I had hoped to use these which "can be attached to various objects" to identify items that belong to the GCAH. Unfortunately it looks like tags are only available, via either API or the UI, with regards to user records. Even tho instances, holdings records, and items are all capable of being associated with "arbitrary tags" via API on the back end the UI is not capable of displaying or using them. Darn. It remains to be seen whether or not tags will be of any use to us at Drew.