Difficulty-aware topology selection beats always-hierarchical by 4.1 points at 40% of the cost.

Across 614 problems from APPS, HumanEval+ and LiveCodeBench, hierarchical collaboration was worth 2.4 pass@1 points on the easiest problems and 21.1 on the hardest, at a flat ~10x token cost throughout (arXiv 2609.13890). DATS predicts each topology's success probability and picks the one maximizing predicted success minus cost, using a graph network treating topologies as ordered nodes, which is worth 1.7 points over a flat multi-label head. Held to 40% of always-hierarchical spend it reached 77.7% pass@1 against 73.6%. Holds across four model variants spanning 14 capability points.