Most Helpful Girl
Many things could contribute to that compliment, but personally when I call a guy cute, its either because he has a genuinely kind personality (if I know him well), or his face is well... Cute! He could have larger eyes than usual, a rounder face, etc. or its just another way of calling a guy hot or attractive without seeming as creepy or coming on too strong haha.
Most Helpful Guy
Usually when a girl says a guy is cute, it usually means he plays an extremely mean Chess game, often centering around the castling tactic.