GitHub Copilot Setup in VS Code

Table of Contents

• Overview
• Instructions
  • 1. Install and Sign In
  • 2. Open the Correct Workspace Folder
  • 3. Verify Prompt File Detection
• Using Prompt Files
• Understanding the @ Syntax and # Context
• Related Documentation

Overview

This document describes how to install and configure GitHub Copilot for use in Graphitti.

Instructions

1. Install and Sign In

1. Open VS Code.
2. Go to the Extensions sidebar (Ctrl+Shift+X on Windows/Linux, Cmd+Shift+X on Mac).
3. Search for “GitHub Copilot Chat” and install it.
4. Ensure you are signed in with a GitHub account that has an active Copilot subscription (free tier, Pro, or through an organization).
   • How to check your login status: Look at the bottom-right corner of the VS Code Status Bar for the Copilot icon. If the icon is visible and doesn’t have a warning badge or a slash through it, you are actively logged in. You can also click the Accounts (profile gear) icon in the bottom-left corner to verify your active GitHub session.
   • How to log in manually: If you weren’t prompted to log in automatically upon installation, simply click the Accounts icon (bottom-left) or the Copilot icon (bottom-right) and select Sign in to use Copilot.

2. Open the Correct Workspace Folder

Prompt files are resolved relative to the workspace root — the folder you open in VS Code.

Important: You must open the repository root folder that directly contains the .github/prompts/ directory. For Graphitti, this means opening the folder that has .github/ as a direct child.

For example, if the repository is cloned to /home/user/Graphitti/, open the Graphitti folder in VS Code — not /home or /user. If VS Code’s Explorer sidebar shows .github/ as a top-level folder, you’re in the right place.

3. Verify Prompt File Detection

1. Open the Copilot Chat panel (Ctrl+Alt+I on Windows/Linux, Cmd+Ctrl+I on Mac).
2. Click the Configure Chat gear icon (⚙) at the top of the Chat panel.
3. Select Prompt Files from the menu.
4. You should see available prompt files (for example, generate-unit-tests and debug) listed. If they appear, setup is complete.

If it does not appear, confirm:

• The file is named with the .prompt.md extension (not just .md).
• The file is inside .github/prompts/ at the workspace root.
• You are on VS Code version 1.104 or later (prompt files are enabled by default in modern versions).

Using Prompt Files

You may run prompt files through multiple VS Code entry points listed below:

Method	How
Slash command	Type /command-name in the Chat input.
Command Palette	Ctrl+Shift+P (Win/Linux) or Cmd+Shift+P (Mac) → Chat: Run Prompt → select command-name.
Play button	Open command-name.prompt.md in the editor and click the ▶ play button in the editor title bar.
Configure Chat menu	Click ⚙ in the Chat view → Prompt Files → select the command-name prompt.

Understanding the @ Syntax and # Context

You may see references to @workspace or #codebase in Copilot documentation. Here is what they mean:

• @workspace — A built-in chat participant that gives Copilot knowledge of your entire project. When you type @workspace followed by a question, Copilot searches across all files in your workspace to answer it. Example: @workspace Where is the Graph class defined?
• @terminal — A chat participant for terminal-related questions. Example: @terminal How do I run the tests?
• @vscode — A chat participant for VS Code settings and features. Example: @vscode How do I change the font size?
• #codebase — A context tool that adds codebase search results to your prompt. Unlike @workspace (which handles the entire prompt), #codebase can be combined with other tools. It is the recommended approach for adding project-wide context.
• #file — Attaches a specific file as context. Example: #file:Vertex.h Explain this class.

You generally do not need to use @workspace or #codebase when running prompt files, because those prompts are already configured with tools that give Copilot automatic access to your codebase (the exact tools vary by prompt).

Related Documentation

• For shared prompt file anatomy and workflow layout, see Copilot Prompt Template Anatomy.
• For unit-test prompt details, see Copilot Prompt Templates: Unit Test Generation.
• For debug prompt details, see Copilot Prompt Templates: Debugging and Root Cause Analysis.