<http://schema.org/description>
"If you're going to put up an error message, try to make it one that the user can DO something about, and try to make it unambiguous. A good error message takes ... ..."^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.hanselman.com/blog/CommentView.aspx?guid=7234a414-1b5b-4412-b001-59489dde456d>