Tried on rock crabs for a while. It's pretty useless. It might run 30 minutes without failure if you're lucky. It's very obvious it's a bot, it doesn't pick a spot where crabs are, it keeps walking to a crab that's sleeping to wake it up. It doesn't attack crabs that are moving around. So when the aggression timer runs out it runs away, wakes half the crabs up and never attacks them, leaving only three crabs left that it attacks.
For some reason it worked for a while on the eastern rock crabs, then suddenly it only ever wanted to fight the western crabs and doesn't want to fight the eastern crabs anymore.
Most of the time it works for 30 minutes, then it will stand in the same spot a few tiles away from a crab and do nothing.