curl --request POST \
  --url https://api.example.com/api/task/v1/{task_id}/message \
  --header 'Content-Type: application/json' \
  --data '
{
  "metadata": {},
  "parts": [
    {
      "metadata": {},
      "text": "<string>",
      "type": "text-part"
    }
  ],
  "reference_task_ids": [
    "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  ],
  "role": "user"
}
'

{
  "message": {
    "created_at": "2023-11-07T05:31:56Z",
    "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "metadata": {},
    "parts": [
      {
        "metadata": {},
        "text": "<string>",
        "type": "text-part"
      }
    ],
    "reference_task_ids": [
      "3c90c3cc-0d44-4b50-8888-8dd25736052a"
    ],
    "role": "user",
    "task_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  },
  "timeline_item": {
    "created_at": "2023-11-07T05:31:56Z",
    "event_payload": {
      "status": "submitted",
      "type": "task-status-update",
      "status_message_id": "<unknown>"
    },
    "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "task_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  }
}