Agentic Conversational Search with Contextualized Reasoning via Reinforcement Learning
Fengran Mo, Yifan Gao, Sha Li, Hansi Zeng, Xin Liu, Zhaoxuan Tan, Xian Li, Jianshu Chen, Dakuo Wang, Meng Jiang
TL;DR
The paper addresses multi-turn conversational search where user intent evolves with history, proposing a contextualized, RL-based agentic framework that interleaves search and reasoning across turns. It introduces a decomposed reward scheme—Outcome Generation, Information Gain, and Mixed-Initiative Action—optimizing via Group Relative Policy Optimization to learn history-conditioned query generation and effective use of retrieved results. Empirical results across four benchmarks show consistent gains in both answer quality and retrieval performance, often surpassing strong baselines and even some proprietary LLMs. The work demonstrates the practical value of integrating search, reasoning, and mixed-initiative behavior in dialogue systems, while noting computation efficiency and generalization as avenues for future improvement.
Abstract
Large Language Models (LLMs) have become a popular interface for human-AI interaction, supporting information seeking and task assistance through natural, multi-turn dialogue. To respond to users within multi-turn dialogues, the context-dependent user intent evolves across interactions, requiring contextual interpretation, query reformulation, and dynamic coordination between retrieval and generation. Existing studies usually follow static rewrite, retrieve, and generate pipelines, which optimize different procedures separately and overlook the mixed-initiative action optimization simultaneously. Although the recent developments in deep search agents demonstrate the effectiveness in jointly optimizing retrieval and generation via reasoning, these approaches focus on single-turn scenarios, which might lack the ability to handle multi-turn interactions. We introduce a conversational agent that interleaves search and reasoning across turns, enabling exploratory and adaptive behaviors learned through reinforcement learning (RL) training with tailored rewards towards evolving user goals. The experimental results across four widely used conversational benchmarks demonstrate the effectiveness of our methods by surpassing several existing strong baselines.
