?.op === "navigate") {
@@ -36,7 +16,7 @@ function collapseNavigations(steps: DraftTraceStep[]): DraftTraceStep[] {
  return out;
 }

-function collectUrls(steps: DraftTraceStep[], startUrl?: string): string[] {
+function collectUrls(steps: RecordingDraftStep[], startUrl?: string): string[] {
  const urls: string[] = [];
  if (startUrl) urls.push(startUrl);
  for (const step of steps) {
@@ -44,8 +24,8 @@ function collectUrls(steps: DraftTraceStep[], startUrl?: string): string[] {
      urls.push(step.url);
      continue;
    }
-    if ("page_url" in step && step.page_url) urls.push(step.page_url);
-    if ("navigated_to" in step && step.navigated_to) urls.push(step.navigated_to);
+    if (step.pageUrl) urls.push(step.pageUrl);
+    if ("navigatedTo" in step && step.navigatedTo) urls.push(step.navigatedTo);
  }
  const seen = new Set<string>();
  const unique: string[] = [];
@@ -58,9 +38,9 @@ function collectUrls(steps: DraftTraceStep[], startUrl?: string): string[] {
 }

 function buildPageRegistry(
-  steps: DraftTraceStep[],
+  steps: RecordingDraftStep[],
  startUrl?: string,
-): { pages: PageRef[]; urlToId: Map<string, string> } {
+): { pages: PageRefV2[]; urlToId: Map<string, string> } {
  const urls = collectUrls(steps, startUrl);
  const urlToId = new Map<string, string>();
  const pages = urls.map((url, index) => {
@@ -81,28 +61,28 @@ function pageIdFor(
  return urlToId.values().next().value ?? "p1";
 }

-function pageUrlForDraft(step: DraftTraceStep, fallbackUrl?: string): string | undefined {
-  if (step.op === "navigate") return step.page_url ?? step.url;
-  if ("page_url" in step && step.page_url) return step.page_url;
+function pageUrlForDraft(step: RecordingDraftStep, fallbackUrl?: string): string | undefined {
+  if (step.op === "navigate") return step.pageUrl ?? step.url;
+  if (step.pageUrl) return step.pageUrl;
  return fallbackUrl;
 }

 function effectForNavigation(
  navigatedTo: string | undefined,
  urlToId: Map<string, string>,
-): Step["effect"] {
+): StepV2["effect"] {
  if (!navigatedTo) return undefined;
  const pageId = urlToId.get(navigatedTo);
  if (!pageId) return undefined;
  return { navigated_to: pageId };
 }

-function withEffect(step: Step, effect: Step["effect"]): Step {
+function withEffect(step: StepV2, effect: StepV2["effect"]): StepV2 {
  if (!effect) return step;
  return { ...step, effect };
 }

-function toSelection(values: string[], labels?: string[]): SelectedOption[] {
+function toSelection(values: string[], labels?: string[]): SelectedOptionV2[] {
  return values.map((value, index) => ({
    value,
    ...(labels?.[index] ? { label: labels[index] } : {}),
@@ -110,11 +90,11 @@ function toSelection(values: string[], labels?: string[]): SelectedOption[] {
 }

 function toV2Step(
-  step: DraftTraceStep,
+  step: RecordingDraftStep,
  id: number,
  urlToId: Map<string, string>,
  fallbackUrl?: string,
-): Step | null {
+): StepV2 | null {
  if (!shouldIncludeDraft(step)) return null;

  const pageUrl = pageUrlForDraft(step, fallbackUrl);
@@ -129,28 +109,23 @@ function toV2Step(
        to: step.url,
      };
    case "click":
+      if (!step.captureTarget) return null;
      return withEffect(
        {
          op: "click",
          id,
          page,
-          target: step.target,
+          target: step.captureTarget,
        },
-        effectForNavigation(step.navigated_to, urlToId),
+        effectForNavigation(step.navigatedTo, urlToId),
      );
-    case "hover":
-      return {
-        op: "hover",
-        id,
-        page,
-        target: step.target,
-      };
    case "fill":
+      if (!step.captureTarget) return null;
      return {
        op: "fill",
        id,
        page,
-        target: step.target,
+        target: step.captureTarget,
        value: step.value,
        ...(step.redacted ? { redacted: true } : {}),
      };
@@ -161,44 +136,51 @@ function toV2Step(
          id,
          page,
          key: step.key,
-          ...(step.target ? { target: step.target } : {}),
+          ...(step.captureTarget ? { target: step.captureTarget } : {}),
          ...(step.modifiers?.length ? { modifiers: step.modifiers } : {}),
        },
-        effectForNavigation(step.navigated_to, urlToId),
+        effectForNavigation(step.navigatedTo, urlToId),
      );
    case "select":
+      if (!step.captureTarget) return null;
      return withEffect(
        {
          op: "select",
          id,
          page,
-          target: step.target,
+          target: step.captureTarget,
          selection: toSelection(step.values, step.labels),
        },
-        effectForNavigation(step.navigated_to, urlToId),
+        effectForNavigation(step.navigatedTo, urlToId),
      );
+    // `hover` only exists in Trace v3. Peers that negotiate v2 predate the
+    // step variant and fail to decode the whole result if we emit it.
+    case "hover":
+    case "scroll":
+    case "switch_tab":
+      return null;
  }
 }

-export interface ReducedTrace {
-  pages: PageRef[];
-  steps: Step[];
+interface ReducedTrace {
+  pages: PageRefV2[];
+  steps: StepV2[];
 }

 /**
 * Compile capture drafts into record-only trace v2 steps.
 * Variable inputs are NOT classified here — executing agents infer that at run time.
 */
-export function reduceTraceSteps(steps: DraftTraceStep[], startUrl?: string): ReducedTrace {
+function reduceTraceSteps(steps: RecordingDraftStep[], startUrl?: string): ReducedTrace {
  const collapsed = collapseNavigations(steps);
  const { pages, urlToId } = buildPageRegistry(collapsed, startUrl);
-  const out: Step[] = [];
+  const out: StepV2[] = [];
  let id = 1;
  let lastUrl = startUrl;
  for (const draft of collapsed) {
    if (draft.op === "navigate") lastUrl = draft.url;
-    else if ("navigated_to" in draft && draft.navigated_to) lastUrl = draft.navigated_to;
-    else if ("page_url" in draft && draft.page_url) lastUrl = draft.page_url;
+    else if ("navigatedTo" in draft && draft.navigatedTo) lastUrl = draft.navigatedTo;
+    else if (draft.pageUrl) lastUrl = draft.pageUrl;
    const step = toV2Step(draft, id, urlToId, lastUrl);
    if (!step) continue;
    out.push(step);
@@ -207,18 +189,27 @@ export function reduceTraceSteps(steps: DraftTraceStep[], startUrl?: string): Re
  return { pages, steps: out };
 }

-export function resolveTraceStartUrl(
-  drafts: DraftTraceStep[],
+function resolveTraceStartUrl(
+  drafts: RecordingDraftStep[],
  startUrl?: string,
-  pages?: PageRef[],
+  pages?: PageRefV2[],
 ): string {
-  if (startUrl) return startUrl;
-  const navigate = drafts.find((step): step is Extract<DraftTraceStep, { op: "navigate" }> => {
-    return step.op === "navigate";
-  });
-  if (navigate) return navigate.url;
-  for (const draft of drafts) {
-    if ("page_url" in draft && draft.page_url) return draft.page_url;
-  }
-  return pages?.[0]?.url ?? "about:blank";
+  return resolveDraftStartUrl(drafts, startUrl, pages?.[0]?.url);
+}
+
+export function buildTraceV2(input: {
+  steps: RecordingDraftStep[];
+  startedAt: string;
+  startUrl?: string;
+  purpose?: string;
+}): TraceV2 {
+  const { pages, steps } = reduceTraceSteps(input.steps, input.startUrl);
+  return {
+    recorded_at: new Date().toISOString(),
+    started_at: input.startedAt,
+    ...(input.purpose ? { purpose: input.purpose } : {}),
+    entry: { start_url: resolveTraceStartUrl(input.steps, input.startUrl, pages) },
+    pages,
+    steps,
+  };
 }
@@ -0,0 +1,154 @@
+import type { NavigationCause, StepV3 } from "@/transport/types";
+import { shouldIncludeDraft } from "./draft-policy";
+import { hasRedirectQualifier } from "./navigation-policy";
+import { unmatchedTarget } from "./target-matcher";
+import type { RecordingDraftStep } from "./types";
+
+interface CollapsedDraft {
+  draft: RecordingDraftStep;
+  draftIds: number[];
+}
+
+const TRANSITION_CAUSES: Record<string, NavigationCause> = {
+  typed: "user_typed",
+  generated: "user_typed",
+  keyword: "user_typed",
+  keyword_generated: "user_typed",
+  link: "link",
+  form_submit: "form_submit",
+  reload: "reload",
+  auto_bookmark: "browser",
+  start_page: "browser",
+};
+
+function isRedirect(step: Extract<RecordingDraftStep, { op: "navigate" }>): boolean {
+  return hasRedirectQualifier(step.transitionQualifiers);
+}
+
+function collapseRedirects(steps: RecordingDraftStep[]): CollapsedDraft[] {
+  const output: CollapsedDraft[] = [];
+  steps.forEach((step, index) => {
+    const previous = output[output.length - 1];
+    if (step.op === "navigate" && previous?.draft.op === "navigate" && isRedirect(step)) {
+      previous.draft = {
+        ...previous.draft,
+        url: step.url,
+        postStateId: step.postStateId ?? previous.draft.postStateId,
+      };
+      previous.draftIds.push(index + 1);
+      return;
+    }
+    output.push({ draft: { ...step }, draftIds: [index + 1] });
+  });
+  return output;
+}
+
+function navigationCause(step: Extract<RecordingDraftStep, { op: "navigate" }>): NavigationCause {
+  if (step.cause) return step.cause;
+  const qualifiers = step.transitionQualifiers ?? [];
+  if (qualifiers.includes("forward_back")) return "history";
+  if (qualifiers.includes("from_address_bar")) return "user_typed";
+  return TRANSITION_CAUSES[step.transitionType ?? ""] ?? "browser";
+}
+
+function selection(values: string[], labels?: string[]): Array<{ value: string; label?: string }> {
+  return values.map((value, index) => ({
+    value,
+    ...(labels?.[index] ? { label: labels[index] } : {}),
+  }));
+}
+
+interface ReduceDraftOptions {
+  includeTabSwitches: boolean;
+  redactValues: boolean;
+}
+
+function reduceDraft(
+  draft: RecordingDraftStep,
+  id: number,
+  options: ReduceDraftOptions,
+): StepV3 | null {
+  if (!shouldIncludeDraft(draft)) return null;
+  if (draft.op === "switch_tab") {
+    if (!options.includeTabSwitches || !draft.preStateId || !draft.postStateId) return null;
+    return {
+      op: "switch_tab",
+      id,
+      state: draft.preStateId,
+      result: { state: draft.postStateId },
+    };
+  }
+  const state = draft.preStateId ?? draft.postStateId;
+  const resultState = draft.postStateId ?? draft.preStateId;
+  if (!state || !resultState) return null;
+  const common = { id, state, result: { state: resultState } };
+
+  switch (draft.op) {
+    case "navigate":
+      return { op: "navigate", ...common, to: draft.url, cause: navigationCause(draft) };
+    case "click":
+      return {
+        op: "click",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+      };
+    case "hover":
+      return {
+        op: "hover",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+      };
+    case "fill":
+      const fillIsRedacted = options.redactValues || draft.redacted === true;
+      return {
+        op: "fill",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+        value: fillIsRedacted ? "***" : draft.value,
+        commit: draft.commit ?? "blur",
+        ...(fillIsRedacted ? { redacted: true } : {}),
+      };
+    case "press":
+      return {
+        op: "press",
+        ...common,
+        key: draft.key,
+        ...(draft.captureTarget || draft.matchedTarget
+          ? { target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget) }
+          : {}),
+        ...(draft.modifiers?.length ? { modifiers: draft.modifiers } : {}),
+      };
+    case "select":
+      return {
+        op: "select",
+        ...common,
+        target: draft.matchedTarget ?? unmatchedTarget(draft.captureTarget),
+        ...(!options.redactValues ? { selection: selection(draft.values, draft.labels) } : {}),
+      };
+    case "scroll":
+      return { op: "scroll", ...common };
+  }
+}
+
+export interface ReducedTraceV3 {
+  steps: StepV3[];
+  stepIdByDraftId: Map<number, number>;
+}
+
+export function reduceTraceStepsV3(
+  steps: RecordingDraftStep[],
+  options: { includeTabSwitches?: boolean; redactValues?: boolean } = {},
+): ReducedTraceV3 {
+  const output: StepV3[] = [];
+  const stepIdByDraftId = new Map<number, number>();
+  for (const { draft, draftIds } of collapseRedirects(steps)) {
+    const step = reduceDraft(draft, output.length + 1, {
+      includeTabSwitches: options.includeTabSwitches === true,
+      redactValues: options.redactValues === true,
+    });
+    if (!step) continue;
+    output.push(step);
+    for (const draftId of draftIds) stepIdByDraftId.set(draftId, step.id);
+  }
+  return { steps: output, stepIdByDraftId };
+}
@@ -0,0 +1,39 @@
+import type { StepAnnotation } from "./types";
+
+function annotationText(annotation: StepAnnotation, stepId: number): string {
+  return ` ⟵ step ${stepId}: ${annotation.op}${annotation.detail ? `: ${annotation.detail}` : ""}`;
+}
+
+export function formatTraceStateBody(input: {
+  stateId: string;
+  url: string;
+  title?: string;
+  stepIds: number[];
+  vomText: string;
+  annotations: StepAnnotation[];
+  stepIdByDraftId: Map<number, number>;
+}): string {
+  const lines = ["# bsk-observation 1", `state: ${JSON.stringify(input.stateId)}`];
+  lines.push(`url: ${JSON.stringify(input.url)}`);
+  if (input.title) lines.push(`title: ${JSON.stringify(input.title)}`);
+  if (input.stepIds.length > 0) lines.push(`steps_here: [${input.stepIds.join(", ")}]`);
+  lines.push("---");
+
+  const byLine = new Map<number, Array<{ annotation: StepAnnotation; stepId: number }>>();
+  for (const annotation of input.annotations) {
+    const stepId = input.stepIdByDraftId.get(annotation.draftId);
+    if (stepId === undefined) continue;
+    const bucket = byLine.get(annotation.line) ?? [];
+    bucket.push({ annotation, stepId });
+    byLine.set(annotation.line, bucket);
+  }
+
+  input.vomText.split("\n").forEach((bodyLine, lineIndex) => {
+    let line = bodyLine;
+    for (const item of byLine.get(lineIndex) ?? []) {
+      line += annotationText(item.annotation, item.stepId);
+    }
+    lines.push(line);
+  });
+  return `${lines.join("\n")}\n`;
+}
@@ -0,0 +1,85 @@
+import type { CaptureTargetDescriptor } from "@/lib/describe-target";
+import type {
+  FillCommit,
+  KeyModifier,
+  NavigationCause,
+  StepV3,
+  TargetDescriptorV3,
+} from "@/transport/types";
+
+export interface TargetGeometry {
+  /** Top-level viewport-relative CSS pixels, as defined by the geometry module. */
+  rect: { x: number; y: number; w: number; h: number };
+  tag: string;
+}
+
+export interface TargetMatchHint {
+  geometry?: TargetGeometry;
+  /** Missing means top frame; null means the source Document could not be resolved. */
+  frameId?: string | null;
+  geometrySpace?: "top" | "local";
+}
+
+export interface StepAnnotation {
+  draftId: number;
+  op: StepV3["op"];
+  line: number;
+  stateId: string;
+  detail?: string;
+}
+
+interface DraftStateLink {
+  pageUrl?: string;
+  preStateId?: string;
+  postStateId?: string;
+}
+
+interface DraftTarget {
+  captureTarget?: CaptureTargetDescriptor;
+  targetHint?: TargetMatchHint;
+  matchedTarget?: TargetDescriptorV3;
+}
+
+interface DraftNavigationEffect {
+  navigatedTo?: string;
+}
+
+export type RecordingDraftStep =
+  | ({ op: "click" } & DraftStateLink & DraftTarget & DraftNavigationEffect)
+  | ({ op: "hover" } & DraftStateLink & DraftTarget)
+  | ({
+      op: "fill";
+      value: string;
+      commit?: FillCommit;
+      redacted?: boolean;
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({
+      op: "press";
+      key: string;
+      modifiers?: KeyModifier[];
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({
+      op: "select";
+      values: string[];
+      labels?: string[];
+    } & DraftStateLink &
+      DraftTarget &
+      DraftNavigationEffect)
+  | ({ op: "scroll" } & DraftStateLink)
+  | ({ op: "switch_tab" } & DraftStateLink)
+  | ({
+      op: "navigate";
+      url: string;
+      cause?: NavigationCause;
+      transitionType?: string;
+      transitionQualifiers?: string[];
+    } & DraftStateLink);
+
+export type TargetedRecordingDraft = Extract<
+  RecordingDraftStep,
+  { op: "click" | "hover" | "fill" | "press" | "select" }
+>;
@@ -0,0 +1,22 @@
+export const RECORD_DOCUMENT_ATTRIBUTE = "data-bsk-record-document";
+
+const RECORDING_DOCUMENT_ID_PATTERN =
+  /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
+const RECORDING_DOCUMENT_MARKER_PREFIX = "bsk:";
+
+export function recordingDocumentMarkerValue(identity: string): string {
+  if (!RECORDING_DOCUMENT_ID_PATTERN.test(identity)) {
+    throw new TypeError("recording Document identity must be a random UUID");
+  }
+  return `${RECORDING_DOCUMENT_MARKER_PREFIX}${identity}`;
+}
+
+/** Read BrowserSkill's opaque per-Document recording identity from captured attributes. */
+export function readRecordingDocumentIdentity(
+  attrs: Readonly<Record<string, string>>,
+): string | undefined {
+  const marker = attrs[RECORD_DOCUMENT_ATTRIBUTE];
+  if (!marker?.startsWith(RECORDING_DOCUMENT_MARKER_PREFIX)) return undefined;
+  const identity = marker.slice(RECORDING_DOCUMENT_MARKER_PREFIX.length);
+  return identity && RECORDING_DOCUMENT_ID_PATTERN.test(identity) ? identity : undefined;
+}
@@ -127,6 +127,38 @@ describe("requestBorrowConfirmation", () => {
    expect(message.requestId.length).toBeGreaterThan(0);
  });

