Instructions — Examples for GitHub Copilot
Instructions tell GitHub Copilot how your project works. They provide context about your coding standards, architecture, and conventions so Copilot generates code that fits your project.
How instructions work
There are two types:
- Root instructions (
.github/copilot-instructions.md) — always active for every Copilot interaction in the repository - Scoped instructions (
.github/instructions/*.instructions.md) — activate only when Copilot is working with files that match a glob pattern defined in the file’s frontmatter
Scoping with glob patterns
Scoped instruction files use an applyTo frontmatter field to target specific files:
---
applyTo: "src/**/*.js"
---
This means the instruction only activates when Copilot is working on JavaScript files under src/. Use this to give stack-specific context without overloading every interaction.
How to use these examples
- Copy the instruction files into your repository’s
.github/and.github/instructions/directories - Edit the project overview in
copilot-instructions.mdto describe your service - Remove or modify instruction files that do not match your tech stack
- Add scoped instructions for any project-specific conventions not covered here
Available examples
| File | Scope | Purpose |
|---|---|---|
| copilot-instructions.md | All files | Project overview, branching, commits, quality gates |
| Node.js backend | *.js, *.mjs |
Hapi, vanilla JS, error handling, logging |
| Frontend | *.njk, *.html, *.css |
WCAG 2.2 AA, GDS Design System, Nunjucks, no JS frameworks |
| C# backend | *.cs, *.csproj |
ASP.NET Core Minimal APIs, Serilog, FluentValidation, xUnit |
| Python backend | **/*.py |
FastAPI, Pydantic Settings, async MongoDB, pytest |
| Documentation | **/*.md |
READMEs, ADRs, JSDoc, XML doc comments, inline comment discipline |
| Testing | **/*.test.js, **/*.test.mjs, **/test/** |
Jest, BDD naming, AAA pattern, coverage targets, mock discipline |
| Real-world example | — | Complete instructions file for a Node.js/Hapi/Nunjucks GOV.UK service |
Writing your own instructions
Follow this structure:
---
applyTo: "glob/pattern/**/*.ext"
---
# Topic Name
## Rules
- Concise, imperative rules
- One rule per line
- Include one example and one counterexample per rule where helpful
## References
- Links to canonical standards
Tips:
- Keep each file under 100 lines — Copilot processes shorter instructions more reliably
- One file per concern (backend, frontend, testing, documentation)
- Use imperative phrasing — “Use Hapi” not “Hapi should be used”
- Reference the Defra standards URLs so Copilot can cite them
