GoogleChrome/modern-web-guidance-src

What this project is

Modern Web Guidance packages web platform expertise, best practices, and browser compatibility data into skills that coding agents can load. The goal is to stop agents from defaulting to legacy code, heavy polyfills, or large JavaScript bundles when a native platform feature already solves the problem. This repository is the source repository for the published skill; it holds the code and documentation used to author, calibrate, and evaluate the guide content See the project docs.

Content is organized into six areas: user experience, CSS layout, performance, forms and UI, accessibility, and built-in AI. The README lists 250 modern web features and 203 developer use cases, each mapped to a concrete guide. Authors from Chrome, Edge, Firefox, MDN, and the community steward it.

Quick start

The fastest way to see how it behaves is to search and retrieve a guide without installing anything:

npx modern-web-guidance@latest search "animate a dialog modal backdrop"
npx modern-web-guidance@latest retrieve "animate-to-from-top-layer"

To install the skill for your coding agent, run the interactive installer:

npx modern-web-guidance@latest install

The installer asks which skill packs to include; --choose lets you select them explicitly. Supported targets include the Vercel Skills CLI, GitHub CLI, Google Antigravity, GitHub Copilot CLI, Claude Code, Grok Build CLI, Kimi Code, and OpenAI Codex; the README lists the exact command for each Installation options. After installation, the agent finds the skill when a relevant web task comes up, runs a local semantic search, and pulls the matching guide into context. Updates use npx modern-web-guidance@latest update.

How the retrieval works

Search runs offline with an embedded model and a BM25 index, so it needs no network call or API key. Guides are designed to be token-efficient: content the models already know is pruned based on evaluations. Experimental Origin Trial APIs and volatile single-engine features stay discoverable through search but require explicit opt-in before retrieval, controlled via an optional .mwgrc file in the project root or ~/.mwgrc.

Known constraints

The CLI is distributed through npm and needs npx available on the machine. Telemetry is on by default and records installation counts, calling agent names, retrieved guide IDs, and search queries; raw user prompts are not collected. Set DISABLE_TELEMETRY=1 to opt out Telemetry details. The skill is not a substitute for the guides themselves: content covering experimental features may change, and the project uses a progressive-enhancement policy for fallbacks rather than blanket polyfills.

Licensing splits by content type: code uses Apache-2.0, and guide content under guides/ uses CC-BY 4.0.

HotRepo's take

On 2026-11-11 the repository reached 3rd place on the GitHub all-language daily ranking, gaining 133 stars that day. That is a single snapshot, so it supports the fact of a strong one-day surge rather than a trend. The more useful signal is the shape of the project: the README includes an evaluation dashboard and dated per-agent results (for example, Nov 8 runs reporting 54% → 82% for codex_cli and 58% → 94% for antigravity_cli on guided-versus-unguided tasks). Those numbers are the project's own harness output, not an independent benchmark, but they show that the repository treats guide quality as something to measure rather than assert.