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

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

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

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

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

+  it("bypasses and restores the control overlay for an upload trigger click", async () => {
+    const sendMessage = vi.fn(async () => undefined);
+    vi.stubGlobal("chrome", {
+      tabs: {
+        get: vi.fn(async () => ({ id: 7, windowId: 4242, active: true })),
+        query: vi.fn(async () => [{ id: 7, windowId: 4242, active: true }]),
+        sendMessage,
+      },
+    });
+    const { transport, sent, deliver } = fakeTransport();
+    const sessions = new SessionManager({
+      agentWindow: {
+        create: vi.fn(async () => 4242),
+        remove: vi.fn(async () => {}),
+        ensureActiveTab: vi.fn(async () => {}),
+      },
+    });
+    const ctx = await sessions.start("aa11");
+    ctx.refStore.set("e1", 123, { tabId: 7 });
+    const send = vi.fn(async <T>(_tabId: number, method: string, params?: object) => {
+      if (method === "Page.getLayoutMetrics") {
+        return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } } as T;
+      }
+      if (method === "DOM.getContentQuads") {
+        return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] } as T;
+      }
+      if (method === "DOM.resolveNode") {
+        return { object: { objectId: "trigger-object" } } as T;
+      }
+      if (method === "DOM.describeNode") return { node: { backendNodeId: 456 } } as T;
+      if (method === "Runtime.callFunctionOn") {
+        const declaration = (params as { functionDeclaration?: string }).functionDeclaration ?? "";
+        if (declaration.includes("count: state.inputs.length")) {
+          return { result: { value: { count: 1, multiple: false } } } as T;
+        }
+        if (declaration.includes("inputs[0]")) {
+          return { result: { objectId: "input-object" } } as T;
+        }
+        return { result: { value: true } } as T;
+      }
+      if (method === "Runtime.evaluate") {
+        const expression = (params as { expression?: string }).expression ?? "";
+        if (expression.includes("overlayDetails")) {
+          return { result: { value: { hitIndex: 0 } } } as T;
+        }
+        if (expression.includes("overlayHostPresent")) {
+          return {
+            result: {
+              value: { overlayHostPresent: true, overlayHostConnected: true },
+            },
+          } as T;
+        }
+        if (expression.includes("count:")) {
+          return { result: { value: { count: 1, multiple: false } } } as T;
+        }
+        if (expression.includes("?.inputs[0]")) {
+          return { result: { objectId: "input-object" } } as T;
+        }
+        return { result: { value: true } } as T;
+      }
+      return {} as T;
+    });
+    const cdp = {
+      send,
+      detachSession: vi.fn(async () => {}),
+      ensureNetworkCapture: vi.fn(async () => {}),
+      networkEntriesSince: vi.fn(() => ({
+        tab_id: 7,
+        entries: [],
+        next_since: 0,
+        truncated: false,
+      })),
+      setDeviceMetricsOverride: vi.fn(async () => {}),
+      clearDeviceMetricsOverride: vi.fn(async () => {}),
+      setUserAgentOverride: vi.fn(async () => {}),
+      setTouchEmulationEnabled: vi.fn(async () => {}),
+    };
+    const dispatcher = new ToolDispatcher({ transport, sessions, cdp: cdp as TestDispatcherCdp });
+    dispatcher.start();
+
+    deliver(
+      makeRequest("tool.upload", {
+        session_id: "aa11",
+        ref: "@e1",
+        files: [{ transfer_id: "tr_1", name: "test.png", staged_path: "/stage/test.png" }],
+      }),
+    );
+    await flushMicrotasks();
+    await vi.waitFor(() => expect(sent).toHaveLength(1));
+
+    expect(sent[0]).toMatchObject({ result: { tab_id: 7, file_names: ["test.png"] } });
+    expect(sendMessage).toHaveBeenNthCalledWith(1, 7, {
+      type: "bh-automation-bypass",
+      enabled: true,
+    });
+    expect(sendMessage).toHaveBeenNthCalledWith(2, 7, {
+      type: "bh-automation-bypass",
+      enabled: false,
+    });
+  });
+
  it("detaches CDP state before stopping a session", async () => {
    const { transport, sent, deliver } = fakeTransport();
    const sessions = new SessionManager({
@@ -203,6 +368,55 @@ describe("ToolDispatcher", () => {
    expect(sent[0]).toEqual({ id: "r-1", result: {} });
  });

+  it("forwards daemon cancellation into an in-flight session stop", async () => {
+    const { transport, sent, deliver } = fakeTransport();
+    const remove = vi.fn(async () => {});
+    const sessions = new SessionManager({
+      agentWindow: {
+        create: vi.fn(async () => 4242),
+        remove,
+        ensureActiveTab: vi.fn(async () => {}),
+      },
+    });
+    await sessions.start("aa11");
+    let finishDetach: () => void = () => {};
+    const detach = new Promise<void>((resolve) => {
+      finishDetach = resolve;
+    });
+    const cdp = {
+      send: vi.fn(),
+      detachSession: vi.fn(() => detach),
+      ensureNetworkCapture: vi.fn(async () => {}),
+      networkEntriesSince: vi.fn(() => ({
+        tab_id: 7,
+        entries: [],
+        next_since: 0,
+        truncated: false,
+      })),
+      setDeviceMetricsOverride: vi.fn(async () => {}),
+      clearDeviceMetricsOverride: vi.fn(async () => {}),
+      setUserAgentOverride: vi.fn(async () => {}),
+      setTouchEmulationEnabled: vi.fn(async () => {}),
+    };
+    const dispatcher = new ToolDispatcher({ transport, sessions, cdp: cdp as TestDispatcherCdp });
+    dispatcher.start();
+
+    deliver(makeRequest("tool.session_stop", { session_id: "aa11" }));
+    await vi.waitFor(() => expect(cdp.detachSession).toHaveBeenCalledWith("aa11"));
+    deliver({ id: "cancel-stop", method: "cancel", params: { rpc_id: "r-1" } });
+    await flushMicrotasks();
+    finishDetach();
+    await flushMicrotasks();
+
+    expect(sent).toContainEqual({ id: "cancel-stop", result: { cancelled: true } });
+    expect(sent).toContainEqual({
+      id: "r-1",
+      error: expect.objectContaining({ code: "cancelled" }),
+    });
+    expect(sessions.has("aa11")).toBe(true);
+    expect(remove).not.toHaveBeenCalled();
+  });
+
  it("returns not_found when stopping an unknown session", async () => {
    const { transport, sent, deliver } = fakeTransport();
    const sessions = new SessionManager({
@@ -0,0 +1,988 @@
+import { describe, expect, it, vi } from "vitest";
+import { SessionManager } from "@/session-manager/manager";
+import { type DownloadsApi, handleDownload } from "../download";
+import { captureBrowserDownload } from "../download-capture";
+import { uploadThroughFileDrop } from "../file-drop-transaction";
+import { uploadThroughActivatedFileInput } from "../file-input-transaction";
+import type { ResolvedActionTarget } from "../interaction";
+import type { CdpRunner } from "../shared";
+import { handleUpload } from "../upload";
+
+function sessions() {
+  return new SessionManager({
+    agentWindow: {
+      create: vi.fn(async () => 100),
+      remove: vi.fn(async () => {}),
+      ensureActiveTab: vi.fn(async () => {}),
+    },
+  });
+}
+
+function tabsApi() {
+  return {
+    get: vi.fn(
+      async (tabId: number) => ({ id: tabId, windowId: 100, active: true }) as chrome.tabs.Tab,
+    ),
+    query: vi.fn(async () => [{ id: 4, windowId: 100, active: true } as chrome.tabs.Tab]),
+  };
+}
+
+function fakeEvent<T extends (...args: never[]) => unknown>() {
+  const listeners = new Set<T>();
+  return {
+    addListener: (listener: T) => listeners.add(listener),
+    removeListener: (listener: T) => listeners.delete(listener),
+    emit: (...args: Parameters<T>) => {
+      for (const listener of listeners) listener(...args);
+    },
+  };
+}
+
+function actionTarget(frameId?: string, sessionId?: string): ResolvedActionTarget {
+  return {
+    tab: { tabId: 4, windowId: 100, active: true },
+    backendNodeId: 123,
+    cdpTarget: { tabId: 4, ...(sessionId ? { sessionId } : {}) },
+    ...(frameId ? { frameId } : {}),
+    usedRef: "e3",
+  };
+}
+
+function withoutOverlay<T>(operation: () => Promise<T>): Promise<T> {
+  return operation();
+}
+
+function uploadCdp(
+  options: {
+    inputCount?: number;
+    multiple?: boolean;
+    chooser?: { frameId?: string; backendNodeId?: number; mode?: string };
+    pendingResolve?: boolean;
+  } = {},
+) {
+  const calls: Array<{ method: string; params?: object }> = [];
+  let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+  const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
+    calls.push({ method, params });
+    if (method === "DOM.scrollIntoViewIfNeeded") return {};
+    if (method === "Page.setInterceptFileChooserDialog") return {};
+    if (method === "Page.getLayoutMetrics")
+      return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+    if (method === "DOM.getContentQuads") return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] };
+    if (method === "DOM.resolveNode") {
+      if (options.pendingResolve) return new Promise<never>(() => {});
+      return { object: { objectId: "trigger-object" } };
+    }
+    if (method === "Runtime.callFunctionOn") {
+      const declaration = (params as { functionDeclaration?: string }).functionDeclaration ?? "";
+      if (declaration.includes("Object.defineProperty")) return { result: { value: true } };
+      if (declaration.includes("count: state.inputs.length")) {
+        return {
+          result: {
+            value: {
+              count: options.inputCount ?? 1,
+              multiple: options.multiple ?? true,
+            },
+          },
+        };
+      }
+      if (declaration.includes("inputs[0]")) {
+        return { result: { objectId: "input-object" } };
+      }
+      return { result: { value: true } };
+    }
+    if (method === "DOM.describeNode") return { node: { backendNodeId: 456 } };
+    if (
+      method === "Input.dispatchMouseEvent" &&
+      (params as { type?: string }).type === "mousePressed" &&
+      options.chooser
+    ) {
+      cdpEvent?.({ tabId: 4 }, "Page.fileChooserOpened", options.chooser);
+    }
+    return {};
+  });
+  const cdp: CdpRunner = {
+    send: send as unknown as CdpRunner["send"],
+    onEvent: (handler) => {
+      cdpEvent = handler;
+      return { dispose: vi.fn() };
+    },
+  };
+  return {
+    calls,
+    emitChooser: (event: { frameId?: string; backendNodeId?: number; mode?: string }) =>
+      cdpEvent?.({ tabId: 4 }, "Page.fileChooserOpened", event),
+    cdp,
+  };
+}
+
+function dropCdp(
+  options: {
+    targetContainsPoint?: boolean;
+    dispatchError?: (type: string) => Error | Promise<never> | undefined;
+    onCall?: (method: string) => void;
+  } = {},
+) {
+  const calls: Array<{ method: string; params?: object }> = [];
+  const detach = vi.fn(async () => {});
+  const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
+    calls.push({ method, params });
+    options.onCall?.(method);
+    if (method === "DOM.scrollIntoViewIfNeeded") return {};
+    if (method === "Page.getLayoutMetrics") {
+      return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+    }
+    if (method === "DOM.getContentQuads") {
+      return { quads: [[10, 20, 210, 20, 210, 120, 10, 120]] };
+    }
+    if (method === "DOM.getNodeForLocation") return { backendNodeId: 124 };
+    if (method === "DOM.resolveNode") {
+      const id = (params as { backendNodeId?: number }).backendNodeId;
+      return { object: { objectId: id === 123 ? "drop-target" : "hit-target" } };
+    }
+    if (method === "Runtime.callFunctionOn") {
+      return { result: { value: options.targetContainsPoint ?? true } };
+    }
+    if (method === "Input.dispatchDragEvent") {
+      const type = (params as { type?: string }).type ?? "";
+      const error = options.dispatchError?.(type);
+      if (error instanceof Promise) return error;
+      if (error) throw error;
+      return {};
+    }
+    if (method === "Runtime.releaseObjectGroup") return {};
+    throw new Error(`unexpected drop CDP command ${method}`);
+  });
+  const cdp: CdpRunner = {
+    send: send as unknown as CdpRunner["send"],
+    detach,
+  };
+  return { calls, cdp, detach };
+}
+
+describe("file transfer tools", () => {
+  it("captures the file input activated by the requested click and injects only staged paths", async () => {
+    const manager = sessions();
+    const ctx = await manager.start("s1");
+    ctx.refStore.set("e3", 123, { tabId: 4 });
+    const { cdp, calls } = uploadCdp();
+
+    const result = await handleUpload(
+      manager,
+      {
+        session_id: "s1",
+        ref: "@e3",
+        files: [
+          { transfer_id: "tr_1", name: "one.png", staged_path: "/private/stage/one" },
+          { transfer_id: "tr_2", name: "two.png", staged_path: "/private/stage/two" },
+        ],
+      },
+      { cdp, tabsApi: tabsApi() },
+    );
+
+    expect(result).toMatchObject({ tab_id: 4, file_names: ["one.png", "two.png"] });
+    expect(calls[0]).toEqual({
+      method: "Page.setInterceptFileChooserDialog",
+      params: { enabled: true },
+    });
+    expect(calls).toContainEqual({
+      method: "Page.setInterceptFileChooserDialog",
+      params: { enabled: false, cancel: true },
+    });
+    expect(calls).toContainEqual({
+      method: "DOM.setFileInputFiles",
+      params: { files: ["/private/stage/one", "/private/stage/two"], backendNodeId: 456 },
+    });
+  });
+
+  it("fails immediately when the trigger does not activate a file input", async () => {
+    const { cdp } = uploadCdp({ inputCount: 0 });
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger: async () => ({ tab_id: 4, x: 10, y: 10 }),
+    });
+
+    expect(result).toMatchObject({
+      code: "unsupported",
+      data: { reason: "file_input_not_activated", phase: "resolve_input" },
+    });
+  });
+
+  it("fails before clicking when chooser interception is unavailable", async () => {
+    const trigger = vi.fn(async () => ({ tab_id: 4, x: 10, y: 10 }));
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId: number, method: string) => {
+        if (method === "Page.setInterceptFileChooserDialog") {
+          throw new Error("method unavailable");
+        }
+        return {};
+      }) as CdpRunner["send"],
+    };
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger,
+    });
+
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { effect_state: "none", phase: "arm_interception" },
+    });
+    expect(trigger).not.toHaveBeenCalled();
+  });
+
+  it("uses an exact chooser event as an independent input-location signal", async () => {
+    const { cdp, calls, emitChooser } = uploadCdp({ inputCount: 0 });
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget("f1"),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger: async () => {
+        emitChooser({ frameId: "f1", backendNodeId: 789, mode: "selectSingle" });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({ multiple: false });
+    expect(calls).toContainEqual({
+      method: "DOM.setFileInputFiles",
+      params: { files: ["/private/stage/one"], backendNodeId: 789 },
+    });
+  });
+
+  it("reports a File System Access picker without waiting for a timeout", async () => {
+    const { cdp, emitChooser } = uploadCdp({
+      inputCount: 0,
+    });
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget("f1"),
+      files: ["/private/stage/one"],
+      timeoutMs: 100,
+      trigger: async () => {
+        emitChooser({ frameId: "f1", mode: "selectSingle" });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({
+      code: "unsupported",
+      message: "upload trigger invoked a non-input file picker",
+      data: { reason: "file_input_not_activated", phase: "resolve_input" },
+    });
+  });
+
+  it("bounds a stuck file-input probe", async () => {
+    const { cdp } = uploadCdp({ pendingResolve: true });
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 5,
+      trigger: vi.fn(),
+    });
+
+    expect(result).toMatchObject({
+      code: "timeout",
+      data: { reason: "file_input_probe_failed", phase: "arm_input_probe" },
+    });
+  });
+
+  it("marks a timed-out file assignment unknown and detaches browser state", async () => {
+    const fixture = uploadCdp();
+    const originalSend = fixture.cdp.send;
+    const detach = vi.fn(async () => {});
+    fixture.cdp.detach = detach;
+    fixture.cdp.send = vi.fn((tabId: number, method: string, params?: object) => {
+      if (method === "DOM.setFileInputFiles") return new Promise<never>(() => {});
+      return originalSend(tabId, method, params);
+    }) as CdpRunner["send"];
+
+    const result = await uploadThroughActivatedFileInput({
+      cdp: fixture.cdp,
+      actionTarget: actionTarget(),
+      files: ["/private/stage/one"],
+      timeoutMs: 10,
+      trigger: async () => ({ tab_id: 4, x: 10, y: 10 }),
+    });
+
+    expect(result).toMatchObject({
+      code: "timeout",
+      data: { effect_state: "unknown", phase: "set_files" },
+    });
+    expect(detach).toHaveBeenCalledWith(4);
+  });
+
+  it("delivers staged files through one explicit native drop without clicking", async () => {
+    const manager = sessions();
+    const ctx = await manager.start("s1");
+    ctx.refStore.set("e3", 123, { tabId: 4 });
+    const lifecycle: string[] = [];
+    const { cdp, calls } = dropCdp({ onCall: (method) => lifecycle.push(method) });
+    const overlayPhases: string[] = [];
+
+    const result = await handleUpload(
+      manager,
+      {
+        session_id: "s1",
+        ref: "@e3",
+        mode: "drop",
+        files: [{ transfer_id: "tr_1", name: "one.png", staged_path: "/stage/one.png" }],
+      },
+      {
+        cdp,
+        tabsApi: tabsApi(),
+        sendToTab: vi.fn(async (_tabId, message) => {
+          overlayPhases.push(message.phase);
+          lifecycle.push(`overlay:${message.phase}`);
+        }),
+      },
+    );
+
+    expect(result).toMatchObject({ tab_id: 4, used_ref: "e3", file_names: ["one.png"] });
+    expect(calls.filter((call) => call.method === "Input.dispatchDragEvent")).toEqual([
+      {
+        method: "Input.dispatchDragEvent",
+        params: {
+          type: "dragEnter",
+          x: 110,
+          y: 70,
+          data: { items: [], files: ["/stage/one.png"], dragOperationsMask: 1 },
+        },
+      },
+      {
+        method: "Input.dispatchDragEvent",
+        params: {
+          type: "dragOver",
+          x: 110,
+          y: 70,
+          data: { items: [], files: ["/stage/one.png"], dragOperationsMask: 1 },
+        },
+      },
+      {
+        method: "Input.dispatchDragEvent",
+        params: {
+          type: "drop",
+          x: 110,
+          y: 70,
+          data: { items: [], files: ["/stage/one.png"], dragOperationsMask: 1 },
+        },
+      },
+    ]);
+    expect(calls.some((call) => call.method === "Input.dispatchMouseEvent")).toBe(false);
+    expect(overlayPhases).toEqual(["begin", "end"]);
+    expect(lifecycle.indexOf("DOM.getContentQuads")).toBeLessThan(
+      lifecycle.indexOf("overlay:begin"),
+    );
+    expect(lifecycle.indexOf("overlay:begin")).toBeLessThan(
+      lifecycle.indexOf("DOM.getNodeForLocation"),
+    );
+    expect(lifecycle.lastIndexOf("Input.dispatchDragEvent")).toBeLessThan(
+      lifecycle.indexOf("overlay:end"),
+    );
+    expect(lifecycle.indexOf("overlay:end")).toBeLessThan(
+      lifecycle.indexOf("Runtime.releaseObjectGroup"),
+    );
+  });
+
+  it("fails closed before dragging when another element owns the action point", async () => {
+    const { cdp, calls } = dropCdp({ targetContainsPoint: false });
+    const result = await uploadThroughFileDrop({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/stage/one.png"],
+      timeoutMs: 100,
+      withOverlayHidden: withoutOverlay,
+    });
+
+    expect(result).toMatchObject({
+      code: "permission_denied",
+      data: {
+        reason: "file_drop_target_unavailable",
+        mechanism: "drop",
+        effect_state: "none",
+        phase: "resolve_target",
+      },
+    });
+    expect(calls.some((call) => call.method === "Input.dispatchDragEvent")).toBe(false);
+  });
+
+  it("dispatches an OOPIF file drop in the child target's local coordinates", async () => {
+    const rootCalls: Array<{ method: string; params?: object }> = [];
+    const childCalls: Array<{ method: string; params?: object }> = [];
+    const cdp: CdpRunner = {
+      send: vi.fn(async (_tabId, method, params) => {
+        rootCalls.push({ method, params });
+        if (method === "DOM.scrollIntoViewIfNeeded") return {};
+        if (method === "DOM.getBoxModel") {
+          return { model: { content: [100, 100, 300, 100, 300, 200, 100, 200] } };
+        }
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 800, clientHeight: 600 } };
+        }
+        throw new Error(`unexpected root command ${method}`);
+      }) as CdpRunner["send"],
+      sendToTarget: vi.fn(async (_target, method, params) => {
+        childCalls.push({ method, params });
+        if (method === "DOM.scrollIntoViewIfNeeded") return {};
+        if (method === "DOM.getContentQuads") {
+          return { quads: [[10, 20, 210, 20, 210, 120, 10, 120]] };
+        }
+        if (method === "Page.getLayoutMetrics") {
+          return { cssLayoutViewport: { clientWidth: 400, clientHeight: 300 } };
+        }
+        if (method === "DOM.getNodeForLocation") {
+          return { backendNodeId: 124, frameId: "child" };
+        }
+        if (method === "DOM.resolveNode") {
+          const id = (params as { backendNodeId?: number }).backendNodeId;
+          return { object: { objectId: id === 123 ? "drop-target" : "hit-target" } };
+        }
+        if (method === "Runtime.callFunctionOn") return { result: { value: true } };
+        if (method === "Input.dispatchDragEvent" || method === "Runtime.releaseObjectGroup") {
+          return {};
+        }
+        throw new Error(`unexpected child command ${method}`);
+      }) as CdpRunner["sendToTarget"],
+      getFrameGraph: vi.fn(async () => ({
+        rootFrameId: "main",
+        frames: [
+          { frameId: "main", target: { tabId: 4 } },
+          {
+            frameId: "child",
+            parentFrameId: "main",
+            ownerBackendNodeId: 10,
+            target: { tabId: 4, sessionId: "child-session" },
+          },
+        ],
+      })),
+    };
+
+    const result = await uploadThroughFileDrop({
+      cdp,
+      actionTarget: actionTarget("child", "child-session"),
+      files: ["/stage/one.png"],
+      timeoutMs: 100,
+      withOverlayHidden: withoutOverlay,
+    });
+
+    expect(result).toMatchObject({ x: 110, y: 70 });
+    expect(
+      childCalls
+        .filter((call) => call.method === "Input.dispatchDragEvent")
+        .map((call) => call.params),
+    ).toEqual([
+      expect.objectContaining({ type: "dragEnter", x: 110, y: 70 }),
+      expect.objectContaining({ type: "dragOver", x: 110, y: 70 }),
+      expect.objectContaining({ type: "drop", x: 110, y: 70 }),
+    ]);
+    expect(rootCalls.some((call) => call.method === "Input.dispatchDragEvent")).toBe(false);
+  });
+
+  it("reports a missing native drag command as unsupported before commit", async () => {
+    const { cdp } = dropCdp({
+      dispatchError: (type) =>
+        type === "dragEnter" ? new Error("'Input.dispatchDragEvent' wasn't found") : undefined,
+    });
+    const result = await uploadThroughFileDrop({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/stage/one.png"],
+      timeoutMs: 100,
+      withOverlayHidden: withoutOverlay,
+    });
+
+    expect(result).toMatchObject({
+      code: "unsupported",
+      data: {
+        reason: "upload_mechanism_unsupported",
+        effect_state: "none",
+        phase: "drag_enter",
+      },
+    });
+  });
+
+  it("cancels an unresolved drag before returning a pre-commit timeout", async () => {
+    const { cdp, calls } = dropCdp({
+      dispatchError: (type) => (type === "dragEnter" ? new Promise<never>(() => {}) : undefined),
+    });
+    const result = await uploadThroughFileDrop({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/stage/one.png"],
+      timeoutMs: 10,
+      withOverlayHidden: withoutOverlay,
+    });
+
+    expect(result).toMatchObject({
+      code: "timeout",
+      data: { reason: "file_drop_failed", effect_state: "none", phase: "drag_enter" },
+    });
+    expect(calls).toContainEqual({
+      method: "Input.dispatchDragEvent",
+      params: expect.objectContaining({ type: "dragCancel" }),
+    });
+  });
+
+  it("marks an unresolved drop unknown and detaches browser state", async () => {
+    const { cdp, detach } = dropCdp({
+      dispatchError: (type) => (type === "drop" ? new Promise<never>(() => {}) : undefined),
+    });
+    const result = await uploadThroughFileDrop({
+      cdp,
+      actionTarget: actionTarget(),
+      files: ["/stage/one.png"],
+      timeoutMs: 10,
+      withOverlayHidden: withoutOverlay,
+    });
+
+    expect(result).toMatchObject({
+      code: "timeout",
+      data: { reason: "file_drop_failed", effect_state: "unknown", phase: "drop" },
+    });
+    expect(detach).toHaveBeenCalledWith(4);
+  });
+
+  it("routes one exact-target download through a browser-relative capability", async () => {
+    const manager = sessions();
+    const ctx = await manager.start("s1");
+    ctx.refStore.set("e3", 123, { tabId: 4 });
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 9,
+      url: "https://example.test/result.zip",
+      finalUrl: "https://example.test/result.zip",
+      filename: "result.zip",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: 12,
+      mime: "application/zip",
+      danger: "safe",
+    } as chrome.downloads.DownloadItem;
+    const completed = {
+      ...initial,
+      filename: "/profile/Downloads/BrowserSkill/tr_1/result.zip",
+      state: "complete",
+      fileSize: 12,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => [completed]),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    let suggested: chrome.downloads.DownloadFilenameSuggestion | undefined;
+    const send = vi.fn(async (_tabId: number, method: string, params?: object) => {
+      if (method === "Page.getLayoutMetrics")
+        return { cssLayoutViewport: { clientWidth: 1280, clientHeight: 720 } };
+      if (method === "DOM.getContentQuads") return { quads: [[0, 0, 20, 0, 20, 20, 0, 20]] };
+      if (
+        method === "Input.dispatchMouseEvent" &&
+        (params as { type?: string }).type === "mousePressed"
+      ) {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: "result.zip",
+        });
+        await new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, (value) => {
+            suggested = value;
+            resolve();
+          });
+        });
+        onCreated.emit(completed);
+      }
+      return {};
+    });
+    const cdp: CdpRunner = {
+      send: send as unknown as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+
+    const result = await handleDownload(
+      manager,
+      { session_id: "s1", ref: "@e3", browser_relative_dir: "BrowserSkill/tr_1" },
+      { cdp, tabsApi: tabsApi(), downloads },
+    );
+
+    expect(suggested).toEqual({
+      filename: "BrowserSkill/tr_1/result.zip",
+      conflictAction: "overwrite",
+    });
+    expect(result).toMatchObject({
+      tab_id: 4,
+      suggested_filename: "result.zip",
+      byte_size: 12,
+      browser_path: completed.filename,
+    });
+  });
+
+  it("does not claim a download without an intent from the exact target", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => []),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as unknown as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+    const unrelated = {
+      id: 17,
+      url: "https://example.test/unrelated.zip",
+      finalUrl: "https://example.test/unrelated.zip",
+      filename: "unrelated.zip",
+      state: "in_progress",
+    } as chrome.downloads.DownloadItem;
+    let defaultSuggestionCalled = false;
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4, sessionId: "expected-child" },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_1",
+      timeoutMs: 5,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4, sessionId: "other-child" }, "Page.downloadWillBegin", {
+          url: unrelated.url,
+          suggestedFilename: unrelated.filename,
+        });
+        onDeterminingFilename.emit(unrelated, (suggestion) => {
+          defaultSuggestionCalled = suggestion === undefined;
+        });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(defaultSuggestionCalled).toBe(true);
+    expect(downloads.cancel).not.toHaveBeenCalled();
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { reason: "download_capture_failed" },
+    });
+  });
+
+  it("correlates a filename candidate that arrives before the CDP intent", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 21,
+      url: "https://example.test/candidate-first.bin",
+      finalUrl: "https://example.test/candidate-first.bin",
+      filename: "candidate-first.bin",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: 4,
+      bytesReceived: 0,
+    } as chrome.downloads.DownloadItem;
+    const complete = {
+      ...initial,
+      state: "complete",
+      fileSize: 4,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => [complete]),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+    let suggestion: chrome.downloads.DownloadFilenameSuggestion | undefined;
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_21",
+      timeoutMs: 1_000,
+      trigger: async () => {
+        const suggested = new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, (value) => {
+            suggestion = value;
+            resolve();
+          });
+        });
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: initial.filename,
+        });
+        await suggested;
+        onCreated.emit(complete);
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(suggestion).toEqual({
+      filename: "BrowserSkill/tr_21/candidate-first.bin",
+      conflictAction: "overwrite",
+    });
+    expect(result).toMatchObject({ item: { id: 21, state: "complete" } });
+  });
+
+  it("removes a completed download when the final size exceeds the limit", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 22,
+      url: "https://example.test/oversized.bin",
+      finalUrl: "https://example.test/oversized.bin",
+      filename: "oversized.bin",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: -1,
+      bytesReceived: 0,
+    } as chrome.downloads.DownloadItem;
+    const complete = {
+      ...initial,
+      filename: "/profile/Downloads/BrowserSkill/tr_22/oversized.bin",
+      state: "complete",
+      fileSize: 8,
+      totalBytes: 8,
+      bytesReceived: 8,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => [complete]),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_22",
+      maxByteSize: 4,
+      timeoutMs: 1_000,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: initial.filename,
+        });
+        await new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, () => resolve());
+        });
+        onCreated.emit(initial);
+        onChanged.emit({ id: initial.id, state: { current: "complete" } });
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { reason: "download_capture_failed", effect_state: "committed" },
+    });
+    expect(downloads.removeFile).toHaveBeenCalledWith(initial.id);
+    expect(downloads.cancel).not.toHaveBeenCalled();
+  });
+
+  it("reconciles a download that completes while cancellation is being requested", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const initial = {
+      id: 23,
+      url: "https://example.test/racing.bin",
+      finalUrl: "https://example.test/racing.bin",
+      filename: "racing.bin",
+      state: "in_progress",
+      fileSize: -1,
+      totalBytes: -1,
+      bytesReceived: 0,
+    } as chrome.downloads.DownloadItem;
+    const complete = {
+      ...initial,
+      filename: "/profile/Downloads/BrowserSkill/tr_23/racing.bin",
+      state: "complete",
+      fileSize: 4,
+      totalBytes: 4,
+      bytesReceived: 4,
+    } as chrome.downloads.DownloadItem;
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn().mockResolvedValueOnce([initial]).mockResolvedValueOnce([complete]),
+      cancel: vi.fn(async () => {
+        throw new Error("download already complete");
+      }),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_23",
+      timeoutMs: 80,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: initial.url,
+          suggestedFilename: initial.filename,
+        });
+        await new Promise<void>((resolve) => {
+          onDeterminingFilename.emit(initial, () => resolve());
+        });
+        onCreated.emit(initial);
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { reason: "download_capture_failed", effect_state: "committed" },
+    });
+    expect(downloads.cancel).toHaveBeenCalledWith(initial.id);
+    expect(downloads.removeFile).toHaveBeenCalledWith(initial.id);
+    expect(result).not.toMatchObject({ data: { cleanup_state: "failed" } });
+  });
+
+  it("rejects ambiguous attribution without cancelling either unclaimed download", async () => {
+    const onCreated = fakeEvent<(item: chrome.downloads.DownloadItem) => void>();
+    const onChanged = fakeEvent<(delta: chrome.downloads.DownloadDelta) => void>();
+    const onDeterminingFilename =
+      fakeEvent<
+        (
+          item: chrome.downloads.DownloadItem,
+          suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+        ) => void | true
+      >();
+    const downloads: DownloadsApi = {
+      onCreated,
+      onChanged,
+      onDeterminingFilename,
+      search: vi.fn(async () => []),
+      cancel: vi.fn(async () => {}),
+      removeFile: vi.fn(async () => {}),
+    };
+    let cdpEvent: Parameters<NonNullable<CdpRunner["onEvent"]>>[0] | undefined;
+    const cdp: CdpRunner = {
+      send: vi.fn(async () => ({})) as CdpRunner["send"],
+      onEvent: (handler) => {
+        cdpEvent = handler;
+        return { dispose: vi.fn() };
+      },
+    };
+    const defaults: number[] = [];
+    const candidate = (id: number) =>
+      ({
+        id,
+        url: "https://example.test/same.bin",
+        finalUrl: "https://example.test/same.bin",
+        filename: "same.bin",
+        state: "in_progress",
+      }) as chrome.downloads.DownloadItem;
+
+    const result = await captureBrowserDownload({
+      cdp,
+      target: { tabId: 4 },
+      downloads,
+      browserRelativeDir: "BrowserSkill/tr_ambiguous",
+      timeoutMs: 100,
+      trigger: async () => {
+        cdpEvent?.({ tabId: 4 }, "Page.downloadWillBegin", {
+          url: "https://example.test/same.bin",
+          suggestedFilename: "same.bin",
+        });
+        for (const id of [31, 32]) {
+          onDeterminingFilename.emit(candidate(id), (value) => {
+            if (value === undefined) defaults.push(id);
+          });
+        }
+        return { tab_id: 4, x: 10, y: 10 };
+      },
+    });
+
+    expect(defaults.sort()).toEqual([31, 32]);
+    expect(downloads.cancel).not.toHaveBeenCalled();
+    expect(result).toMatchObject({
+      code: "cdp_failed",
+      data: { effect_state: "unknown", phase: "attribution" },
+    });
+  });
+});
@@ -169,6 +169,7 @@ describe("frame geometry projection", () => {
    expect(geometry).toMatchObject({
      topBounds: { x: 100, y: 100, width: 200, height: 100 },
      actionPoint: { x: 200, y: 150 },
+      targetActionPoint: { x: 100, y: 50 },
    });
  });

