Laurence F. Sheldon, Jr. just gave a great cable tag definition on the NANOG mailing list.

The tags should have a short (two or three word) description, the authority for the patch (person's name or position, order number, or trouble ticket number) and where the [other]{.underline} end of the patch is, followed by where [this]{.underline} is. (For short cords "this" will cover both ends, probably.

This was too long to tweet, so here it is.