Create Collection API call does not return _id of created item

I’m creating an item in a collection using the Create Collection Item API call: Create Collection Item which works fine, however, the response does not include the _id of the item I just created.

It would make sense to return the created _id so that I can store that as a reference back in my system, so that I can use it for subsequent calls to Update Collection Item.

Right now I have to manually find the item I created with the API call, paste it back into my system so that I can then make Update calls…

Why would the _id not be returned from the create item call?

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Create Item returns _id. Not sure why it’s absent from the docs.