YouTube’s Watch Later list is the perfect way to keep track of interesting videos you come across but don’t have time to watch at the moment. Since rolling out that feature on the YouTube website and the embedded players, developers have been asking for ways to interact with the Watch Later list via the YouTube Data API. We’re happy to announce that this is now possible.
As explained in our documentation, the YouTube Data API treats the Watch Later list like a playlist, and the normal playlist operations (additions, retrievals, modifications) can all be performed on the Watch Later list. While every YouTube user has their own Watch Later list, it’s important to keep in mind that by default it’s a private playlist, so it will not normally be accessible unless you’re making an authenticated request as the list’s owner.
If you have any questions about using the Data API to work with the Watch Later list, please let us know in our developer forum.
—Jeff Posnick, YouTube API Team