mdtool: command not found

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/mdtool - from package: monodevelop

You may install the required package with command apt-get install {package}

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