pyfbsdk_gen_doc.py is missing from MotionBuilders 2014 instalation. It provides contextual help in MotionBuilders Python editor and allows for pyfbsdk code introspection/completion with external IDE’s – like Wing or my personal favorite PyCharm. Autodesk were kind enough to provide it and to let me re-distrubute it
I had some trouble uploading a .py/.txt file – so I just pasted the whole thing over at tech artists org:
http://tech-artists.org/forum/showthread.php?4466-MotionBuilder-2014-pyfbsdk_gen_doc-py-for-download