zf.php won't recognize any command

Question

I'm using the ZF2 Skeleton application. I installed zftool using composer: composer require zendframework/zftool:dev-master but then, when I run zf.php I get the HTML of the Skeleton app homepage instead of a list of commands or something...

Any ideas? Thanks!

Edit:

This is the output from php-v:

PHP 5.6.23-2+deb.sury.org~trusty+1 (cli) 
Copyright (c) 1997-2016 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2016 Zend Technologies
    with Zend OPcache v7.0.6-dev, Copyright (c) 1999-2016, by Zend Technologies