
UserProxyBench: Evaluating LLM User Simulators for Agent Benchmarks and Training
AABA4ET Workshop at NeurIPS · 2026
Introduces the User Fidelity Score to measure whether LLM user simulators follow their assigned roles. Across 375 enterprise tasks, changing only the user proxy shifts agent performance by 15.2 points, while 24.4% of successful episodes contain a user-specification violation.








