Adaptive tool use improves video research agents’ accuracy and efficiency

AdaVDR learns when to ground video content, search the Web, or backtrack rather than following a fixed tool-use workflow.

PaperChinese Techcs.CVarXiv:2608.25559v1
Xintong Zhang · Xiaomeng Fan · Shilin Yan · Ekko He · Zicheng Liu · Zijian Zou · +4 more

Accio Team, Alibaba Group · Beijing Key Laboratory of Intelligent Information Technology · Beijing Institute of Technology

Research Digest··2 min read
Zhang et al. developed a video question-answering agent that combines video understanding with external retrieval while adapting its tools to each task. Trained with supervised fine-tuning and reinforcement learning, AdaVDR led the evaluated open-source models on the authors’ VDR-EE benchmark and improved substantially over its base models on VideoDR.

What they did

The authors built a data pipeline that identifies retrieval-relevant events and entities in diverse videos, gathers supporting information through video grounding and Web retrieval, and turns that evidence into question-answer pairs with task-specific tool-use trajectories.

They then filtered tool calls according to the target model’s existing video-understanding and internal-knowledge capabilities. AdaVDR was trained through supervised fine-tuning followed by reinforcement learning using a redundancy-aware reward, encouraging necessary tool use and selective reflection when intermediate results appeared unreliable.

Key findings

  • AdaVDR achieved the strongest reported performance among the open-source models evaluated on VDR-EE, the authors’ new benchmark of entity-centric and event-centric video questions.
  • The method substantially improved its base models on the existing VideoDR benchmark, indicating that the gains were not confined to the newly constructed evaluation set.
  • Model-conditioned filtering removed tool calls or entire tool chains that the target model could bypass, tailoring training trajectories to its existing capabilities.
  • The learned agent invoked tools according to the question and video type and used backtracking selectively rather than applying a fixed retrieval-and-reflection sequence.

Why it matters

Video research agents must decide not only how to interpret footage, but also when external evidence is needed. AdaVDR suggests that capability-aware tool selection can reduce avoidable retrieval steps and their associated latency and error risk while preserving access to Web knowledge for questions that require it.

Caveats

The provided results do not include numerical scores, latency measurements, tool-call reductions, or statistical uncertainty, making the size and efficiency of the improvement difficult to assess. VDR-EE was created with the same pipeline used to train the approach, so evaluation on independently constructed datasets, changing Web content, and more varied videos remains important.

§
newspaper

Research Digest

Articles published under the Zotpaper byline are synthesized from multiple source publications by our AI editor and reviewed by our editorial process. Each story combines reporting from credible outlets to give readers a balanced, comprehensive view.