How We Built an AI-Powered Emoji List Generator with GitHub Copilot CLI

Introduction

Every week, the GitHub team hosts Rubber Duck Thursdays, a live stream where we build projects, cowork with our community, and answer burning questions. During a recent episode, we tackled a delightful yet practical challenge: creating an emoji list generator powered by AI. The goal was simple—speed up the tedious task of picking the perfect emoji for social media posts, product announcements, or any bullet list. Using the GitHub Copilot CLI, we built a fully functional terminal app in minutes. Here’s the story behind it, and how you can build something similar yourself.

What Is the Emoji List Generator?

You’ve likely seen tweets or launch posts that use emojis to highlight features, like:

• 💻 Works in the CLI
• 🧠 Uses AI to intelligently match emojis to your bullet points
• 📋 Copies the result to your clipboard

Coming up with those relevant emojis manually is slow—especially when you’re in a “move fast and break things” mindset. So we built a tool that automates it. The Emoji List Generator runs entirely in the terminal. You paste or type a list, hit Ctrl+S, and the app replaces each bullet point with a fitting emoji and copies the final text to your clipboard. No more hunting through emoji pickers!

How We Built It

The project came together quickly thanks to a few powerful technologies. Here’s a breakdown of the stack and the workflow we followed.

Choosing the Tech Stack

We relied on three main libraries:

• OpenTUI Core – for building the terminal user interface
• GitHub Copilot SDK – the AI engine that selects appropriate emojis
• Clipboardy – to easily copy the output to the system clipboard

These tools handled the UI, AI, and clipboard access, so we could focus on the application logic.

Using Plan Mode with Claude Sonnet 4.6

We started by opening the GitHub Copilot CLI in plan mode, using Claude Sonnet 4.6. We provided a simple prompt:

“I want to create an AI-powered markdown emoji list generator. In this CLI app, if I paste in or write some bullet points, it replaces them with relevant emojis and copies the result to my clipboard. Use the GitHub Copilot SDK for the AI.”

Copilot responded with a series of clarifying questions—about the tech stack, libraries, and expected behavior. With input from the chat (shoutout to Gabor for suggesting OpenTUI), we quickly had a fully thought-out plan.md file ready for review.

Implementing with Autopilot Mode

After approving the plan, we switched to autopilot mode using the freshly released Claude Opus 4.7. Within minutes, Copilot generated the complete code. We had a working terminal UI that accepted lists, called the Copilot SDK to generate emoji suggestions, and used Clipboardy to copy results. The whole process—from idea to working demo—took less than an hour.

Key Features and Tools

This project showcased several capabilities of the GitHub Copilot CLI:

• Plan mode – generated a detailed implementation plan through conversation
• Autopilot mode – automatically wrote the code based on the plan
• Multi-model workflow – used both Claude Sonnet 4.6 (planning) and Claude Opus 4.7 (coding)
• --allow-all-tools flag – enabled Copilot to execute commands and modify files as needed
• GitHub MCP server – allowed Copilot to interact with GitHub’s APIs during development

These features made the entire experience smooth and fast, letting us focus on creativity rather than boilerplate code.

Get Started Yourself

If you’d like to build a similar project, check out the official documentation for the GitHub Copilot CLI and the GitHub Copilot SDK. The Emoji List Generator itself is free and open source, so you can inspect, modify, or extend it as you like. Happy building!

Conclusion

The Emoji List Generator is a small but mighty example of what you can achieve with the GitHub Copilot CLI in a live-stream setting. By combining plan mode, autopilot, and a multi-model approach, we turned a fun idea into a practical tool in record time. Whether you’re a seasoned developer or just starting out, the Copilot CLI can accelerate your ideas—even when those ideas involve emojis.