Capmonster MCP Patchright Captcha Solver

capmonster-mcp-patchright

Stealth browser MCP server for AI agents — 66 tools, Patchright-powered, reduced CDP automation signals.

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Fork of mcp-patchright that adds a per-call world: "main" option to browser_evaluate / browser_run_code_unsafe, so page-defined window globals are visible and callable. Defaults to Patchright's isolated stealth world (matching upstream); opt into main only when a page's own script needs to see or be called by your evaluated code. Everything else matches upstream mcp-patchright.

Why Patchright, not Playwright?

See the full comparison for details.

Quick start

npm i -g capmonster-mcp-patchright
capmonster-mcp-patchright --port 9321 --host 127.0.0.1

With Claude / GPT / agents

{
  "mcpServers": {
    "patchright": {
      "command": "npx",
      "args": ["capmonster-mcp-patchright", "--port", "9321", "--host", "127.0.0.1"]
    }
  }
}

Features

• 66 MCP tools — full browser automation surface
• world: "main" opt-in — browser_evaluate / browser_run_code_unsafe can run in the page's real world to see/call page-defined globals (default stays isolated/stealth)
• browser_find — search the current aria snapshot for text/regex, cheaper than a full browser_snapshot
• browser_save_blob — save a Blob/data URL produced by page code to disk
• 3 transports — stdio, SSE, Streamable HTTP (/mcp)
• Persistent profiles — real Chrome profile, reuse across sessions
• Multi-page — tab management (new, list, switch, close)
• Owner-scoped HTTP sessions — isolate tabs per caller with owner query/header
• CDP attach — control an already-running Chrome
• Network tracking + interception — request list/detail, offline toggle, block/mock routes
• Session import/export — browser_storage_save / browser_storage_load (cookies + localStorage)
• Granular storage — per-key cookie / localStorage / sessionStorage CRUD (browser_cookie_*, browser_localstorage_*, browser_sessionstorage_*)
• Authenticated API requests — browser_api_request reuses session cookies (hybrid scraping)
• Text/HTML extraction — browser_get_visible_text / _html (token-light)
• Iframe-aware — pass frameSelector to any element tool (click/fill/type/hover/press/wait_for/select/drag) to act inside an iframe
• PDF export — browser_save_pdf via CDP (works in headed/stealth mode)
• Video recording — browser_start with recordVideo, browser_video_save; .webm flushed on browser_close
• Element highlight — browser_highlight / browser_hide_highlight overlays for screenshots & recordings
• Stealth profiles — proxy / geolocation / locale / timezone / colorScheme
• Console capture — real-time console message stream

Tools

Full comparison HTML in /docs/tool-comparison.html.

• browser_start
• browser_status
• browser_navigate
• browser_new_page
• browser_pages
• browser_switch_page
• browser_close_page
• browser_snapshot
• browser_find
• browser_take_screenshot
• browser_click
• browser_fill
• browser_type
• browser_hover
• browser_press_key
• browser_wait_for
• browser_evaluate
• browser_fingerprint_check
• browser_navigate_back
• browser_select_option
• browser_handle_dialog
• browser_file_upload
• browser_network_requests
• browser_network_request
• browser_console_messages
• browser_resize
• browser_drag
• browser_fill_form
• browser_run_code_unsafe
• browser_add_init_script
• browser_network_state_set
• browser_api_request
• browser_get_visible_text
• browser_get_visible_html
• browser_iframe_click
• browser_iframe_fill
• browser_route_block
• browser_route_mock
• browser_route_clear
• browser_storage_save
• browser_storage_load
• browser_cookie_list
• browser_cookie_get
• browser_cookie_set
• browser_cookie_delete
• browser_cookie_clear
• browser_localstorage_list
• browser_localstorage_get
• browser_localstorage_set
• browser_localstorage_delete

Development

Owner-scoped HTTP sessions

HTTP mode requires a stable owner on the MCP URL (?owner=<id>) or with the X-Browser-Owner header. Page listing, switching, navigation, and closing are restricted to that owner's tabs. Delete /owners?owner=<id> to close all tabs owned by one caller without stopping the browser or clearing the profile.

npm install
npm run build
node dist/index.js

Release

Install the matching Chromium build once, then prepare a release from the exact dependency versions in package-lock.json, run the full verification suite, and inspect the package without publishing it:

npx patchright install chromium
npm run release:check
npm publish

By default, browser_start launches Chromium via patchright as headed real Chrome with a persistent profile at:

~/.maestro/stealth-playwright-mcp/profiles/default

You can override it with the userDataDir tool argument or STEALTH_PLAYWRIGHT_USER_DATA_DIR.

To attach to an already-running Chrome instead of launching one, start Chrome with remote debugging and pass cdpEndpoint to browser_start:

google-chrome --remote-debugging-port=9222 --user-data-dir=$HOME/.maestro/stealth-playwright-mcp/profiles/cdp

{ "cdpEndpoint": "http://127.0.0.1:9222" }

browser_snapshot returns Playwright's AI aria snapshot. Use [ref=eN] values from that snapshot with browser_click, browser_fill, browser_type, browser_hover, browser_press, and browser_wait_for by passing { "ref": "eN" }. CSS selectors remain supported via { "selector": "..." }.

MCP config example:

{
  "mcpServers": {
    "patchright": {
      "command": "node",
      "args": ["/path/to/capmonster-mcp-patchright/dist/index.js"]
    }
  }
}

Direction

Shipped:

• ✅ persistent user data dirs
• ✅ CDP attach to real Chrome
• ✅ proxy / timezone / locale / geolocation profiles
• ✅ accessibility snapshots for LLM-friendly page control
• ✅ fingerprint diagnostics
• ✅ network interception (block / mock)
• ✅ session import/export (storageState)
• ✅ PDF export
• ✅ authenticated API requests (reuse browser cookies)
• ✅ lightweight text/HTML extraction
• ✅ iframe actions
• ✅ world: "main" opt-in for browser_evaluate / browser_run_code_unsafe
• ✅ aria-snapshot search (browser_find)
• ✅ save Blob/data URL output to disk (browser_save_blob)

Next:

• rebrowser-playwright backend
• codegen sessions
• coordinate-based (vision) clicks
• tracing / video recording

⚖️ Responsible use

Use this server only on websites you own or have permission to automate, and in line with the terms of service of those websites and applicable law. Patchright reduces common automation signals; acceptance of automated traffic by any site is not guaranteed.

📚 Related

• CapMonster Cloud MCP Server — the CAPTCHA-solving part of the workflow
• CapMonster Cloud MCP page
• CapMonster Cloud Documentation
• Model Context Protocol (MCP) Docs

📄 License

MIT