aiqbench analysis
This paper introduces AcCoRD, a new benchmark designed to test how frontier LLMs handle evolving user preferences rather than just static queries. The study reveals that while current models can resolve initial ambiguities, they struggle significantly with preferences that emerge or shift during interaction, highlighting a critical gap in uncertainty modeling for real-world agent collaboration. This resource is essential for advancing the robustness of AI agents in dynamic environments like shopping and travel planning.
AcCoRD: Evaluating User-Agent Collaboration Under Realistic User Preference Dynamics
arXiv:2608.27818v1 Announce Type: new Abstract: User preferences in user-agent collaboration are rarely static and fully-specified upfront: preferences are formed, revealed, adjusted, and relaxed during interaction. Existing benchmarks for evaluating user-agent collaboration focus almost exclusively on resolving underspecified preferences, thereby failing to capture the richer dynamics of real-world interaction. We introduce AcCoRD, a user-agent collaboration benchmark requiring agents to handle diverse user preference dynamics in two domains: online shopping and travel planning. We evaluate five frontier LLMs under two prompting strategies: vanilla ReAct, and an uncertainty-guided variant that prompts models to identify and resolve ambiguity about user preferences. Our results reveal that frontier models can handle underspecification but struggle to satisfy preferences that emerge or evolve mid-interaction and require more sophisticated uncertainty modeling. Further, prompting alone fails to elicit the required uncertainty recognition. We release AcCoRD as a resource for developing agents that can navigate the full complexity of real-world user preferences.
Abstract:User preferences in user-agent collaboration are rarely static and fully-specified upfront: preferences are formed, revealed, adjusted, and relaxed during interaction. Existing benchmarks for evaluating user-agent collaboration focus almost exclusively on resolving underspecified preferences, thereby failing to capture the richer dynamics of real-world interaction. We introduce AcCoRD, a user-agent collaboration benchmark requiring agents to handle diverse user preference dynamics in two domains: online shopping and travel planning. We evaluate five frontier LLMs under two prompting strategies: vanilla ReAct, and an uncertainty-guided variant that prompts models to identify and resolve ambiguity about user preferences. Our results reveal that frontier models can handle underspecification but struggle to satisfy preferences that emerge or evolve mid-interaction and require more sophisticated uncertainty modeling. Further, prompting alone fails to elicit the required uncertainty recognition. We release AcCoRD as a resource for developing agents that can navigate the full complexity of real-world user preferences.
Artificial Intelligence (cs.AI)
arXiv:2608.27818 [cs.AI]
(or arXiv:2608.27818v1 [cs.AI] for this version)
https://doi.org/10.48550/arXiv.2608.27818 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website.
Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them.
Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs.
Full text under the publisher's open licence · 240 words
Related coverage

Digital States 2026: AI Moves From Experiment to Infrastructure
govtech.com · Sep 24, 2026

Inside the suddenly explosive world of AI safety
The Verge · Sep 17, 2026

Senior SWE-Bench: Evaluating Coding Agents Like Senior Engineers
Snorkel AI Blog · Jul 16, 2026

Dreams of alignment in a world without politics
LessWrong · Sep 24, 2026