This package defines a set of general-purpose messages and services for motion planning and control. It includes messages that can be used to specify joint paths, represent robot state and services to compute motion plans. It also includes a set of conversion methods that can be used to convert messages from one form to another.
The exposed C++ API for this package consists of a set of converter functions that can be used to transform between different messages and also provide a simple C++ interface to some of the services defined here. It can be found here.