Visual Studio 2013 is awesome, now with syntax highlight and autocomplete for .less files. But does it also generate the respective CSS files? Do I need to install
.less
If you don't want to install plugins in your Visual Studio, you can use an external compiler.
Currently I'm using Koala, every time you save your LESS file he will compile it automatically in your output folder.
Take a look at the official LESS page about GUI Compilers.