Idempotency
Send an `Idempotency-Key` header on every create. Without one, a network timeout followed by the retry your HTTP client makes on its own produces a second post.
How it works
Idempotency-KeyHeader
Idempotency-Key: 7c9e6679-7425-40de-944b-e07fc1f90ae7The key is remembered for 24 hours, scoped to your account and to the exact request body.
What a repeat gets back
- Same key, same body, already finished — the original response is returned again and nothing new is created.
- Same key while the first request is still running —
409. Retry in a moment. - Same key, different body —
422. Returning the first answer for a second request would be worse than refusing.
Only a completed create is remembered. A request rejected by validation is not, so fixing the body and sending it again under the same key works.