The functionality offered by the MDL SDK API is split into so-called API components.
Each component gives access to some aspect of the MDL SDK API. The basic interface mi::neuraylib::INeuray gives access to these API components via its get_api_component()
methods.
This page here lists all API components. Note that some API components are always available (e.g., configuration interfaces), while other API components might only available while the MDL SDK is running.