In MagicDraw, notes are used not just to show/enter documentation for the element, but also to display derived information, which is an extremely powerful feature (I’m not aware of another tool that supports this capability).
Let’s say you want to show inherited properties for a class. You can attach a note to an element, press the “…” handler and select any metaproperty (in MagicDraw you can easily define your own metaproperty with its own derivation rules without any programming):
It is also possible to show metaproperties on the shape itself. Choose the following menu item for the element on which you want to display metaproperties: