MCP Browser

What MCP Browser MCP server does

MCP Browser MCP server connects MCP-compatible AI clients to a native macOS browser built around WKWebView. The browser has tabs, bookmarks, history, downloads, URL navigation, and normal browser controls, while the MCP interface lets an agent operate the active browser window.

Agents can open URLs, move backward or forward, reload pages, inspect the current URL and title, and create or switch tabs. DOM operations include clicking, filling fields, submitting forms, hovering, sending key presses, typing text, scrolling, finding text, retrieving elements, and reading the accessibility tree. The catalog also includes page reading, metadata, screenshots, PDF export, HTML rendering, JavaScript evaluation, links, forms, cookies, storage, and session clearing.

Additional tools expose bookmarks, console output, network activity, dialogs, downloads, uploads, waits, emulation, and window resizing. Downloads, uploads, and dialog interactions require user permission.

How it works

The application hosts the MCP service in-process and communicates over local HTTP. JSON-RPC requests use POST /mcp; GET /mcp provides an SSE-style status response. The default listener uses port 8833 and binds to 127.0.0.1, though the port can be configured.

Each launch uses a bearer token. Clients must send that token with requests, and the server rejects requests whose Host header is not 127.0.0.1 or localhost. The application records tool calls with their arguments, result summaries, and timing in an action log. Requests are routed to the active tab in the most recently focused window.

The browser keeps cookies, bookmarks, history, downloads, and other supported state on the Mac. The project states that it does not include an LLM provider or send data to the cloud on its own; network activity can still occur when an invoked browser action accesses a website.

Setup and configuration

The downloadable application requires macOS 14 or later and is distributed as a signed, notarised DMG for Apple Silicon. Install it in Applications, launch it, then open Settings → Connection to copy the endpoint and bearer token. Add the HTTP connection to an MCP client using the endpoint and an Authorization: Bearer <token> header.

The MCP Browser MCP server includes an MCP Clients settings tab that can patch configuration files for clients it supports, including Claude Desktop and Codex. Regenerating the token revokes the previous credential, so clients must be updated afterward.

Developers can build from source with Xcode 16 or later by opening the project, selecting the MCP Browser scheme, and building for My Mac. A command-line xcodebuild path is also documented. Forks require their own development team and bundle identifier.

Tools and capabilities

• Navigate, reload, inspect page state, and manage browser tabs.
• Interact with page controls and query DOM or accessibility information.
• Read page content, render HTML, capture screenshots, export PDFs, or evaluate JavaScript.
• Inspect cookies, storage, console logs, network logs, dialogs, links, and forms.
• Use bookmarks, downloads, uploads, waits, emulation, and resizing.
• Review agent activity in the local action log.

Limitations and notes

The MCP Browser MCP server is Mac-only and has no iOS build. Multi-window support exists, but MCP requests are routed only to the most recently focused window. The action log cannot yet be searched retroactively from the UI.

Site OAuth and basic-auth flows are handled by WebKit; the application does not store passwords itself. The project is intentionally unsandboxed so it can update MCP client configuration files and open external schemes when explicitly requested. Its server remains loopback-only and requires the bearer token.