Building an emoji list generator with the GitHub Copilot CLI

Cassidy Williams describes building an AI-powered emoji list generator during GitHub’s Rubber Duck Thursdays livestream. The terminal application converts bullet points into relevant emojis, then copies the formatted Markdown list to the clipboard with a keyboard shortcut. The project demonstrates how GitHub Copilot CLI and SDK can quickly turn a small idea into a functional open-source tool.

The Emoji List Generator

• Runs directly in the terminal.
• Accepts pasted or typed bullet points.
• Uses AI to replace each bullet with a relevant emoji.
• Generates the result when the user presses Ctrl + S.
• Copies the completed list to the clipboard.
• Exits with Ctrl + C.

Technologies Used

• @opentui/core provides the terminal user interface.
• @github/copilot-sdk supplies the AI functionality.
• clipboardy handles clipboard access.

Building the Project with Copilot CLI

• Development began in Copilot CLI’s plan mode using Claude Sonnet 4.6.
• A natural-language prompt described the desired Markdown emoji generator and requested integration with the Copilot SDK.
• Copilot asked clarifying questions about the technology stack and libraries.
• It then produced a plan.md file for review.
• The implementation was completed with Claude Opus 4.7 only a few minutes later.

Copilot CLI Features Demonstrated

The livestream project combined several Copilot CLI capabilities:

• Plan mode for outlining the implementation.
• Autopilot mode for carrying out development tasks.
• A multi-model workflow using different Claude models.
• The allow-all tools flag for permissive tool access.
• The GitHub MCP server for GitHub-related integrations.

The finished Emoji List Generator is available as a free, open-source project, alongside documentation for the GitHub Copilot CLI and SDK.