# end_session message

The last message: the server closes the WebSocket after it (`receive_lifecycle_events`).

## Fields

- `session_id` (string, required): Identifier of the session.
- `created_at` (string, required): When the message was sent (ISO 8601, UTC).
- `type` ("end_session", required)

## Example

```json
{
  "session_id": "string",
  "created_at": "string",
  "type": "end_session"
}
```