I love keeping track of my reading, and though I keep my library up in micro.blog, I also track my lists in Things. So, naturally, a Shortcut.
This is intended to be run from the Share Sheet in Apple Books. Because Books aren't actually shared as a first-class citizen object, I use some regex to get the title of the book from the URL that is shared (the only parameter, sad face), search that in the store, then get all the real parameters from the search result.
The result is then loving placed under one of three headings in my Books list in Things, but you can modify this based on the examples. I also have handling if you wanted to let the Shortcut return more than one result from the Book Store search, but so far, all of mine have worked.
Enjoy!