When the DM says something like “The room appears to be empty” or “so you touch the object?”
Fun DM tip: always do that. Even if it really is empty or nothing will happen. Really helps curb meta gamming and can get some funny reactions. My favorite is asking how they open the door or asking “so you just stand in front of it and open it normally” then suddenly they’re trying to describe a totally abnormal way of opening a door that doesnt involve them being in front of it
niko thats mean
When my players roll a bad perception check I like to say, “there *seems* to be nothing there.” Especially if there is actually nothing there.