I am not sure if we are talking about the same thing. For example the .shared func of the PHPhotoLibrary class is for my understanding a way to get a reference to a singleton representing the photo library. I am referring to the iCloud shared photo library, as described here: How to use iCloud Shared Photo Library I would like to add photos to the iCloud shared library programmatically, with AppleScript or with a small command line tool. I want to use this in my export action of another program.

Well that is all fair and good, but for me it is not obvious how to use the PhotoKit API to share a photo in a shared library. I see the isFavorite property, but no isShared property or so. Could you give me more insight how this could work?