Shouldn't it use NIP-32 for better cross compatibility?
The concept is interesting; I've also tried #pinstr. I just don't know what the idea behind using an uncatalogued #kind (33889) in #nips of the #nostr protocol.
https://pinstr.app/p/npub16mwf24pwrzut0tkz79rppa2uxddta0k8du7mnevvy4rxr5ze8gxq4w2myx/Nostr%20BOTS
Discussion
Maybe, I'm not completed familiar with all the nips.