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422 Unprocessable Content

`missing_idempotency_key` — Idempotency-Key header missing

Message “Idempotency-Key header is required.”

What causes it

`POST /workflows/{id}/trigger`, `POST /workflows/{id}/batches`, or `POST /executions/{id}/re_evaluations` was sent without an `Idempotency-Key` header, or with an empty one.

How to fix it

Send a unique string per logical request, up to 200 characters; a UUID v4 is the convention. Keep it stable across retries of the same request.

Operations that return it

POST /workflows/{id}/trigger Trigger a workflow
POST /workflows/{id}/batches Create a batch from N rows
POST /executions/{id}/re_evaluations Re-evaluate an execution

Example response

HTTP/1.1 422 Unprocessable Content · Content-Type: application/json

422 Unprocessable Content

{
  "error": {
    "code": "missing_idempotency_key",
    "message": "Idempotency-Key header is required.",
    "details": [],
    "request_id": "6f1c2a3e-8d4b-4c5e-9f0a-1b2c3d4e5f60",
    "doc_url": "https://cascades.crscreditapi.com/docs/api/errors/missing_idempotency_key"
  }
}

Concepts › Idempotency