Idempotency

Retry chat requests safely with requestId.

POST /agents/{agentId}/chat accepts an optional UUID requestId.

{
  "message": "How do I reset my password?",
  "requestId": "9d2c8360-7321-42ae-a64c-c11053336f73"
}

Reuse the same requestId only for an exact retry of the same chat input. Reusing it with different input returns 409 request_id_conflict.

Generate the UUID before the first request and persist it until the request succeeds or fails permanently.