epubsum - An EPUB book file summarizer.
This is based on https://github.com/pszemraj/textsum, which handles plan text and PDF files.
The intent is not to generate good summaries - the model sometimes does an okay job at that but the output is generally pretty clunky. I wrote this primarily to generate summaries I could use for faster search. That said, if you're willing to put up with the clunky writing and occasional inaccuracies and nonsense, the content is generally pretty good for getting an overview of a book.
Run epubsum --help for help.