I know this has been said above, but I just wanted to add a little weight to the request: Either the serial or barcode (same in my case) of the tape, or the library slot location the tape was returned to in the notification, would be incredibly helpful.
It was also explained succinctly above, but just to be clear, this necessary for our various customers who have the combination of:
1) a robotic library where various tapes might have been used.
2) no onsite I.T. staff, so an admin has to take tapes to either the courier or fireproof safe, an admin to whom we can't give access to Veeam.
Anyway, sorry for the repetition, just wanted to make sure you (Veeam) knew how handy this would be. What I'd do would be to set the admin to receive alerts, that way they could do what they needed to do without me having to manually check Veeam on each of our clients where this is necessary.