Surprisingly he goes into this issue near the beginning. They were created by Brian Blum based on the Remo Williams novels (The Destroyer novels). Kung Fu moves, run across water, incapacitate people by poking them, etc..
I always thought it was from the Shao Lin Monks. Apparently...no. It's Remo Williams. Which isn't a particularly strong prototype.
But that's my point.
The monk has no in universe purpose for its existence.
For example, rangers were based on Aragorn. But Aragorn and the Rangers of the North/South served a purpose in the world and as adventurers. The barbarians and the fighters represent untrained and trained warriors respectively.
The monk is based on an archetype that has no purpose in the world nor as an adventurer. It's just a collection of cool powers like a monster.