Steven,
Not sure if you already include this tag, but maybe what a06lp is asking for is the "Terms of Use" tag (USER). According to the ID3 tag document I looked at, it gave this description for that tag:
"This frame contains a brief description of the terms of use and ownership of the file. More detailed information concerning the legal terms might be available through the "WCOP" frame. Newlines are allowed in the text. There may only be one "USER" frame in a tag."
taken from:
http://www.id3.org/id3v2.3.0.html#sec4.23
Kinda matches up to "situation/description".
Maybe what would be helpful, Steven, could you indicate a link to look up the specification that you go by, and ao6lp can compare what your doing to what he is asking? It almost sounds like a difference in terminology.
Hope this was helpful.
David.