@@ -261,6 +262,7 @@ describe("frame geometry projection", () => {
    expect(geometry).toMatchObject({
      topBounds: { x: 100, y: 100, width: 200, height: 100 },
      actionPoint: { x: 200, y: 150 },
+      targetActionPoint: { x: 200, y: 150 },
    });
  });

@@ -66,6 +66,52 @@ function makeApis(
 }

 describe("handleSessionStop with auto-return", () => {
+  it("leaves the session untouched when cancellation arrived before teardown", async () => {
+    const aw = fakeAgentWindow([100]);
+    const sm = new SessionManager({ agentWindow: aw });
+    await sm.start("aa11");
+    const cdp = { detachSession: vi.fn(async () => {}) };
+    const controller = new AbortController();
+    controller.abort();
+
+    const res = await handleSessionStop(
+      sm,
+      { session_id: "aa11" },
+      { cdp, signal: controller.signal },
+    );
+
+    expect(res).toMatchObject({ code: "cancelled" });
+    expect(sm.has("aa11")).toBe(true);
+    expect(cdp.detachSession).not.toHaveBeenCalled();
+    expect(aw.remove).not.toHaveBeenCalled();
+  });
+
+  it("does not close the Agent Window when cancellation lands during CDP detach", async () => {
+    const aw = fakeAgentWindow([100]);
+    const sm = new SessionManager({ agentWindow: aw });
+    await sm.start("aa11");
+    const controller = new AbortController();
+    let finishDetach: () => void = () => {};
+    const detach = new Promise<void>((resolve) => {
+      finishDetach = resolve;
+    });
+    const cdp = { detachSession: vi.fn(() => detach) };
+
+    const stopping = handleSessionStop(
+      sm,
+      { session_id: "aa11" },
+      { cdp, signal: controller.signal },
+    );
+    await vi.waitFor(() => expect(cdp.detachSession).toHaveBeenCalledWith("aa11"));
+    controller.abort();
+    finishDetach();
+
+    const res = await stopping;
+    expect(res).toMatchObject({ code: "cancelled" });
+    expect(sm.has("aa11")).toBe(true);
+    expect(aw.remove).not.toHaveBeenCalled();
+  });
+
  it("returns every borrowed tab and closes the Agent Window in the right order", async () => {
    const aw = fakeAgentWindow([100]);
    const sm = new SessionManager({ agentWindow: aw });
@@ -24,7 +24,7 @@ export interface BorrowResponseMessage {
  allowed: boolean;
 }

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

+    // Bring the user window to the front so the overlay is visible even
+    // when the Agent Window has stolen focus. This is fire-and-forget: if
+    // it fails the overlay / OS notification still give the user a path.
+    void windowsApi.update(notificationAnchor.windowId, { focused: true }).catch((err) => {
+      console.debug("[bsk borrow] proactive focus of user window failed", err);
+    });
+
    // Surface the OS notification *before* messaging any candidate so the
    // user has a parallel signal even if every content script is missing.
    // The Allow / Deny buttons let the user authorize explicitly when the
@@ -0,0 +1,9 @@
+export {
+  type CaptureVomObservationOptions,
+  captureVomObservation,
+} from "./observation";
+export {
+  type CaptureVomFrame,
+  type CaptureVomMatchNode,
+  type CaptureVomObservationResult,
+} from "./vom/record-safe-observation";
@@ -4,6 +4,7 @@ import type { Transport } from "@/transport/transport";
 import type {
  ClickParams,
  ConsoleParams,
+  DownloadParams,
  EmulateParams,
  EvaluateParams,
  FillParams,
@@ -28,10 +29,12 @@ import type {
  ScreenshotParams,
  SelectParams,
  SnapshotParams,
+  UploadParams,
  WaitForNavigationParams,
 } from "@/transport/types";
 import { isRequestFrame } from "@/transport/types";
 import { handleConsole } from "./console";
+import { handleDownload } from "./download";
 import { type EmulateCdpRunner, handleEmulate } from "./emulate";
 import { handleEvaluate } from "./evaluate";
 import { handleRequestHelp } from "./human-loop";
@@ -51,7 +54,12 @@ import {
  handleScreenshot,
  handleSnapshot,
 } from "./observation";
-import { handleRecordAwait, handleRecordStart, handleRecordStop } from "./record";
+import {
+  handleRecordAwait,
+  handleRecordStart,
+  handleRecordStop,
+  type RecordRuntimeDeps,
+} from "./record";
 import {
  handleSessionStart,
  handleSessionStop,
@@ -74,6 +82,7 @@ import {
  type TabReturnParams,
  type TabSelectParams,
 } from "./tabs";
+import { handleUpload } from "./upload";
 import { handleWaitForNavigation } from "./waits";
 import { handleWindowResize, type WindowResizeParams } from "./window";

