Add a stdio MCP

1. Open Configure → Add MCP

2. Set a name
3. In Command or MCP URL, paste the command (for example npx or a full binary path)
4. Add extra args one per line if needed
5. Put secrets as KEY=value lines under env — values go in the OS keychain
6. Click Test, then Save

Sumeru starts the process with argv only (no shell). PATH and HOME are passed through; other env vars must be listed explicitly.