Where is your Apple Music library?

Normally, that’s just part of your Apple Music setup, but if you’re talking about locally stored data, you’d want to follow the instructions here. 

Hey there. Thanks for the reply. Perhaps I didn’t ask the question well. Here’s a scenario: 
 

In Music if I’m listing to some random song there’s always an option to “Add to Library” which will “store” a copy of the song in my curated library. 

If I’m listening via the Sonos app the only options I see are the Add Song to My Sonos and Add Song to Sonos playlist. I have no option to add to my Music Library.

I’m assuming this is done so folks stay in the Sonos ecosystem but it kind of sucks if I’m listening to a new track and I want it saved to my Music library in addition to any Sonos playlists. 

@hobaSound 

The Sonos API offers the possibility to integrate this function. But it depends on the music service itself if they are doing so. For example with my Deezer account it’s possible to add content from within the Sonos app to my Deezer accounts library/ favorites. 
So people have to ask Apple Music support for integrating the feature. 

The Apple API has the POST as well. I’m curious why Sonos isn’t using it:

https://developer.apple.com/documentation/applemusicapi/add_a_resource_to_a_library

Imho it’s a matter of the direction and who is using which API… And as far as i know the music sevices get the offer to use the Sonos API. They can take it or they can leave it… thats the way how Sonos works. Each music service itself is responsible for its Sonos appearance. 
Sonos is not going to use other services by their APIs. That would be a complete different system design. 

Indeed, Sonos has one API, as indicated in the Sonos partners page. For them to keep up with well over a hundred individual APIs from each streaming company would be a Herculean effort. They chose a different business model. 

@Schlumpf @Airgetlam both make great points. 

I guess I had made the incorrect assumption that the onus was on Sonos but it makes sense that Apple would be the ones to implement. It makes it even MORE strange that it’s not an option with that being the case. 

Great discussion folks. I really appreciate it. 

It’s gets messier when you factor in that Apple and Sonos are both partners and competitors in different markets.  Does Apple want you to have more features through Sonos so that you are happier with their music service?  Sure….but maybe they prefer you buy a homepod instead.  Likewise, Sonos wants you to be happy with Apple music on Sonos, but they would rather you be happier with Sonos radio. To what extent this plays a part?  Who knows.  And it certainly isn’t limited to Apple and Sonos.  And really, even services like Spotify and Sirius XM don’t support all features via Sonos (compared to their own streaming apps), even though they don’t have competing hardware to sell you.