🤖 AI Summary
Building task-oriented dialogue systems for high-stakes domains (e.g., law, healthcare) remains challenging for non-technical domain experts due to the difficulty of low-threshold definition, debugging, and optimization of dialogue behaviors.
Method: We propose a novel framework featuring (1) a structured heterogeneous graph that explicitly encodes domain expert knowledge, enabling zero-shot, interpretable, and editable dialogue policy generation; and (2) a human-in-the-loop, LLM-assisted iterative alignment mechanism that supports efficient, annotation-free, and retraining-free optimization.
Contribution/Results: Evaluated on STAR and MultiWOZ, our framework achieves state-of-the-art performance among inference-only models on STAR and matches mainstream baselines on MultiWOZ. It significantly enhances expert-driven iterative development efficiency and controllability—enabling rapid, transparent, and precise customization of dialogue logic without ML expertise.
📝 Abstract
It is often challenging to teach specialized, unseen tasks to dialogue systems due to the high cost of expert knowledge, training data, and high technical difficulty. To support domain-specific applications - such as law, medicine, or finance - it is essential to build frameworks that enable non-technical experts to define, test, and refine system behaviour with minimal effort. Achieving this requires cross-disciplinary collaboration between developers and domain specialists. In this work, we introduce a novel framework, CoDial (Code for Dialogue), that converts expert knowledge, represented as a novel structured heterogeneous graph, into executable conversation logic. CoDial can be easily implemented in existing guardrailing languages, such as Colang, to enable interpretable, modifiable, and true zero-shot specification of task-oriented dialogue systems. Empirically, CoDial achieves state-of-the-art performance on the STAR dataset for inference-based models and is competitive with similar baselines on the well-known MultiWOZ dataset. We also demonstrate CoDial's iterative improvement via manual and LLM-aided feedback, making it a practical tool for expert-guided alignment of LLMs in high-stakes domains.