Hint-Augmented Re-ranking: Efficient Product Search using LLM-Based Query Decomposition
Yilun Zhu, Nikhita Vedula, Shervin Malmasi
TL;DR
This work tackles interpreting superlatives in e-commerce search by proposing a hint-augmented ranking framework that decomposes superlatives into domain-specific attribute-value hints to guide retrieval and lightweight reranking. It builds a large, specialized dataset of 21k queries and 470k products, with 1.07 million query–item pairs and three-way relevance labels, and demonstrates how offline LLM-generated hints (reasoning, brands, features, and alternative queries) can be transferred to small models to achieve production-scale latency. Across sparse and dense retrieval, plus listwise and pointwise reranking, hint augmentation yields substantial gains in ranking quality, with final 3B-sized, hint-enhanced pointwise models surpassing larger baselines (P@1 up to 64.39) while reducing compute by orders of magnitude. The approach maintains robustness across human and judge-based evaluations and offers a practical pathway to deploying reasoning-enabled search in high-traffic e-commerce settings. This work highlights how explicit, structured interpretations of superlative user queries can bridge natural language preferences and operational search pipelines, enabling efficient yet effective product retrieval and ranking.
Abstract
Search queries with superlatives (e.g., best, most popular) require comparing candidates across multiple dimensions, demanding linguistic understanding and domain knowledge. We show that LLMs can uncover latent intent behind these expressions in e-commerce queries through a framework that extracts structured interpretations or hints. Our approach decomposes queries into attribute-value hints generated concurrently with retrieval, enabling efficient integration into the ranking pipeline. Our method improves search performanc eby 10.9 points in MAP and ranking by 5.9 points in MRR over baselines. Since direct LLM-based reranking faces prohibitive latency, we develop an efficient approach transferring superlative interpretations to lightweight models. Our findings provide insights into how superlative semantics can be represented and transferred between models, advancing linguistic interpretation in retrieval systems while addressing practical deployment constraints.
