Add Book to Goodreads is a Chrome extension developed by Stephen Sulzberger. This free extension falls under the category of Browsers, specifically Add-ons & Tools. The main purpose of this extension is to allow users to easily add a book they are viewing to their Want to Read, Currently Reading, or Read shelf on Goodreads.

The extension simplifies the process of adding a book to a shelf without leaving the current page. It is designed to work on individual product pages and is compatible with popular sites like Amazon and Google Books, among others.

Add Book to Goodreads works by loading the "Add to My Books" widget using an ISBN or ASIN number scraped from the current tab. It automatically detects the first valid book identification number on the page, making it easy to add the book to Goodreads.

Please note that this extension requires the "Your data on all websites" and "Your tabs and browsing activity" permissions, as it is not limited to a specific book site.

Overall, Add Book to Goodreads is a convenient and efficient tool for avid readers who want to easily manage their reading lists on Goodreads without interrupting their browsing experience.