HTTP 413
payload_too_largeMCP request body too large
The MCP request body exceeds the accepted transport limit.
Resolution
Reduce the request size and retry.
Response handling
Keep the response's request_id for diagnostics. Retry only transient 429 and 503 responses, using the rate-limit headers and exponential backoff with jitter. Correct 400, 401, and 403 requests before retrying.