{
  "kind": "callback_request",
  "expect": "invalid",
  "expect_error": "empty sentinel string in field `request.invocation_id`",
  "description": "empty sentinel string for invocation_id must be rejected",
  "data": {
    "schema_version": "lifeloop.v0.2",
    "event": "session.starting",
    "event_id": "evt-1",
    "adapter_id": "codex",
    "adapter_version": "0.1.0",
    "integration_mode": "native_hook",
    "invocation_id": ""
  }
}
