{
  "_comment_negative_example": "uses snake_case 'event_type' (drift Ricardo flagged on 2026-06-01) instead of canonical 'eventType'. Validator MUST reject because the schema requires 'eventType' and unevaluatedProperties=false (R10).",
  "event_type":  "case.coded",
  "occurredAt":  "2026-06-01T19:42:11Z",
  "sessionId":   "0f9ea092-c774-4624-bb10-8910ec03d1db",
  "instanceId":  "his-eoc-2026-06-01-12345",
  "format":      "spiges",
  "data":        "<spiges/>"
}