Replacing the manager LLM in a compound system with a deterministic merge operator beat generative managers by 0.048-0.076 task-score points

arXiv 2609.09815·medium signalXBlueskyLinkedInCopy link

UnitBoost argues a meta-agent concentrates three control decisions (assembling the answer, allocating later calls, deciding when to stop) into one opaque, order-sensitive model call, and replaces it with a defined operator: a task-given unit map turns worker outputs into slot-value proposals, a constrained argmax assembles the output, and unfilled slots become an explicit residual for the next round. On three held-out benchmarks it exceeded the best single candidate chosen with gold labels by 0.060-0.195 absolute points and input-matched generative managers by 0.048-0.076, improved six compound-system configurations by 0.013-0.182, and raised FanOutQA cell F1 from 0.4778 to 0.5524 via residual-directed rounds. The paper also names three conditions where no gain is available: one indivisible unit, unavailable unit identity, and an endpoint charging per emitted unit.