arXiv AI By Yanze Jiang, Mingxuan Li, Yuhao Wang, Shengfang Zhai, Jiaheng Zhang

Don't Solve, Just Compare: Tiny Advisors for Runtime Intervention in LLM Agents

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The paper introduces COTA, a lightweight comparison-only framework that enables runtime intervention in large language model agents by using a tiny comparator to evaluate whether alternative continuations outperform the agent’s current proposal. Instead of generating full solutions, the comparator only judges sampled alternatives, and repeated comparisons decide when to intervene. Experiments on WebShop, ALFWorld, and tau^3-Retail show that COTA improves performance across nine settings and outperforms existing baselines, demonstrating that constructive intervention can be effective even with a much weaker auxiliary model.

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