Oral Tue, Jul 7, 2026 • 6:15 PM – 6:30 PM PDT HALL B2

Reinforcement Learning with Evolving Rubrics for Deep Research

Rulin Shao ⋅ Akari Asai ⋅ Shannon Shen ⋅ Hamish Ivison ⋅ Varsha Kishore ⋅ Jingming Zhuo ⋅ Xinran Zhao ⋅ Molly Park ⋅ Samuel Finlayson ⋅ David Sontag ⋅ Tyler Murray ⋅ Sewon Min ⋅ Pradeep Dasigi ⋅ Luca Soldaini ⋅ Faeze Brahman ⋅ Scott Yih ⋅ Sherry Wu ⋅ Luke Zettlemoyer ⋅ Yoon Kim ⋅ Hannaneh Hajishirzi ⋅ Pang Wei Koh

Abstract

Deep research agents perform multi-step research to produce long-form, well-attributed answers. However, most open deep research agents are trained on easily verifiable short-form QA tasks via reinforcement learning with verifiable rewards, which does not extend to realistic long-form tasks. We address this with Reinforcement Learning with Evolving Rubrics (RLER), where rubrics are constructed and maintained to co-evolve with the policy model during training. This allows the rubrics to incorporate newly explored information from search and contrasting model responses, enabling better fact checking and more discriminative on-policy feedback. Using RLER, we develop Deep Research Tulu (DR Tulu-8B), the first fully open model that is directly trained for open-ended, long-form deep research. Across four long-form deep research benchmarks in science, healthcare, and general domains, DR Tulu-8B substantially outperforms existing open deep research agents (by 15.6% over Tongyi DR on average) and matches or exceeds proprietary deep research agents (by 0.7% over OpenAI DR on average), while being significantly smaller and cheaper per query (1000x cheaper than OpenAI DR per query).