GitHub Copilot CLI Expert

Comprehensive knowledge of GitHub Copilot CLI installation, configuration, usage, and extensibility.

Purpose

This skill provides expert guidance on:

• Installing and updating GitHub Copilot CLI

• Authentication and configuration

• Core usage patterns and slash commands

• Extensibility (MCP servers, skills, custom agents)

• Troubleshooting common issues

When I Activate

Automatically when you mention:

• "copilot cli", "github copilot cli", "gh copilot"

• "install copilot", "update copilot"

• "copilot commands", "copilot slash commands"

• "copilot mcp", "add mcp server"

• "copilot skills", "create copilot skill"

• "copilot custom agent"

Quick Reference

Installation (All Platforms)

Always fetch latest version - use these commands:

Platform Command

Windows (WinGet) winget install GitHub.Copilot

macOS/Linux (Homebrew) brew install copilot-cli

All (npm, Node.js 22+) npm install -g @github/copilot

macOS/Linux (Script) curl -fsSL https://gh.io/copilot-install | bash

Prerelease versions: Add @prerelease or use GitHub.Copilot.Prerelease

Authentication

copilot # Launch and follow /login prompt

OR use PAT with "Copilot Requests" permission:

export GH_TOKEN=your_token

Essential Slash Commands

Command Purpose

/help

Show all commands and shortcuts

/model

Select AI model (Claude Sonnet 4.5, GPT-5, etc.)

/agent

Browse and select available agents

/skills

Manage skills

/mcp

Manage MCP server configuration

/delegate [prompt]

Hand off to Copilot coding agent (creates PR)

/compact

Reduce context window usage

/context

Show token usage visualization

Keyboard Shortcuts

Shortcut Action

@

Mention files to include in context

!

Execute shell command directly

Esc

Cancel current operation

Ctrl+C

Cancel / clear / exit

Ctrl+L

Clear screen

Ctrl+O

Expand/collapse timeline

Extensibility Overview

• MCP Servers - Extend Copilot with external tools

• Skills - Task-specific instructions and scripts

• Custom Agents - Specialized agent profiles

• Custom Instructions - Repository-wide guidance

Navigation Guide

When to Read Supporting Files

reference.md - Read when you need:

• Complete slash command reference with all options

• Detailed MCP server configuration and JSON schema

• Full permissions system documentation

• Advanced configuration options

• Environment variables reference

examples.md - Read when you need:

• Step-by-step installation walkthroughs

• Working MCP server configurations

• Skill creation examples

• Custom agent examples

• Real-world usage scenarios

Core Concepts

MCP Servers (Model Context Protocol)

Copilot CLI includes GitHub MCP server by default. Add custom MCP servers:

/mcp add # Interactive configuration /mcp show # List configured servers /mcp edit <name> # Modify existing server

Config stored in: ~/.copilot/mcp-config.json

Skills

Skills enhance Copilot's task performance with instructions and scripts.

Locations:

• Project: .github/skills/ or .claude/skills/

• Personal: ~/.copilot/skills/ or ~/.claude/skills/

Structure:

.github/skills/my-skill/ └── SKILL.md # Instructions with YAML frontmatter

Custom Agents

Specialized agent profiles stored as Markdown files.

Locations:

• User: ~/.copilot/agents/

• Repository: .github/agents/

• Organization: .github-private/agents/

Custom Instructions

Repository-specific guidance for Copilot:

• .github/copilot-instructions.md

• Repository-wide

• .github/instructions/**/*.instructions.md

• Path-specific

• AGENTS.md

• Agent behavior instructions

Troubleshooting Quick Tips

Issue Solution

Not installed brew install copilot-cli or npm i -g @github/copilot

Not authenticated Run /login in Copilot CLI

Policy disabled Check org/enterprise Copilot settings

MCP server not loading Verify ~/.copilot/mcp-config.json syntax

Skill not activating Restart Copilot CLI, check SKILL.md YAML

Version: 1.0.0 | Status: Public Preview Note: GitHub Copilot CLI is in public preview and subject to change.