Patrice Béchard

Just-in-time Episodic Feedback Hinter: Leveraging Offline Knowledge to Improve LLM Agents Adaptation

Hadi Nekoei

Aman Jaiswal

Patrice Béchard

Oleh Shliazhko

Orlando Marquez Ayala

Mathieu Reymond

Massimo Caccia

Alexandre Drouin

Sarath Chandar

Alexandre Lacoste

Large language model (LLM) agents perform well in sequential decision-making tasks, but improving them on unfamiliar domains often requires … (voir plus)costly online interactions or fine-tuning on large expert datasets. These strategies are impractical for closed-source models and expensive for open-source ones, with risks of catastrophic forgetting. Offline trajectories offer reusable knowledge, yet demonstration-based methods struggle because raw traces are long, noisy, and tied to specific tasks. We present Just-in-time Episodic Feedback Hinter (JEF Hinter), an agentic system that distills offline traces into compact, context-aware hints. A zooming mechanism highlights decisive steps in long trajectories, capturing both strategies and pitfalls. Unlike prior methods, JEF Hinter leverages both successful and failed trajectories, extracting guidance even when only failure data is available, while supporting parallelized hint generation and benchmark-independent prompting. At inference, a retriever selects relevant hints for the current state, providing targeted guidance with transparency and traceability. Experiments on MiniWoB++, WorkArena-L1, and WebArena-Lite show that JEF Hinter consistently outperforms strong baselines, including human- and document-based hints.

2025-10-05

ArXiv (prépublication)

arxiv.org