PlugWiki

chrome-extensions Skill for Claude Code: Build and Publish Chrome Extensions

Teaches Claude to build Manifest V3 Chrome extensions without the common breakages, and to prepare them for Chrome Web Store review.

Installs
11.8K
on skills.sh
Stars
2.6K
on GitHub
Files
23
besides SKILL.md
Updated
Oct 2026
last repo commit

chrome-extensions has two parts. Part 1 gives Claude 20 mandatory rules for Manifest V3, such as never storing state in service worker variables, providing a way to open a side panel, running code only in sandboxed frames, and using async/await. Part 2 covers publishing: Claude keeps a CHROMEWEBSTORE.md file with store copy, permission justifications, privacy disclosures and version history, and checks a pre-publish list.

It triggers on Chrome extension work and Web Store requests. The SKILL.md points to 23 reference files, which Claude reads before writing code. The folder holds 24 Markdown files and no scripts, though the references include a packaging shell script and an icon generator in Python.

Good for

  • Developers building or fixing a Chrome extension
  • Makers preparing a Chrome Web Store listing and permission justifications
  • Anyone whose extension breaks on service workers, side panels or CSP

Install chrome-extensions

Claude Code

  1. 1

    Copy this prompt.

    Install the chrome-extensions skill in Claude Code. Run this command:

/plugin marketplace add GoogleChrome/modern-web-guidance
/plugin install modern-web-guidance@googlechrome
/reload-plugins

Then check that it loaded and tell me how to use it.
  2. 2

    Paste it into Claude Code. It shows the change and asks before running it.

Pick one route. The plugin and the skills CLI take the repo as a whole (its skills folder holds two skills); the wizard with --choose lets you take chrome-extensions only. The README suggests enabling AutoUpdate for the marketplace in /plugin.

From the project README. Source.

What's in the skill

When it loads

Build and publish Chrome Extensions using Manifest V3 best practices. Use this skill whenever the user asks to create, modify, debug, or understand Chrome browser extensions, add-ons, or anything involving the Chrome Extensions API. Trigger on mentions of: 'Chrome extension', 'browser extension', 'manifest.json', 'content script', 'service worker' (in browser context), 'popup' (in browser extension context), 'side panel', 'chrome.* API', 'declarativeNetRequest', 'omnibox', 'context menu' (in extension context), 'userScripts', 'user script', 'script manager', or any request to build functionality that integrates with the Chrome browser UI. Also trigger for publishing to the Chrome Web Store: 'publish extension', preparing an extension for publishing, responding to a review rejection, writing permission justifications, or drafting a privacy policy.

Sections in SKILL.md

  1. Part 1 — Building Extensions
  2. Mandatory Rules
  3. Always Manifest V3
  4. Part 2 — Publishing to the Chrome Web Store
  5. Core Workflow
  6. How to fill it out
  7. CHROMEWEBSTORE.md Sections
  8. Pre-Publish Checklist
  9. Store Listing Copy Guidelines
  10. Reference Files
  11. Output Checklist

Key facts

Author
Google Chrome
Repo
googlechrome/modern-web-guidance
License
Apache-2.0
Installs on skills.sh
11,751 (Nov 2, 2026)
GitHub stars
2,593 (Nov 2, 2026), whole repo
Last commit
Oct 26, 2026 (repo)
Files in the skill folder
24 files including SKILL.md
Part of
Modern Web Guidance, a preview release with 2 skill packs
Works in
Claude Code, Codex, Cursor, Windsurf, GitHub Copilot CLI and others via plugins or the skills CLI

What it includes

  • Rules that prevent broken extensions, from icons to permissions.

    Examples: no state in service worker variables, sandboxed code execution, no chrome.windows.query.

    Mandatory rules (20)

  • Never generates Manifest V2 code.

    Use background.service_worker, chrome.action and chrome.scripting.executeScript.

    Always Manifest V3

  • 19 files for permissions, side panels, content scripts, storage, devtools and more.

    Claude reads the relevant file before writing code.

    Extension reference files

  • A single file with store listing, permission justifications and version history.

    Claude creates it when you mention publishing and updates it on changes.

    Write · CHROMEWEBSTORE.md

  • Writes a plain-English reason for each permission and host permission.

