# τ-Voice: Benchmarking Full-Duplex Voice Agents on Real-World Domains

arXiv: https://arxiv.org/abs/2603.13686 · HTML: https://mlsanity.com/paper/2603.13686/

## Key facts

- Cited by 36 papers in the map (data through 14 Oct 2026).
- Placed in General LLM agent frameworks and benchmarks, one of 16 directions in LLM agents and tool use.
- Builds on 14 of its 57 references that are in the map.
- First posted on arXiv 14 Mar 2026.

## Placed in

- LLM agents and tool use / [General LLM agent frameworks and benchmarks](https://mlsanity.com/agents/general-llm-agent-frameworks-and-benchmarks/)

## Builds on (most cited first, 14 of 14)

- [τ-bench: A Benchmark for Tool-Agent-User Interaction in Real-World Domains](https://mlsanity.com/paper/2406.12045/) (2024)
- [τ2-Bench: Evaluating Conversational Agents in a Dual-Control Environment](https://mlsanity.com/paper/2506.07982/) (2025)
- [VoiceBench: Benchmarking LLM-Based Voice Assistants](https://mlsanity.com/paper/2410.17196/) (2024)
- [AudioBench: A Universal Benchmark for Audio Large Language Models](https://mlsanity.com/paper/2406.16020/) (2024)
- [Full-Duplex-Bench: A Benchmark to Evaluate Full-duplex Spoken Dialogue Models on Turn-taking Capabilities](https://mlsanity.com/paper/2503.04721/) (2025)
- [SpokenWOZ: A Large-Scale Speech-Text Benchmark for Spoken Task-Oriented Dialogue Agents](https://mlsanity.com/paper/2305.13040/) (2023)
- [SD-Eval: A Benchmark Dataset for Spoken Dialogue Understanding Beyond Words](https://mlsanity.com/paper/2406.13340/) (2024)
- [Talking Turns: Benchmarking Audio Foundation Models on Turn-Taking Dynamics](https://mlsanity.com/paper/2503.01174/) (2025)
- [Full-Duplex-Bench-v2: A Multi-Turn Evaluation Framework for Duplex Dialogue Systems with an Automated Examiner](https://mlsanity.com/paper/2510.07838/) (2025)
- [ParaS2S: Benchmarking and Aligning Spoken Language Models for Paralinguistic-aware Speech-to-Speech Interaction](https://mlsanity.com/paper/2511.08723/) (2025)
- [Audio MultiChallenge: A Multi-Turn Evaluation of Spoken Dialogue Systems on Natural Human Interaction](https://mlsanity.com/paper/2512.14865/) (2025)
- [VocalBench: Benchmarking the Vocal Conversational Abilities for Speech Interaction Models](https://mlsanity.com/paper/2505.15727/) (2025)
- [S2S-Arena: Evaluating Paralinguistic Instruction Following in Speech-to-Speech Models](https://mlsanity.com/paper/2503.05085/) (2025)
- [WildSpeech-Bench: Benchmarking End-to-End SpeechLLMs in the Wild](https://mlsanity.com/paper/2506.21875/) (2025)

