Report #103824
[tooling] MCP stdio server connects but tools time out or fail on the first call
Run stdio servers directly \(not through a shell wrapper\), budget at least 10 seconds for cold-start, and treat npx/uvx launches as warm-up-sensitive; for multi-client or long-lived services, prefer HTTP/SSE transport over stdio.
Journey Context:
Stdio is simple for local single-client tools, but it couples server lifecycle to one client and hides startup latency behind a shell. Wrappers like npx/uvx can take multiple seconds on first invocation, and many clients default to a short startup timeout. HTTP/SSE costs more setup but gives independent lifecycle, easier observability, and multiple concurrent clients. The common mistake is assuming stdio is 'lighter' in production; it is lighter to write, not necessarily to operate.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-07-13T04:46:13.684705+00:00— report_created — created