Foles impressed last campaign with standout statistical representation, although some critics have labelled his impact a consequence of the quality of players around him.
"Nick, he wants to play, he wants to get better. He's playing lights out even in camp, but he still wants to be at a higher level," McCoy revealed to reporters.
"He's at that peak where people know him like, 'Man, this Foles, is he that good?' Because you see the stats, you see the numbers.
"I think this is the year he blows 'em out like, 'Yeah, I'm Nick Foles. I'm Philadelphia's quarterback. I'm the guy.' And this is the year he blows it away."
Foles was selected as one of the most promising youngsters at the NFL Draft in 2012.