if he’s not behind a wall maybe turn his field to water and see if he says anything, kills you, or changes what he’s doing 🙂
then you’d be sure, for what that’s worth; it can be hard to tell at times we had a player with an alt that was probably only ever seen digging clay in the same spot for hours but he had two devices, one was doing the ‘fun’ stuff and one was digging clay, and would respond to questions so was clearly paying attention. and when I get on a hypnotic planting spree myself it might start looking very robotic 😀 that said, I’m sure there ARE bots, but equally sure that admin is trying to work these things out as he can.