Stopping him

Alt+Shift+O stops him from any app, at any time, even if the chat is closed.

What stopping does

Whatever he was doing ends between one step and the next, and he says so in the chat. The shortcut works on your computer itself, so it works even if your internet does not.

Stop in the chat

While he works, Stop sits next to what he is doing, on the taskbar and on onsay.dev. Either one stops the same session.

Changing your mind

Say something new while he works and he reads it before his next step, so you can steer him without stopping him.