The JetBrains MCP Proxy Server is a Node.js application that acts as a middleware between MCP-compatible clients (such as Claude Desktop or VS Code) and JetBrains IDEs equipped with the MCP Server plugin. It discovers the IDE's MCP endpoint by scanning a predefined port range (63342-63352) or using a specified IDE_PORT environment variable, caches the endpoint, and periodically verifies its availability. The proxy then exposes an MCP server over stdio, forwarding tool listing and tool invocation requests to the IDE's HTTP-based MCP endpoint. The implementation uses the Model Context Protocol SDK for stdio communication and node-fetch for HTTP requests, featuring error handling, logging, and endpoint caching with periodic refresh.