titleRethinking Reasoning-Intensive Retrieval: Evaluating and Advancing Retrievers in Agentic Search Systems
authorsYilun Zhao, Jinbiao Wei, Tingyu Song, Siyue Zhang, Chen Zhao, Arman Cohan
date2026-05-05
venuearXiv (preprint, not peer reviewed)
idarXiv:2605.04018
affiliationYale University
upvotes26 (Hugging Face Daily Papers, 2026-11-01)
linksabs pdf hf code
abstractReasoning-intensive retrieval aims to surface evidence that supports downstream reasoning rather than merely matching topical similarity. This capability is increasingly important for agentic search systems, where retrievers must provide complementary evidence across iterative search and synthesis. However, existing work remains limited on both evaluation and training: benchmarks such as BRIGHT provide narrow gold sets and evaluate retrievers in isolation, while synthetic training corpora often optimize single-passage relevance rather than evidence portfolio construction. We introduce BRIGHT-Pro, an expert-annotated benchmark that expands each query with multi-aspect gold evidence and evaluates retrievers under both static and agentic search protocols. We further construct RTriever-Synth, an aspect-decomposed synthetic corpus that generates complementary positives and positive-conditioned hard negatives, and use it to LoRA fine-tune RTriever-4B from Qwen3-Embedding-4B. Experiments across lexical, general-purpose, and reasoning-intensive retrievers show that aspect-aware and agentic evaluation expose behaviors hidden by standard metrics, while RTriever-4B substantially improves over its base model.

cite

@misc{zhao2026rethinking,
  title={Rethinking Reasoning-Intensive Retrieval: Evaluating and Advancing Retrievers in Agentic Search Systems},
  author={Yilun Zhao and Jinbiao Wei and Tingyu Song and Siyue Zhang and Chen Zhao and Arman Cohan},
  year={2026},
  eprint={2605.04018},
  archivePrefix={arXiv},
  url={https://arxiv.org/abs/2605.04018}
}