    The SKILL.md calls it the highest-risk section; vague reasons get rejected.

    Permissions justification

  • Helps draft a privacy policy that matches your data use.

    From references/webstore/privacy-policy.md.

    Privacy policy guidance

  • Checks the common first-submission failures.

    For instance a live privacy URL and screenshots at 1280x800 or 640x400.

    Pre-publish checklist

  • Specific, benefit-led descriptions without implementation details.

    Includes a table of what to cut and what to keep.

    Store listing copy

  • A shell script that zips the extension without .git, node_modules or .env.

    In the review checklist reference. It deletes the old zip first.

    Runs code · Packaging script

  • A Python Pillow script that writes icon-16, icon-48 and icon-128 PNG files.

    In the icons reference. The SKILL.md also allows omitting icons.

    Runs code · Icon generator

  • 29 checks to pass before Claude hands work back.

    From manifest_version 3 to the Chrome M150+ rule for the "tab" context in context menus.

    Output checklist

From the official docs

Permissions

Low risk

The skill's references include a packaging script that deletes and rebuilds a zip, and an icon script that writes files. The README says Google collects anonymous usage information from the tool; set DISABLE_TELEMETRY=1 to opt out.

What it can do

  • Read your data
  • Create and change things
  • Delete things
  • Read-only mode

Watch out for

  • It can write and delete files in your project

    The packaging script runs rm -f on the old zip and then zip -r with an exclude list. Check the output name and exclude list before running it. github.com

  • Google collects usage data from the tool

    The README's Telemetry & Privacy section says Google collects anonymous usage information: installation counts, the calling agent name, guide retrieval IDs and CLI search queries generated by the agent, but not raw prompts. Set DISABLE_TELEMETRY=1 to opt out. github.com

  • The installer runs an npm package

    The quick start is npx modern-web-guidance@latest install, which runs a wizard from npm. The README says the package has no extra dependencies. github.com

Technical details
Scopes

  • Writes CHROMEWEBSTORE.md, icon files and a zip in your project if you ask

Questions

What does chrome-extensions do?

It makes Claude follow Manifest V3 rules when building a Chrome extension, so it avoids common breakage. It also helps prepare a Chrome Web Store submission with permission justifications, a privacy policy and a store listing.

How do I install it?

Use the install box above. The README's installer, npx modern-web-guidance@latest install --choose, lets you pick the chrome-extensions pack. The Claude Code plugin installs the whole repo.

Does it need an API key?

No key is mentioned. The icon and packaging examples need Python with Pillow and a zip tool if you run them.

Does it work in Claude.ai, Codex or Cursor?

The README documents plugins for Claude Code, Codex, GitHub Copilot CLI and others, and the skills CLI. It does not describe the Claude app, but the skill is plain Markdown.

Is it safe?

The skill bundles no scripts. Its references show a packaging script that runs rm and zip, and a Python icon script, which Claude may run if you ask. The README's Telemetry & Privacy section says Google collects anonymous usage information: installation counts, the calling agent name, guide retrieval IDs and CLI search queries generated by the agent, but not raw prompts. Set DISABLE_TELEMETRY=1 to opt out.

Does it send my data anywhere?

The README's Telemetry & Privacy section says Google collects anonymous usage information: installation counts, the calling agent name, guide retrieval IDs and CLI search queries generated by the agent, but not raw prompts. Set DISABLE_TELEMETRY=1 to opt out. The README does not say which commands report, and the chrome-extensions SKILL.md itself names no CLI commands.

chrome-extensions vs modern-web-guidance?

They are two skill packs in the same repo. chrome-extensions covers extensions and the Web Store. The other covers modern browser APIs, layout and performance, and chrome-extensions sends general Prompt API questions to it.

Information

updated Nov 2, 2026

Repository
googlechrome/modern-web-guidance
Folder
skills/chrome-extensions

googlechrome/modern-web-guidanceskills.sh

Sources

Docs, issue trackers and discussions this page is built from.

Show all 5
  1. modern-web-guidance README · github.com
  2. chrome-extensions SKILL.md · github.com
  3. LICENSE · github.com
  4. review-checklist.md · github.com
  5. icons.md · github.com

Updated Nov 2, 2026.