This repository is a living experiment in customizing GitHub Copilot using repository-level instructions, prompt files and chat modes. Each branch in this repo demonstrates a specific Copilot customization or instruction, with a clear purpose and practical example. The goal is not to follow a strict tutorial, but to let you explore the capabilities and benefits of Copilot customization by switching between branches and seeing the impact of each change in context.
The main branch is a clean starting point, providing only this overview and a breakdown of the Copilot instruction concepts. All other branches add a specific instruction, prompt or architectural pattern, so you can see how Copilot adapts and assists as the project evolves.
- Start on
mainto get the context and understand the motivation for customizing Copilot. - Fork this repository to your own GitHub account by clicking the "Fork on GitHub" button below or at the bottom of this README:
- Switch to any
part-*branch to see a focused experiment or instruction in action:- Each branch adds or refines a Copilot instruction, prompt file, or code pattern.
- Review the Copilot instructions, prompt files, and code changes in that branch.
- Try using Copilot Chat with the provided prompts and instructions to see how Copilot's suggestions and behavior change.
- There is no required order—jump to any branch that interests you and see the effect of that customization.
- main: The starting point. Contains only this overview and a breakdown of Copilot instruction concepts.
- part-one/add-copilot-instructions: Adds a
.github/copilot-instructions.mdfile to set workspace-wide Copilot behavior and preferences. - part-two/add-copilot-prompts: Introduces reusable prompt files (e.g., for code review, security checks) that can be invoked in Copilot Chat.
- part-three/add-pokemon-blazor-project: Adds a .NET Blazor project as a practical playground for Copilot customization.
- part-four/add-task-specific-instruction: Refines Copilot instructions to be more task-specific, guiding Copilot for particular coding tasks or workflows.
- part-five/add-pokemons-page: Implements a new Pokémons page in the Blazor app, using Copilot prompts and instructions to build a visually appealing gallery with PokeApiNet.
- part-six/add-service-refactor-instruction: Focuses on best practices for Blazor data services, refactoring prompts and instructions to encourage clean architecture and separation of concerns.
- part-seven/add-service-refactor: Implements the refactored services and updates Blazor components to use them, demonstrating Copilot's ability to assist with larger-scale refactoring guided by custom instructions.
Customizing Copilot at the repo level lets you:
- Set consistent coding style and workflow for your team or project.
- Create repeatable, task-specific Copilot chat commands with prompt files.
- Guide Copilot for real-world .NET/Blazor development, including UI, data fetching, and refactoring.
- See how Copilot responds to increasingly specific and complex instructions as your project grows.
GitHub Copilot can be tailored to your workflow and project needs. For a detailed overview of customization options, see:
This guide explains how to add repository-level instructions, create prompt files, and use chat modes to get the most out of Copilot in your development process.
Other resources:
- GitHub Docs – Adding Repo Instructions
- MCP Servers for agent mode
- Sample Chat Mode File by Burke Holland
- PokeApiNet - A .Net wrapper for the Pokemon API
Each branch is a snapshot of Copilot customization at a different stage, with practical examples and lessons learned. Switch between branches to explore and experiment!
