Required for mutating calls
Idempotency
Mutating API calls use stable Idempotency-Key headers. Replaying the same key with the same auth context and identical request body returns the original response where replay is supported. Reusing the same key with a changed payload, source hash, or auth/scope context returns a structured 409 conflict, normally idempotency_key_conflict or a resource-specific payload conflict. Generate keys per source action, such as erp:invoice:create:<source-id> or erp:payment:record:<source-id>.
Replay contract
POSTStable key example
Idempotency-Key: erp:invoice:create:invoice-2026-0001Same key, same body, same auth context replays. Same key with changed payload returns a structured 409 conflict.
Related API reference
Use the endpoint reference pages for request schemas, response bodies, status codes, and examples generated from the live OpenAPI contract.