Follow the Path: Reasoning over Knowledge Graph Paths to Improve Large Language Model Factuality

Mike Zhang, Johannes Bjerva, Russa Biswas


Abstract
We introduce fs1, a simple yet effective method that improves the factuality of reasoning traces by sourcing them from large reasoning models and grounding them by conditioning on knowledge graph (KG) paths. We fine-tune eight instruction-tuned Large Language Models (LLMs) on 3.9K factually grounded reasoning traces and rigorously evaluate them on six complex open-domain question-answering (QA) benchmarks encompassing 23.9K questions. Our results demonstrate that our fs1-tuned model consistently outperforms instruction-tuned counterparts with parallel sampling by 6-14 absolute points (pass@). Our detailed analysis shows that fs1 considerably improves model performance over more complex questions (requiring 3 or more hops on KG paths) and numerical answer types compared to the baselines. Furthermore, in single-pass inference, we notice that smaller LLMs show the most improvements. While prior works demonstrate the effectiveness of reasoning traces primarily in the STEM domains, our work shows strong evidence that anchoring reasoning to factual KG paths is a critical step in transforming LLMs for reliable knowledge-intensive tasks.
Anthology ID:
2026.findings-acl.561
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:
11574–11590
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URL:
https://preview.aclanthology.org/ingest-acl/2026.findings-acl.561/
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Cite (ACL):
Mike Zhang, Johannes Bjerva, and Russa Biswas. 2026. Follow the Path: Reasoning over Knowledge Graph Paths to Improve Large Language Model Factuality. In Findings of the Association for Computational Linguistics: ACL 2026, pages 11574–11590, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
Follow the Path: Reasoning over Knowledge Graph Paths to Improve Large Language Model Factuality (Zhang et al., Findings 2026)
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https://preview.aclanthology.org/ingest-acl/2026.findings-acl.561.pdf
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