tool update

src/main.sh

@@ -373,6 +373,7 @@ case "${1:-}" in
   # This method reads the tags of the audio files in the specified directory.
   # If the audio files contain MusicBrainz tags, and they are consistent, then
   # a decoration file is written to that directory.
+  [ ! "$FFPROBE" ] && err "This option requires ffprobe. Quitting the application now." && exit 1
   [ ! "${2:-}" ] && err "You did not specify a directory." && exit 1
   [ ! -d "$2" ] && err "Path $2 does not point to a directory." && exit 1
   if ! decorate "$2"; then