AI product Open source · Apache-2.0
Modern Web Guidance is a set of skills and a CLI for coding agents, stewarded by the Google Chrome, Microsoft Edge, Mozilla Firefox, and MDN teams with the web development community. It embeds expert-curated web-platform guidance, browser compatibility data, implementation patterns, accessibility considerations, and fallbacks into an agent's context to steer code away from legacy patterns.
The CLI installs the skills with npx modern-web-guidance@latest install, searches guides locally with an offline zero-dependency embedding model and BM25 search engine, and retrieves guides by ID. It also provides a legacy-scan command for identifying older patterns in a codebase. The guidance covers modern CSS, HTML and DOM, JavaScript APIs, performance, accessibility, security, forms, UI components, WebAssembly, progressive web apps, built-in browser AI, and WebMCP. Origin Trial and volatile-feature guides are gated by project configuration, while the package operates locally without API keys or network calls during search and retrieval.
The repository is the source for the guidance and includes authoring, calibration, evaluation, contribution, and governance materials. It contains an automated evaluation harness using generated tasks, golden solutions, Playwright assertions, calibration loops, and guided versus unguided coding-agent comparisons. Software code is licensed under Apache License 2.0, while guide content under guides/ is licensed under CC BY 4.0. The CLI optionally collects anonymous usage information; the README documents DISABLE_TELEMETRY=1 as the opt-out.
1 use taken from transcripts — each links to the moment in the video.
Project from the Google Chrome team (supported by Microsoft Edge) that teaches AI coding agents to write modern web code via skills with best practices and browser compatibility data, plus a CLI for token-efficient guides.
1 in the library.