# LLM-Driven Usefulness Judgment for Web Search Evaluation

arXiv: https://arxiv.org/abs/2504.14401 · HTML: https://mlsanity.com/paper/2504.14401/

## Key facts

- Cited by 3 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 19 Apr 2025.

## Built on by (most cited first, 3 of 3)

- [D-Models and E-Models: Diversity-Stability Trade-offs in the Sampling Behavior of Large Language Models](https://mlsanity.com/paper/2601.17865/) (2026)
- [AuthorityBench: Benchmarking LLM Authority Perception for Reliable Retrieval-Augmented Generation](https://mlsanity.com/paper/2603.25092/) (2026)
- [SEEK: Skill-Routed Evaluation with Evolvable Knowledge for Industrial Search](https://mlsanity.com/paper/2609.29803/) (2026)

## Abstract (arXiv)

Evaluation is fundamental in optimizing search experiences and supporting diverse user intents in Information Retrieval (IR). Traditional search evaluation methods primarily rely on relevance labels, which assess how well retrieved documents match a user's query. However, relevance alone fails to capture a search system's effectiveness in helping users achieve their search goals, making usefulness a critical evaluation criterion. In this paper, we explore an alternative approach: LLM-generated usefulness labels, which incorporate both implicit and explicit user behavior signals to evaluate document usefulness. We propose Task-aware Rubric-based Usefulness Evaluation (TRUE), a rubric-driven evaluation method that employs iterative sampling and reasoning to model complex search behavior patterns. Our findings show that (i) LLMs can generate moderate usefulness labels by leveraging comprehensive search session history incorporating personalization and contextual understanding, and (ii) fine-tuned LLMs improve usefulness judgments when provided with structured search session contexts. Additionally, we examine whether LLMs can distinguish between relevance and usefulness, particularly in cases where this divergence impacts search success. We also conduct an ablation study to identify key metrics for accurate usefulness label generation, optimizing for token efficiency and cost-effectiveness in real-world applications. This study advances LLM-based usefulness evaluation by refining key user metrics, exploring LLM-generated label reliability, and ensuring feasibility for large-scale search systems.