User blog comment:Emptylord/League Client Update - New Champion Ratings/@comment-26815373-20160724194021/@comment-3974211-20160724201159

The official definition is "the ability to beneficially affect allies, such as shields and heals". This will likely include vision/scouting, but stealth would not be unless they add a champion that can stealth their allies. Detection is a grey area between control and utility, but since it disables the enemy and does directly do anything to your allies - it will likely be considered a form of control (if it's even rated at all).