name: creating-instructions description: Create custom instruction files (.instructions.md) to guide Copilot. Use when enforcing coding styles, defining architectural patterns, or establishing project-specific standards.

Creating Custom Instructions

Name: creating-instructions
Rating: 88
Author: kamontat

File Format

•Extension: .instructions.md
•Location: .github/instructions/ (or .github/copilot/instructions/ depending on config).

Frontmatter

yaml

---
description: Brief description of what this instruction covers.
applyTo: '**/*.ts' # Glob pattern
---

Body

The body contains the instructions.

•
Be Specific: "Use const" is better than "Use modern JS".
•
Show Examples:
typescript
```
// Bad
var x = 1

// Good
const x = 1
```

Best Practices

•Scoped: Use applyTo to limit instructions to relevant files.
•Concise: Copilot has a context window. Don't waste it.
•Updated: Keep instructions in sync with project evolution.

Example

markdown

---
description: Ensure all components use Svelte 5 runes.
applyTo: 'src/components/**/*.svelte'
---

# Svelte 5 Rules

1. Use `$state` instead of `writable`.
2. Use `$props` instead of `export let`.