Privacy policy

Last updated: 2026-10-10

MCP Browser Extension is an open-source tool (MIT, https://github.com/Mehmoodqureshi/chrome-mcp) that lets an AI agent running on your own computer drive the Chrome you already use.

What the extension does

It opens a WebSocket connection to the MCP Browser Extension server (npm package @mehmoodqureshi/chrome-mcp) running on the same machine, at 127.0.0.1 only, and carries out the commands that server sends: listing and opening tabs, navigating, clicking, typing, reading page text and HTML, taking screenshots, reading cookies and site storage, and saving downloads. The server is started by you, on your computer, from your MCP client (for example Claude Code or Claude Desktop).

What data it handles

• Page content, screenshots, cookies, and site storage of the tabs the server asks about. This data is sent only to the local server over the loopback interface. The server hands it to the AI client you configured.
• A pairing token and port, stored in the extension's local storage, so the server can tell this browser apart from any other local program.
• A random install id, created on first run and sent only to the local server, so it can tell two Chrome profiles apart and keep each one's name.
• The connection state, the profile name you chose or were given, and your "Outline the tabs" setting, also in local storage.
• The ids of the tabs it opened itself (numbers only, in session storage that Chrome clears when it closes), so it reuses only its own blank tabs and never one of yours.
• The list of sites the local server currently allows, and up to ten site names (host names only, such as example.com; never full addresses or page content) that the server recently refused, so the Options page can show them with an Allow button. They stay in local storage until you allow or dismiss them. When you click Allow or Remove, that host name is sent to the local server only.

One-click Connect

The Connect button uses Chrome's native messaging. The MCP Browser Extension server registers a small helper with your browsers each time it starts; when you click Connect (and allow the optional "communicate with cooperating native applications" permission), the extension asks that helper for the port and token from ~/.chrome-mcp/handshake.json and saves them like a manual pairing would. It all happens on your computer. Chrome allows only this extension to start the helper, and the helper answers nothing but the pairing.

What it does not do

• It never sends any data to the extension author or to any remote server. The only network endpoint it connects to is 127.0.0.1.
• It does not collect analytics, telemetry, or crash reports.
• It does not run remote code. All code is in the package you install.
• It does nothing until you pair it with a local server, and it acts only on the domains that server's allowlist permits. The server ships deny-all by default.

Which sites it can touch

Access is decided by the allowlist of the local server: the sites given with --allow-domain, plus any you allow yourself on the extension's Options page. The extension requests access to all URLs only so that allowlist can name any site; without a matching entry, no command runs on a page. The AI agent cannot add a site: the extension refuses every command aimed at its own pages, so only you can click Allow.

Data retention

Nothing is retained by the extension beyond the local-storage items above. You can clear them by removing the extension. Anything the server saves (screenshots, downloads, action history, and the sites you allowed from the Options page, in allowed-sites.json) lives in ~/.chrome-mcp on your own machine under your control.

The MCP Browser Extension server (separate from the extension)

This policy covers the extension, which sends nothing anywhere. The MCP Browser Extension server, the npm package you run from your MCP client, makes two kinds of outside requests:

• Anonymous usage statistics, to PostHog: a random install id (not the extension's), its version, OS, CPU architecture, Node version, whether the session owns or shares the bridge port, how many browsers are paired, the paired extension's version and whether it is the store or an unpacked copy, and, when none is, which of a few fixed reasons applies (no_extension, token_mismatch, version_mismatch, profile_mismatch), counts of tool calls and error codes, and for each tool call its name and group, duration, whether it failed and the error code, the AI client's name and version (such as claude-code), the MCP protocol revision, the AI model name when the client includes it in its own request metadata, and a random session id. When a client connects, its name and version and the list of tool names offered. It never sends URLs, site names, page content, tool arguments, cookies, profile names or anything the extension reads. Events are personless and GeoIP lookup is disabled. Turn it off with CHROME_MCP_TELEMETRY=0, DO_NOT_TRACK=1, or --no-telemetry. Details: https://github.com/Mehmoodqureshi/chrome-mcp#telemetry
• An update check, to the npm registry (registry.npmjs.org), once at startup, asking only for the latest version number of @mehmoodqureshi/chrome-mcp. It carries no install id or usage data; npm sees what any package download shows it (your IP address). When a newer version exists, the server starts it through npx, which downloads it from npm. Turn it off with CHROME_MCP_AUTO_UPDATE=0 or --no-auto-update.

Contact

Open an issue at https://github.com/Mehmoodqureshi/chrome-mcp/issues.