JetBrains MCP Proxy Server

The server proxies requests from client to JetBrains IDE.

Install MCP Server plugin

https://plugins.jetbrains.com/plugin/26071-mcp-server

Usage with Claude Desktop

To use this with Claude Desktop, add the following to your claude_desktop_config.json. The full path on MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json, on Windows: %APPDATA%/Claude/claude_desktop_config.json.

{
  "mcpServers": {
    "jetbrains": {
      "command": "npx",
      "args": ["-y", "@jetbrains/mcp-proxy"]
    }
  }
}

Configuration

If you’re running multiple IDEs with MCP server and want to connect to the specific one, add to the MCP server configuration:

"env": {
  "IDE_PORT": "<port of IDE's built-in webserver>"
}

By default, we connect to IDE on 127.0.0.1 but you can specify a different address/host:

"env": {
  "HOST": "<host/address of IDE's built-in webserver>"
}

To enable logging add:

"env": {
  "LOG_ENABLED": "true"
}

Troubleshooting

Node.js Version Requirements

Problem: Error message: Cannot find module 'node:path'

Solution: MCP Proxy doesn’t work on Node 16. Upgrade your Node.js installation to version 18 or later. Make sure that command in config points to the correct Node.js version. Try to use the full path to the latest version of NodeJS.

MacOS: Plugin Unable to Detect Node.js Installed via nvm

Problem: On MacOS, if you have Node.js installed through nvm (Node Version Manager), the MCP Server Plugin might be unable to detect your Node.js installation.

Solution: Create a symbolic link in /usr/local/bin pointing to your nvm npx executable:

which npx &>/dev/null && sudo ln -sf "$(which npx)" /usr/local/bin/npx

This one-liner checks if npx exists in your path and creates the necessary symbolic link with proper permissions.

Using MCP with External Clients or Docker Containers (LibreChat, Cline, etc.)

Problem: When attempting to connect to the JetBrains MCP proxy from external clients, Docker containers, or third-party applications (like LibreChat), requests to endpoints such as http://host.docker.internal:6365/api/mcp/list_tools may return 404 errors or fail to connect. Solution: There are two key issues to address:

1. Enable External Connections:

In your JetBrains IDE, enable “Can accept external connections” in the Settings | Build, Execution, Deployment | Debugger.

2. Configure with LAN IP and Port:

Use your machine’s LAN IP address instead of host.docker.internal Explicitly set the IDE_PORT and HOST in your configuration Example configuration for LibreChat or similar external clients:

mcpServers:
  intellij:
    type: stdio
    command: sh
    args:
      - "-c"
      - "IDE_PORT=YOUR_IDEA_PORT HOST=YOUR_IDEA_LAN_IP npx -y @jetbrains/mcp-proxy"

Replace:

YOUR_IDEA_PORT with your IDE’s debug port (found in IDE settings) YOUR_IDEA_LAN_IP with your computer’s local network IP (e.g., 192.168.0.12)

How to build

1. Tested on macOS
2. brew install node pnpm
3. Run pnpm build to build the project