This is for the specific hell of when your browser loads fine but Cursor or VS Code's AI features won't connect. It checks five layers on macOS: system proxy settings via networksetup, stale localhost ports from closed VPN apps, lingering launchctl environment variables, editor configs in settings.json, and whether proxy ports actually have something listening. The MCP server exposes diagnose_proxy, list_fixes, and supported_editors tools that return structured JSON with root cause analysis and executable networksetup commands. Built for the common case where a proxy was disabled but left 127.0.0.1:10903 configured somewhere, breaking streaming connections that AI completions depend on.
claude mcp add --transport stdio jiansen-proxy-doctor -- uvx proxy-doctor