@@ -99,6 +108,7 @@ export interface DispatcherDeps {
  transport: Transport;
  sessions: SessionManager;
  cdp?: DispatcherCdpRunner;
+  recording?: RecordRuntimeDeps;
  /**
   * Invoked whenever a dispatched RPC may have changed the live
   * session set (currently `tool.session_start` and
@@ -134,6 +144,7 @@ export class ToolDispatcher {
  private readonly transport: Transport;
  private readonly sessions: SessionManager;
  private readonly cdp?: DispatcherCdpRunner;
+  private readonly recording?: RecordRuntimeDeps;
  private readonly onSessionsChanged?: () => void;
  private readonly onBrowserControlResumed?: (sessionId: string) => void;
  private readonly approveBorrow?: BorrowConfirmationApprover;
@@ -153,6 +164,7 @@ export class ToolDispatcher {
    this.transport = deps.transport;
    this.sessions = deps.sessions;
    this.cdp = deps.cdp;
+    this.recording = deps.recording;
    this.onSessionsChanged = deps.onSessionsChanged;
    this.onBrowserControlResumed = deps.onBrowserControlResumed;
    this.approveBorrow = deps.approveBorrow;
@@ -290,6 +302,7 @@ export class ToolDispatcher {
        await this.releaseHoverLatch((req.params as SessionStopParams).session_id);
        return handleSessionStop(this.sessions, req.params as SessionStopParams, {
          cdp: this.cdp,
+          signal,
        });
      }
      case "tool.tab_list":
@@ -374,7 +387,11 @@ export class ToolDispatcher {
                ? {
                    cdp: this.cdp,
                    tabsApi: chromeTabsCaptureApi,
-                    conditionalSurfaceProbe: !this.hasHoverLatchForScope(hoverScope),
+                    // Active hover probing is opt-in. A held hover latch still
+                    // suppresses it, because probing would move the cursor off
+                    // the element the caller is deliberately holding.
+                    conditionalSurfaceProbe:
+                      params.probe_hover === true && !this.hasHoverLatchForScope(hoverScope),
                    hoverProbeBypassOverlay: bypassOverlay,
                  }
                : undefined,
@@ -504,6 +521,40 @@ export class ToolDispatcher {
            ),
          signal,
        );
+      case "tool.upload":
+        return this.withHoverReleaseForRequest(
+          req.params as UploadParams,
+          () =>
+            this.cdp
+              ? handleUpload(this.sessions, req.params as UploadParams, {
+                  cdp: this.cdp,
+                  tabsApi: chromeTabsApi,
+                  signal,
+                  bypassOverlay,
+                })
+              : Promise.resolve({
+                  code: "unsupported",
+                  message: "upload requires CDP",
+                } satisfies RpcError),
+          signal,
+        );
+      case "tool.download":
+        return this.withHoverReleaseForRequest(
+          req.params as DownloadParams,
+          () =>
+            this.cdp
+              ? handleDownload(this.sessions, req.params as DownloadParams, {
+                  cdp: this.cdp,
+                  tabsApi: chromeTabsApi,
+                  signal,
+                  bypassOverlay,
+                })
+              : Promise.resolve({
+                  code: "unsupported",
+                  message: "download requires CDP",
+                } satisfies RpcError),
+          signal,
+        );
      case "tool.evaluate":
        return handleEvaluate(
          this.sessions,
@@ -530,44 +581,26 @@ export class ToolDispatcher {
          signal,
        });
      case "tool.record_start":
-        return handleRecordStart(this.sessions, req.params as RecordStartParams, {
-          tabsApi: chromeTabsApi,
-          sendToTab: (tabId, msg) => chrome.tabs.sendMessage(tabId, msg),
-          bypassOverlay: async (tabId, enabled) => {
-            try {
-              await chrome.tabs.sendMessage(tabId, {
-                type: OVERLAY_AUTOMATION_BYPASS,
-                enabled,
-              });
-            } catch {
-              // Content script may be unavailable on restricted pages.
-            }
-          },
-          ...(this.cdp ? { cdp: this.cdp } : {}),
-          signal,
-        });
+        return this.recording
+          ? handleRecordStart(this.sessions, req.params as RecordStartParams, {
+              ...this.recording,
+              signal,
+            })
+          : recordingRuntimeUnavailable();
      case "tool.record_stop":
-        return handleRecordStop(this.sessions, req.params as RecordStopParams, {
-          tabsApi: chromeTabsApi,
-          sendToTab: (tabId, msg) => chrome.tabs.sendMessage(tabId, msg),
-          bypassOverlay: async (tabId, enabled) => {
-            try {
-              await chrome.tabs.sendMessage(tabId, {
-                type: OVERLAY_AUTOMATION_BYPASS,
-                enabled,
-              });
-            } catch {
-              // Content script may be unavailable on restricted pages.
-            }
-          },
-          signal,
-        });
+        return this.recording
+          ? handleRecordStop(this.sessions, req.params as RecordStopParams, {
+              ...this.recording,
+              signal,
+            })
+          : recordingRuntimeUnavailable();
      case "tool.record_await":
-        return handleRecordAwait(this.sessions, req.params as RecordAwaitParams, {
-          tabsApi: chromeTabsApi,
-          sendToTab: (tabId, msg) => chrome.tabs.sendMessage(tabId, msg),
-          signal,
-        });
+        return this.recording
+          ? handleRecordAwait(this.sessions, req.params as RecordAwaitParams, {
+              ...this.recording,
+              signal,
+            })
+          : recordingRuntimeUnavailable();
      default:
        return {
          code: "unknown_method",
@@ -703,6 +736,13 @@ function isRpcError(v: unknown): v is RpcError {
  );
 }

+function recordingRuntimeUnavailable(): RpcError {
+  return {
+    code: "protocol_error",
+    message: "recording runtime is unavailable",
+  };
+}
+
 function sessionIdForBrowserControlMethod(req: RequestFrame): string | null {
  switch (req.method) {
    case "tool.tab_create":
@@ -721,6 +761,8 @@ function sessionIdForBrowserControlMethod(req: RequestFrame): string | null {
    case "tool.fill":
    case "tool.press":
    case "tool.select":
+    case "tool.upload":
+    case "tool.download":
    case "tool.evaluate":
    case "tool.observe":
    case "tool.request_help":
@@ -0,0 +1,364 @@
+// Order-independent coordinator for one browser download. CDP supplies the
+// exact target/frame intent while chrome.downloads supplies the download id
+// and filename routing hook; neither event is assumed to arrive first.
+
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import type { ClickResult, RpcError, TransferEffectState } from "@/transport/types";
+import { transferError } from "./errors";
+import { type CdpRunner, isRpcError } from "./shared";
+
+const CORRELATION_GRACE_MS = 750;
+const UNIQUE_SETTLE_MS = 50;
+const SIZE_POLL_MS = 250;
+
+type DeterminingFilenameListener = (
+  item: chrome.downloads.DownloadItem,
+  suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void,
+) => void | true;
+
+interface ListenerEvent<T> {
+  addListener(listener: T): void;
+  removeListener(listener: T): void;
+}
+
+export interface DownloadsApi {
+  onCreated: ListenerEvent<(item: chrome.downloads.DownloadItem) => void>;
+  onChanged: ListenerEvent<(delta: chrome.downloads.DownloadDelta) => void>;
+  onDeterminingFilename: ListenerEvent<DeterminingFilenameListener>;
+  search(query: chrome.downloads.DownloadQuery): Promise<chrome.downloads.DownloadItem[]>;
+  cancel(downloadId: number): Promise<void>;
+  removeFile(downloadId: number): Promise<void>;
+}
+
+export const chromeDownloadsApi: DownloadsApi = {
+  get onCreated() {
+    return chrome.downloads.onCreated;
+  },
+  get onChanged() {
+    return chrome.downloads.onChanged;
+  },
+  get onDeterminingFilename() {
+    return chrome.downloads.onDeterminingFilename;
+  },
+  search: (query) => chrome.downloads.search(query),
+  cancel: (id) => chrome.downloads.cancel(id),
+  removeFile: (id) => chrome.downloads.removeFile(id),
+};
+
+export interface DownloadCaptureOptions {
+  cdp: CdpRunner;
+  target: CdpTarget;
+  expectedFrameId?: string;
+  downloads: DownloadsApi;
+  browserRelativeDir: string;
+  maxByteSize?: number;
+  timeoutMs: number;
+  signal?: AbortSignal;
+  trigger(): Promise<ClickResult | RpcError>;
+}
+
+export interface DownloadCaptureResult {
+  click: ClickResult;
+  item: chrome.downloads.DownloadItem;
+}
+
+interface DownloadIntent {
+  url: string;
+  suggestedFilename: string;
+  frameId?: string;
+}
+
+interface DownloadCandidate {
+  item: chrome.downloads.DownloadItem;
+  suggest: (suggestion?: chrome.downloads.DownloadFilenameSuggestion) => void;
+  suggested: boolean;
+  graceTimer: ReturnType<typeof setTimeout>;
+}
+
+function safeBasename(filename: string): string {
+  const basename = filename.split(/[\\/]/).pop()?.trim();
+  return basename && basename !== "." && basename !== ".." ? basename : "download";
+}
+
+function sameTarget(source: { tabId?: number; sessionId?: string }, target: CdpTarget): boolean {
+  return source.tabId === target.tabId && source.sessionId === target.sessionId;
+}
+
+function matchesIntent(item: chrome.downloads.DownloadItem, intent: DownloadIntent): boolean {
+  const urlMatches = item.url === intent.url || item.finalUrl === intent.url;
+  return urlMatches && safeBasename(item.filename) === safeBasename(intent.suggestedFilename);
+}
+
+function knownSize(item: chrome.downloads.DownloadItem): number | undefined {
+  if (item.fileSize >= 0) return item.fileSize;
+  if (item.totalBytes >= 0) return item.totalBytes;
+  return undefined;
+}
+
+function captureError(
+  message: string,
+  effectState: TransferEffectState,
+  phase: string,
+  cleanupFailed = false,
+): RpcError {
+  return transferError("cdp_failed", "download_capture_failed", message, {
+    effectState,
+    phase,
+    ...(cleanupFailed ? { cleanupState: "failed" } : {}),
+  });
+}
+
+async function cleanupClaimedDownload(downloads: DownloadsApi, downloadId: number): Promise<void> {
+  const lookup = async () => (await downloads.search({ id: downloadId }))[0];
+  const item = await lookup();
+  if (!item || item.state === "interrupted") return;
+  if (item.state === "complete") {
+    await downloads.removeFile(downloadId);
+    return;
+  }
+
+  try {
+    await downloads.cancel(downloadId);
+  } catch (cancelError) {
+    // Completion can win the race after the lookup but before cancellation.
+    // Reconcile against Chrome's authoritative state before declaring cleanup
+    // failed so every terminal state has one explicit cleanup path.
+    const reconciled = await lookup();
+    if (!reconciled || reconciled.state === "interrupted") return;
+    if (reconciled.state === "complete") {
+      await downloads.removeFile(downloadId);
+      return;
+    }
+    throw cancelError;
+  }
+}
+
+export async function captureBrowserDownload(
+  options: DownloadCaptureOptions,
+): Promise<DownloadCaptureResult | RpcError> {
+  let click: ClickResult | undefined;
+  let intent: DownloadIntent | undefined;
+  let capturedId: number | undefined;
+  let settled = false;
+  let succeeded = false;
+  let failureResult: RpcError | undefined;
+  let uniquenessTimer: ReturnType<typeof setTimeout> | undefined;
+  let operationTimer: ReturnType<typeof setTimeout> | undefined;
+  let sizePoll: ReturnType<typeof setInterval> | undefined;
+  const candidates = new Map<number, DownloadCandidate>();
+  const createdItems = new Map<number, chrome.downloads.DownloadItem>();
+
+  let resolveCompletion!: (item: chrome.downloads.DownloadItem) => void;
+  let rejectCompletion!: (error: Error) => void;
+  const completion = new Promise<chrome.downloads.DownloadItem>((resolve, reject) => {
+    resolveCompletion = resolve;
+    rejectCompletion = reject;
+  });
+  const fail = (error: Error) => {
+    if (settled) return;
+    settled = true;
+    rejectCompletion(error);
+  };
+  const complete = (item: chrome.downloads.DownloadItem) => {
+    if (settled) return;
+    const size = knownSize(item);
+    if (size !== undefined && options.maxByteSize !== undefined && size > options.maxByteSize) {
+      fail(new Error(`download exceeds transfer limit ${options.maxByteSize}`));
+      return;
+    }
+    settled = true;
+    resolveCompletion(item);
+  };
+  const suggestDefault = (candidate: DownloadCandidate) => {
+    if (candidate.suggested) return;
+    candidate.suggested = true;
+    candidate.suggest();
+  };
+  const matchingCandidates = (): DownloadCandidate[] => {
+    const currentIntent = intent;
+    return currentIntent
+      ? [...candidates.values()].filter(
+          (candidate) => !candidate.suggested && matchesIntent(candidate.item, currentIntent),
+        )
+      : [];
+  };
+
+  const claimUnique = () => {
+    uniquenessTimer = undefined;
+    if (settled || capturedId !== undefined || !intent) return;
+    const matches = matchingCandidates();
+    if (matches.length !== 1) {
+      if (matches.length > 1) {
+        for (const candidate of matches) suggestDefault(candidate);
+        fail(new Error("download attribution is ambiguous"));
+      }
+      return;
+    }
+    const candidate = matches[0];
+    candidate.suggested = true;
+    clearTimeout(candidate.graceTimer);
+    capturedId = candidate.item.id;
+    candidate.suggest({
+      filename: `${options.browserRelativeDir}/${safeBasename(intent.suggestedFilename)}`,
+      conflictAction: "overwrite",
+    });
+    const size = knownSize(candidate.item);
+    if (size !== undefined && options.maxByteSize !== undefined && size > options.maxByteSize) {
+      fail(new Error(`download exceeds transfer limit ${options.maxByteSize}`));
+      return;
+    }
+    const created = createdItems.get(candidate.item.id);
+    if (created?.state === "interrupted") {
+      fail(new Error(created.error ?? "download interrupted"));
+    } else if (created?.state === "complete") {
+      complete(created);
+    }
+  };
+  const reconcile = () => {
+    if (settled || capturedId !== undefined || !intent) return;
+    const matches = matchingCandidates();
+    if (matches.length > 1) {
+      for (const candidate of matches) suggestDefault(candidate);
+      fail(new Error("download attribution is ambiguous"));
+      return;
+    }
+    if (matches.length === 1 && !uniquenessTimer) {
+      uniquenessTimer = setTimeout(claimUnique, UNIQUE_SETTLE_MS);
+    }
+  };
+
+  const determiningListener: DeterminingFilenameListener = (item, suggest) => {
+    const candidate: DownloadCandidate = {
+      item,
+      suggest,
+      suggested: false,
+      graceTimer: setTimeout(() => {
+        suggestDefault(candidate);
+        candidates.delete(item.id);
+        if (intent && matchesIntent(item, intent) && capturedId === undefined) {
+          fail(new Error("download correlation grace elapsed before unique attribution"));
+        }
+      }, CORRELATION_GRACE_MS),
+    };
+    candidates.set(item.id, candidate);
+    reconcile();
+    return true;
+  };
+  const createdListener = (item: chrome.downloads.DownloadItem) => {
+    createdItems.set(item.id, item);
+    if (capturedId !== item.id) return;
+    if (item.state === "interrupted") {
+      fail(new Error(item.error ?? "download interrupted"));
+    } else if (item.state === "complete") {
+      complete(item);
+    }
+  };
+  const changedListener = async (delta: chrome.downloads.DownloadDelta) => {
+    if (capturedId === undefined || delta.id !== capturedId || settled) return;
+    if (delta.state?.current === "interrupted" || delta.error?.current) {
+      fail(new Error(delta.error?.current ?? "download interrupted"));
+      return;
+    }
+    if (delta.state?.current === "complete") {
+      try {
+        const [item] = await options.downloads.search({ id: delta.id });
+        if (item) complete(item);
+        else fail(new Error("completed download disappeared"));
+      } catch (err) {
+        fail(err instanceof Error ? err : new Error(String(err)));
+      }
+    }
+  };
+  const onAbort = () => fail(new DOMException("aborted", "AbortError"));
+  const cdpSubscription = options.cdp.onEvent?.((source, method, raw) => {
+    if (method !== "Page.downloadWillBegin" || !sameTarget(source, options.target)) return;
+    const event = raw as { url?: unknown; suggestedFilename?: unknown; frameId?: unknown };
+    if (typeof event.url !== "string" || typeof event.suggestedFilename !== "string") return;
+    if (options.expectedFrameId && event.frameId !== options.expectedFrameId) {
+      fail(new Error("download originated from a different frame"));
+      return;
+    }
+    if (intent) {
+      fail(new Error("download trigger produced more than one browser download intent"));
+      return;
+    }
+    intent = {
+      url: event.url,
+      suggestedFilename: event.suggestedFilename,
+      ...(typeof event.frameId === "string" ? { frameId: event.frameId } : {}),
+    };
+    reconcile();
+  });
+  if (!cdpSubscription) {
+    return captureError("CDP download intent subscription unavailable", "none", "arm");
+  }
+
+  options.downloads.onDeterminingFilename.addListener(determiningListener);
+  options.downloads.onCreated.addListener(createdListener);
+  options.downloads.onChanged.addListener(changedListener);
+  options.signal?.addEventListener("abort", onAbort, { once: true });
+  operationTimer = setTimeout(
+    () => fail(new Error("download did not complete before timeout")),
+    options.timeoutMs,
+  );
+  sizePoll = setInterval(() => {
+    if (capturedId === undefined || settled || options.maxByteSize === undefined) return;
+    void options.downloads
+      .search({ id: capturedId })
+      .then(([item]) => {
+        if (!item || settled) return;
+        if (item.bytesReceived > (options.maxByteSize as number)) {
+          fail(new Error(`download exceeds transfer limit ${options.maxByteSize}`));
+        }
+      })
+      .catch((err) => fail(err instanceof Error ? err : new Error(String(err))));
+  }, SIZE_POLL_MS);
+
+  try {
+    const triggered = await options.trigger();
+    if (isRpcError(triggered)) {
+      void completion.catch(() => undefined);
+      const effect: TransferEffectState =
+        capturedId !== undefined ? "committed" : intent ? "unknown" : "none";
+      failureResult = {
+        ...triggered,
+        data: { ...triggered.data, effect_state: effect, phase: "trigger" },
+      };
+      return failureResult;
+    }
+    click = triggered;
+    const item = await completion;
+    succeeded = true;
+    return { click, item };
+  } catch (err) {
+    const effect: TransferEffectState =
+      capturedId !== undefined ? "committed" : click ? "unknown" : "none";
+    failureResult = captureError(
+      err instanceof Error ? err.message : String(err),
+      effect,
+      capturedId !== undefined ? "download" : "attribution",
+    );
+    return failureResult;
+  } finally {
+    settled = true;
+    if (operationTimer) clearTimeout(operationTimer);
+    if (uniquenessTimer) clearTimeout(uniquenessTimer);
+    if (sizePoll) clearInterval(sizePoll);
+    options.signal?.removeEventListener("abort", onAbort);
+    options.downloads.onDeterminingFilename.removeListener(determiningListener);
+    options.downloads.onCreated.removeListener(createdListener);
+    options.downloads.onChanged.removeListener(changedListener);
+    cdpSubscription.dispose();
+    for (const candidate of candidates.values()) {
+      clearTimeout(candidate.graceTimer);
+      if (candidate.item.id !== capturedId) suggestDefault(candidate);
+    }
+    if (!succeeded && capturedId !== undefined) {
+      try {
+        await cleanupClaimedDownload(options.downloads, capturedId);
+      } catch {
+        if (failureResult?.data) failureResult.data.cleanup_state = "failed";
+      }
+    }
+  }
+}
@@ -0,0 +1,64 @@
+// Download orchestration: validate session/tab ownership, then delegate one
+// browser-global chrome.downloads transaction to download-capture.ts.
+
+import type { SessionManager } from "@/session-manager/manager";
+import type { DownloadParams, DownloadResult, RpcError } from "@/transport/types";
+import { captureBrowserDownload, chromeDownloadsApi, type DownloadsApi } from "./download-capture";
+import { clickResolvedTarget, type InteractionDeps, resolveActionTarget } from "./interaction";
+import { enforceAgentWindow, isRpcError, lookupSession, resolveTargetTab } from "./shared";
+
+let downloadActive = false;
+
+export type { DownloadsApi } from "./download-capture";
+
+export interface DownloadDeps extends InteractionDeps {
+  downloads?: DownloadsApi;
+}
+
+export async function handleDownload(
+  manager: SessionManager,
+  params: DownloadParams,
+  deps: DownloadDeps,
+): Promise<DownloadResult | RpcError> {
+  if (downloadActive) return { code: "invalid_params", message: "another bsk download is active" };
+  downloadActive = true;
+  try {
+    const ctx = lookupSession(manager, params, "download");
+    if (isRpcError(ctx)) return ctx;
+    const target = await resolveTargetTab(manager, ctx, params.tab_id, deps.tabsApi);
+    if (isRpcError(target)) return target;
+    const denied = enforceAgentWindow(ctx, target, "download");
+    if (denied) return denied;
+    if (!params.browser_relative_dir) {
+      return { code: "invalid_params", message: "download requires a daemon capability directory" };
+    }
+    const address = await resolveActionTarget(deps.cdp, ctx, target, params, "download");
+    if (isRpcError(address)) return address;
+
+    const capture = await captureBrowserDownload({
+      cdp: deps.cdp,
+      target: address.cdpTarget,
+      downloads: deps.downloads ?? chromeDownloadsApi,
+      browserRelativeDir: params.browser_relative_dir,
+      maxByteSize: params.max_byte_size,
+      timeoutMs: params.timeout_ms ?? 120_000,
+      signal: deps.signal,
+      expectedFrameId: address.frameId,
+      trigger: () => clickResolvedTarget(ctx, address, {}, deps),
+    });
+    if (isRpcError(capture)) return capture;
+    const { click, item } = capture;
+    return {
+      tab_id: target.tabId,
+      used_ref: click.used_ref,
+      used_selector: click.used_selector,
+      suggested_filename: item.filename.split(/[\\/]/).pop() ?? "download",
+      byte_size: item.fileSize >= 0 ? item.fileSize : item.totalBytes,
+      mime: item.mime || undefined,
+      danger: item.danger,
+      browser_path: item.filename,
+    };
+  } finally {
+    downloadActive = false;
+  }
+}
@@ -2,10 +2,23 @@
 // rendering. Extension handlers attach reasons here; human-facing copy
 // lives in bsk-cli `render_error.rs`.

