Mine was awesome with other fish. I never had a problem with him bothering any of the other fish in my tank (I had a Tomini, a Sailfin, a pair of gold stripe maroons, an occilaris, an orange lined goby, a lawnmower, a snowflake eel, a flame angel and a lemonpeel).
He left all my crabs and snails alone (which is why I think they're "with caution"... they love the inverts). I also had a skunk cleaner he used more than any other fish in the tank. But if he saw my peppermints out, he'd munch on them.