App Store Connect API: why do I only have to provide a checksum when uploading app screenshots and not for app event screenshots?

When uploading app screenshots, I have to provide a sourceFileChecksum and uploaded flag: https://developer.apple.com/documentation/appstoreconnectapi/appscreenshotupdaterequest/data/attributes

But that's not the case for app event screenshots, I only have to provide the uploadedflag: https://developer.apple.com/documentation/appstoreconnectapi/appeventscreenshotupdaterequest/data/attributes

The same is true for app previews and app event video clips.

Why is this different?

The old XML API required checksums for screenshots, and in fact I think the Transporter uploader relied on comparing checksums to determine whether to actually send the file

Events are newer and weren't supported in the XML API.

Fundamentally the answer is "it just does".

App Store Connect API: why do I only have to provide a checksum when uploading app screenshots and not for app event screenshots?
 
 
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