For both C++ and Python, one can build a custom application using the CanvasWindow and Inspector, or displaying a data representation with the HippoDraw Qt widget, QtViewWidget or both in the same application. When using the Qt widget, displaying the Inspector is optional and not all the Inspector controls are available.
Building custom applications with C++ and Application building with Python extension module give some examples of usage.
If your custom application uses Doxygen for its documentation, you can use the hippodraw tag file and an entry in your Doxygen configuration file such as
TAGFILES = hippodraw.tag=http://www.slac.stanford.edu/grp/ek/hippodraw/