| title | Which Agent's Skill Should Change? Group-Relative Credit Assignment for Evolving Multi-Agent Teams |
|---|---|
| authors | Yanan Ma, Yang Wang, David Le, Chenhan Yuan, Yizheng Sun, Guangwei Zhang, Chenghao Xiao, Chenghua Lin, Imon Banerjee |
| date | 2026-10-19 |
| venue | arXiv (preprint, not peer reviewed) |
| id | arXiv:2610.27227 |
| affiliation | Mayo Clinic |
| upvotes | 15 (Hugging Face Daily Papers, 2026-11-01) |
| links | abs pdf hf code |
| abstract | Cooperative language-model agents can improve without weight updates by revising reusable skills, but only if a shared team reward is traced to the responsible agent and skill. Existing methods credit the skills present in each trajectory, yet presence is not responsibility: a harmful skill active in successful runs still earns positive credit. We present GRSE, Group-Relative Skill Evolution, which assigns behavioral credit by comparison: inspired by GRPO, it executes each question several times under the same skill libraries and contrasts the executions to credit agent--skill pairs, with structured diagnosis of failures. On HotpotQA and LoCoMo with two open-weight actors, GRSE outperforms MASkills, the closest prior method, on HotpotQA and every LoCoMo category except open-domain, with the largest gains on multi-hop questions (+6.7 and +3.2 F1). Its gains rest on better-grounded retrieval rather than answers given without evidence, and its learned skills transfer between the multi-hop tasks. GRSE is robust to corrupted libraries: starting from planted harmful skills, it credits every planted skill with the correct sign and recovers the score of a clean library (+6.3 points), whereas MASkills misattributes two and falls below its starting point. |
cite
@misc{ma2026which,
title={Which Agent's Skill Should Change? Group-Relative Credit Assignment for Evolving Multi-Agent Teams},
author={Yanan Ma and Yang Wang and David Le and Chenhan Yuan and Yizheng Sun and Guangwei Zhang and Chenghao Xiao and Chenghua Lin and Imon Banerjee},
year={2026},
eprint={2610.27227},
archivePrefix={arXiv},
url={https://arxiv.org/abs/2610.27227}
}