Hey Prompt Warrior,

Today you’re getting a full guide on how to build a Chrome Extension using AI—from planning and coding to publishing it on the Chrome Web Store. 

And the best part is, you can do all of this without needing any programming experience at all.

But before we dive into it, why should you even care? In other words, why do I think Chrome extensions are a great thing to build? Several reasons:

1. They're relatively simple for beginners to tackle, yet powerful enough to build something genuinely useful and get it in front of lots of people.

2. Millions of people use the Chrome browser, so there's a huge market that you can tap into.

Here’s what we’ll cover in this post:

• How to come up with and plan your Chrome extension idea using AI

• How to write the code with the help of AI tools like Cursor

• How to publish your extension to the Chrome Web Store

Let's jump in!

Read time: 7 minutes

💡 Step 1: Planning your Chrome Extension

Every great extension starts with an idea.

Mine was simple: I'm often on X looking for content inspiration. What if I could select a tweet I like, and an AI could generate 10 new, similar tweet ideas tailored to my specific content themes and target audience? That’s the idea for the "Tweet Idea Remixer."

Before I start coding, I always want to do a quick planning session with AI to scope out my project and make sure I am not missing anything crucial.

1. Initial prompt:

"I want to build a [Chrome extension that lets me select a tweet, click the Chrome extension, and it will then generate 10 ideas similar to that tweet, based on the context of my content and audience that I have specified before]. 
Help me think about the essential MVP features for this extension to start with. Keep it really simple. Help me with any technical consideration I should know about. Keep in mind that I do not have any programming experience, so make it easy to understand."

(Replace the contents inside the square brackets [] with your own idea)

2. Refining the MVP Features: Claude (you can use ChatGPT too) then helped me nail down the these Minimum Viable Product (MVP) features:

• Tweet Selection: A way to grab the text of a tweet (e.g., right-click context menu or a browser toolbar button).

• Simplified User Profile: A basic settings page where I (the user) can input my content themes and target audience.

• Basic Idea Generator: The core AI magic – sending the tweet text and my profile info to Anthropic's API to get 10 new ideas.

• Simple Results Display: A clean pop-up to show the original tweet and the generated ideas.

• Minimal UI: Keep it simple to start.

The most important part is that you should start as simple as possible. If you start with too many and too complex requirements, you'll just end up building something that doesn't work.

3. Technical Considerations: Ideally, AI should take care of all the technical stuff for you. But it's still a good idea to let it lay out some of the things you need to know. This way, if you end up getting bugs, you will have a broad overview of the architecture and can fix things better.
   In this case, for example, you can ask it to help you explain the basic file structure for a Chrome extension (manifest.json, popup.html, content.js, background.js, etc.) and the general data flow.

Key Takeaway for Planning: This is an important step before you write a single (or prompt a single) line of code.

I mainly do it to:

• Get a better overview of the scope of my project

• Make sure I’m not missing anything important—especially on the technical side

• Build a context-rich chat that I can return to later while building, to ask follow-up questions as they come up

🔧 Step 2: AI-Powered Coding in Cursor

With a solid plan, it was time to build. For this, I used Cursor, still my AI code editor of choice.

Before we dive into the specifics, here’s a general approach that I always follow when building something like this. The key is to keep things iterative and build up complexity gradually:

• Start by building the simplest possible version that proves your core idea works.

• Once that's working, gradually introduce more complex functionality.

• Save UI refinement and polish for the final stage, after everything works reliably.

Here’s how I applied that approach in this specific example, broken down into four clear stages:

1. Start with the Core Functionality: The very first thing I built was a simple content extractor. I wanted the extension to grab the text of a tweet when I was on an X (Twitter) page. This meant creating a content script that could detect when I clicked the extension and then extract the tweet content from the page. It wasn’t perfect at first, so I used Cursor to iterate and fix bugs by feeding it real HTML and explaining what was going wrong.
   

   

2. Add the Main Feature: Once the basic text reading worked, I integrated the AI part. I used Cursor to write the code that would take the extracted tweet and send it to the Anthropic API. The response would be 10 new tweet ideas. At this point, I had the core functionality done: reading a tweet and remixing it with AI.

3. Add Supporting Functionality: After the main feature worked, I created a settings page. This let me input my content themes and target audience so the AI could generate better ideas. It also allowed users to save their Anthropic API key securely.

4. Refine the UI: Finally, I made everything look and feel good. I added loading indicators, cleaned up the design with help from v0.dev and Cursor, and made sure the popup displayed both the original tweet and the generated ideas clearly. This was the final layer—polishing things after all the logic worked.
   

   

This step-by-step layering kept the process clear and manageable. You shouldn’t do everything at once—just focus on one small piece at a time, then keep building on top of it. And make sure to save your project frequently (after every code change) by using Git!

🗒️ Step 3: Publishing to the Chrome Web Store

Once the extension was working and looking decent, it was time to publish it so other people could actually use it.

Here are the things you need to do to get your extension live on the Chrome Web Store:

1. Final Checks: Asked the AI to review everything for any issues and ensure all necessary permissions were correctly justified. Made sure no sensitive API keys were hardcoded.

2. Icons: Created some simple icons in Canva for various sizes (16x16, 48x48, 128x128).

3. ZIP It: Compress the entire extension folder into a ZIP file.

4. Chrome Developer Dashboard:
   

   

   • Navigate to developer.chrome.com/docs/webstore.

   • You'll need a Google Developer account (a one-time $5 fee).

   • Click "New Item" and uploaded the ZIP file.

5. Store Listing:

   • Description: I found a Chrome extension with a well-written description that matched the tone I wanted. Then I asked AI to rewrite it based on what my extension does and who it's for. This gave me a solid, benefit-focused description without starting from scratch.

   • Screenshots & Assets: Uploaded the icons and screenshots of the extension in action.

   • Privacy Policy: I quickly drafted one using AI, hosted it on a simple Notion page, and linked to it. It basically stated that the API key is stored locally and what data is sent to Anthropic.

   • Privacy Permissions: You’ll need to fill out justifications for the permissions your extension requests. For example, if your extension reads page content or uses local storage, Chrome wants to know why. I asked the AI in Cursor to draft these for me based on what my extension does.

6. Submit for Review: Hit submit! The review process usually takes a couple of days but it's not very difficult to pass. If there are issues, Google will let you know what to fix.
   

   

Key Takeaway for Publishing: The process is pretty straightforward. Just use AI for everything and you should have it done in about 1 hour.

🤖 TLDR:

If you’re looking to build something useful with AI but don’t know where to start, a Chrome extension is a great entry point. Here’s how to approach it:

1. Plan your idea and map out the basic functionality with AI

2. Build the extension step by step in Cursor, by starting from a simple feature and layering in more complexity.

3. Package and publish it to the Chrome Web Store so others can use it.

Follow this structure and you’ll go from idea to live product in less time than you think—no coding experience required.

Thanks for reading!

If you enjoyed this, consider forwarding this newsletter to a friend or colleague.

What would you like me to write about in the next post? Reply to this email and let me know.

Moritz

P.S. Want to go deeper and learn how to build software with AI?

That’s exactly what we do in the Prompt Warrior community.

You’ll find in-depth guides, step-by-step courses, ready-to-use templates, and live Q&A sessions where you can get direct feedback.