In NSFileProviderItemProtocol I am able to use the extendedAttributes property call to add my custom extended attributes to my NSFileProviderReplicatedExtension extension files.
Given that the Finder uses com.apple.metadata:kMDItemFinderComment extended attribute for file comments I thought it would be possible to populate my files with useful comments provided by the third part API.
Unfortunately I seems to be unable to do so as if com.apple.metadata.... fields were inaccessible from the FP extension.
Is there any way to achieve this ?