{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://yovision.local/contracts/events/v1/problem.schema.json",
  "title": "YoVision contract problem v1",
  "type": "object",
  "additionalProperties": false,
  "required": ["code", "message"],
  "properties": {
    "code": {"enum": ["invalid_event", "unsupported_schema_version", "idempotency_conflict", "evidence_not_found", "evidence_expired"]},
    "message": {"type": "string", "minLength": 1, "maxLength": 512},
    "field": {"type": "string", "pattern": "^[A-Za-z0-9_.\\[\\]-]{1,128}$"},
    "existing_event_id": {"type": "string", "pattern": "^[A-Za-z0-9][A-Za-z0-9._:-]{0,127}$"}
  }
}