Cursor MCP Troubleshooting: Command Failed, Disconnects & Paths

Cursor is powerful with MCP, but GUI apps often fail where the terminal works. Use this checklist for the most common failures.

macOS GUI apps do not load your .zshrc PATH by default.

Error: command not found / spawn failed

Cursor may not see npx from nvm. Fix: use absolute paths to node/npx in the MCP config.

Error: server disconnects immediately

Usually stdout pollution (debug logs) or the process crashing on import.

• Remove console.log from server code.
• Run the same command in a terminal to see stderr.

Pass secrets via env in the MCP config—not hardcoded in args that get logged.

Error: missing API keys

Env vars in your shell are not inherited. Put them under env in the MCP server block.

Related

• Essential MCP servers
• Install MCP · Skills directory