REFACT: Adaptive Fact Restatement for Compact and Faithful Chain-of-Thought Reasoning

· Source: cs.CL updates on arXiv.org · Field: Technology & Digital — Artificial Intelligence & Machine Learning · Depth: Expert, extended

Summary

ReFact is an adaptive fact-restatement citation framework designed to enhance large language models' (LLMs) long-form reasoning by ensuring contextual grounding and preventing reasoning drift. It trains models to selectively determine when a reasoning step requires evidence and at what granularity to restate source facts, avoiding both unsupported inferences and indiscriminate fact copying. Optimized via a two-stage Supervised Fine-Tuning (SFT) to Reinforcement Learning (RL) pipeline, ReFact uses a citation-utility reward to encourage well-formed, source-traceable, and answer-sufficient cited facts. Experiments on LongBench, LV-Eval, and ConFiQA demonstrate that ReFact improves long-context QA and counterfactual faithfulness, reducing average reasoning length by approximately 50% on LongBench v1 for Qwen3-4B and 8B models, while producing denser, more answer-sufficient reasoning traces.

Key takeaway

For Machine Learning Engineers developing LLMs for long-context reasoning, ReFact offers a robust approach to improve faithfulness and efficiency. You should consider implementing adaptive fact-restatement frameworks to ensure reasoning steps are contextually grounded and avoid relying on conflicting parametric knowledge. This method yields more compact and accurate traces, reducing token consumption while maintaining answer-bearing evidence.

Key insights

ReFact adaptively grounds LLM reasoning in context by selectively restating answer-sufficient facts, yielding compact and faithful traces.

Principles

Method

ReFact uses a two-stage SFT-to-RL pipeline. SFT establishes citation format, then RL optimizes a policy with a reward combining format, accuracy, traceability, and answerability criteria.

In practice

Topics

Code references

Best for: AI Engineer, Research Scientist, AI Scientist, Machine Learning Engineer, NLP Engineer

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Editorial summary, takeaway, and curation by AIssential. Original article published by cs.CL updates on arXiv.org.