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

 export type { RpcErrorData, RpcErrorReason };

+export interface TransferErrorOptions {
+  effectState: TransferEffectState;
+  phase: string;
+  cleanupState?: TransferCleanupState;
+}
+
 export function rpcError(
  code: ErrorCode,
  reason: RpcErrorReason,
@@ -15,3 +28,16 @@ export function rpcError(
  const data: RpcErrorData = { reason, ...extra };
  return { code, message, data };
 }
+
+export function transferError(
+  code: ErrorCode,
+  reason: RpcErrorReason,
+  message: string,
+  options: TransferErrorOptions,
+): RpcError {
+  return rpcError(code, reason, message, {
+    effect_state: options.effectState,
+    phase: options.phase,
+    ...(options.cleanupState ? { cleanup_state: options.cleanupState } : {}),
+  });
+}
@@ -0,0 +1,319 @@
+// One native file-drop transaction bound to an explicit page target. CDP drag
+// events are sent to the target that owns the node: root targets use top-level
+// coordinates, while OOPIF targets require coordinates local to their session.
+
+import type { RpcError, TransferEffectState } from "@/transport/types";
+import { transferError } from "./errors";
+import { resolveNodeGeometry } from "./frame-geometry";
+import type { ResolvedActionTarget } from "./interaction";
+import { type CdpRunner, isRpcError, sendToCdpTarget } from "./shared";
+import { BoundedWaitError, waitBounded } from "./transfer-transaction";
+
+const CLEANUP_TIMEOUT_MS = 1_000;
+
+type FileDropPhase = "resolve_target" | "drag_enter" | "drag_over" | "drop" | "cleanup";
+
+interface RuntimeReply {
+  result?: { value?: unknown; objectId?: string };
+  exceptionDetails?: { text?: string; exception?: { description?: string } };
+}
+
+interface DragData {
+  items: [];
+  files: string[];
+  dragOperationsMask: number;
+}
+
+export interface FileDropTransactionOptions {
+  cdp: CdpRunner;
+  actionTarget: ResolvedActionTarget;
+  files: string[];
+  timeoutMs: number;
+  signal?: AbortSignal;
+  withOverlayHidden: <T>(operation: () => Promise<T>) => Promise<T>;
+}
+
+export interface FileDropTransactionResult {
+  x: number;
+  y: number;
+}
+
+function failure(
+  code: RpcError["code"],
+  reason: "upload_mechanism_unsupported" | "file_drop_target_unavailable" | "file_drop_failed",
+  message: string,
+  effectState: TransferEffectState,
+  phase: FileDropPhase,
+): RpcError {
+  const error = transferError(code, reason, message, { effectState, phase });
+  error.data = { ...error.data, mechanism: "drop" };
+  return error;
+}
+
+function enrichFailure(
+  error: RpcError,
+  effectState: TransferEffectState,
+  phase: FileDropPhase,
+): RpcError {
+  return {
+    ...error,
+    data: {
+      ...error.data,
+      mechanism: "drop",
+      effect_state: effectState,
+      phase,
+    },
+  };
+}
+
+function messageOf(error: unknown): string {
+  return error instanceof Error ? error.message : String(error);
+}
+
+function methodUnavailable(error: unknown): boolean {
+  return /(?:method|command).*(?:not found|wasn't found|unsupported)|wasn't found|-32601/i.test(
+    messageOf(error),
+  );
+}
+
+function runtimeError(reply: RuntimeReply, fallback: string): Error | null {
+  if (!reply.exceptionDetails) return null;
+  return new Error(
+    reply.exceptionDetails.exception?.description ?? reply.exceptionDetails.text ?? fallback,
+  );
+}
+
+async function pointBelongsToTarget(
+  options: FileDropTransactionOptions,
+  x: number,
+  y: number,
+  objectGroup: string,
+): Promise<boolean> {
+  const target = options.actionTarget.cdpTarget;
+  const hit = await sendToCdpTarget<{ backendNodeId?: number; frameId?: string }>(
+    options.cdp,
+    target,
+    "DOM.getNodeForLocation",
+    { x: Math.round(x), y: Math.round(y), includeUserAgentShadowDOM: true },
+  );
+  if (typeof hit.backendNodeId !== "number") return false;
+  if (options.actionTarget.frameId && hit.frameId !== options.actionTarget.frameId) return false;
+
+  const [resolvedTarget, resolvedHit] = await Promise.all([
+    sendToCdpTarget<{ object?: { objectId?: string } }>(options.cdp, target, "DOM.resolveNode", {
+      backendNodeId: options.actionTarget.backendNodeId,
+      objectGroup,
+    }),
+    sendToCdpTarget<{ object?: { objectId?: string } }>(options.cdp, target, "DOM.resolveNode", {
+      backendNodeId: hit.backendNodeId,
+      objectGroup,
+    }),
+  ]);
+  const targetObjectId = resolvedTarget.object?.objectId;
+  const hitObjectId = resolvedHit.object?.objectId;
+  if (!targetObjectId || !hitObjectId) return false;
+
+  const reply = await sendToCdpTarget<RuntimeReply>(options.cdp, target, "Runtime.callFunctionOn", {
+    objectId: targetObjectId,
+    functionDeclaration: `function(hit) {
+        for (let node = hit; node; ) {
+          if (node === this) return true;
+          if (this.contains?.(node)) return true;
+          const root = node.getRootNode?.();
+          node = node.parentNode || (root && root !== node ? root.host : null);
+        }
+        return false;
+      }`,
+    arguments: [{ objectId: hitObjectId }],
+    returnByValue: true,
+  });
+  const error = runtimeError(reply, "failed to verify file-drop target");
+  if (error) throw error;
+  return reply.result?.value === true;
+}
+
+export async function uploadThroughFileDrop(
+  options: FileDropTransactionOptions,
+): Promise<FileDropTransactionResult | RpcError> {
+  const deadline = Date.now() + options.timeoutMs;
+  const target = options.actionTarget.cdpTarget;
+  const objectGroup = `bsk-file-drop-${crypto.randomUUID()}`;
+  const dragData: DragData = {
+    items: [],
+    files: options.files,
+    dragOperationsMask: 1,
+  };
+  let dragStarted = false;
+  let dropSent = false;
+  let dragPoint = { x: 0, y: 0 };
+  let cleanupFailed = false;
+  let outcome: FileDropTransactionResult | RpcError = failure(
+    "protocol_error",
+    "file_drop_failed",
+    "file-drop transaction ended without an outcome",
+    "none",
+    "cleanup",
+  );
+
+  try {
+    const geometry = await waitBounded(
+      resolveNodeGeometry(
+        options.cdp,
+        options.actionTarget.tab.tabId,
+        {
+          target,
+          backendNodeId: options.actionTarget.backendNodeId,
+          ...(options.actionTarget.frameId ? { frameId: options.actionTarget.frameId } : {}),
+        },
+        { scrollIntoView: true },
+      ),
+      deadline,
+      options.signal,
+      "resolving file-drop target timed out",
+    );
+    if (isRpcError(geometry)) {
+      outcome = enrichFailure(geometry, "none", "resolve_target");
+      return outcome;
+    }
+    const point = geometry.targetActionPoint;
+    dragPoint = point;
+
+    outcome = await options.withOverlayHidden(async () => {
+      try {
+        try {
+          const belongs = await waitBounded(
+            pointBelongsToTarget(options, point.x, point.y, objectGroup),
+            deadline,
+            options.signal,
+            "verifying file-drop target timed out",
+          );
+          if (!belongs) {
+            return failure(
+              "permission_denied",
+              "file_drop_target_unavailable",
+              "file-drop target is not the topmost element at its action point",
+              "none",
+              "resolve_target",
+            );
+          }
+        } catch (error) {
+          return failure(
+            error instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+            "file_drop_target_unavailable",
+            messageOf(error),
+            "none",
+            "resolve_target",
+          );
+        }
+
+        for (const [type, phase] of [
+          ["dragEnter", "drag_enter"],
+          ["dragOver", "drag_over"],
+        ] as const) {
+          try {
+            if (type === "dragEnter") dragStarted = true;
+            await waitBounded(
+              sendToCdpTarget(options.cdp, target, "Input.dispatchDragEvent", {
+                type,
+                x: point.x,
+                y: point.y,
+                data: dragData,
+              }),
+              deadline,
+              options.signal,
+              `${type} timed out`,
+            );
+          } catch (error) {
+            const unsupported = methodUnavailable(error);
+            if (type === "dragEnter" && unsupported) dragStarted = false;
+            return failure(
+              unsupported
+                ? "unsupported"
+                : error instanceof BoundedWaitError
+                  ? "timeout"
+                  : "cdp_failed",
+              unsupported ? "upload_mechanism_unsupported" : "file_drop_failed",
+              messageOf(error),
+              "none",
+              phase,
+            );
+          }
+        }
+
+        try {
+          dropSent = true;
+          await waitBounded(
+            sendToCdpTarget(options.cdp, target, "Input.dispatchDragEvent", {
+              type: "drop",
+              x: point.x,
+              y: point.y,
+              data: dragData,
+            }),
+            deadline,
+            options.signal,
+            "file drop timed out",
+          );
+          return { x: point.x, y: point.y };
+        } catch (error) {
+          outcome = failure(
+            error instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+            "file_drop_failed",
+            messageOf(error),
+            "unknown",
+            "drop",
+          );
+          return outcome;
+        }
+      } finally {
+        if (dragStarted && !dropSent) {
+          try {
+            await waitBounded(
+              sendToCdpTarget(options.cdp, target, "Input.dispatchDragEvent", {
+                type: "dragCancel",
+                x: dragPoint.x,
+                y: dragPoint.y,
+                data: dragData,
+              }),
+              Date.now() + CLEANUP_TIMEOUT_MS,
+              undefined,
+              "cancelling file drag timed out",
+            );
+          } catch {
+            cleanupFailed = true;
+          }
+        }
+      }
+    });
+    return outcome;
+  } catch (error) {
+    outcome = failure(
+      error instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+      "file_drop_target_unavailable",
+      messageOf(error),
+      "none",
+      "resolve_target",
+    );
+    return outcome;
+  } finally {
+    try {
+      await waitBounded(
+        sendToCdpTarget(options.cdp, target, "Runtime.releaseObjectGroup", { objectGroup }),
+        Date.now() + CLEANUP_TIMEOUT_MS,
+        undefined,
+        "releasing file-drop object group timed out",
+      );
+    } catch {
+      cleanupFailed = true;
+    }
+
+    const effect = isRpcError(outcome)
+      ? (outcome.data?.effect_state as TransferEffectState | undefined)
+      : "committed";
+    if (effect === "unknown" || cleanupFailed) {
+      await options.cdp.detach?.(target.tabId);
+    }
+    if (cleanupFailed && isRpcError(outcome)) {
+      outcome.data = { ...outcome.data, cleanup_state: "failed" };
+    }
+  }
+}
@@ -0,0 +1,445 @@
+// One upload transaction with an explicit browser-side commit boundary.
+// Chrome interception prevents a native chooser from escaping automation;
+// chooser events and a frame-scoped DOM probe are independent input-location
+// signals, so event delivery is not required for standard file inputs.
+
+import type { ClickResult, RpcError, TransferEffectState } from "@/transport/types";
+import { transferError } from "./errors";
+import type { ResolvedActionTarget } from "./interaction";
+import { type CdpRunner, isRpcError, sendToCdpTarget } from "./shared";
+import { BoundedWaitError, remainingMs, waitBounded } from "./transfer-transaction";
+
+const CLEANUP_TIMEOUT_MS = 1_000;
+const ACTIVATION_GRACE_MS = 1_000;
+const PROBE_INTERVAL_MS = 20;
+
+type UploadPhase =
+  | "arm_interception"
+  | "arm_input_probe"
+  | "trigger"
+  | "resolve_input"
+  | "set_files"
+  | "cleanup";
+
+interface RuntimeReply {
+  result?: { value?: unknown; objectId?: string };
+  exceptionDetails?: { text?: string; exception?: { description?: string } };
+}
+
+interface ChooserEvent {
+  frameId?: string;
+  backendNodeId?: number;
+  mode?: "selectSingle" | "selectMultiple";
+}
+
+export interface FileInputTransactionOptions {
+  cdp: CdpRunner;
+  actionTarget: ResolvedActionTarget;
+  files: string[];
+  timeoutMs: number;
+  signal?: AbortSignal;
+  trigger(): Promise<ClickResult | RpcError>;
+}
+
+export interface FileInputTransactionResult {
+  click: ClickResult;
+  multiple: boolean;
+}
+
+function runtimeError(reply: RuntimeReply, fallback: string): Error | null {
+  if (!reply.exceptionDetails) return null;
+  return new Error(
+    reply.exceptionDetails.exception?.description ?? reply.exceptionDetails.text ?? fallback,
+  );
+}
+
+function transferFailure(
+  code: RpcError["code"],
+  reason: "file_input_probe_failed" | "file_input_not_activated" | "set_file_input_failed",
+  message: string,
+  effectState: TransferEffectState,
+  phase: UploadPhase,
+): RpcError {
+  return transferError(code, reason, message, { effectState, phase });
+}
+
+function enrichFailure(
+  error: RpcError,
+  effectState: TransferEffectState,
+  phase: UploadPhase,
+): RpcError {
+  return {
+    ...error,
+    data: { ...error.data, effect_state: effectState, phase },
+  };
+}
+
+function sameTarget(
+  source: { tabId?: number; sessionId?: string },
+  target: { tabId: number; sessionId?: string },
+): boolean {
+  return source.tabId === target.tabId && source.sessionId === target.sessionId;
+}
+
+async function delay(ms: number, signal?: AbortSignal): Promise<void> {
+  await waitBounded(
+    new Promise((resolve) => setTimeout(resolve, ms)),
+    Date.now() + ms + 1,
+    signal,
+    "upload activation probe timed out",
+  );
+}
+
+async function callOnTrigger<T = RuntimeReply>(
+  options: FileInputTransactionOptions,
+  objectId: string,
+  functionDeclaration: string,
+  args: unknown[],
+  returnByValue: boolean,
+): Promise<T> {
+  return sendToCdpTarget<T>(options.cdp, options.actionTarget.cdpTarget, "Runtime.callFunctionOn", {
+    objectId,
+    functionDeclaration,
+    arguments: args.map((value) => ({ value })),
+    returnByValue,
+    awaitPromise: false,
+  });
+}
+
+export async function uploadThroughActivatedFileInput(
+  options: FileInputTransactionOptions,
+): Promise<FileInputTransactionResult | RpcError> {
+  const deadline = Date.now() + options.timeoutMs;
+  const target = options.actionTarget.cdpTarget;
+  const objectGroup = `bsk-upload-${crypto.randomUUID()}`;
+  const stateKey = `__bskUpload_${crypto.randomUUID().replaceAll("-", "")}`;
+  const chooserEvents: ChooserEvent[] = [];
+  let interceptionArmed = false;
+  let probeArmed = false;
+  let triggerObjectId: string | undefined;
+  let outcome: FileInputTransactionResult | RpcError = transferFailure(
+    "protocol_error",
+    "file_input_probe_failed",
+    "upload transaction ended without an outcome",
+    "none",
+    "cleanup",
+  );
+
+  const chooserSubscription = options.cdp.onEvent?.((source, method, raw) => {
+    if (method !== "Page.fileChooserOpened" || !sameTarget(source, target)) return;
+    const event = raw as ChooserEvent;
+    chooserEvents.push(event);
+  });
+
+  try {
+    try {
+      await waitBounded(
+        sendToCdpTarget(options.cdp, target, "Page.setInterceptFileChooserDialog", {
+          enabled: true,
+        }),
+        deadline,
+        options.signal,
+        "arming native file chooser interception timed out",
+      );
+      interceptionArmed = true;
+    } catch (err) {
+      outcome = transferFailure(
+        err instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "arm_interception",
+      );
+      return outcome;
+    }
+
+    try {
+      const resolved = await waitBounded(
+        sendToCdpTarget<{ object?: { objectId?: string } }>(
+          options.cdp,
+          target,
+          "DOM.resolveNode",
+          {
+            backendNodeId: options.actionTarget.backendNodeId,
+            objectGroup,
+          },
+        ),
+        deadline,
+        options.signal,
+        "resolving upload trigger timed out",
+      );
+      triggerObjectId = resolved.object?.objectId;
+      if (!triggerObjectId) throw new Error("DOM.resolveNode returned no trigger objectId");
+
+      const armed = await waitBounded(
+        callOnTrigger<RuntimeReply>(
+          options,
+          triggerObjectId,
+          `function(key) {
+            const doc = this.ownerDocument;
+            const owner = doc.defaultView;
+            if (!owner) return false;
+            const state = { inputs: [], listener: null };
+            Object.defineProperty(owner, key, { value: state, configurable: true });
+            state.listener = event => {
+              const path = typeof event.composedPath === "function" ? event.composedPath() : [];
+              const candidate = path[0] || event.target;
+              if (candidate && candidate.nodeType === 1 &&
+                  candidate.localName === "input" && candidate.type === "file") {
+                if (!state.inputs.includes(candidate)) state.inputs.push(candidate);
+                event.preventDefault();
+              }
+            };
+            doc.addEventListener("click", state.listener, true);
+            return true;
+          }`,
+          [stateKey],
+          true,
+        ),
+        deadline,
+        options.signal,
+        "arming frame-scoped file input probe timed out",
+      );
+      const armError = runtimeError(armed, "failed to arm file input probe");
+      if (armError || armed.result?.value !== true) {
+        throw armError ?? new Error("file input probe did not arm");
+      }
+      probeArmed = true;
+    } catch (err) {
+      outcome = transferFailure(
+        err instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "arm_input_probe",
+      );
+      return outcome;
+    }
+
+    let click: ClickResult | RpcError;
+    try {
+      click = await waitBounded(
+        options.trigger(),
+        deadline,
+        options.signal,
+        "upload trigger timed out",
+      );
+    } catch (err) {
+      outcome = transferFailure(
+        err instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "trigger",
+      );
+      return outcome;
+    }
+    if (isRpcError(click)) {
+      outcome = enrichFailure(click, "none", "trigger");
+      return outcome;
+    }
+
+    try {
+      const activationDeadline = Math.min(deadline, Date.now() + ACTIVATION_GRACE_MS);
+      let summary: { count: number; multiple: boolean } = { count: 0, multiple: false };
+      while (Date.now() < activationDeadline) {
+        if (chooserEvents.length > 0) break;
+        const reply = await callOnTrigger<RuntimeReply>(
+          options,
+          triggerObjectId,
+          `function(key) {
+            const state = this.ownerDocument.defaultView?.[key];
+            return state
+              ? { count: state.inputs.length, multiple: state.inputs[0]?.multiple === true }
+              : { count: 0, multiple: false };
+          }`,
+          [stateKey],
+          true,
+        );
+        const summaryError = runtimeError(reply, "failed to inspect activated file input");
+        if (summaryError) throw summaryError;
+        const value = reply.result?.value as { count?: unknown; multiple?: unknown } | undefined;
+        summary = {
+          count: typeof value?.count === "number" ? value.count : 0,
+          multiple: value?.multiple === true,
+        };
+        if (summary.count > 0) break;
+        await delay(Math.min(PROBE_INTERVAL_MS, remainingMs(activationDeadline)), options.signal);
+      }
+
+      if (chooserEvents.length > 1) {
+        outcome = transferFailure(
+          "unsupported",
+          "file_input_not_activated",
+          "upload trigger activated more than one file chooser",
+          "none",
+          "resolve_input",
+        );
+        return outcome;
+      }
+
+      const chooser = chooserEvents[0];
+      let backendNodeId: number | undefined;
+      let multiple = summary.multiple;
+      if (chooser) {
+        if (options.actionTarget.frameId && chooser.frameId !== options.actionTarget.frameId) {
+          outcome = transferFailure(
+            "unsupported",
+            "file_input_not_activated",
+            "upload trigger activated a file chooser in a different frame",
+            "none",
+            "resolve_input",
+          );
+          return outcome;
+        }
+        if (typeof chooser.backendNodeId !== "number") {
+          outcome = transferFailure(
+            "unsupported",
+            "file_input_not_activated",
+            "upload trigger invoked a non-input file picker",
+            "none",
+            "resolve_input",
+          );
+          return outcome;
+        }
+        backendNodeId = chooser.backendNodeId;
+        multiple = chooser.mode === "selectMultiple";
+      } else {
+        if (summary.count !== 1) {
+          outcome = transferFailure(
+            "unsupported",
+            "file_input_not_activated",
+            summary.count === 0
+              ? "upload trigger did not activate an input[type=file]"
+              : "upload trigger activated more than one input[type=file]",
+            "none",
+            "resolve_input",
+          );
+          return outcome;
+        }
+        const input = await callOnTrigger<RuntimeReply>(
+          options,
+          triggerObjectId,
+          `function(key) { return this.ownerDocument.defaultView?.[key]?.inputs[0]; }`,
+          [stateKey],
+          false,
+        );
+        const inputError = runtimeError(input, "failed to resolve activated file input object");
+        if (inputError) throw inputError;
+        if (!input.result?.objectId) throw new Error("activated file input returned no objectId");
+        const described = await sendToCdpTarget<{ node?: { backendNodeId?: number } }>(
+          options.cdp,
+          target,
+          "DOM.describeNode",
+          { objectId: input.result.objectId },
+        );
+        backendNodeId = described.node?.backendNodeId;
+        if (typeof backendNodeId !== "number") {
+          throw new Error("DOM.describeNode returned no file input backendNodeId");
+        }
+      }
+
+      if (!multiple && options.files.length !== 1) {
+        outcome = enrichFailure(
+          { code: "invalid_params", message: "file input accepts exactly one file" },
+          "none",
+          "resolve_input",
+        );
+        return outcome;
+      }
+
+      try {
+        await waitBounded(
+          sendToCdpTarget(options.cdp, target, "DOM.setFileInputFiles", {
+            files: options.files,
+            backendNodeId,
+          }),
+          deadline,
+          options.signal,
+          "setting file input files timed out",
+        );
+      } catch (err) {
+        outcome = transferFailure(
+          err instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+          "set_file_input_failed",
+          err instanceof Error ? err.message : String(err),
+          "unknown",
+          "set_files",
+        );
+        return outcome;
+      }
+      outcome = { click, multiple };
+      return outcome;
+    } catch (err) {
+      outcome = transferFailure(
+        err instanceof BoundedWaitError ? "timeout" : "cdp_failed",
+        "file_input_probe_failed",
+        err instanceof Error ? err.message : String(err),
+        "none",
+        "resolve_input",
+      );
+      return outcome;
+    }
+  } finally {
+    chooserSubscription?.dispose();
+    let cleanupFailed = false;
+    if (probeArmed && triggerObjectId) {
+      try {
+        await waitBounded(
+          callOnTrigger(
+            options,
+            triggerObjectId,
+            `function(key) {
+              const owner = this.ownerDocument.defaultView;
+              const state = owner?.[key];
+              if (state?.listener) this.ownerDocument.removeEventListener("click", state.listener, true);
+              if (owner) delete owner[key];
+            }`,
+            [stateKey],
+            true,
+          ),
+          Date.now() + CLEANUP_TIMEOUT_MS,
+          undefined,
+          "cleaning file input probe timed out",
+        );
+      } catch {
+        cleanupFailed = true;
+      }
+    }
+    if (interceptionArmed) {
+      try {
+        await waitBounded(
+          sendToCdpTarget(options.cdp, target, "Page.setInterceptFileChooserDialog", {
+            enabled: false,
+            cancel: true,
+          }),
+          Date.now() + CLEANUP_TIMEOUT_MS,
+          undefined,
+          "disabling file chooser interception timed out",
+        );
+      } catch {
+        cleanupFailed = true;
+      }
+    }
+    try {
+      await waitBounded(
+        sendToCdpTarget(options.cdp, target, "Runtime.releaseObjectGroup", { objectGroup }),
+        Date.now() + CLEANUP_TIMEOUT_MS,
+        undefined,
+        "releasing upload object group timed out",
+      );
+    } catch {
+      cleanupFailed = true;
+    }
+
+    const effect = isRpcError(outcome)
+      ? (outcome.data?.effect_state as TransferEffectState | undefined)
+      : "committed";
+    if (effect === "unknown" || cleanupFailed) {
+      await options.cdp.detach?.(target.tabId);
+    }
+    if (cleanupFailed && isRpcError(outcome)) {
+      outcome.data = { ...outcome.data, cleanup_state: "failed" };
+    }
+  }
+}
@@ -29,7 +29,10 @@ export interface NodeAddress {
 export interface ResolvedNodeGeometry {
  topVisibleRegions: Region;
  topBounds: ViewportRect;
+  /** Point in the top-level tab viewport, used by root-target input events. */
  actionPoint: Point;
+  /** Point in the addressed CDP target's viewport, used by OOPIF-local input events. */
+  targetActionPoint: Point;
 }

