{
  "name": "sessions_send_message",
  "description": "Send a chat message to an existing session and wait for the reply (non-streaming).",
  "input_schema": {
    "type": "object",
    "properties": {
      "sessionId": {
        "type": "string"
      },
      "message": {
        "type": "string"
      },
      "attachments": {
        "type": "array",
        "items": {
          "type": "object"
        }
      }
    },
    "required": [
      "sessionId",
      "message"
    ]
  },
  "timeout": 180
}