SEMA-RAG: A Self-Evolving Multi-Agent Retrieval-Augmented Generation Framework for Medical Reasoning

Yongfeng Huang, Ruiying Chen, James Cheng


Abstract
Retrieval-Augmented Generation (RAG) is widely employed to mitigate risks such as hallucinations and knowledge obsolescence in medical question answering, yet its predominantly single-round, static retrieval paradigm misaligns with the multi-stage process of clinical reasoning. This compressed workflow induces two structural deficiencies: question-to-query translation often lacks clinically grounded semantic interpretation, and retrieval lacks iterative sufficiency feedback, making it difficult to form reliable evidence chains. We argue that both issues stem from a deeper cause—overloading a single reasoning chain with heterogeneous tasks of interpretation, exploration, and adjudication—and that the remedy is to reconstruct the workflow via task decoupling and dynamic multi-round exploration. To this end, we propose the Self-Evolving Multi-Agent framework **SEMA-RAG**, which assigns these roles to three specialist agents: **Interpreter Agent** for clinical schema interpretation, **Explorer Agent** for sufficiency-driven self-evolving retrieval, and **Arbiter Agent** for evidence adjudication and answer selection. Across five benchmarks and five LLM backbones, SEMA-RAG improves the strongest baseline by **+6.46** accuracy points on average, measured per backbone.
Anthology ID:
2026.findings-acl.917
Volume:
Findings of the Association for Computational Linguistics: ACL 2026
Month:
July
Year:
2026
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San Diego, California, United States
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Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
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Findings
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Association for Computational Linguistics
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Pages:
18423–18442
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.917/
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Cite (ACL):
Yongfeng Huang, Ruiying Chen, and James Cheng. 2026. SEMA-RAG: A Self-Evolving Multi-Agent Retrieval-Augmented Generation Framework for Medical Reasoning. In Findings of the Association for Computational Linguistics: ACL 2026, pages 18423–18442, San Diego, California, United States. Association for Computational Linguistics.
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SEMA-RAG: A Self-Evolving Multi-Agent Retrieval-Augmented Generation Framework for Medical Reasoning (Huang et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.917.pdf
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