not only that question, but how do you access metadata for map that are published or viewable on ArcGIS Online?
Use and Constraints and tags are the required. That being said there are so many other areas that assist users with determining if what has been developed is what is needed.
I like to error on the side of information overload in the description (unless I'm testing) so users can make a decision without contacting anyone. Metadata (in my eyes) keeps the calls away so I can continue "playing" with new stuff!
Retrieving data ...