The manpages should be written and built using reStructuredText and Sphinx.
See http://sphinx.pocoo.org/builders.html#sphinx.builders.manpage.ManualPageBuilder for details.
We should also have something like a manpage on docs.mopidy.com as it would be nice to have a place online that is easy to get to for looking up all the flags.
The Debian packages comes with manpages for all commands, generated by Sphinx, as of 0.16.1. The manpages are also available as a part of the docs: http://docs.mopidy.com/en/latest/commands/