Pre-trained large language models (LLMs) have recently achieved better
generalization and sample efficiency in autonomous web navigation. However, the
performance on real-world websites has still suffered from (1) open domainness,
(2) limited context length, and (3) lack of inductive bias on HTML. We
introduce WebAgent, an LLM-driven agent that can complete the tasks on real
websites following natural language instructions. WebAgent plans ahead by
decomposing instructions into canonical sub-instructions, summarizes long HTML
documents into task-relevant snippets, and acts on websites via generated
Python programs from those. We design WebAgent with Flan-U-PaLM, for grounded
code generation, and HTML-T5, new pre-trained LLMs for long HTML documents
using local and global attention mechanisms and a mixture of long-span
denoising objectives, for planning and summarization. We empirically
demonstrate that our recipe improves the success on a real website by over 50%,
and that HTML-T5 is the best model to solve HTML-based tasks; achieving 14.9%
higher success rate than prior SoTA on the MiniWoB web navigation benchmark and
better accuracy on offline task planning evaluation.

基于大规模语言模型的 WebAgent 在网页导航任务中通过规划和总结 HTML 文档，以 Python 程序的形式实现自然语言指令，实验结果显示成功率提升了 50% 以上，并且 HTML-T5 模型在解决基于 HTML 的任务上表现最好。