opencode-chrome

Give your local opencode agent full control of a real browser — clicks, types, screenshots, all via real CDP Input events that bypass bot detection.

62 MCP tools · MV3 Chrome extension + Node.js bridge · chrome.debugger API for full CDP access

What it does

opencode-chrome is a Chrome/Edge extension that exposes 62 browser automation tools to any MCP-compatible agent (like opencode, Claude Code, etc.) over a localhost WebSocket. Every form interaction uses the CDP Input domain — real mouse and keyboard events at the browser level — so LinkedIn and other anti-bot sites can't detect automation.

Used in production to add 5/5 CI/CD skills to linkedin.com/in/anton-petnitsky and publish a v0.6.0 announcement post — both through CDP Input, not JS element.click().

Related MCP server: chrome-devtools-mcp

Architecture

┌─────────────────────┐       WS 127.0.0.1:8766       ┌──────────────────┐       stdio MCP       ┌──────────┐
│  Chrome Extension   │ ◄───────────────────────────► │  bridge.mjs      │ ◄──────────────────► │ opencode  │
│  (MV3, debugger API)│                                │  (Node.js)       │                      └──────────┘
└─────────────────────┘                                └──────────────────┘
        │
        │ CDP :9223
        ▼
   ┌──────────┐
   │  Edge    │
   └──────────┘

• Extension — MV3 service worker, uses chrome.debugger for full CDP (no need for --remote-debugging-port on default profile)

• Bridge — WS server (for the extension) + MCP stdio server (for the agent), token-authenticated

• Token — auto-generated on first run, stored in ~/.opencode-chrome/token (chmod 600)

Quick start

1. Start the bridge

node bridge/bridge.mjs
# [bridge] listening on ws://127.0.0.1:8766
# [bridge] token: a1b2c3d4...  (also saved to ~/.opencode-chrome/token)

2. Start Edge with the extension

"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe" \
  --user-data-dir=D:\Projects\opencode-chrome\.edge-profile \
  --profile-directory=Default \
  --remote-debugging-port=9223 \
  --load-extension=D:\Projects\opencode-chrome\extension \
  --no-first-run --no-default-browser-check \
  https://www.linkedin.com/in/anton-petnitsky/

(Edge is used because Chrome 151+ blocks CDP on default profile but Edge allows --load-extension. Use Chrome if you have a custom --user-data-dir.)

3. Auto-setup (recommended)

Instead of steps 1+2 manually, just run:

node scripts/auto.mjs

This script:

1. Starts the bridge if not running

2. Starts Edge with the extension

3. Auto-sets the extension token via CDP chrome.storage.sync.set

4. Waits for the extension to connect

5. Runs tabs_list to confirm everything works

4. Auto-recovery (optional)

For long-running sessions, run the watchdog in another terminal:

node scripts/watchdog.mjs

This monitors bridge (port 8766) and Edge (port 9223), auto-restarts them if they die.

62 MCP tools

All tools use CDP Input domain for mouse/keyboard (bypasses bot detection) and chrome.debugger for everything else.

Navigation (9)

chrome_tabs_list, chrome_tab_open, chrome_tab_navigate, chrome_tab_close, chrome_tab_switch, chrome_tab_wait_load, chrome_tab_back, chrome_tab_forward, chrome_tab_refresh

Mouse (7) — all real CDP Input events

chrome_click (selector), chrome_click_coords (x,y), chrome_hover, chrome_double_click, chrome_right_click, chrome_scroll, chrome_drag_and_drop

Keyboard (3) — real CDP Input

chrome_fill (selector + text), chrome_type (focused element), chrome_press_key (Enter, Tab, etc.)

Select (1)

chrome_select (dropdown by value or text)

Reading (6)

chrome_read (title + url + text), chrome_get_text, chrome_get_attribute, chrome_get_all_links, chrome_find_elements, chrome_eval (run JS)

Screenshots / PDF (4)

chrome_screenshot (image block), chrome_full_page_screenshot, chrome_element_screenshot, chrome_save_pdf

Extraction (4)

chrome_get_page_source, chrome_get_element_html, chrome_extract_table, chrome_get_computed_style

Waiting (2)

chrome_wait_for_element, chrome_wait_and_retry

Composite (2)

chrome_click_and_wait, chrome_fill_and_submit

Monitoring (1)

chrome_console

Advanced (5)

chrome_upload_file, chrome_iframe_list, chrome_iframe_eval, chrome_shadow_query, chrome_batch, chrome_if_exists

Cookies / Storage (4)

chrome_cookies_get, chrome_cookie_set, chrome_local_storage, chrome_export_session

Emulation (5)

chrome_set_viewport, chrome_set_user_agent, chrome_set_geolocation, chrome_set_timezone, chrome_emulate_network

v0.6.0 Anti-bot realism (4) — bypass LinkedIn et al.

chrome_click_in_shadow — pierces shadow DOM (artdeco-* web components) chrome_hover_and_reveal — hover + wait for hidden edit buttons chrome_human_type — realistic typing with jitter (50-150ms/char) and optional typo simulation chrome_scroll_to_element — smooth-scroll to target

Helper scripts

v0.6.0 changes

• Extension: 4 new anti-bot tools (click_in_shadow, hover_and_reveal, human_type, scroll_to_element)

• Bridge: was stuck at v0.1.0 (25 tools), now exposes all 62 tools via MCP. Added askExtensionWithRetry() for MV3 service worker lifecycle resilience

• Background SW: chrome.alarms keepalive every 24s, ping/pong every 20s, onStartup handler

• auto.mjs: full one-command setup

• post_linkedin.mjs: clipboard + sharebox helper

• verify_skills.mjs: profile skill checker

Why CDP Input (not JS .click())?

LinkedIn, Cloudflare, and most modern sites detect element.click() because:

• The event has isTrusted: false

• No real mouse trajectory

• Instant timing

chrome.debugger + Input.dispatchMouseEvent creates events with isTrusted: true — the browser itself dispatches them — which bypasses these checks. The extension only uses JS element.click() for reading (not visible to users) and never for form interaction.

Anti-bot features

LinkedIn's "About" section edit button is the only thing in this codebase that can't be automated. The button is rendered dynamically after a 2-3 second hover, only when the page detects a trusted mouse, and its click handler checks event.isTrusted. The v0.6.0 hover_and_reveal waits the right time, but LinkedIn's JS still blocks the synthetic click. This is a known limitation.

Workaround: copy-paste the text from D:\Documents\Desktop\linkedin_pending_cicd_2026-08-22.md into the About section manually (1-2 minutes).

MV3 service worker lifecycle

MV3 kills idle service workers after ~30 seconds. The extension uses chrome.alarms (every 24s) to keep itself alive, and the bridge's askExtensionWithRetry waits and retries when the SW reconnects. Expect occasional 2-3 second delays on long-running sessions.

License

MIT