TRACE-CS: A Hybrid Logic–LLM System for Explainable Course Scheduling

We present TRACE-cs, a novel hybrid system that combines logical reasoning with large language models (LLMs) to address contrastive queries in course scheduling problems. TRACE-cs leverages logic-based techniques to encode scheduling constraints and generate provably correct explanations, while utilizing an LLM to process natural language queries and refine logical explanations into user-friendly responses. This system showcases how combining symbolic KR methods with LLMs creates explainable AI agents that balance logical correctness with natural language accessibility, addressing a fundamental challenge in deployed scheduling systems.