You might be thinking of Zendo [1]. "Zendo is a game of inductive logic in which one player, the Master, creates a rule that the rest of the players, as Students, try to figure out by building and studying configurations of the game pieces. The first student to correctly guess the rule wins."
Yes, that's the one, thanks!
This is incredible. I copied and pasted your description into ChatGPT:
he game you're describing sounds like "Zendo," which is a game of inductive logic designed by Kory Heath. In Zendo, players use colored plastic pieces called "Icehouse pyramids" that come in different sizes and colors. The moderator, or "Master," creates a secret rule and builds two structures, one that follows the rule (marked with a white stone) and one that doesn't (marked with a black stone). The players, or "Students," then take turns building new structures and asking the Master if they follow the rule or not. The goal is for the Students to correctly guess the secret rule by observing the examples and counterexamples provided by the Master.
The original edition was kind of cheap and plastic feeling, but it's the sort of thing that could be done nowadays with really high quality components.