Diagnosing Visual Reasoning: Challenges, Insights, and a Path Forward
Jing Bi, Guangyu Sun, Ali Vosoughi, Chen Chen, Chenliang Xu
TL;DR
The paper tackles visual reasoning challenges in multimodal LLMs, focusing on hallucinations and reliance on textual priors. It introduces a three-stage diagnostic framework and an agent-based architecture that couples LLM reasoning with lightweight visual modules to enable iterative refinement of reasoning chains. Across MMMU and MathVista, the approach yields substantial gains over a 7B baseline, matching or surpassing larger models by leveraging perceptual grounding with tools like OCR, captioning, and a Python interpreter. By releasing its framework and evaluation suite, it provides a practical path for diagnosing and improving visual reasoning in real-world settings.
Abstract
Multimodal large language models (MLLMs) that integrate visual and textual reasoning leverage chain-of-thought (CoT) prompting to tackle complex visual tasks, yet continue to exhibit visual hallucinations and an over-reliance on textual priors. We present a systematic diagnosis of state-of-the-art vision-language models using a three-stage evaluation framework, uncovering key failure modes. To address these, we propose an agent-based architecture that combines LLM reasoning with lightweight visual modules, enabling fine-grained analysis and iterative refinement of reasoning chains. Our results highlight future visual reasoning models should focus on integrating a broader set of specialized tools for analyzing visual content. Our system achieves significant gains (+10.3 on MMMU, +6.0 on MathVista over a 7B baseline), matching or surpassing much larger models. We will release our framework and evaluation suite to facilitate future research.
