I agree it's not a "Perception" check in the modern D&D sense.Well, again, the move is not 'Search for Secret Doors' and the text of Discern Realities talks about 'When you closely study a situation or person' as the trigger. A room is neither a situation nor a person. Now, maybe I'm at odds with others here, but I DO NOT consider DR to be a 'Perception Check'. It is an investigative move! It isn't an attempt to find some specific thing, it's an attempt to learn all you can about a SITUATION (IE lets say "what's up with the people in this room?") or a specific person (and I would say 'In context' not patting them down or something, though that might trigger it). I see it as basically a 'Sherlock Holmes' move.
If all you are doing is feeling around on a wall, then I agree, you are not going to learn "who's in charge here" or anything like that, so the move is NOT appropriate.
I do think a room, or even a wall, could be a situation. From DW p 68:
To discern realities you must closely observe your target. That usually means interacting with it or watching someone else do the same. You can’t just stick your head in the doorway and discern realities about a room. You’re not merely scanning for clues - you have to look under and around things, tap the walls, and check for weird dust patterns on the bookshelves. That sort of thing.
Discerning realities isn’t just about noticing a detail, it’s about figuring out the bigger picture.
Discerning realities isn’t just about noticing a detail, it’s about figuring out the bigger picture.
And p 69 has this example of play:
Omar: I don’t trust this room - I’m going to poke around a little. I take out my tools and start messing with stuff. I pull candlesticks and tap the walls with my hammer. My usual tricks.
GM: Discern realities?
Omar: Oh yes. I discern all the realities. I got a 12. I want to know “What here is not as it appears to be?”
GM: Well, it’s obvious to you that the wall on the north side of the room has a hollow spot. The stones are newer and the mortar is fresher, probably a hidden alcove or passageway.
GM: Discern realities?
Omar: Oh yes. I discern all the realities. I got a 12. I want to know “What here is not as it appears to be?”
GM: Well, it’s obvious to you that the wall on the north side of the room has a hollow spot. The stones are newer and the mortar is fresher, probably a hidden alcove or passageway.
Where the action moves from "feeling around on a wall" to "close study" that may permit "figuring out the bigger picture" seems like a matter of judgement. In the example of play, Omar makes it clear by talking about the use of tools and the messing with stuff.
This also helps establish the consequence-space if the roll is 6-. Eg someone who is "messing with stuff" is in danger of triggering a trap!