A weak puzzle walkthrough records every input. A stronger one explains why the board refuses to move. That distinction matters in traffic-sorting puzzles, where a correct tap can still be useless if a garage exit, crossing lane, or temporary holding space remains blocked.
I used Car Sort level 13 as a small case study for a better hint model. The useful unit is not “tap car number seven.” It is a dependency: this vehicle cannot leave until that lane opens; that lane cannot open until a matching garage accepts its front car.
Model the board as dependencies
The visible board can be represented as a directed graph. Cars and blockers are nodes. An edge from A to B means A must move before B becomes actionable. The graph does not need to reproduce the game engine. It only needs to describe the decisions a player can verify on screen.
type MoveNode = {
