For the data structure of **ConfigInfo**, **ClientInfo**, **AlgorithmInfo**, and **DataInfo**, see [Table 2](sdk.md#table22154317482) in the SDK development guidelines.
The **Request** and **Response** classes define the requests and responses used for communication between the AI engine server and algorithm plug-ins. A request encapsulates the request content and input data of the caller. The plug-in returns the calculation result to the AI engine server through a response.
[Table 3](#table16273647125120) describes the attributes of the **Request** class.