Guides

Idempotency

Networks fail. If you send a POST and get no answer, you cannot know whether the job started. Send it again with the same Idempotency-Key and you are never charged twice.

HTTP

POST /api/v1/find-contacts
Idempotency-Key: 6f1c2a1e-3b0a-4c47-9c0e-1f2d3e4a5b6c

How it works

Every POST accepts an Idempotency-Key header: any unique string up to 255 characters. A new UUID per request is best.
The first request runs. Any retry with the same key and the same body in the next 24 hours gets the first answer back, with the header Idempotent-Replayed: true. No second job, no second charge.
The same key with a different body gets 422 idempotency_key_reused. Use a new key for a new request.
If the first request is still running, a retry gets 409 idempotency_in_progress. Wait a moment and retry.
Server errors (5xx) are not stored: a retry with the same key runs again.
Keys are per account and per key kind (test and live never mix).

Make, Zapier and n8n: set the header to a value that is the same on a re-run of the same step, for example the record id from the trigger.