Fatal error: Call to undefined function ctools_include()

I installed this module and when i visit a non admin page i see a blank page with this error:
Fatal error: Call to undefined function ctools_include() in /home/ordinata/domains/ordinatamente.com/public_html/sites/all/modules/metatag/metatag.module on line 244
This is because I have Chaos Tools Module not installed, because in module's description there's no mention to chaos tools dependency.
But in the chaos tools dependencies i can find "required by chaos tools".