Embed metadata to the video file. Also embeds chapters/infojson if present unless --no-embed-chapters/–no-embed-info-json are used (Alias: --add-metadata)
What do you mean descriptions? Like the video’s description body text? If so, yes. Gimme one moment to get on my computer, and I’ll edit this comment to include the command args.
EDIT: This is the specific shell alias I use when I’m archiving videos for backup.