Controllable Conversations: Planning-Based Dialogue Agent with Large Language Models

Conversational agents powered by Large Language Models (LLMs) show superior performance in various tasks. Despite the better user understanding and human-like responses, their lack of controllability remains a key challenge, often leading to unfocused conversations or task failure. To address this challenge, we propose Planning-based Conversational Agents (PCA), a novel dialogue framework aimed at enhancing the controllability of LLM-driven agents. Specifically, our approach introduces Standard Operating Procedure (SOP) to regulate dialogue flow. To enable PCA to learn SOP, we curate a dataset comprising SOP-annotated multi-scenario dialogues, generated using a semi-automated role-playing system with GPT-4o and validated through strict manual quality control. Additionally, we propose a novel method that integrates Chain of Thought reasoning with supervised fine-tuning for SOP prediction and utilizes Monte Carlo Tree Search for optimal action planning during dialogues. Experimental results demonstrate the effectiveness of our method, such as achieving a 27.95% improvement in action accuracy compared to baseline models based on GPT-3.5 and also showing notable gains for open-source models. Dataset and codes are publicly available.