Copilot customization cheat sheet
Compare the different customization options for GitHub Copilot.
In this article
Section titled “In this article”- Feature overview
- Usage comparison
- IDE and surface support
- Agent Customizations editor in JetBrains IDEs
- Further reading
GitHub Copilot offers several customization features that let you tailor its behavior to your workflow, your team’s standards, and your project’s needs. Use the tables below to find the right one for your use case.
Feature overview
Section titled “Feature overview”This table shows what each customization feature is and where it lives.
| Feature | What it is | Filename and location |
|---|---|---|
| Custom instructions | Always-on context that automatically applies to every interaction within its defined scope | .github/copilot-instructions.md (repo-wide), .github/instructions/*.instructions.md (path-specific), AGENTS.md (third-party agents), or personal/org settings via UI on GitHub |
| Prompt files | Reusable, standalone prompt template with input variables | .github/prompts/*.prompt.md |
| Custom agents | Specialist persona with its own instructions, tool restrictions, and context | .github/agents/AGENT-NAME.md (repository), /agents/AGENT-NAME.md in the organization’s .github or .github-private repository (org-level), /agents/AGENT-NAME.md in a designated .github-private repository (enterprise-level), or user profile |
| Subagents | Separate agent spawned by the main agent to handle delegated work in an isolated context | N/A (runtime process, not a user-configured file) |
| Agent skills | Folder of instructions, scripts, and resources that Copilot loads when relevant to a task | .github/skills/<skill-name>/SKILL.md, .claude/skills/<skill-name>/SKILL.md, or .agents/skills/<skill-name>/SKILL.md (project); ~/.copilot/skills/<skill-name>/SKILL.md or ~/.agents/skills/<skill-name>/SKILL.md (personal) |
| Hooks | Custom shell commands that execute deterministically at specific points in an agent’s workflow | .github/hooks/*.json |
| MCP servers | Connection to external systems, APIs, and databases | mcp.json (path varies by IDE), repository MCP settings on GitHub (applies to cloud agent and Copilot code review), or mcp-servers property in custom agent configurations |
Usage comparison
Section titled “Usage comparison”This table helps you decide which customization feature to use.
| Feature | How to trigger | Best for | Example use cases |
|---|---|---|---|
| Custom instructions | Automatic | Standards, guidelines, or expectations that apply broadly across a context | Enforce coding standards, accessibility rules, review checklists |
| Prompt files | Manual: reference directly in chat or use the prompt file picker | Focused single tasks you run once with different inputs each time | Generate unit tests, run a code review checklist |
| Custom agents | Manual: select from the agent dropdown in your IDE, on GitHub, or in Copilot CLI | Projects or processes with distinct stages that need specialized capabilities or strict handoffs | React reviewer agent, read-only auditing agent |
| Subagents | Automatic, or reference a subagent directly in your prompt | Complex subtasks that should run in isolation from the main agent | Codebase research, running test suites |
| Agent skills | Automatic: chosen by Copilot when relevant to your prompt | Multi-step workflows with bundled assets that should be loaded as needed | GitHub Actions failure debugging, deployment procedures, release note drafting |
| Hooks | Automatic: at configured lifecycle events | Tasks that need to run at a specific point in the agent lifecycle, with guaranteed execution | Run a formatter after every file edit, approve or deny tool executions, prevent credential leaks with secret scanning |
| MCP servers | Automatic, or ask for a specific tool by name | Tasks that require access to external tools or real-time data | Manage issues and PRs (GitHub MCP server), automate browser testing (Playwright MCP server) |
IDE and surface support
Section titled “IDE and surface support”This table shows which customization features are supported in each IDE and surface. For the full Copilot feature matrix, see Copilot feature matrix.
GitHub recommends using the latest stable IDE, Copilot CLI, and Copilot extension versions to get the best Copilot experience.
Key:
- ✓ = supported
- ✗ = not supported
- P = under preview
| Feature | VS Code | Visual Studio | JetBrains IDEs | Eclipse | Xcode | GitHub.com | Copilot CLI |
|---|---|---|---|---|---|---|---|
| Custom instructions | ✓ | ✓ | P | P | P | ✓ | ✓ |
| Prompt files | ✓ | ✓ | P | ✗ | P | ✗ | ✗ |
| Custom agents | ✓ | ✓ | P | P | P | ✓ | ✓ |
| Subagents | ✓ | ✗ | P | P | P | ✗ | ✓ |
| Agent skills | ✓ | ✓ | P | ✗ | ✗ | ✓ | ✓ |
| Hooks | P | ✗ | ✗ | ✗ | ✗ | ✓ | ✓ |
| MCP servers | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
For a detailed breakdown of which types of custom instructions are supported in each IDE and surface, see Support for different types of custom instructions.
Agent Customizations editor in JetBrains IDEs
Section titled “Agent Customizations editor in JetBrains IDEs”In JetBrains IDEs, you can use the Agent Customizations editor to manage multiple Copilot customizations from one place. In the GitHub Copilot Chat panel, click the settings icon in the top-right, then click Customizations.
From the editor, you can:
- View and edit custom agents
- Manage reusable skills
- Configure workspace or personal instructions
- Manage prompt files
- Choose Workspace customizations for the current project or Personal customizations that follow you across projects
For steps to create repository instructions and prompt files in JetBrains IDEs, see Adding repository custom instructions for GitHub Copilot in your IDE.
Further reading
Section titled “Further reading”- Customization library — a curated collection of examples