Nex Chrome Extension Pipeline

What it does

• Scaffolds the canonical MV3 layout from a one-line idea: manifest.json, background service worker, content script, popup (HTML, CSS, JS), options page, PRIVACY-POLICY.html, STORE-LISTING.txt, and icons at 16, 48, and 128 px generated with the included Pillow script.
• Classifies your idea into one of seven archetypes (overlay, scraper, autofill, side-panel-app, devtools, content-rewriter, action-on-click) and shapes files and permissions accordingly.
• Teaches the no-build dev loop: chrome://extensions, Load unpacked, edit and reload, with no npm install and no bundler.
• Covers the packaging pipeline: zip for the Chrome Web Store, crx for self-hosting, plus the store-listing checklist and permission justifications.
• Ships the real source of a shipped extension (nex-accent) in assets/reference/ as the working layout to copy from.

Why use this

Manifest V3 has enough sharp edges (stateless service workers, permission review, no remote code) that a first extension usually dies in setup. This pipeline encodes the vanilla JS plus HTML plus CSS pattern that shipped 23 extensions in production at Nex AI, so every decision from archetype to store submission is already made. The dev loop is edit, reload, test; a working extension is a day of work, not a week.

See it in action

Prompt:

I have an idea for a browser extension: one click saves the current tab's title and URL to my Notion. Where do I start?

Result:

Archetype: 7 (action-on-click). No popup needed.

nex-tab-to-notion/
  manifest.json        # permissions: activeTab, storage
  background.js        # chrome.action.onClicked -> Notion API call
  settings.html        # Notion API key + database ID
  settings.js          # stored in chrome.storage.sync
  icons/icon16.png icon48.png icon128.png
  PRIVACY-POLICY.html  # matches the manifest permissions
  STORE-LISTING.txt    # short description, single-purpose statement

Dev loop:
1. chrome://extensions -> Developer mode -> Load unpacked
2. Edit any file, click the reload arrow on the card
3. zip -r nex-tab-to-notion.zip nex-tab-to-notion/ and upload

Use cases

• Scaffold a new MV3 extension from scratch without a build step.
• Pick the right archetype and minimum-viable permissions for an idea.
• Package and submit an existing extension to the Chrome Web Store, with privacy policy and listing text.
• Run a rapid-ship cadence: one small extension per day.

Known limitations

• Chrome-first: Firefox and Safari extensions need different polyfills, tooling, and store flows.
• Manifest V3 only; it does not generate MV2.
• The vanilla no-build pattern is deliberate; if you want a framework popup, only the side-panel archetype includes a build-step migration recipe.

FAQ

What exactly is in the download?

SKILL.md, README.md, assets/reference/ with the full nex-accent source, five reference docs (the-seven-archetypes.md, manifest-v3-permissions.md, service-worker-lifecycle.md, store-submission-checklist.md, 21-extensions-cadence.md), manifest.json, CHANGELOG.md, and LICENSE.md.

Which agents does it work with?

Claude Code, Claude Cowork, Cursor, Codex CLI, and any agent that reads the SKILL.md format.

Do I need anything else?

Chrome with Developer mode, and Python with Pillow if you use the icon generator. A Chrome Web Store developer account only when you publish.

Does it help me choose permissions?

Yes. The archetype decides the permission set, and the skill enforces minimum-viable permissions (activeTab over <all_urls> where possible) with justifications ready for store review.