How to Build a Chrome Extension Without Writing Code with AI Tools

A Chrome extension is a small add-on that changes how Chrome or a website behaves. AI tools can now write the code while you describe what you want.

• A button that summarizes the current page
• A word counter or reading timer
• An organizer for tabs or bookmarks
• A focus timer that blocks distracting sites
• A highlighter for keywords on any page

You supply the idea and the testing. AI supplies the code.

• Solves one problem you hit every day
• Runs on your own computer first
• Needs very few permissions
• Collects no personal data

Claude or ChatGPT

Chat-based: they write the files, and you copy them into a folder

Claude Code or Codex

Agent-based: they create the files in a folder for you and fix their own errors

Cursor or Grok Build

Other coding agents that work the same agent-based way

Beginners get on best with agent-based tools, since nothing needs copying by hand.

Build a Chrome extension with Manifest V3. What it does: [one sentence]. How it works: when I click the toolbar icon, [what happens]. Design: [simple, light colors, font]. Rules: request the fewest permissions possible, use no external servers and no tracking, and store settings only in Chrome storage. Give me every file, plus step-by-step instructions for loading it in Chrome.

manifest.json

Holds the extension’s name, version, and permissions. It must use Manifest V3.

popup.html

The small window that opens from the toolbar icon

Scripts

The code that does the actual work

Icons

Images for the toolbar and the store

You never have to write these yourself. Knowing what they are helps when the AI mentions them.

• Put every file in a single folder
• Open chrome://extensions
• Turn on Developer mode
• Click Load unpacked and select the folder
• Pin the extension and try it out

• Try every button and every setting
• Test it across several websites
• Paste any error from chrome://extensions back into the AI
• Request one change at a time
• Hit reload on the extension after every change

Here is the error, plus what I expected to happen. Fix only this problem and tell me which files you changed.

• Ask the AI to justify every permission
• Skip access to all websites unless the extension truly requires it
• Fewer permissions earn more trust and a quicker store review

• Collect no browsing history or personal data unless the extension requires it
• Keep API keys and passwords out of the code, since anyone can read it
• Have the AI scan the code for tracking or data sharing

• Register as a Chrome Web Store developer for a one-time $5 fee
• Zip the extension folder
• Add a description, screenshots, and icons
• Explain every permission and how you handle data
• Add a privacy policy if you handle any user data
• Submit it for review

Every extension must follow Chrome Web Store policies, including having one clear purpose. Check the latest rules before you submit.

• Starting with a large, complex idea
• Accepting every permission the AI proposes
• Skipping tests across different websites
• Copying the code or branding of other extensions