Best practices for documenting the domain model

While ideally entities and attributes are named so as to be self-documenting, there are times that it is desirable to add some additional information.  While the documentation property is available for both entities and attributes, accessing that documentation (even with documentation panel open) requires a fair bit of clicking.  As I embark on using Mendix I wonder in practice what works best.  Does it turn out that documentation property suffices and that you get in the habit of consulting it as needed?  Do people use annotations or separate documents for this purpose?