# Implementing C++ CFX Tags

CFX tags built in C++ use the tag request object, represented by the C++ class CCFXRequest. This object represents a request made from an application page to a custom tag. A pointer to an instance of a request object is passed to the main procedure of a custom tag. The methods available from the request object allow the custom tag to accomplish its work. See the "C++ CFX Reference" for a detailed description of the CFXAPI classes and members.