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arXiv · 2604.06177

WebExpert: domain-aware web agents with critic-guided expert experience for high-precision search

Yuelin Hu·Zhengxue Cheng·Ronghua Wu·Qunshan Gu·Hongwei Hu·Wei Liu·Qiao Liang·Li Song
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Abstract

Specialized web tasks in finance, biomedicine, and pharmaceuticals remain challenging due to missing domain priors: queries drift, evidence is noisy, and reasoning is brittle. We present WebExpert, a domain-aware web agent that we implement end-to-end, featuring : (i) sentence-level experience retrieval with topic merging and rule distillation, (ii) schemalight facet induction that bootstraps time,region,policy,industry facets from weak supervision instead of static hand-written lexicons, and (iii) preference-optimized planning that jointly improves query planning and retrieval via pairwise preference learning alongside a coverage-aware objective. At inference, a lightweight experience gate biases decoding toward active facets with fallback under low-retrieval confidence. On GAIA, GPQA, HLE, and WebWalkerQA, WebExpert improves Answer Exact Match (EM) by 1.5-3.6 pp over the strongest browsing baseline and reduces page hops. Analysis shows consistent gains and ablations on retrieval, topic merging, facet induction, and preference-aware training.

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Yuelin Hu, Zhengxue Cheng, Ronghua Wu, Qunshan Gu, Hongwei Hu, Wei Liu, Qiao Liang, Li Song. 2026-02-03. WebExpert: domain-aware web agents with critic-guided expert experience for high-precision search. https://arxiv.org/abs/2604.06177

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