arXiv AI By Pritish Mishra, Ishaan Kumar, Akshat Mandoli, Sudarshan Kamath

MTVA-Bench: Evaluating the Language Model Inside Cascaded Voice Agents

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MTVA-Bench is a new benchmark designed to evaluate the language model component of cascaded voice agents under realistic conditions. It simulates callers with an LLM, mocks backend tool responses, and scores both tool‑call correctness and conversational quality using two LLM judges, covering 49 agents, 490 scenarios, and 7 languages. The benchmark reveals that while models perform similarly on tool selection, they differ widely in argument handling, rule compliance, and dialogue quality, highlighting the nuanced challenges of real‑world voice interactions.

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