Browser Session MCP

Browser Session MCP lets an AI agent drive the browser session you already have open — including pages you are logged into — through a Model Context Protocol (MCP) server running on your own machine.

This extension is the browser side of that loop. It exposes 11 automation tools to the local server over native messaging, and falls back to a loopback WebSocket (ws://127.0.0.1:9777) when the native host is not installed:

navigate, snapshot, click, type, press_key, evaluate, screenshot, scroll, tabs_list, tab_select, wait

• Works with your existing login state. Nothing is sent anywhere: the extension talks only to the local server you run.
• No remote code. Everything runs from the packaged files.
• Screenshots are written to disk by your local server, never uploaded.
• Typing goes through the browser's own editing pipeline, so pages receive a trusted InputEvent.
• Optional human-like cursor animation, and an opt-in force click for client-side disabled gates.

This add-on ships without its server. Install the open-source Browser Session MCP server (Node.js 22+) from the project repository, then click the toolbar icon and press Connect. Without that server the extension deliberately does nothing: it has no remote endpoint to talk to.

• tabs and <all_urls>: the agent needs to act on whichever page you ask it to work on.
• scripting: one self-contained function is injected per action; there are no persistent content scripts.
• nativeMessaging: preferred transport to the local server.
• storage: remembers your port and connect state.
• alarms: keeps the connection healthy.

Source code, issue tracker and the companion server live at https://github.com/ashu0729will/browser-mcp-lab