feat(instructions): add .instructions.md instructions (#309)

* feat(instructions): add `.instructions.md` instructions

* chore: update README

README.instructions.md

@@ -41,6 +41,7 @@ Team and project-specific instructions to enhance GitHub Copilot's behavior for
 | [Conventional Commit](instructions/conventional-commit.prompt.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fconventional-commit.prompt.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fconventional-commit.prompt.md) | Prompt and workflow for generating conventional commit messages using a structured XML format. Guides users to create standardized, descriptive commit messages in line with the Conventional Commits specification, including instructions, examples, and validation. |
 | [Convert Spring JPA project to Spring Data Cosmos](instructions/convert-jpa-to-spring-data-cosmos.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fconvert-jpa-to-spring-data-cosmos.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fconvert-jpa-to-spring-data-cosmos.instructions.md) | Step-by-step guide for converting Spring Boot JPA applications to use Azure Cosmos DB with Spring Data Cosmos |
 | [Copilot Process tracking Instructions](instructions/copilot-thought-logging.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fcopilot-thought-logging.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fcopilot-thought-logging.instructions.md) | See process Copilot is following where you can edit this to reshape the interaction or save when follow up may be needed |
+| [Custom Instructions File Guidelines](instructions/instructions.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Finstructions.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Finstructions.instructions.md) | Guidelines for creating high-quality custom instruction files for GitHub Copilot |
 | [Dart and Flutter](instructions/dart-n-flutter.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdart-n-flutter.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdart-n-flutter.instructions.md) | Instructions for writing Dart and Flutter code following the official recommendations. |
 | [DDD Systems & .NET Guidelines](instructions/dotnet-architecture-good-practices.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-architecture-good-practices.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdotnet-architecture-good-practices.instructions.md) | DDD and .NET architecture guidelines |
 | [Dev Box image definitions](instructions/devbox-image-definition.instructions.md)<br />[![Install in VS Code](https://img.shields.io/badge/VS_Code-Install-0098FF?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdevbox-image-definition.instructions.md)<br />[![Install in VS Code Insiders](https://img.shields.io/badge/VS_Code_Insiders-Install-24bfa5?style=flat-square&logo=visualstudiocode&logoColor=white)](https://aka.ms/awesome-copilot/install/instructions?url=vscode-insiders%3Achat-instructions%2Finstall%3Furl%3Dhttps%3A%2F%2Fraw.githubusercontent.com%2Fgithub%2Fawesome-copilot%2Fmain%2Finstructions%2Fdevbox-image-definition.instructions.md) | Authoring recommendations for creating YAML based image definition files for use with Microsoft Dev Box Team Customizations |

