Usage: opustags --help
       opustags [OPTIONS] INPUT
       opustags [OPTIONS] -o OUTPUT INPUT

Options:
  -h, --help              print this help
  -V, --version           print version
  -o, --output FILE       write the modified tags to this file
  -i, --in-place [SUFFIX] use a temporary file then replace the original file
  -y, --overwrite         overwrite the output file if it already exists
      --stream ID         select stream for the next operations
  -l, --list              display a pretty listing of all tags
      --no-color          disable colors in --list output
  -d, --delete FIELD      delete all the fields of a specified type
  -a, --add FIELD=VALUE   add a field
  -s, --set FIELD=VALUE   delete then add a field
  -D, --delete-all        delete all the fields!
      --full              enable full file scan
      --export            dump the tags to standard output for --import
      --import            set the tags from scratch basing on stanard input
  -e, --edit              spawn the $EDITOR and apply --import on the result

See the man page, opustags.1, for extensive documentation.