Cache-of-Thought: Master-Apprentice Framework for Cost-Effective Vision Language Model Reasoning

Mingyuan Wu, Jize Jiang, Haozhen Zheng, Meitang Li, Zhaoheng Li, Beitong Tian, Bo Chen, Yongjoo Park, Minjia Zhang, ChengXiang Zhai, Klara Nahrstedt


Abstract
Vision Language Models (VLMs) have achieved remarkable success in a wide range of vision applications of increasing complexity and scales, yet choosing the right VLM model size involves a trade-off between response quality and cost. While smaller VLMs are cheaper to run, they typically produce responses only marginally better than random guessing on benchmarks such as MMMU. In this paper, we propose Cache of Thought (CoT), a master–apprentice framework for collaborative inference between large and small VLMs. CoT manages high-quality query results from large VLMs (master) in a cache, which are then selected via a novel multi-modal retrieval and in-context learning to aid the performance of small VLMs (apprentice). We extensively evaluate CoT on various widely-recognized and challenging general reasoning benchmarks, and show that CoT increases overall reasoning performance by up to 7.7% under the same budget, and specifically boosts the reasoning performance of apprentice VLMs by up to 36.6%. Our code is available at https://github.com/UIUC-MONET/Cache-of-Thoughts.
Anthology ID:
2025.emnlp-main.97
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1895–1909
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URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.97/
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Cite (ACL):
Mingyuan Wu, Jize Jiang, Haozhen Zheng, Meitang Li, Zhaoheng Li, Beitong Tian, Bo Chen, Yongjoo Park, Minjia Zhang, ChengXiang Zhai, and Klara Nahrstedt. 2025. Cache-of-Thought: Master-Apprentice Framework for Cost-Effective Vision Language Model Reasoning. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 1895–1909, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
Cache-of-Thought: Master-Apprentice Framework for Cost-Effective Vision Language Model Reasoning (Wu et al., EMNLP 2025)
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