Compared with web-automation servers, this trades capability for something you can point at your personal browser: no page modification, no arbitrary scripting, consent per domain before content is read, and screenshot permission that Firefox itself enforces and expires. The connection is local-only with a shared secret, and there are no runtime third-party dependencies in the extension. The project still calls itself experimental.
An MCP server paired with a Firefox extension, giving read access to tabs, history and page text, plus tab management.
- Open and close tabs, and get the list of what is open
- Tab groups created with a name and colour, and tabs reordered
- Browser history read and searched
- A webpage's text content and links, with user consent
- Find and highlight text in a tab, with user consent
- A screenshot of a tab's visible area, authorised per tab
- An audit log in the extension for tool calls, and per-tool enable and disable
Firefox with the add-on from addons.mozilla.org, and either the Claude Desktop extension file or a local MCP server run with node. Set EXTENSION_SECRET to the value on the extension's preferences page; EXTENSION_PORT defaults to 8089. A Docker configuration is also provided. Reading page content requires your consent per domain, enforced at the extension manifest level; screenshots require clicking the toolbar button for that tab, and the authorisation expires when the tab navigates or closes.