MotifAgent: Learning Molecular Assembly through Multi-Agent Collaboration for Chemical Language Understanding

Jinjia Feng, Wenda Wang, Zhewei Wei


Abstract
Large Language Models (LLMs) have shown great potential in molecular understanding by aligning molecular representations with text. However, existing approaches remain limited to static motif recognition without comprehending the generative principles—the connection rules governing how motifs assemble into valid topological structures. To address this challenge, we introduce **MotifAgent**, a multi-agent reinforcement learning framework inspired by emergent collective intelligence. We formulate molecular assembly as a collaborative problem where each motif is represented by an agent sharing a common LLM backbone, learning connection rules through explicit inter-motif negotiation rather than implicit sequence memorization. Key innovations include: (1) dynamic inter-agent negotiation for modeling motif connections; (2) Set-based Behavioral Cloning for learning multiple topologically equivalent assembly paths; (3) topology-aware reward shaping with MAPPO to maintain chemical validity while optimizing target properties. Extensive experiments demonstrate that MotifAgent achieves state-of-the-art performance across molecular property prediction, description generation, and reaction prediction tasks, with our generalist model surpassing specialized expert models.
Anthology ID:
2026.findings-acl.2023
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
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Publisher:
Association for Computational Linguistics
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Pages:
40700–40739
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URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.2023/
DOI:
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Cite (ACL):
Jinjia Feng, Wenda Wang, and Zhewei Wei. 2026. MotifAgent: Learning Molecular Assembly through Multi-Agent Collaboration for Chemical Language Understanding. In Findings of the Association for Computational Linguistics: ACL 2026, pages 40700–40739, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
MotifAgent: Learning Molecular Assembly through Multi-Agent Collaboration for Chemical Language Understanding (Feng et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.2023.pdf
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