How to add description to photos uploaded to vkontakte album?

Question

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There is a task to upload photos to the group's album from the application. The task is solved, everything is loaded and working.
But there was a proposal from the client to add a description to the photos.
In theory, this should be a fairly obvious and standard action for the API, but after rummaging through the documentation, as well as in Google, I did not find the answer. Tell me please.