Google has released a set of Modern Web Guidance guides for coding agents

The Google Chrome team has released version 1.0 of the Modern Web Guidance set of guides. The project was created in collaboration with Firefox, MDN, and Edge to teach AI agents modern web standards instead of outdated JavaScript patterns.

The release includes 200+ guides totaling about 1.7 MB, containing web development best practices. The tool includes a CLI utility with RAG-based search weighing ~7 MB, which runs at a speed of ~10 ms on a CPU, as well as a built-in legacy code scanner with 92% accuracy.

According to the company's internal tests on 200 tasks and 1,700 Playwright/AST assertions, applying the guides increases the success rate of frontend tasks performed by coding agents from 55% to 92%.

The tool is open source. A detailed breakdown of the release is published on the official Google Developers blog.