Single-Agent Generation Surpasses Multi-Agent Systems in Semantic Diversity
Cui Encheng, Shaowen Peng, Kazuhiro Ito, XU Jinsha, Hisada Shohei, Shoko Wakamiya, Eiji Aramaki
Abstract
Multi-Agent Systems (MAS) are commonly used to improve reasoning diversity and robustness by simulating interactions among agents with distinct roles. However, prior work often entangles the contribution of the multi-agent architecture with that of prompt conditioning, making the source of observed diversity gains unclear. We address this confound with a controlled study on divergent thinking tasks, using identical prompt conditioning for MAS and single agent baseline. Under these matched conditions, single agent setups consistently outperform multi-agent systems in semantic diversity. We attribute this gap to information visibility: parallel agents often converge on overlapping ideas, whereas a single agent model can condition on its own generation to avoid redundancy. We further find that a Multi-Output strategy, which prompts a single agent to produce multiple responses within a single inference pass, achieves the highest diversity without degrading logical validity. Together, these results point to a more efficient and effective way to expand diversity, with implications for the design of more efficient agentic frameworks.- Anthology ID:
- 2026.findings-acl.1894
- Volume:
- Findings of the Association for Computational Linguistics: ACL 2026
- Month:
- July
- Year:
- 2026
- Address:
- San Diego, California, United States
- Editors:
- Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
- Venue:
- Findings
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 37993–38008
- Language:
- URL:
- https://preview.aclanthology.org/ingest-acl/2026.findings-acl.1894/
- DOI:
- Cite (ACL):
- Cui Encheng, Shaowen Peng, Kazuhiro Ito, XU Jinsha, Hisada Shohei, Shoko Wakamiya, and Eiji Aramaki. 2026. Single-Agent Generation Surpasses Multi-Agent Systems in Semantic Diversity. In Findings of the Association for Computational Linguistics: ACL 2026, pages 37993–38008, San Diego, California, United States. Association for Computational Linguistics.
- Cite (Informal):
- Single-Agent Generation Surpasses Multi-Agent Systems in Semantic Diversity (Encheng et al., Findings 2026)
- PDF:
- https://preview.aclanthology.org/ingest-acl/2026.findings-acl.1894.pdf