 function geometryError(message: string): RpcError {
@@ -262,11 +265,30 @@ export async function resolveNodeGeometry(
    if (isRpcError(localRegion)) return localRegion;

    let topVisibleRegions: Region;
+    let targetActionPoint: Point | null = null;
    if (address.frameId && graph) {
      const projection = await resolveFrameProjection(cdp, graph, address.frameId);
      if (!projection)
        return geometryError(`could not resolve frame geometry for ${address.frameId}`);
      topVisibleRegions = projectRegionToViewport(localRegion, projection);
+      if (address.target.sessionId) {
+        const localViewport = projection.edges[0]?.sourceViewport ?? projection.topViewport;
+        const localVisibleRegions = localRegion
+          .map((polygon) =>
+            clipPolygon(
+              polygon,
+              rectPolygon({
+                x: 0,
+                y: 0,
+                w: localViewport.width,
+                h: localViewport.height,
+              }),
+            ),
+          )
+          .filter((polygon) => polygon.length >= 3);
+        const localActionRegion = largestRegion(localVisibleRegions);
+        targetActionPoint = localActionRegion ? polygonCentroid(localActionRegion) : null;
+      }
    } else {
      const viewport = await targetViewport(cdp, address.target);
      if (!viewport) return geometryError("could not resolve top viewport geometry");
@@ -283,7 +305,11 @@ export async function resolveNodeGeometry(
    if (!topBounds || !actionPoint) {
      return { code: "permission_denied", message: "element not visible" };
    }
-    return { topVisibleRegions, topBounds, actionPoint };
+    if (address.target.sessionId && !targetActionPoint) {
+      return { code: "permission_denied", message: "element not visible in its target" };
+    }
+    targetActionPoint ??= actionPoint;
+    return { topVisibleRegions, topBounds, actionPoint, targetActionPoint };
  } catch (error) {
    return geometryError(error instanceof Error ? error.message : String(error));
  }
@@ -40,6 +40,7 @@ import {
  enforceAgentWindow,
  isRpcError,
  lookupSession,
+  type ResolvedTargetTab,
  resolveTargetTab,
 } from "./shared";
 import { resolveSnapshotRef } from "./snapshot-ref";
@@ -56,6 +57,15 @@ export interface InteractionDeps {
  keepOverlayBypassAfterHover?: boolean;
 }

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

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

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

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

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

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

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

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

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

@@ -137,9 +180,11 @@ async function sendRecordStartWithAck(
  tabId: number,
  msg: RecordStartMessage,
  sendToTab: RecordDeps["sendToTab"],
+  cancelled?: () => boolean,
 ): Promise<void> {
  let lastError: unknown;
  for (let attempt = 0; attempt < RECORD_START_RETRIES; attempt += 1) {
+    if (cancelled?.()) throw new Error("record start cancelled");
    try {
      const response = await sendToTab(tabId, msg);
      if (isRecordStartAck(response)) return;
@@ -147,6 +192,7 @@ async function sendRecordStartWithAck(
    } catch (err) {
      lastError = err;
    }
+    if (cancelled?.()) throw new Error("record start cancelled");
    if (attempt + 1 < RECORD_START_RETRIES) {
      await sleep(RECORD_START_RETRY_DELAY_MS);
    }
@@ -154,19 +200,83 @@ async function sendRecordStartWithAck(
  throw lastError ?? new Error("failed to start recording in content script");
 }

-function buildTrace(recording: ActiveRecording): Trace {
-  const { pages, steps } = reduceTraceSteps(recording.steps, recording.startUrl);
-  const startUrl = resolveTraceStartUrl(recording.steps, recording.startUrl, pages);
+function negotiatedTraceVersion(params: RecordStartParams): 2 | 3 | RpcError {
+  if (params.trace_version === undefined) return 2;
+  if (params.trace_version === TRACE_VERSION_V3) return 3;
  return {
-    ...(recording.purpose ? { purpose: recording.purpose } : {}),
-    recorded_at: new Date().toISOString(),
-    started_at: recording.startedAt,
-    entry: { start_url: startUrl },
-    pages,
-    steps,
+    code: "invalid_params",
+    message: `unsupported trace_version ${params.trace_version}; supported values are omitted (v2) or ${TRACE_VERSION_V3} (v3)`,
  };
 }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

-  const trace = await finishRecording(params.session_id, deps);
+  const trace = await finishRecording(params.session_id, deps, "cli_stop");
  if (!trace) {
    return {
      code: "protocol_error",
@@ -785,9 +1100,9 @@ export async function handleRecordAwait(
    return { code: "cancelled", message: "record_await aborted" };
  }

-  const outcome = await new Promise<{ trace: Trace } | { error: RpcError }>((resolve) => {
+  const outcome = await new Promise<{ trace: RecordedTrace } | { error: RpcError }>((resolve) => {
    let settled = false;
-    const finish = (result: { trace: Trace } | { error: RpcError }) => {
+    const finish = (result: { trace: RecordedTrace } | { error: RpcError }) => {
      if (settled) return;
      settled = true;
      if (timer) clearTimeout(timer);
@@ -829,6 +1144,8 @@ export function clearRecordingForSession(sessionId: string): void {
  }
  void clearRearmTimersForRecording(recording, getDefaultDeps());
  if (!recording.settled) {
+    getDefaultDeps().frameCoordinator?.cancel(recording.requestId);
+    recording.observation?.cancel();
    recording.settled = true;
    recording.rejectFinish(new Error("recording cleared"));
  }
@@ -76,6 +76,7 @@ export interface SessionStopResult {
 }

 export interface SessionStopDeps {
+  signal?: AbortSignal;
  cdp?: {
    detachSession(sessionId: string): Promise<void>;
  };
@@ -177,6 +178,9 @@ export async function handleSessionStop(
      message: `session ${params.session_id} unknown`,
    };
  }
+  if (deps.signal?.aborted) {
+    return { code: "cancelled", message: "session_stop aborted before teardown" };
+  }

  // Step 1: auto-return borrowed tabs. Iterate over a snapshot of the
  // ids so deletions during iteration do not break the Map iterator.
@@ -187,6 +191,7 @@ export async function handleSessionStop(
    try {
      const tabManagement = {
        ...(deps.tabManagement ?? {}),
+        signal: deps.signal,
        isAgentWindowId:
          deps.tabManagement?.isAgentWindowId ??
          ((windowId: number) => manager.findByWindowId(windowId) !== null),
@@ -214,6 +219,17 @@ export async function handleSessionStop(
    }
  }

+  if (deps.signal?.aborted) {
+    const nonCancelFailures = returnFailures?.filter((failure) => failure.code !== "cancelled");
+    if (nonCancelFailures && nonCancelFailures.length > 0) {
+      return {
+        ...(returnedTabIds.length > 0 ? { returned_tab_ids: returnedTabIds } : {}),
+        return_failures: nonCancelFailures,
+      };
+    }
+    return { code: "cancelled", message: "session_stop aborted during tab return" };
+  }
+
  const result: SessionStopResult = {};
  if (returnedTabIds.length > 0) result.returned_tab_ids = returnedTabIds;
  if (returnFailures && returnFailures.length > 0) {
@@ -233,6 +249,10 @@ export async function handleSessionStop(
  // Step 3: detach CDP sessions this session opened (no-op if none).
  await deps.cdp?.detachSession(params.session_id);

+  if (deps.signal?.aborted) {
+    return { code: "cancelled", message: "session_stop aborted before window close" };
+  }
+
  // Step 4: close the Agent Window and drop the context.
  await manager.stop(params.session_id);

@@ -53,6 +53,7 @@ export type { DialogCursor };
 export interface CdpRunner {
  send<T = unknown>(tabId: number, method: string, params?: object): Promise<T>;
  sendToTarget?<T = unknown>(target: CdpTarget, method: string, params?: object): Promise<T>;
+  detach?(tabId: number): Promise<void>;
  getFrameGraph?(tabId: number): Promise<CdpFrameGraph>;
  ensureAttachedToUrl?(tabId: number, expectedUrl: string | undefined): Promise<void>;
  trackSessionTab?(sessionId: string, tabId: number): void;
@@ -0,0 +1,42 @@
+// Shared time boundary for browser-side file-transfer transactions. Concrete
+// upload/download mechanisms own their state machines and effect semantics.
+
+export class BoundedWaitError extends Error {
+  constructor(
+    readonly kind: "timeout" | "aborted",
+    message: string,
+  ) {
+    super(message);
+  }
+}
+
+export function remainingMs(deadline: number): number {
+  return Math.max(0, deadline - Date.now());
+}
+
+export async function waitBounded<T>(
+  promise: Promise<T>,
+  deadline: number,
+  signal: AbortSignal | undefined,
+  timeoutMessage: string,
+): Promise<T> {
+  const remaining = remainingMs(deadline);
+  if (signal?.aborted) throw new BoundedWaitError("aborted", "file transfer aborted");
+  if (remaining === 0) throw new BoundedWaitError("timeout", timeoutMessage);
+
+  let timer: ReturnType<typeof setTimeout> | undefined;
+  let onAbort: (() => void) | undefined;
+  const boundary = new Promise<never>((_resolve, reject) => {
+    timer = setTimeout(() => reject(new BoundedWaitError("timeout", timeoutMessage)), remaining);
+    if (signal) {
+      onAbort = () => reject(new BoundedWaitError("aborted", "file transfer aborted"));
+      signal.addEventListener("abort", onAbort, { once: true });
+    }
+  });
+  try {
+    return await Promise.race([promise, boundary]);
+  } finally {
+    if (timer) clearTimeout(timer);
+    if (signal && onAbort) signal.removeEventListener("abort", onAbort);
+  }
+}
@@ -0,0 +1,85 @@
+// Upload orchestration: validate the session-scoped request, resolve its click
+// target, then delegate the browser protocol transaction to the file-input
+// transaction module.
+
+import {
+  type CaptureSuppressSendToTab,
+  withExtensionOverlayHidden,
+} from "@/lib/capture-suppress-bridge";
+import type { SessionManager } from "@/session-manager/manager";
+import type { RpcError, UploadParams, UploadResult } from "@/transport/types";
+import { uploadThroughFileDrop } from "./file-drop-transaction";
+import { uploadThroughActivatedFileInput } from "./file-input-transaction";
+import { clickResolvedTarget, type InteractionDeps, resolveActionTarget } from "./interaction";
+import {
+  type CdpRunner,
+  enforceAgentWindow,
+  isRpcError,
+  lookupSession,
+  resolveTargetTab,
+} from "./shared";
+
+const DEFAULT_TIMEOUT_MS = 120_000;
+
+export interface UploadDeps extends InteractionDeps {
+  cdp: CdpRunner;
+  sendToTab?: CaptureSuppressSendToTab;
+}
+
+export async function handleUpload(
+  manager: SessionManager,
+  params: UploadParams,
+  deps: UploadDeps,
+): Promise<UploadResult | RpcError> {
+  const ctx = lookupSession(manager, params, "upload");
+  if (isRpcError(ctx)) return ctx;
+  const target = await resolveTargetTab(manager, ctx, params.tab_id, deps.tabsApi);
+  if (isRpcError(target)) return target;
+  const denied = enforceAgentWindow(ctx, target, "upload");
+  if (denied) return denied;
+  if (
+    params.files.length === 0 ||
+    params.files.length > 20 ||
+    params.files.some((file) => !file.staged_path)
+  ) {
+    return { code: "invalid_params", message: "upload requires daemon-staged files" };
+  }
+  const address = await resolveActionTarget(deps.cdp, ctx, target, params, "upload");
+  if (isRpcError(address)) return address;
+  const timeoutMs = params.timeout_ms ?? DEFAULT_TIMEOUT_MS;
+  const files = params.files.map((file) => file.staged_path as string);
+  const mode = params.mode ?? "input";
+  let usedRef = address.usedRef;
+  let usedSelector = address.usedSelector;
+  if (mode === "drop") {
+    deps.cdp.trackSessionTab?.(ctx.sessionId, target.tabId);
+    const transaction = await uploadThroughFileDrop({
+      cdp: deps.cdp,
+      actionTarget: address,
+      files,
+      timeoutMs,
+      signal: deps.signal,
+      withOverlayHidden: (operation) =>
+        withExtensionOverlayHidden(target.tabId, operation, deps.sendToTab),
+    });
+    if (isRpcError(transaction)) return transaction;
+  } else {
+    const transaction = await uploadThroughActivatedFileInput({
+      cdp: deps.cdp,
+      actionTarget: address,
+      files,
+      timeoutMs,
+      signal: deps.signal,
+      trigger: () => clickResolvedTarget(ctx, address, {}, deps),
+    });
+    if (isRpcError(transaction)) return transaction;
+    usedRef = transaction.click.used_ref;
+    usedSelector = transaction.click.used_selector;
+  }
+  return {
+    tab_id: target.tabId,
+    used_ref: usedRef,
+    used_selector: usedSelector,
+    file_names: params.files.map((file) => file.name),
+  };
+}
@@ -1,6 +1,6 @@
 import { describe, expect, it, vi } from "vitest";
 import { OVERLAY_HOST_MARKER_ATTR, OVERLAY_HOST_NAME } from "../../../lib/overlay-bridge";
-import { captureViewModel, collectOverlayExcludedBackendIds } from "../capture";
+import { captureViewModel, collectOverlayExcludedBackendIds, probeHoverSurfaces } from "../capture";

