ALBUM tag; empty when absent.
ALBUM ARTIST values joined with , in tag order.
ARTIST values joined with , in tag order.
Always true: the track was resolved, whether or not any of its tags could be read.
DISCNUMBER tag as written; empty when absent.
GENRE values joined with , in tag order.
Whether the file embeds any of the five picture types.
Whether any of the five tags recognized by artwork.getLyrics exists, even an empty one.
Always true here; a failed call resolves with ApiFailure instead.
TITLE tag; empty when absent.
TRACKNUMBER tag as written, such as 3 or 3/12; empty when absent.
DATE tag as written; empty when absent.
Successful response from
artwork.getMetadata.