## Built on by (most cited first, 30 of 36)

- [Full-Duplex-Bench-v3: Benchmarking Tool Use for Full-Duplex Voice Agents Under Real-World Disfluency](https://mlsanity.com/paper/2604.04847/) (2026)
- [GaP: A Graph-as-Policy Multi-Agent Self-Learning Harness For Variational Automation Tasks](https://mlsanity.com/paper/2607.05369/) (2026)
- [SWE-INTERACT: Reimagining SWE Benchmarks as User-Driven Long-Horizon Coding Sessions](https://mlsanity.com/paper/2606.30573/) (2026)
- [VAmoS Bench: Voice Agent Simulation Bench](https://mlsanity.com/paper/2607.27453/) (2026)
- [IHBench: Evaluating Post-Interruption Recovery in Voice Agents with Structured Workflows](https://mlsanity.com/paper/2606.19595/) (2026)
- [DuplexWorld: Can voice agents help you get through the day?](https://mlsanity.com/paper/2608.10716/) (2026)
- [MSI-Bench: Evaluating Multi-Speaker Voice Interaction for Collaborative AI Agents](https://mlsanity.com/paper/2609.24812/) (2026)
- [MTVA-Bench: Evaluating the Language Model Inside Cascaded Voice Agents](https://mlsanity.com/paper/2609.20152/) (2026)
- [A frontend-backend architecture for tool calls in full-duplex speech models](https://mlsanity.com/paper/2609.19334/) (2026)
- [SpeechGym: An Audio-Native Gym for Training Voice Agents via Reinforcement Learning](https://mlsanity.com/paper/2608.26432/) (2026)
- [DuplexSpeechBench-IFEval: Evaluating Implicit Instruction Following in Full-Duplex Voice Agents](https://mlsanity.com/paper/2609.03423/) (2026)
- [Qwen-Audio-3.1-Realtime: Towards Reliable Agentic Voice Interaction](https://mlsanity.com/paper/2609.25176/) (2026)
- [SALMONN-duo: Adaptive Dual-System Coordination for Full-Duplex Voice Agents](https://mlsanity.com/paper/2609.34247/) (2026)
- [DRIP-R: A Benchmark for Decision-Making and Reasoning Under Real-World Policy Ambiguity in the Retail Domain](https://mlsanity.com/paper/2605.07699/) (2026)
- [TOBench: A Task-Oriented Omni-Modal Benchmark for Real-World Tool-Using Agents](https://mlsanity.com/paper/2605.16909/) (2026)
- [SEATauBench: Progressively Adapting Tool-Agent-User Evaluation Into Low-Resource Southeast Asian Languages](https://mlsanity.com/paper/2606.28715/) (2026)
- [Just A Rather Very Intelligent Spoken Agent](https://mlsanity.com/paper/2607.16610/) (2026)
- [CallScreenBench: Benchmarking Small Language Models as Phone Secretaries](https://mlsanity.com/paper/2608.01033/) (2026)
- [PACE: A Playback-Aligned Context Engine for LLM-Based Full-Duplex Voice Dialogue](https://mlsanity.com/paper/2608.07631/) (2026)
- [When Patients Cut In: Extending Clinical Conversational AI Safety to Interruptions](https://mlsanity.com/paper/2608.29241/) (2026)
- [τ-Elicitation: Benchmarking multi-turn entity extraction in voice agents](https://mlsanity.com/paper/2609.13602/) (2026)
- [Evaluating Real-Time Voice Agents: From Component Quality to Grounded Outcomes](https://mlsanity.com/paper/2609.30798/) (2026)
- [Clarify the User or Verify the World? Uncertainty Routing for Proactive Agents](https://mlsanity.com/paper/2609.32255/) (2026)
- [Trust and Task Completion in the World of Consumer AI Agents](https://mlsanity.com/paper/2609.33017/) (2026)
- [APEX-Voice: Can Voice Agents Complete Professional Workflows Through Full-Duplex Interaction](https://mlsanity.com/paper/2609.34973/) (2026)
- [τ-Multilingual: Benchmarking Voice Agents Across Languages](https://mlsanity.com/paper/2609.35820/) (2026)
- [Almost Human, Except When It Matters: VoxParity and the Decisions a Voice Should Change](https://mlsanity.com/paper/2609.35922/) (2026)
- [VAmoS Part Deux: Harder, More Realistic Voice-Agent Simulation](https://mlsanity.com/paper/2609.38512/) (2026)
- [Talk2Agent: Benchmarking Voice Interfaces for Text Agents](https://mlsanity.com/paper/2609.38867/) (2026)
- [DuplexSpeechBench-Document Grounding: Benchmarking Document Grounding and Hallucinations in Voice Agents](https://mlsanity.com/paper/2610.00316/) (2026)

## Abstract (arXiv)

Full-duplex voice agents--systems that listen and speak simultaneously--are rapidly moving from research to production. However, existing evaluations address conversational dynamics and task completion in isolation. We introduce τ-voice, a benchmark for evaluating voice agents on grounded tasks with real-world complexity: agents must navigate complex multi-turn conversations, adhere to domain policies, and interact with the environment. The framework extends τ2-bench into a novel voice agent benchmark combining verifiable completion of complex grounded tasks, full-duplex interaction, and realistic audio--enabling direct comparison between voice and text performance. A controllable and realistic voice user simulator provides diverse accents, realistic audio environments, and rich turn-taking dynamics; by decoupling simulation from wall-clock time, the user simulator can use the most capable LLM without real-time constraints. We evaluate task completion (pass@1) and voice interaction quality across 278 tasks: while GPT-5 (reasoning) achieves 85%, voice agents reach only 31--51% under clean conditions and 26--38% under realistic conditions with noise and diverse accents--retaining only 30--45% of text capability; qualitative analysis confirms 79--90% of failures stem from agent behavior, suggesting that observed failures primarily reflect agent behavior under our evaluation setup. τ-voice provides a reproducible testbed for measuring progress toward voice agents that are natural, conversational, and reliable.