Spurious Tool Use: When RL Agents Learn the Wrong Reason to Act

Mon, 14 Sep 2026 00:00:00 +0000

We study when reinforcement learning causes agents to invoke tools in response to superficial cues rather than task requirements. Experiments with synthetic question-answering and mathematical reasoning tasks identify conditions that encourage these shortcuts. A reward based on judging the necessity of each tool call helps agents avoid unnecessary tool use while maintaining task performance.

Tool Use | Bingbing Wen

Spurious Tool Use: When RL Agents Learn the Wrong Reason to Act