AICLCVLGMay 30, 2025

Open CaptchaWorld: A Comprehensive Web-based Platform for Testing and Benchmarking Multimodal LLM Agents

arXiv:2505.24878v110 citationsh-index: 4
Originality Incremental advance
AI Analysis

This addresses a critical bottleneck for deploying web agents in real-world applications by providing a comprehensive testing platform.

The paper tackles the problem of evaluating multimodal LLM agents' ability to solve interactive CAPTCHA puzzles, introducing Open CaptchaWorld as a benchmark with 20 CAPTCHA types and 225 puzzles, and finds that state-of-the-art agents achieve at most 40.0% success rates compared to 93.3% for humans.

CAPTCHAs have been a critical bottleneck for deploying web agents in real-world applications, often blocking them from completing end-to-end automation tasks. While modern multimodal LLM agents have demonstrated impressive performance in static perception tasks, their ability to handle interactive, multi-step reasoning challenges like CAPTCHAs is largely untested. To address this gap, we introduce Open CaptchaWorld, the first web-based benchmark and platform specifically designed to evaluate the visual reasoning and interaction capabilities of MLLM-powered agents through diverse and dynamic CAPTCHA puzzles. Our benchmark spans 20 modern CAPTCHA types, totaling 225 CAPTCHAs, annotated with a new metric we propose: CAPTCHA Reasoning Depth, which quantifies the number of cognitive and motor steps required to solve each puzzle. Experimental results show that humans consistently achieve near-perfect scores, state-of-the-art MLLM agents struggle significantly, with success rates at most 40.0% by Browser-Use Openai-o3, far below human-level performance, 93.3%. This highlights Open CaptchaWorld as a vital benchmark for diagnosing the limits of current multimodal agents and guiding the development of more robust multimodal reasoning systems. Code and Data are available at this https URL.

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