Ironfang Finance API problem type

`idempotency_conflict`

Idempotency conflict. HTTP 409.

What it means

The Idempotency-Key was already used by this organisation for a request with different content. The original operation is left untouched.

What to do

Send a new key for a new request. Reuse a key only to replay the identical request.

What the response carries

type: https://ironfang.uk/problems/idempotency_conflict, this page.
status: Always 409 for this code.
code: idempotency_conflict. Stable: branch on this, not on the wording of title or detail.
detail: What happened this time, safe to show to a person. It never carries invoice content.
request_id: The same value as the X-Ironfang-Request-ID header. Quote it to support.
retry_after_seconds: Never present for this code.
outcome: Absent. This code is not a statement about any document.

Problems follow RFC 9457 and are served as application/problem+json. A validation finding is never a Problem: an invalid invoice is a successful response that lists its findings. See every problem type, the Finance guide and the OpenAPI contract.