browser-mcp-cdp

browser-mcp-cdp

A Model Context Protocol (MCP) server that drives your real local Chrome via the Chrome DevTools Protocol. Designed for agents that need access to your logged-in sessions (Gmail, internal dashboards, banking, etc.) without uploading credentials to a cloud service.

Why another browser MCP?

Different tradeoffs from the alternatives:

	browser-mcp-cdp	Playwright MCP	Chrome DevTools MCP
Browser	Your local Chrome	Managed Playwright Chromium	Your local Chrome
Login state	✅ Snapshot of your profile (cookies, logins, IndexedDB)	❌ Fresh profile	✅ Real profile (modifies it)
Profile isolation	✅ Copy-on-start, real profile untouched	N/A	⚠️ Direct attach
Multi-client	✅ Shared broker across MCP clients	❌ Per-client	❌ Per-client
Dependencies	Node only (no Playwright download)	Playwright + browsers	Node only

The profile snapshot pattern means you can ask an agent to "check my email" — it sees your Gmail logged in — but the agent's actions never modify your real Chrome profile. Each session gets a disposable copy.

Install

claude mcp add browser -- npx -y browser-mcp-cdp

Or add manually to ~/.claude.json / Claude Desktop config:

{
  "mcpServers": {
    "browser": {
      "command": "npx",
      "args": ["-y", "browser-mcp-cdp"]
    }
  }
}

Requires Node 18+ and Google Chrome installed.

Tools

Tool	Purpose
browser_navigate	Load a URL, return final URL + title
browser_evaluate	Run JS in the page, return result
browser_screenshot	PNG of current page
browser_click	Click via CSS selector
browser_click_at	Click at pixel coordinates (pierces iframes / overlays)
browser_fill	Set value on input/textarea/select
browser_wait_for	Wait for a selector to appear
browser_get_url	Current URL
browser_get_text	Visible text of page or element
browser_get_html	outerHTML of page or element
browser_scroll	Scroll by (x, y) pixels
browser_tabs	List open tabs
browser_new_tab	Open a new tab

Environment variables

Var	Default
BROWSER_MCP_CHROME_PATH	Auto-detected per OS
BROWSER_MCP_CHROME_PROFILE_ROOT	OS-standard Chrome profile dir
BROWSER_MCP_BROKER_SOCKET_PATH	~/.browser-mcp/broker.sock
BROWSER_MCP_BROKER_LOCK_PATH	~/.browser-mcp/broker.lock
BROWSER_MCP_BROKER_IDLE_TIMEOUT_MS	600000 (10 min)

How it works

• First MCP client connection spawns a broker subprocess (detached).
• Broker copies your Chrome profile's cookies/local storage/login data to a temp dir.
• Broker launches Chrome with --user-data-dir=<temp> and --remote-debugging-port.
• Subsequent MCP clients connect to the same broker over a Unix socket → they share one Chrome.
• Broker exits after BROKER_IDLE_TIMEOUT_MS of no activity; temp profile is deleted.

Security

This server lets an LLM execute arbitrary JavaScript in a browser that is logged into your accounts. Only use with models and prompts you trust. Profile snapshotting limits damage (no persistent mutations to your real Chrome), but the agent can read cookies, session tokens, and any data visible to logged-in you for the duration of the session.

License

MIT