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

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

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

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

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

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

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

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

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

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

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

 import type { Rect, Viewport } from "@browser-skill/vom";
 import { evaluateHoverTrigger } from "@/lib/hover-trigger-policy";
 import { isOverlayHostNode, OVERLAY_HOST_SELECTOR } from "../../lib/overlay-bridge";
 import { childFrameProjection, type GeometryProjection, projectRectToViewport } from "../geometry";
 import type { CdpRunner } from "../shared";
+import { clearHover, ProbeBudget, waitForHover } from "./hover-perception";

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

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

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

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

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

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

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

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

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

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

-function frameOwnerNode(captured: CapturedViewModel, frame: CdpFrame): CapturedNode | undefined {
-  if (frame.ownerBackendNodeId === undefined) return undefined;
-  const parentNodes = frame.parentFrameId
-    ? captured.frameNodes?.get(frame.parentFrameId)
-    : captured.nodes;
-  return parentNodes?.find((node) => node.backendNodeId === frame.ownerBackendNodeId);
-}
-
 async function captureMissingFrameDocuments(
  cdp: CdpRunner,
  tabId: number,
@@ -65,14 +59,20 @@ async function captureMissingFrameDocuments(

  for (const frame of graph.frames) {
    if (!frame.target.sessionId || captured.frameNodes.has(frame.frameId)) continue;
-    const owner = frameOwnerNode(captured, frame);
-    if (!owner?.rect || frame.ownerBackendNodeId === undefined) continue;
    try {
      const child = await captureViewModel(cdpRunnerForTarget(cdp, frame.target), tabId, {
        signal,
      });
-      const projection = await resolveFrameProjection(cdp, graph, frame.frameId);
-      if (!projection) continue;
+      let projection: GeometryProjection | null = null;
+      try {
+        projection = await resolveFrameProjection(cdp, graph, frame.frameId);
+      } catch (err) {
+        if (isAbortError(err)) throw err;
+        console.debug("[bsk observation] child frame geometry projection failed", {
+          frameId: frame.frameId,
+          err,
+        });
+      }
      const rootFrameId = child.rootFrameId ?? frame.frameId;
      const childFrames = child.frameNodes ?? new Map<string, CapturedNode[]>();
      if (!childFrames.has(rootFrameId)) childFrames.set(rootFrameId, child.nodes);
@@ -85,11 +85,13 @@ async function captureMissingFrameDocuments(
      for (const [childFrameId, nodes] of childFrames) {
        captured.frameNodes.set(childFrameId, transformFrameNodes(nodes, projection));
      }
-      captured.iframeNodes.set(
-        frame.ownerBackendNodeId,
-        captured.frameNodes.get(frame.frameId) ?? [],
-      );
-      captured.frameOwnerBackendNodeIds.set(frame.frameId, frame.ownerBackendNodeId);
+      if (frame.ownerBackendNodeId !== undefined) {
+        captured.iframeNodes.set(
+          frame.ownerBackendNodeId,
+          captured.frameNodes.get(frame.frameId) ?? [],
+        );
+        captured.frameOwnerBackendNodeIds.set(frame.frameId, frame.ownerBackendNodeId);
+      }
      if (frame.parentFrameId) captured.frameParentIds.set(frame.frameId, frame.parentFrameId);
      for (const [childFrameId, ownerBackendNodeId] of child.frameOwnerBackendNodeIds ?? []) {
        captured.frameOwnerBackendNodeIds.set(childFrameId, ownerBackendNodeId);
@@ -77,9 +77,12 @@ export function buildFrameDocuments<T extends FrameOwnedAxNode>(
 ): FrameDocument<T>[] {
  const frames = frameList(graph, batches, captured);
  const frameById = new Map(frames.map((frame) => [frame.frameId, frame]));
+  const rootFrameId = graph?.rootFrameId ?? captured.rootFrameId ?? frames[0]?.frameId;
+  const domNodesForFrame = (frameId: string): CapturedNode[] =>
+    captured.frameNodes?.get(frameId) ?? (frameId === rootFrameId ? captured.nodes : []);
  const backendOwner = new Map<string, string>();
  for (const frame of frames) {
-    for (const node of captured.frameNodes?.get(frame.frameId) ?? []) {
+    for (const node of domNodesForFrame(frame.frameId)) {
      backendOwner.set(targetBackendKey(frame.target, node.backendNodeId), frame.frameId);
    }
  }
@@ -165,6 +168,6 @@ export function buildFrameDocuments<T extends FrameOwnedAxNode>(
    ...frame,
    contextScopeId: frame.frameId,
    axNodes: axNodesByFrame.get(frame.frameId) ?? [],
-    domNodes: captured.frameNodes?.get(frame.frameId) ?? [],
+    domNodes: domNodesForFrame(frame.frameId),
  }));
 }
@@ -0,0 +1,125 @@
+import type { CdpRunner } from "../shared";
+
+function abortError(): Error {
+  const error = new Error("hover perception aborted");
+  error.name = "AbortError";
+  return error;
+}
+
+export async function waitForHover(ms: number, signal?: AbortSignal): Promise<void> {
+  if (signal?.aborted) throw abortError();
+  await new Promise<void>((resolve, reject) => {
+    const timer = setTimeout(() => {
+      signal?.removeEventListener("abort", onAbort);
+      resolve();
+    }, ms);
+    const onAbort = () => {
+      clearTimeout(timer);
+      signal?.removeEventListener("abort", onAbort);
+      reject(abortError());
+    };
+    signal?.addEventListener("abort", onAbort, { once: true });
+  });
+}
+
+export async function clearHover(cdp: CdpRunner, tabId: number): Promise<void> {
+  await cdp
+    .send(tabId, "Input.dispatchMouseEvent", {
+      type: "mouseMoved",
+      x: -10,
+      y: -10,
+    })
+    .catch(() =>
+      cdp.send(tabId, "Input.dispatchMouseEvent", { type: "mouseMoved", x: 0, y: 0 }).catch(() => {
+        // Best effort cleanup.
+      }),
+    );
+}
+
+/**
+ * Wall-clock budget for a probe phase.
+ *
+ * Callers ask whether the *next* candidate still fits before starting it,
+ * rather than checking elapsed time at the top of the loop. A top-of-loop
+ * check lets a candidate start with 1ms of budget left and then run to
+ * completion, overshooting by a full settle window.
+ */
+export class ProbeBudget {
+  private readonly startedAt = Date.now();
+
+  constructor(private readonly totalMs: number) {}
+
+  get elapsedMs(): number {
+    return Date.now() - this.startedAt;
+  }
+
+  /** True when a candidate costing `estimatedMs` still fits in the budget. */
+  canAfford(estimatedMs: number): boolean {
+    return this.elapsedMs + estimatedMs <= this.totalMs;
+  }
+}
+
+export type OverlayBypass = (tabId: number, enabled: boolean) => Promise<void>;
+
+export interface OverlayBypassScopeOptions {
+  /**
+   * Called when the overlay could not be restored. Defaults to `console.error`
+   * so a stuck-bypassed overlay is never silent; tests inject a spy.
+   */
+  onRestoreFailure?: (error: unknown) => void;
+}
+
+const overlayBypassDepth = new Map<number, number>();
+
+/**
+ * Runs `body` with the agent overlay bypassed, restoring it afterwards.
+ *
+ * Reference counted per tab so nested probe phases share a single bypass span
+ * instead of toggling the overlay once per phase. Restore failures are
+ * reported rather than swallowed, and the depth is released even when restore
+ * throws so a failure cannot pin the overlay off for the tab's lifetime.
+ */
+export async function withOverlayBypass<T>(
+  bypass: OverlayBypass | undefined,
+  tabId: number,
+  body: () => Promise<T>,
+  options: OverlayBypassScopeOptions = {},
+): Promise<T> {
+  if (!bypass) return body();
+
+  const depth = overlayBypassDepth.get(tabId) ?? 0;
+  overlayBypassDepth.set(tabId, depth + 1);
+  if (depth === 0) {
+    try {
+      await bypass(tabId, true);
+    } catch (error) {
+      // Failing to hide the overlay only risks probing our own UI, so continue.
+      console.debug("[bsk hover] overlay bypass could not be enabled", error);
+    }
+  }
+
+  try {
+    return await body();
+  } finally {
+    const current = overlayBypassDepth.get(tabId) ?? 1;
+    if (current <= 1) {
+      overlayBypassDepth.delete(tabId);
+      try {
+        await bypass(tabId, false);
+      } catch (error) {
+        (options.onRestoreFailure ?? defaultRestoreFailure)(error);
+      }
+    } else {
+      overlayBypassDepth.set(tabId, current - 1);
+    }
+  }
+}
+
+function defaultRestoreFailure(error: unknown): void {
+  console.error("[bsk hover] agent overlay could not be restored after probing", error);
+}
+
+/** Test seam: drops any bypass depth left behind by a crashed probe. */
+export function resetOverlayBypassDepth(): void {
+  overlayBypassDepth.clear();
+}
@@ -0,0 +1,307 @@
+import { isVomReferenceNode } from "@browser-skill/vom";
+import { type CdpRunner, sendToCdpTarget } from "../shared";
+import type { FrameDocument, FrameOwnedAxNode } from "./frame-document";
+import { clearHover, ProbeBudget, waitForHover } from "./hover-perception";
+import { stableIdentifierName } from "./semantic-graph/name-evidence";
+import { frameBackendKey, type ResolvedSemanticGraph } from "./semantic-graph/types";
+
+const MAX_TOOLTIP_CANDIDATES = 8;
+const MAX_TOOLTIP_PROBE_MS = 2_400;
+const TOOLTIP_SETTLE_MS = 250;
+const CACHE_TTL_MS = 5 * 60_000;
+/**
+ * Misses expire sooner than hits: a control that gains a tooltip once the app
+ * finishes booting should still be discoverable, but not at the cost of
+ * re-probing every unlabelled control on every observation.
+ */
+const MISS_CACHE_TTL_MS = 60_000;
+const MAX_CACHE_ENTRIES = 500;
+const FORM_CONTROL_TAGS = new Set(["input", "select", "textarea"]);
+
+interface TooltipCacheEntry {
+  /** `null` records "probed, revealed no tooltip" so the miss is not re-paid. */
+  name: string | null;
+  expiresAt: number;
+}
+
+interface TooltipCandidate<T extends FrameOwnedAxNode> {
+  document: FrameDocument<T>;
+  backendNodeId: number;
+  x: number;
+  y: number;
+  stableIdentifier: boolean;
+}
+
+export interface TooltipNameProbeOptions {
+  signal?: AbortSignal;
+}
+
+const tooltipCache = new Map<string, TooltipCacheEntry>();
+
+function cacheKey<T extends FrameOwnedAxNode>(
+  document: FrameDocument<T>,
+  backendNodeId: number,
+): string {
+  return `${document.target.tabId}\u0000${document.frameId}\u0000${document.url ?? ""}\u0000${backendNodeId}`;
+}
+
+/** Returns the cache entry, or `undefined` when this control was never probed. */
+function cachedEntry<T extends FrameOwnedAxNode>(
+  document: FrameDocument<T>,
+  backendNodeId: number,
+): TooltipCacheEntry | undefined {
+  const key = cacheKey(document, backendNodeId);
+  const entry = tooltipCache.get(key);
+  if (!entry) return undefined;
+  if (entry.expiresAt <= Date.now()) {
+    tooltipCache.delete(key);
+    return undefined;
+  }
+  return entry;
+}
+
+function storeName<T extends FrameOwnedAxNode>(
+  document: FrameDocument<T>,
+  backendNodeId: number,
+  name: string | null,
+): void {
+  if (tooltipCache.size >= MAX_CACHE_ENTRIES) {
+    const oldest = tooltipCache.keys().next().value;
+    if (oldest !== undefined) tooltipCache.delete(oldest);
+  }
+  tooltipCache.set(cacheKey(document, backendNodeId), {
+    name,
+    expiresAt: Date.now() + (name === null ? MISS_CACHE_TTL_MS : CACHE_TTL_MS),
+  });
+}
+
+function tooltipCollectorFunction(): string {
+  return `function() {
+    const ownRoot = this && typeof this.getRootNode === "function" ? this.getRootNode() : null;
+    const roots = ownRoot && ownRoot !== document ? [ownRoot, document] : [document];
+    const items = [];
+    const seen = new Set();
+    for (const root of roots) {
+      for (const el of Array.from(root.querySelectorAll("[role='tooltip']"))) {
+        const style = getComputedStyle(el);
+        const rect = el.getBoundingClientRect();
+        if (rect.width <= 0 || rect.height <= 0) continue;
+        if (style.display === "none" || style.visibility === "hidden" || style.opacity === "0") continue;
+        const text = String(el.getAttribute("aria-label") || el.getAttribute("title") || el.textContent || "")
+          .replace(/\\s+/g, " ")
+          .trim();
+        if (!text || text.length > 160 || seen.has(text)) continue;
+        seen.add(text);
+        items.push(text);
+      }
+    }
+    return items.slice(0, 20);
+  }`;
+}
+
+function cleanTooltipDiff(before: string[], after: string[]): string | undefined {
+  const existing = new Set(before.map((value) => value.toLowerCase()));
+  const added = [...new Set(after.map((value) => value.replace(/\s+/g, " ").trim()))].filter(
+    (value) => value && !existing.has(value.toLowerCase()),
+  );
+  return added.length === 1 ? added[0] : undefined;
+}
+
+function candidates<T extends FrameOwnedAxNode>(
+  documents: FrameDocument<T>[],
+  graph: ResolvedSemanticGraph,
+): TooltipCandidate<T>[] {
+  const documentByFrame = new Map(documents.map((document) => [document.frameId, document]));
+  const byFrame = new Map<string, TooltipCandidate<T>[]>();
+  for (const node of graph.nodes.values()) {
+    if (
+      node.vom.name ||
+      FORM_CONTROL_TAGS.has(node.dom?.tag.toLowerCase() ?? "") ||
+      !node.referenceable ||
+      node.backendNodeId === undefined ||
+      !isVomReferenceNode({
+        ...node.vom,
+        id: 0,
+        parentId: null,
+        backendNodeId: node.backendNodeId,
+        frameId: node.frameId,
+        referenceable: true,
+      })
+    ) {
+      continue;
+    }
+    const document = documentByFrame.get(node.frameId);
+    const rect = node.dom?.rect;
+    if (!document || !rect || rect.w <= 0 || rect.h <= 0) continue;
+    if (
+      rect.x + rect.w <= 0 ||
+      rect.y + rect.h <= 0 ||
+      rect.x >= graph.viewport.width ||
+      rect.y >= graph.viewport.height
+    ) {
+      continue;
+    }
+    if (
+      node.vom.disabled ||
+      node.vom.inert ||
+      node.vom.pointerEvents === "none" ||
+      node.vom.sensitive
+    ) {
+      continue;
+    }
+    const frameCandidates = byFrame.get(node.frameId) ?? [];
+    frameCandidates.push({
+      document,
+      backendNodeId: node.backendNodeId,
+      x: (Math.max(0, rect.x) + Math.min(graph.viewport.width, rect.x + rect.w)) / 2,
+      y: (Math.max(0, rect.y) + Math.min(graph.viewport.height, rect.y + rect.h)) / 2,
+      stableIdentifier: stableIdentifierName(node.dom?.attrs ?? {}) !== undefined,
+    });
+    byFrame.set(node.frameId, frameCandidates);
+  }
+
+  const out: TooltipCandidate<T>[] = [];
+  for (const stableIdentifier of [true, false]) {
+    const queues = documents.map((document) =>
+      (byFrame.get(document.frameId) ?? []).filter(
+        (candidate) => candidate.stableIdentifier === stableIdentifier,
+      ),
+    );
+    for (let index = 0; queues.some((queue) => index < queue.length); index += 1) {
+      for (const queue of queues) {
+        const candidate = queue[index];
+        if (candidate) out.push(candidate);
+      }
+    }
+  }
+  return out;
+}
+
+async function executionContextId<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+): Promise<number | undefined> {
+  const result = await sendToCdpTarget<{ executionContextId?: number }>(
+    cdp,
+    document.target,
+    "Page.createIsolatedWorld",
+    {
+      frameId: document.frameId,
+      worldName: "bsk-vom-tooltip",
+      grantUniveralAccess: false,
+    },
+  );
+  return result.executionContextId;
+}
+
+async function resolvedObjectId<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+  contextId: number,
+  backendNodeId: number,
+): Promise<string | undefined> {
+  const result = await sendToCdpTarget<{
+    object?: { objectId?: string };
+  }>(cdp, document.target, "DOM.resolveNode", {
+    backendNodeId,
+    executionContextId: contextId,
+  });
+  return result.object?.objectId;
+}
+
+async function tooltipTexts<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+  objectId: string,
+): Promise<string[]> {
+  const result = await sendToCdpTarget<{
+    result?: { value?: string[] };
+  }>(cdp, document.target, "Runtime.callFunctionOn", {
+    functionDeclaration: tooltipCollectorFunction(),
+    objectId,
+    returnByValue: true,
+  });
+  return result.result?.value ?? [];
+}
+
+async function releaseObject<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  document: FrameDocument<T>,
+  objectId: string,
+): Promise<void> {
+  await sendToCdpTarget(cdp, document.target, "Runtime.releaseObject", { objectId }).catch(
+    () => undefined,
+  );
+}
+
+export async function probeTooltipNames<T extends FrameOwnedAxNode>(
+  cdp: CdpRunner,
+  tabId: number,
+  documents: FrameDocument<T>[],
+  graph: ResolvedSemanticGraph,
+  options: TooltipNameProbeOptions = {},
+): Promise<Map<string, string>> {
+  const names = new Map<string, string>();
+  const pending: TooltipCandidate<T>[] = [];
+  for (const candidate of candidates(documents, graph)) {
+    const cached = cachedEntry(candidate.document, candidate.backendNodeId);
+    if (cached) {
+      // A cached miss is still a decision: skip the control instead of re-probing.
+      if (cached.name !== null) {
+        names.set(
+          frameBackendKey(candidate.document.frameId, candidate.backendNodeId),
+          cached.name,
+        );
+      }
