# Modern Web Guidance

> Chrome-team skills that steer coding agents toward modern web platform features

- Category: Agents & Automation / Agent Skills & Plugins
- Licence: Apache-2.0
- Repository: https://github.com/GoogleChrome/modern-web-guidance
- Canonical page: https://ai-tldr.dev/tools/modern-web-guidance/
- Updated: 2026-11-10

## In short

Modern Web Guidance is a set of skills from the Chrome team, built with Edge, Firefox and MDN, that keeps coding agents from writing outdated web code. Models trained on years of older examples often reach for legacy JavaScript and CSS patterns even when the browser now has a built-in feature. It sits in the Agent Skills & Plugins category of the Agents & Automation tools and is open-source, licensed Apache-2.0.

## Overview

Modern Web Guidance is a set of skills from the Chrome team, built with Edge, Firefox and MDN, that keeps coding agents from writing outdated web code. Models trained on years of older examples often reach for legacy JavaScript and CSS patterns even when the browser now has a built-in feature. This project gives the agent current guidance and browser compatibility data to use instead.

Each skill tells the agent to call the modern-web-guidance CLI. The agent runs search, which matches its query to a guide locally with an offline embedding model and BM25 search, with no network calls or API keys. It then runs retrieve to load that guide's code patterns, gotchas and fallbacks into its context.

The guides cover 250 modern web features and 203 real-world developer use cases across CSS and layout, JavaScript and APIs, and HTML and DOM, plus accessibility, performance, forms and built-in browser AI. The README says the content is token-efficient, with material the models already know pruned out. A legacy-scan command also checks an existing codebase for outdated patterns. Version 1.0.0 was released on 10 November 2026.

## What it does

- Offline search and retrieval: guides are matched locally with embeddings and BM25, no API key needed
- 250 modern web features and 203 use cases, from CSS layout to built-in on-device AI
- legacy-scan command that flags legacy patterns in your project
- Token-efficient guides that leave out what models already know
- Install routes for the Vercel skills CLI, the GitHub CLI and Google Antigravity
- Apache-2.0 licensed

## Getting started

Installed through an npx wizard or the skills CLI; the CLI commands below are the ones the agent calls for you.

1. Run the installer

   The interactive wizard sets the skills up for your agent.

```bash
npx modern-web-guidance@latest install
```

2. Or install with the skills CLI

```bash
npx skills add GoogleChrome/modern-web-guidance
```

3. Try the CLI by hand

   Search for a guide, then retrieve it by its ID.

```bash
npx modern-web-guidance@latest search "animate a dialog modal backdrop"

npx modern-web-guidance@latest retrieve "animate-to-from-top-layer"
```

4. Scan an existing project

   legacy-scan reports legacy patterns in the current folder.

```bash
npx modern-web-guidance@latest legacy-scan .
```

## When to use it

- Stop an agent from writing 2019-style JavaScript when a native web feature exists
- Check an existing front-end codebase for legacy patterns with legacy-scan
- Give a team the same browser-compatibility guidance across several coding agents
- Get accessibility and performance patterns into agent-written UI code

## Version history

- 2026-11-10 v1.0.0: Modern Web Guidance reaches version 1.0.0, released the same day as the project's Show HN post.