As mentioned quickly in another thread, Bibliograph is an appview for applications to build against to build an opportunistic experience for books and reviewing books on ATProto. It’s currently powering a project of mine that’s in alpha, Livtet and was born of discussion with some folks on how to handle book discovery on-protocol.
If a book is not known to Bibliograph, it searches Google Books and OpenLibrary for it. Failing that, one can attempt to create a unverified book and someone with the librarian account label and approve it; a bit similar to how Hardcover, Fable and OpenLibrary currently operates; permitting transparency.
I’d love to get feedback on it, have people kick its tires and look at its code at GitHub - olamaelcu/bibliograph: An AppView for interfacing with bilbographic information on ATProto · GitHub