Fabrica MCP Stdio Bridge Server

What is Fabrica MCP Stdio Bridge Server?

A bridge for clients like Claude Desktop, Cursor, and Windsurf that do not yet support the new MCP HTTP Streamable transport used by the Fabrica gateway. It starts a shim MCP server using stdio transport on the local host and proxies requests to Fabrica's gateway over HTTP.

How to use Fabrica MCP Stdio Bridge Server?

First obtain your unique Toolbox ID (utbid) from Fabrica’s gateway UI. Then run the installation command for your client (Claude, Cursor, or Windsurf): npx -y @fabrica.work/cli@latest cli install <client> <utbid>. For VSCode, manually configure the server using the command npx -y @fabrica.work/cli@latest server <utbid>. Restart the desktop app after installation.

Key features of Fabrica MCP Stdio Bridge Server

• Bridges stdio MCP clients to Fabrica’s HTTP Streamable transport
• One-command installation for Claude, Cursor, and Windsurf
• Runs a shim MCP server on localhost
• Requires a unique Toolbox ID (utbid) from Fabrica
• Supports local development via FABRICA_GATEWAY_URL environment variable
• Compatible with the MCP inspector for testing

Use cases of Fabrica MCP Stdio Bridge Server

• Use Fabrica tools from Claude Desktop, which only supports stdio transport
• Access the Fabrica gateway from Cursor or Windsurf
• Integrate Fabrica MCP functionality into VSCode
• Develop and test the bridge locally against a local gateway

FAQ from Fabrica MCP Stdio Bridge Server

How do I get a unique Toolbox ID (utbid)?

Obtain your utbid from Fabrica’s gateway UI. It is required for all installation commands.

How do I install for Claude?

Run npx -y @fabrica.work/cli@latest cli install claude <utbid> in a terminal. This adds an entry to Claude’s MCP config at ~/Library/Application Support/Claude/claude_desktop_config.json. Restart Claude Desktop after installation.

How do I install for VSCode?

Follow the VSCode MCP server setup instructions. Use the command npx -y @fabrica.work/cli@latest server <utbid> as the server command. If configured globally, the settings are in ~/Library/Application Support/Code/User/settings.json.

How do I use a local gateway during development?

Set the FABRICA_GATEWAY_URL environment variable to a local URL (e.g., http://localhost:3000/api/mcp) before starting the server.

Where can I find logs for troubleshooting?

For Claude, logs are under /Users/<username>/Library/Logs/Claude. For Cursor and Windsurf, log locations are not yet documented. General debugging guidance is available at https://modelcontextprotocol.io/docs/tools/debugging.