According to Bolt 11, an invoice may contain a short description. However, what I fail to understand is who is sending this information to whom.
Since the invoice is usually generated by the payee, I'd argue that the short description is some information for the payer, like "Purchase: Product A, Product B". However, I've seen Lapps like tip boxes, where it is the payer who creates the message for the payee.
Or is the idea that the payee could propose a description, but the payer could then change it as he wants?