Modern Web Guidance, a set of skills that feeds web platform best practices and browser compatibility data into AI coding agents, is now available on GitHub under the GoogleChrome organization. According to its README, the project is stewarded by the Google Chrome, Microsoft Edge, Mozilla Firefox and MDN teams together with the web development community, and its stated aim is to steer agents away from legacy patterns and toward the capabilities of the modern web platform.
The project installs with a single command, npx modern-web-guidance@latest install, which runs an interactive wizard. It also ships plugin and skill packages for Claude Code, OpenAI Codex, GitHub Copilot CLI, Google Antigravity, Cursor, Grok Build CLI and Kimi Code, and can be added through the Vercel Skills CLI or the GitHub CLI. Agents use a search command to find a relevant guide and a retrieve command to load its code patterns, gotchas and fallbacks. The README says search runs locally using an offline embedding model and BM25, with no network calls, and a legacy-scan command checks an existing codebase for outdated patterns.
The guides cover roughly 250 web platform features, split into CSS and layout, HTML and DOM, and JavaScript and APIs, across areas including accessibility, performance, forms, security and passkeys, built-in AI and WebMCP. A second skill pack covers Chrome extension development with Manifest V3. The maintainers say the guides are designed to be token-efficient. The code is released under the Apache 2.0 license, and the project collects anonymous usage telemetry that can be disabled with DISABLE_TELEMETRY=1.
The repository publishes an evaluation dashboard. Its snapshot for November 2 to 8 shows pass rates rising by roughly 27 to 36 percentage points when Claude Code, Codex CLI and Antigravity CLI used the guidance compared with running unguided. These figures come from the project's own evaluations.
For teams using coding agents on front-end work, the project offers a maintained, browser-vendor-backed reference that agents can query instead of relying on patterns from older training data. Optional flags in a .mwgrc file allow guidance on origin trials and features that are still changing. Source: GoogleChrome/modern-web-guidance on GitHub.