{
  "artifact": {
    "description": "Async event emission protocol. Participants publish lifecycle events (requested/progress/completed/failed) to NATS subjects. Subject prefix is injected via cabling to avoid cross-Mode collisions.",
    "id": "event-emission",
    "layers": [
      {
        "description": "contract.ncl — EventEnvelope schema + EventEmissionInputs (subject_prefix requirement)",
        "media_type": "application/vnd.ontoref.domain.contract.v1",
        "required": true
      }
    ],
    "media_type": "application/vnd.ontoref.domain.v1",
    "uses_registry": "primary",
    "version": "0.1.0"
  }
}