Glossary · Published 2026-09-29 · AgentiSend team
Idempotency key
Idempotency key: The caller-chosen key that makes a retry of the same request return the first result.
Send Idempotency-Key on a mutating call. A retry with the same key and the same body returns the first result and does not send again. The key is kept for 7 days. Derive it from the thing being done, not from the clock.
The same key with a different body is idempotency_payload_mismatch. The fix field says to reuse the body or to send a new key. A new send needs a new key.
Related terms
- Fix field — The sentence on every refusal that says what to do next and which call does it.
- retry_after_seconds — The wait, in seconds, on a refusal that waiting can cure. Absent when waiting cannot.