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412 Precondition Failed

The If-Match precondition did not hold.

Machine code: precondition_failed

The ETag you supplied in If-Match does not match the resource's current version — it changed since you last read it.

How to resolve

Re-fetch the resource to obtain its current ETag, then retry the write with the new value.

Response shape

Every error is an RFC 9457 application/problem+json document with a machine code and a trace_id you can quote to support.

{
  "type": "https://docs.openiris.io/errors/412",
  "title": "Precondition Failed",
  "status": 412,
  "code": "precondition_failed",
  "detail": "The supplied If-Match ETag is stale.",
  "instance": "/v1/resources/42",
  "trace_id": "0HMVABCDEF123"
}