{
  "plain_message": {
    "type": "plain",
    "text": "Hello, this is a test message."
  },
  "image_message": {
    "type": "image",
    "url": "https://example.com/test.jpg",
    "file": null
  },
  "at_message": {
    "type": "at",
    "user_id": "12345",
    "nickname": "TestUser"
  },
  "reply_message": {
    "type": "reply",
    "id": "msg_123",
    "sender_nickname": "OriginalSender",
    "message_str": "This is the original message"
  },
  "file_message": {
    "type": "file",
    "name": "test.pdf",
    "url": "https://example.com/test.pdf"
  },
  "combined_message": {
    "components": [
      {"type": "at", "user_id": "bot_id"},
      {"type": "plain", "text": " Hello bot!"}
    ]
  }
}