From HTTP MCP to stdio: Lessons Connecting an AI Agent to a Desktop IDE

The obvious way to connect an AI Agent to a running IntelliJ is an HTTP MCP server inside the IDE. I built it, shipped it, and used it daily — and it kept breaking on real workstations: dynamic ports, start-order lottery, multiple IDEs, and the agent-up/IDE-down dead end. Here is why I moved the whole thing to stdio and a CLI coordinator called devrig, and what the journey taught me.