๐ค AI Summary
Existing benchmarks lack fine-grained evaluation capabilities for multimodal AI agents performing subtasks in web navigationโsuch as date selection and scroll positioning. This paper introduces WebNav, the first benchmark explicitly designed for GUI-level subtask evaluation. Built upon the Web ARChive (WARC), it provides a reproducible, sandboxed, dynamic web interaction environment that faithfully reconstructs real-world interface behaviors. Methodologically, we initialize models via supervised fine-tuning (SFT) and propose verifiable-reward reinforcement learning (RLVR) to mitigate data scarcity. Experiments show that our best-performing model achieves a success rate of 64.8%; RLVR improves the SFT baseline from 48.8% to 52.8%, significantly outperforming multiple state-of-the-art models. This work fills a critical gap in fine-grained web interaction evaluation and establishes a new paradigm for assessing controllable, low-level operational capabilities of multimodal agents.
๐ Abstract
Training web agents to navigate complex, real-world websites requires them to master $ extit{subtasks}$ - short-horizon interactions on multiple UI components (e.g., choosing the correct date in a date picker, or scrolling in a container to extract information). We introduce WARC-Bench (Web Archive Benchmark), a novel web navigation benchmark featuring 438 tasks designed to evaluate multimodal AI agents on subtasks. WARC-Bench enables sandboxed interactions with dynamic and realistic webpages using Web ARChive files. We show that WARC-Bench is challenging for leading computer-use models, with the highest observed success rate being 64.8%. To improve open source models on subtask, we explore two common training techniques: supervised fine-tuning (SFT) and reinforcement learning with verifiable rewards (RLVR). Experiments show that SFT models obtain a 48.8% success rate on the benchmark. Training with RLVR over SFT checkpoints, even in data-scarce settings, improves the score to 52.8% on WARC-Bench, outperforming many frontier models. Our analysis concludes that mastering these subtasks is essential for robust web planning and navigation, and is a capability not extensively evaluated by existing benchmarks.