{
  "message_id": "msg_20260513_0001",
  "created_at": "2026-05-13T00:00:00Z",
  "from": {
    "scheme": "email",
    "address": "person@example.com"
  },
  "to": {
    "scheme": "agent-endpoint",
    "address": "owner@example.net"
  },
  "channel": "email",
  "subject": "hello",
  "body": "Can you take a look at this?",
  "attachments": [],
  "declared_urgency": "normal",
  "metadata": {}
}