Check out my scripts folder for two new uploads today (although I made them quite a bit ago).
tag, a simple wrapper for
vorbiscomment that gives a easier interface for manually tagging .opus and .ogg files.
More notable, however is
booksplit, which uses the script above to take a long audio file and a list of timecodes and automatically splits that file up into tracks/chapter files.
I use this when I can only find some audio content on YouTube and want to convert it to typical music files for listening offline, all with appropriate tags.
I just put up a video on all of this here.