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arXiv · 2608.09408

DREAM Technical Report

Abstract

Industrial recommender systems commonly use cascaded retrieval, ranking, and re-ranking pipelines. Although efficient, these pipelines fragment information and objectives across modules, rely on rigid rules, and have limited awareness of real-time intent, leaving session-level shifts among browsing, comparison, and purchase insufficiently addressed. We present DREAM (Developing Recommender Engine with Agentic Methods), an autonomous optimization control architecture that adds a perception-aware, orchestrable, and auditable policy layer atop existing pipelines without replacing them. DREAM has two core components. First, a three-tier Intent Engine fuses on-device signals into structured L0/L1/L2 intent representations; its edge-cloud trigger chain reduces reporting volume to approximately 8.7%. Second, a Meta Engine uses a MetaModel for layered M1-to-M2-to-M3 reasoning: intent summarization, strategy planning informed by Strategy Memory, and parameter translation. It dispatches the resulting parameters through a unified outlet with safety guardrails. A Reward Dual Loop continuously optimizes both components by combining offline simulation for strategy-space exploration with online feedback for outcome calibration, forming a cycle of generation, execution, evaluation, and experience accumulation. Large-scale A/B tests on Taobao's homepage feed show that re-ranking control alone improves IPV by 2.06%, Core IPV by 2.39%, and GMV by 0.88%. Extending control to fine ranking raises these gains to 2.71%, 3.06%, and 1.31%, respectively, while consistently improving PV by more than 1%. These gains require neither replacement of pipeline models nor compromise of serving stability, supporting agentic meta-control as a viable paradigm for industrial recommendation.

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Bin Zhang, Bowen Zheng, Chao Yi, Chengyu Lai, Dian Chen, Dimin Wang, Gaoyang Guo, Jialin Zhu, Jian Wu, Jing Yu, Jiuning Lin, Lingqing Zhang, Lingyun Zheng, Mao Zhang, Mingming Pan, Ruiquan Lan, Shuai Zhong, Wen Chen, Wendong Zhang, Xiaodong Zhu, Xuan Chen, Xunke Xi, Yifan Lu, Yiheng Wang, Yue Zeng, Yujie Luo, Yuning Jiang, Zhe Hu, Zhibo Xiao, Zihong Huang, Binbin Cao, Bo Zheng, Danning Wang, Dixuan Wang, Ge Fan, Haixia Wu, Han Zhu, Hao Fang, Haoming Chen, Huiping Chu, Jian Wang, Jianjun Wu, Jiawei Wu, Jiaxin Yu, Jingwen Liu, Jinzhe Shan, Kai Meng, Kai Zhang, Keqin Xu, Kewei Zhu, Lang Tian, Leihui Chen, Li Chen, Licheng Xu, Lide Xiao, Ruitong Zhang, Shiyao Peng, Silu Zhou, Tao Wang, Wei Shi, Wenjun Yang, Xiang Chen, Xiang Gao, Xiao Ren, Xu Liu, Xuwen Wang, Yang Li, Yeqiu Yang, Yi Hu, Yichen Yuan, Yinnan Song, Yipeng Yu, Yuan Liu, Yunqi Gao, Zhiliang Huang, Zhujin Gao, Zongyuan Wu. 2026-08-10. DREAM Technical Report. https://arxiv.org/abs/2608.09408

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