+    } else if (pending.length < MAX_TOOLTIP_CANDIDATES) {
+      pending.push(candidate);
+    }
+  }
+  if (pending.length === 0) return names;
+
+  const budget = new ProbeBudget(MAX_TOOLTIP_PROBE_MS);
+  const contexts = new Map<string, number>();
+  try {
+    for (const candidate of pending) {
+      if (options.signal?.aborted) throw new DOMException("observation aborted", "AbortError");
+      if (!budget.canAfford(TOOLTIP_SETTLE_MS)) break;
+      let objectId: string | undefined;
+      try {
+        let contextId = contexts.get(candidate.document.frameId);
+        if (contextId === undefined) {
+          contextId = await executionContextId(cdp, candidate.document);
+          if (contextId === undefined) continue;
+          contexts.set(candidate.document.frameId, contextId);
+        }
+        objectId = await resolvedObjectId(
+          cdp,
+          candidate.document,
+          contextId,
+          candidate.backendNodeId,
+        );
+        if (!objectId) continue;
+        await clearHover(cdp, tabId);
+        const before = await tooltipTexts(cdp, candidate.document, objectId);
+        await cdp.send(tabId, "Input.dispatchMouseEvent", {
+          type: "mouseMoved",
+          x: candidate.x,
+          y: candidate.y,
+        });
+        await waitForHover(TOOLTIP_SETTLE_MS, options.signal);
+        const after = await tooltipTexts(cdp, candidate.document, objectId);
+        const name = cleanTooltipDiff(before, after);
+        storeName(candidate.document, candidate.backendNodeId, name ?? null);
+        if (!name) continue;
+        names.set(frameBackendKey(candidate.document.frameId, candidate.backendNodeId), name);
+      } catch (error) {
+        if (error instanceof Error && error.name === "AbortError") throw error;
+      } finally {
+        if (objectId) await releaseObject(cdp, candidate.document, objectId);
+        await clearHover(cdp, tabId);
+      }
+    }
+  } finally {
+    await clearHover(cdp, tabId);
+  }
+  return names;
+}
@@ -0,0 +1,101 @@
+import type { Rect, RenderedRef, VomResult } from "@browser-skill/vom";
+import type { CdpTarget } from "@/browser-driver/frame-graph";
+import { readRecordingDocumentIdentity } from "@/shared/recording-document-identity";
+import type { CapturedSurfaceProbe } from "./capture";
+import type { CapturedFrameDocument, FrameAxNode } from "./frame-capture";
+
+/** Frame identity needed to resolve an `@eN` that lives in an iframe. */
+export interface CaptureVomFrame {
+  frameId: string;
+  target: CdpTarget;
+  parentFrameId?: string;
+  ownerBackendNodeId?: number;
+  /** BrowserSkill-generated identity for the recording agent in this Document. */
+  recordingDocumentId?: string;
+}
+
+/** Allowlisted geometry used to match a recorded action to a rendered ref. */
+export interface CaptureVomMatchNode {
+  frameId: string;
+  backendNodeId: number;
+  tag: string;
+  /** Top-level viewport-relative geometry. */
+  rect: Rect | null;
+  /** Frame-local viewport-relative geometry, when available. */
+  localRect?: Rect | null;
+}
+
+/**
+ * Raw AX/DOM trees are never returned. When `redactValues` is enabled by the
+ * caller, form values in `text` are masked as well.
+ */
+export interface CaptureVomObservationResult {
+  text: string;
+  refs: RenderedRef[];
+  truncated: boolean;
+  rootFrameId: string;
+  frames: CaptureVomFrame[];
+  matchNodes: CaptureVomMatchNode[];
+  surfaceProbes?: CapturedSurfaceProbe[];
+  /**
+   * Whether this observation actively hovered the page, and whether that
+   * revealed content the static tree does not contain. Lets callers judge how
+   * far the page may have drifted from the returned snapshot.
+   */
+  hoverProbe?: HoverProbeReport;
+}
+
+export interface HoverProbeReport {
+  performed: boolean;
+  revealedContent: boolean;
+}
+
+function projectFrames(documents: CapturedFrameDocument<FrameAxNode>[]): CaptureVomFrame[] {
+  return documents.map((document) => {
+    let recordingDocumentId: string | undefined;
+    for (const node of document.domNodes) {
+      recordingDocumentId = readRecordingDocumentIdentity(node.attrs);
+      if (recordingDocumentId) break;
+    }
+    return {
+      frameId: document.frameId,
+      target: document.target,
+      ...(document.parentFrameId ? { parentFrameId: document.parentFrameId } : {}),
+      ...(document.ownerBackendNodeId !== undefined
+        ? { ownerBackendNodeId: document.ownerBackendNodeId }
+        : {}),
+      ...(recordingDocumentId ? { recordingDocumentId } : {}),
+    };
+  });
+}
+
+function projectMatchNodes(documents: CapturedFrameDocument<FrameAxNode>[]): CaptureVomMatchNode[] {
+  return documents.flatMap((document) =>
+    document.domNodes.map((node) => ({
+      frameId: document.frameId,
+      backendNodeId: node.backendNodeId,
+      tag: node.tag,
+      rect: node.rect,
+      ...(node.localRect !== undefined ? { localRect: node.localRect } : {}),
+    })),
+  );
+}
+
+export function projectRecordSafeObservation(input: {
+  rootFrameId: string;
+  frameDocuments: CapturedFrameDocument<FrameAxNode>[];
+  rendered: VomResult;
+  surfaceProbes?: CapturedSurfaceProbe[];
+  hoverProbe?: HoverProbeReport;
+}): CaptureVomObservationResult {
+  return {
+    text: input.rendered.text,
+    refs: input.rendered.refs,
+    truncated: input.rendered.truncated,
+    rootFrameId: input.rootFrameId,
+    frames: projectFrames(input.frameDocuments),
+    matchNodes: projectMatchNodes(input.frameDocuments),
+    surfaceProbes: input.surfaceProbes,
+    ...(input.hoverProbe ? { hoverProbe: input.hoverProbe } : {}),
+  };
+}
@@ -0,0 +1,154 @@
+import type { Viewport } from "@browser-skill/vom";
+import type { FrameDocument } from "../frame-document";
+import {
+  frameAxKey,
+  frameBackendKey,
+  type SemanticAxNode,
+  type SemanticFrame,
+  type SemanticGraph,
+  type SemanticGraphNode,
+  type SemanticNodeId,
+} from "./types";
+
+export interface BuildSemanticGraphInput {
+  documents: FrameDocument<SemanticAxNode>[];
+  viewport: Viewport;
+  rootFrameId?: string;
+  excludedBackendNodeIds?: ReadonlySet<number>;
+}
+
+function domNodeId(frameId: string, backendNodeId: number): SemanticNodeId {
+  return JSON.stringify([frameId, "dom", backendNodeId]);
+}
+
+function axNodeId(frameId: string, nodeId: string): SemanticNodeId {
+  return JSON.stringify([frameId, "ax", nodeId]);
+}
+
+export function buildSemanticGraph(input: BuildSemanticGraphInput): SemanticGraph {
+  const rootFrameId =
+    input.rootFrameId ??
+    input.documents.find((document) => !document.parentFrameId)?.frameId ??
+    input.documents[0]?.frameId ??
+    "root";
+  const frames = new Map<string, SemanticFrame>();
+  const nodes = new Map<SemanticNodeId, SemanticGraphNode>();
+  const nodeIdsByFrame = new Map<string, SemanticNodeId[]>();
+  const nodeByFrameBackend = new Map<string, SemanticNodeId>();
+  const nodeByFrameAx = new Map<string, SemanticNodeId>();
+
+  for (const [frameOrder, document] of input.documents.entries()) {
+    frames.set(document.frameId, {
+      frameId: document.frameId,
+      ...(document.parentFrameId ? { parentFrameId: document.parentFrameId } : {}),
+      ...(document.ownerBackendNodeId !== undefined
+        ? { ownerBackendNodeId: document.ownerBackendNodeId }
+        : {}),
+      contextScopeId: document.contextScopeId,
+      target: document.target,
+      ...(document.url ? { url: document.url } : {}),
+      order: frameOrder,
+    });
+
+    const frameNodeIds: SemanticNodeId[] = [];
+    nodeIdsByFrame.set(document.frameId, frameNodeIds);
+    for (const [index, dom] of document.domNodes.entries()) {
+      const id = domNodeId(document.frameId, dom.backendNodeId);
+      const node: SemanticGraphNode = {
+        id,
+        frameId: document.frameId,
+        backendNodeId: dom.backendNodeId,
+        dom,
+        sourceOrder: index,
+        excluded:
+          document.frameId === rootFrameId &&
+          input.excludedBackendNodeIds?.has(dom.backendNodeId) === true,
+      };
+      nodes.set(id, node);
+      frameNodeIds.push(id);
+      nodeByFrameBackend.set(frameBackendKey(document.frameId, dom.backendNodeId), id);
+    }
+
+    for (const [index, ax] of document.axNodes.entries()) {
+      const joinedId =
+        typeof ax.backendDOMNodeId === "number"
+          ? nodeByFrameBackend.get(frameBackendKey(document.frameId, ax.backendDOMNodeId))
+          : undefined;
+      const id = joinedId ?? axNodeId(document.frameId, ax.nodeId);
+      const existing = nodes.get(id);
+      if (existing) {
+        existing.ax = ax;
+        existing.axNodeId = ax.nodeId;
+      } else {
+        nodes.set(id, {
+          id,
+          frameId: document.frameId,
+          ...(typeof ax.backendDOMNodeId === "number"
+            ? { backendNodeId: ax.backendDOMNodeId }
+            : {}),
+          axNodeId: ax.nodeId,
+          ax,
+          sourceOrder: document.domNodes.length + index,
+          excluded:
+            document.frameId === rootFrameId &&
+            typeof ax.backendDOMNodeId === "number" &&
+            input.excludedBackendNodeIds?.has(ax.backendDOMNodeId) === true,
+        });
+        frameNodeIds.push(id);
+      }
+      nodeByFrameAx.set(frameAxKey(document.frameId, ax.nodeId), id);
+    }
+  }
+
+  for (const document of input.documents) {
+    for (const dom of document.domNodes) {
+      const id = nodeByFrameBackend.get(frameBackendKey(document.frameId, dom.backendNodeId));
+      const node = id ? nodes.get(id) : undefined;
+      if (!node || dom.parentBackendNodeId === null) continue;
+      node.domParentId = nodeByFrameBackend.get(
+        frameBackendKey(document.frameId, dom.parentBackendNodeId),
+      );
+    }
+    for (const ax of document.axNodes) {
+      const id = nodeByFrameAx.get(frameAxKey(document.frameId, ax.nodeId));
+      const node = id ? nodes.get(id) : undefined;
+      if (!node || !ax.parentId) continue;
+      node.axParentId = nodeByFrameAx.get(frameAxKey(document.frameId, ax.parentId));
+    }
+  }
+
+  const axChildren = new Map<SemanticNodeId, SemanticNodeId[]>();
+  const excludedQueue: SemanticNodeId[] = [];
+  for (const node of nodes.values()) {
+    if (node.axParentId) {
+      const children = axChildren.get(node.axParentId) ?? [];
+      children.push(node.id);
+      axChildren.set(node.axParentId, children);
+    }
+    if (node.excluded) excludedQueue.push(node.id);
+  }
+  for (let index = 0; index < excludedQueue.length; index += 1) {
+    for (const childId of axChildren.get(excludedQueue[index]) ?? []) {
+      const child = nodes.get(childId);
+      if (!child || child.excluded) continue;
+      child.excluded = true;
+      excludedQueue.push(childId);
+    }
+  }
+
+  for (const frame of frames.values()) {
+    if (!frame.parentFrameId || frame.ownerBackendNodeId === undefined) continue;
+    frame.ownerNodeId = nodeByFrameBackend.get(
+      frameBackendKey(frame.parentFrameId, frame.ownerBackendNodeId),
+    );
+  }
+
+  return {
+    viewport: input.viewport,
+    rootFrameId,
+    frames,
+    nodes,
+    nodeIdsByFrame,
+    nodeByFrameBackend,
+  };
+}
@@ -0,0 +1,59 @@
+import type { Viewport, VomScene } from "@browser-skill/vom";
+import type { FrameDocument } from "../frame-document";
+import { buildSemanticGraph as buildGraph } from "./build";
+import { projectSemanticGraph as projectGraph } from "./project";
+import { resolveSemanticGraph as resolveGraph } from "./resolve";
+import { normalizeSemanticStructure as normalizeStructure } from "./structure";
+import type {
+  ResolvedSemanticGraph,
+  SemanticAxNode,
+  SemanticGraph,
+  StructuredSemanticGraph,
+} from "./types";
+
+export type { SemanticAxNode } from "./types";
+
+export interface SemanticVomInput {
+  documents: FrameDocument<SemanticAxNode>[];
+  viewport: Viewport;
+  rootFrameId?: string;
+  excludedBackendNodeIds?: ReadonlySet<number>;
+}
+
+export function buildSemanticGraph(input: SemanticVomInput): SemanticGraph {
+  return buildGraph(input);
+}
+
+export function resolveSemanticGraph(
+  graph: SemanticGraph,
+  options: {
+    supplementalNames?: ReadonlyMap<string, string>;
+    identifierFallback?: boolean;
+  } = {},
+): ResolvedSemanticGraph {
+  return resolveGraph(graph, options);
+}
+
+export function normalizeSemanticStructure(graph: ResolvedSemanticGraph): StructuredSemanticGraph {
+  return normalizeStructure(graph);
+}
+
+export function projectSemanticGraph(graph: StructuredSemanticGraph): VomScene {
+  return projectGraph(graph);
+}
+
+export function buildSemanticVomScene(
+  input: SemanticVomInput & {
+    supplementalNames?: ReadonlyMap<string, string>;
+    identifierFallback?: boolean;
+  },
+): VomScene {
+  return projectSemanticGraph(
+    normalizeSemanticStructure(
+      resolveSemanticGraph(buildSemanticGraph(input), {
+        supplementalNames: input.supplementalNames,
+        identifierFallback: input.identifierFallback,
+      }),
+    ),
+  );
+}
@@ -0,0 +1,34 @@
+const IDENTIFIER_ATTRS = ["data-testid", "data-test-id", "id"] as const;
+const GENERIC_TOKENS = new Set(["btn", "button", "control", "icon", "item", "test", "tool"]);
+const GENERATED_PREFIXES = new Set(["ember", "headlessui", "mui", "radix", "react", "rc"]);
+
+function identifierTokens(value: string): string[] {
+  return value
+    .replace(/([a-z0-9])([A-Z])/g, "$1 $2")
+    .split(/[^a-zA-Z0-9]+/)
+    .map((token) => token.toLowerCase())
+    .filter(Boolean);
+}
+
+function readableIdentifier(value: string | undefined): string | undefined {
+  const raw = value?.trim();
+  if (!raw || raw.length < 3 || raw.length > 80) return undefined;
+  if (/^[a-f0-9]{8,}$/i.test(raw)) return undefined;
+
+  const tokens = identifierTokens(raw);
+  if (GENERATED_PREFIXES.has(tokens[0])) return undefined;
+  while (tokens.length > 1 && GENERIC_TOKENS.has(tokens[0])) tokens.shift();
+  while (tokens.length > 1 && GENERIC_TOKENS.has(tokens[tokens.length - 1])) tokens.pop();
+  if (tokens.length === 0 || !tokens.some((token) => /[a-z]{3,}/.test(token))) return undefined;
+  return tokens
+    .map((token, index) => (index === 0 ? `${token[0].toUpperCase()}${token.slice(1)}` : token))
+    .join(" ");
+}
+
+export function stableIdentifierName(attrs: Readonly<Record<string, string>>): string | undefined {
+  for (const name of IDENTIFIER_ATTRS) {
+    const label = readableIdentifier(attrs[name]);
+    if (label) return label;
+  }
+  return undefined;
+}
@@ -0,0 +1,85 @@
+import type { VomNode, VomScene } from "@browser-skill/vom";
+import type { SemanticNodeId, StructuredSemanticGraph, StructuredSemanticNode } from "./types";
+
+function retained(node: StructuredSemanticNode): boolean {
+  return node.structure.kind === "keep" || node.structure.kind === "inferred-group";
+}
+
+function connectedFrameIds(graph: StructuredSemanticGraph): Set<string> {
+  const connected = new Set<string>([graph.rootFrameId]);
+  const childrenByParent = new Map<string, string[]>();
+  for (const frame of graph.frames.values()) {
+    if (!frame.parentFrameId) continue;
+    const children = childrenByParent.get(frame.parentFrameId) ?? [];
+    children.push(frame.frameId);
+    childrenByParent.set(frame.parentFrameId, children);
+  }
+  const queue = [graph.rootFrameId];
+  for (let index = 0; index < queue.length; index += 1) {
+    for (const frameId of childrenByParent.get(queue[index]) ?? []) {
+      if (connected.has(frameId)) continue;
+      const frame = graph.frames.get(frameId);
+      if (!frame?.ownerNodeId) continue;
+      const owner = graph.nodes.get(frame.ownerNodeId);
+      if (!owner || !retained(owner)) continue;
+      connected.add(frame.frameId);
+      queue.push(frame.frameId);
+    }
+  }
+  return connected;
+}
+
+function domAncestors(
+  graph: StructuredSemanticGraph,
+  node: StructuredSemanticNode,
+  numericId: ReadonlyMap<SemanticNodeId, number>,
+): number[] {
+  const ancestors: number[] = [];
+  const seen = new Set<SemanticNodeId>();
+  let current = node.domParentId;
+  while (current && !seen.has(current)) {
+    seen.add(current);
+    const id = numericId.get(current);
+    if (id !== undefined) ancestors.push(id);
+    current = graph.nodes.get(current)?.domParentId;
+  }
+  return ancestors;
+}
+
+export function projectSemanticGraph(graph: StructuredSemanticGraph): VomScene {
+  const connectedFrames = connectedFrameIds(graph);
+  const orderedNodes = [...graph.frames.values()]
+    .filter((frame) => connectedFrames.has(frame.frameId))
+    .sort((a, b) => a.order - b.order)
+    .flatMap((frame) =>
+      (graph.nodeIdsByFrame.get(frame.frameId) ?? [])
+        .map((id) => graph.nodes.get(id))
+        .filter((node): node is StructuredSemanticNode => node !== undefined && retained(node))
+        .sort((a, b) => a.sourceOrder - b.sourceOrder),
+    );
+
+  const numericId = new Map<SemanticNodeId, number>();
+  orderedNodes.forEach((node, index) => numericId.set(node.id, index + 1));
+  const nodes: VomNode[] = orderedNodes.map((node) => ({
+    ...node.vom,
+    id: numericId.get(node.id) as number,
+    parentId: node.semanticParentId ? (numericId.get(node.semanticParentId) ?? null) : null,
+    ...(node.backendNodeId !== undefined ? { backendNodeId: node.backendNodeId } : {}),
+    frameId: node.frameId,
+    contextScopeId: graph.frames.get(node.frameId)?.contextScopeId ?? node.frameId,
+    referenceable: node.referenceable,
+    ...(node.dom
+      ? {
+          domParentId:
+            node.domParentId === undefined ? null : (numericId.get(node.domParentId) ?? null),
+          domAncestorIds: domAncestors(graph, node, numericId),
+        }
+      : {}),
+  }));
+
+  return {
+    viewport: graph.viewport,
+    nodes,
+    rootFrameId: graph.rootFrameId,
+  };
+}
--- a/Show More
+++ b/Show More