abcde-musicbrainz-tool: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/abcde-musicbrainz-tool - from package: abcde

You may install the required package with command apt-get install {package}
Error in other languages:
abcde-musicbrainz-tool: bevel nie gevind nie
abcde-musicbrainz-tool: comandă negăsită
abcde-musicbrainz-tool: comando não encontrado
abcde-musicbrainz-tool: commande introuvable
abcde-musicbrainz-tool: command not found
abcde-musicbrainz-tool: käsku ei ole
abcde-musicbrainz-tool: không tìm thấy lệnh
abcde-musicbrainz-tool: komanda nerasta
abcde-musicbrainz-tool: Kommando nicht gefunden.
abcde-musicbrainz-tool: kommandot finns inte
abcde-musicbrainz-tool: komut yok
abcde-musicbrainz-tool: nie znaleziono polecenia
abcde-musicbrainz-tool: níor aimsíodh an t-ordú
abcde-musicbrainz-tool: no se encontró la orden
abcde-musicbrainz-tool: no s'ha trobat l'ordre
abcde-musicbrainz-tool: opdracht niet gevonden
abcde-musicbrainz-tool: parancs nem található
abcde-musicbrainz-tool: perintah tidak ditemukan
abcde-musicbrainz-tool: príkaz nenájdený
abcde-musicbrainz-tool: příkaz nenalezen
abcde-musicbrainz-tool: команда не найдена
abcde-musicbrainz-tool: командата не е открита
abcde-musicbrainz-tool: 命令找不到
abcde-musicbrainz-tool: コマンドが見つかりません