EGR: Embedding-Native Generative Retrieval with a Shared LLM

Xiaodong Liu; Congfei Zhang; Hsiang-wei Chao; Siman Wang; Tong Zhao; Xiao Bai; Vincent Zhang; Jingxiao Ma; Zhe Liu; Wenfeng Zhuo; Zichu Li; Jitin Krishnan; Yunzhi Zhou; Yajun Wang; Jinchao Li; Yu Zhang

arXiv · 2607.23038

EGR: Embedding-Native Generative Retrieval with a Shared LLM

Xiaodong Liu·Congfei Zhang·Hsiang-wei Chao·Siman Wang·Tong Zhao·Xiao Bai·Vincent Zhang·Jingxiao Ma·Zhe Liu·Wenfeng Zhuo·Zichu Li·Jitin Krishnan·Yunzhi Zhou·Yajun Wang·Jinchao Li·Yu Zhang

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Abstract

Generative retrieval is increasingly popular in large-scale recommendation and advertising systems, yet current methods introduce practical complications. Semantic-ID methods rely on quantization, mutable identifier vocabularies, and token-to-item grounding; embedding-based pipelines train the item encoder separately from the query generator, which limits user-item alignment. We propose EGR, an Embedding-Native Generative Retrieval framework for recommendation and advertising. EGR uses a single shared LLM to learn item representations from item metadata and user representations from interaction histories in one embedding space. Items are indexed directly as dense vectors, and user histories are encoded as dense retrieval queries. Joint contrastive training groups related items and aligns queries with their target items. We evaluate EGR on public benchmarks, industrial data, and live deployment. EGR outperforms published baselines on Amazon Reviews; on Snap DPA, it scales with data, handles cold-start items, and benefits from multimodal input. In production, EGR delivers a +2.91% conversion-rate lift, simplifying system design while improving retrieval quality and ad performance.

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Xiaodong Liu, Congfei Zhang, Hsiang-wei Chao, Siman Wang, Tong Zhao, Xiao Bai, Vincent Zhang, Jingxiao Ma, Zhe Liu, Wenfeng Zhuo, Zichu Li, Jitin Krishnan, Yunzhi Zhou, Yajun Wang, Jinchao Li, Yu Zhang. 2026-07-25. EGR: Embedding-Native Generative Retrieval with a Shared LLM. https://arxiv.org/abs/2607.23038

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