Jesse talks about that in the Droidcon NYC present...

# squarelibraries

[jw]

Jesse talks about that in the Droidcon NYC presentation. Ultimately it is up to you at what granularity you design, but our intent was to encode our design system components as defined by our design team. They are usually similar to regular widgets (like a Button) but where all the design choices are already made and so you're only deciding between things like primary or secondary style.