τ2-Bench: Evaluating Conversational Agents in a Dual-Control Environment
By Victor Barres, Honghua Dong, Soham Ray, Xujie Si, Karthik Narasimhan. arXiv.org, 2025
322 citations recorded by the source corpus.
Existing benchmarks for conversational AI agents simulate single-control environments, where only the AI agent can use tools to interact with the world, while the user remains a passive information provider. This differs from real-world scenarios like technical support, where users need to actively participate in modifying the state of the (shared) world. In order to address this gap, we introduce $\tau^2$-bench, with four key contributions: 1) A novel Telecom dual-control domain modeled as a Dec-POMDP, where both agent and user make use of tools to act in a shared, dynamic environment that tests both agent coordination and communication, 2) A compositional task generator that programmatically creates diverse, verifiable tasks from atomic components, ensuring domain coverage and controlled complexity, 3) A reliable user simulator tightly coupled with the environment, whose behavior is constrained by tools and observable states, improving simulation fidelity, 4) Fine-grained analysis of agent performance through multiple ablations including separating errors arising from reasoning vs communication/coordination. In particular, our experiments show significant performance drops when agents shift from no-user to dual-control, highlighting the challenges of guiding users. Overall, $\tau^2$-bench provides a controlled testbed for agents that must both reason effectively and guide user actions.
Subfields: Artificial Intelligence, Social Psychology
View Paper: https://www.semanticscholar.org/paper/91c12fc38719eae97e812c6d59a37de5de288c75
Citations in the corpus
- DeepSeek-V3.2: Pushing the Frontier of Open Large Language Models (2025, unknown): “…et al., 2025), Terminal Bench 2.0, SWE-Verified (OpenAI, 2024b), SWE Multilingual (Yang et al., 2025), BrowseComp (Wei et al., 2025), BrowseCompZh (Zhou et al., 2025), 𝜏 2 -bench (Barres et al., 2025), MCP-Universe (Luo et al., 2025), MCP-Mark (EvalSys, 2025), and Tool-Decathlon (Li et al., 2025).”
- Kimi K2: Open Agentic Intelligence (2025, unknown): “For tool use tasks, we evaluate performance on τ 2 -Bench [3] and AceBench [7], which emphasize multi-turn tool-calling capabilities.”
- CUEing User Simulators: Calibrated User Embeddings for Multi-Turn Benchmarking (2026, unknown): “Domains Our primary evaluation uses 483 human episodes from the 𝜏 -USI airline and retail study with 𝜏 2 -Bench (Barres et al., 2026; Zhou et al., 2026).”