arXiv Computation and Language

The Collaboration Tax: How Much LLM Multi-Agent Systems Pay to Coordinate

arXiv AI
Sep 28

Multi-agent Scaling Across Disjunctive and Compensatory Tasks

The paper introduces Steiner’s taxonomy of group tasks to study how multi‑agent large language model (LLM) teams scale on disjunctive versus compensatory tasks. By modeling agents as conditionally independent given the item, it shows that plurality voting converges to the modal answer while averaging converges to the item‑level bias. Experiments with 13 open‑weight models and up to 30 agents reveal that disjunctive tasks benefit from larger teams, whereas compensatory tasks like Fermi estimation see little improvement, highlighting that task structure and aggregation method fundamentally determine team scaling.

By Carolina Fortuna, Blaz Bertalanic