Sublime Text Custom Build source.less not working

I'm trying to create an script for compiling LESS running via Sublime Text Build Systems.

This is the content of my LESS.sublime-build file:

{
    "cmd": [ "node", "${packages}/buildLessWithLessDrama/buildLessWithLessDrama.js", "$file","$file_name","$file_path" ],
    "selector": "source.less"
}

It works perfectly if I choose Tools -> Build System -> LESS. But it doesn't in "Automatic" mode. Does anyone have an idea why?