Microsoft’s .NET team has introduced a way for developers to embed “custom instructions” files in their repositories, enabling AI to adapt to project-specific workflows, code conventions, and review guidelines . Released six days ago, the update lets teams centralize their preferences—such as naming patterns, error‑handling styles, and preferred frameworks—within a simple markdown file. This ensures Copilot Chat starts each interaction already primed with the right context for the project.

Here’s how to do it:

Step 1: Create a .github folder at the root of your solution.
Step 2: Add a copilot-instructions.md file inside that folder.
Step 3: Write your custom instructions in Markdown (there’s a great community repo for inspiration).
Step 4: Open GitHub Copilot in Agent mode, load your project, and ask away!

Once Agent mode runs, Copilot uses your instructions to tailor its responses. Give it a try and take control of your AI assistant.