I've searched all available documentation and I can't find a good summary of
the nomenclature for chord symbols, beyond simple maj, min, 7th, and dim.
For example, I'm having a difficult time with chords like X6/9 and X7b9.
Isn't there a source which provides this information? I think the online
documentation could really benefit from a chart of chord symbols. All the
examples I've seen that use more complex chords only generate the chord
symbol from notes within "<>". I need to generate chord symbols
independently of the music on the staff.