I want to build a chrome extension which I can use to directly add items to chrome's reading list. I have checked Chrome API Reference for bookmarks but I did not find what I was looking for. Does anyone know to programmatically add items the Chrome's reading list?
No, as of Feb 2023, it is not currently part of the API.
However the feature request has been logged in the Chromium issue tracker as #1238372
In a December 2022 comment the issue owner said "looking into creating an extensions API for the reading list sometime in summer 2023. No promises on if we meet this timeline but this is the goal."