instructions/instructions.instructions.md

@@ -0,0 +1,256 @@
+---
+description: 'Guidelines for creating high-quality custom instruction files for GitHub Copilot'
+applyTo: '**/*.instructions.md'
+---
+
+# Custom Instructions File Guidelines
+
+Instructions for creating effective and maintainable custom instruction files that guide GitHub Copilot in generating domain-specific code and following project conventions.
+
+## Project Context
+
+- Target audience: Developers and GitHub Copilot working with domain-specific code
+- File format: Markdown with YAML frontmatter
+- File naming convention: lowercase with hyphens (e.g., `react-best-practices.instructions.md`)
+- Location: `.github/instructions/` directory
+- Purpose: Provide context-aware guidance for code generation, review, and documentation
+
+## Required Frontmatter
+
+Every instruction file must include YAML frontmatter with the following fields:
+
+```yaml
+---
+description: 'Brief description of the instruction purpose and scope'
+applyTo: 'glob pattern for target files (e.g., **/*.ts, **/*.py)'
+---
+```
+
+### Frontmatter Guidelines
+
+- **description**: Single-quoted string, 1-500 characters, clearly stating the purpose
+- **applyTo**: Glob pattern(s) specifying which files these instructions apply to
+  - Single pattern: `'**/*.ts'`
+  - Multiple patterns: `'**/*.ts, **/*.tsx, **/*.js'`
+  - Specific files: `'src/**/*.py'`
+  - All files: `'**'`
+
+## File Structure
+
+A well-structured instruction file should include the following sections:
+
+### 1. Title and Overview
+
+- Clear, descriptive title using `#` heading
+- Brief introduction explaining the purpose and scope
+- Optional: Project context section with key technologies and versions
+
+### 2. Core Sections
+
+Organize content into logical sections based on the domain:
+
+- **General Instructions**: High-level guidelines and principles
+- **Best Practices**: Recommended patterns and approaches
+- **Code Standards**: Naming conventions, formatting, style rules
+- **Architecture/Structure**: Project organization and design patterns
+- **Common Patterns**: Frequently used implementations
+- **Security**: Security considerations (if applicable)
+- **Performance**: Optimization guidelines (if applicable)
+- **Testing**: Testing standards and approaches (if applicable)
+
+### 3. Examples and Code Snippets
+
+Provide concrete examples with clear labels:
+
+```markdown
+### Good Example
+\`\`\`language
+// Recommended approach
+code example here
+\`\`\`
+
+### Bad Example
+\`\`\`language
+// Avoid this pattern
+code example here
+\`\`\`
+```
+
+### 4. Validation and Verification (Optional but Recommended)
+
+- Build commands to verify code
+- Linting and formatting tools
+- Testing requirements
+- Verification steps
+
+## Content Guidelines
+
+### Writing Style
+
+- Use clear, concise language
+- Write in imperative mood ("Use", "Implement", "Avoid")
+- Be specific and actionable
+- Avoid ambiguous terms like "should", "might", "possibly"
+- Use bullet points and lists for readability
+- Keep sections focused and scannable
+
+### Best Practices
+
+- **Be Specific**: Provide concrete examples rather than abstract concepts
+- **Show Why**: Explain the reasoning behind recommendations when it adds value
+- **Use Tables**: For comparing options, listing rules, or showing patterns
+- **Include Examples**: Real code snippets are more effective than descriptions
+- **Stay Current**: Reference current versions and best practices
+- **Link Resources**: Include official documentation and authoritative sources
+
+### Common Patterns to Include
+
+1. **Naming Conventions**: How to name variables, functions, classes, files
+2. **Code Organization**: File structure, module organization, import order
+3. **Error Handling**: Preferred error handling patterns
+4. **Dependencies**: How to manage and document dependencies
+5. **Comments and Documentation**: When and how to document code
+6. **Version Information**: Target language/framework versions
+
+## Patterns to Follow
+
+### Bullet Points and Lists
+
+```markdown
+## Security Best Practices
+
+- Always validate user input before processing
+- Use parameterized queries to prevent SQL injection
+- Store secrets in environment variables, never in code
+- Implement proper authentication and authorization
+- Enable HTTPS for all production endpoints
+```
+
+### Tables for Structured Information
+
+```markdown
+## Common Issues
+
+| Issue            | Solution            | Example                       |
+| ---------------- | ------------------- | ----------------------------- |
+| Magic numbers    | Use named constants | `const MAX_RETRIES = 3`       |
+| Deep nesting     | Extract functions   | Refactor nested if statements |
+| Hardcoded values | Use configuration   | Store API URLs in config      |
+```
+
+### Code Comparison
+
+```markdown
+### Good Example - Using TypeScript interfaces
+\`\`\`typescript
+interface User {
+  id: string;
+  name: string;
+  email: string;
+}
+
+function getUser(id: string): User {
+  // Implementation
+}
+\`\`\`
+
+### Bad Example - Using any type
+\`\`\`typescript
+function getUser(id: any): any {
+  // Loses type safety
+}
+\`\`\`
+```
+
+### Conditional Guidance
+
+```markdown
+## Framework Selection
+
+- **For small projects**: Use Minimal API approach
+- **For large projects**: Use controller-based architecture with clear separation
+- **For microservices**: Consider domain-driven design patterns
+```
+
+## Patterns to Avoid
+
+- **Overly verbose explanations**: Keep it concise and scannable
+- **Outdated information**: Always reference current versions and practices
+- **Ambiguous guidelines**: Be specific about what to do or avoid
+- **Missing examples**: Abstract rules without concrete code examples
+- **Contradictory advice**: Ensure consistency throughout the file
+- **Copy-paste from documentation**: Add value by distilling and contextualizing
+
+## Testing Your Instructions
+
+Before finalizing instruction files:
+
+1. **Test with Copilot**: Try the instructions with actual prompts in VS Code
+2. **Verify Examples**: Ensure code examples are correct and run without errors
+3. **Check Glob Patterns**: Confirm `applyTo` patterns match intended files
+
+## Example Structure
+
+Here's a minimal example structure for a new instruction file:
+
+```markdown
+---
+description: 'Brief description of purpose'
+applyTo: '**/*.ext'
+---
+
+# Technology Name Development
+
+Brief introduction and context.
+
+## General Instructions
+
+- High-level guideline 1
+- High-level guideline 2
+
+## Best Practices
+
+- Specific practice 1
+- Specific practice 2
+
+## Code Standards
+
+### Naming Conventions
+- Rule 1
+- Rule 2
+
+### File Organization
+- Structure 1
+- Structure 2
+
+## Common Patterns
+
+### Pattern 1
+Description and example
+
+\`\`\`language
+code example
+\`\`\`
+
+### Pattern 2
+Description and example
+
+## Validation
+
+- Build command: `command to verify`
+- Linting: `command to lint`
+- Testing: `command to test`
+```
+
+## Maintenance
+
+- Review instructions when dependencies or frameworks are updated
+- Update examples to reflect current best practices
+- Remove outdated patterns or deprecated features
+- Add new patterns as they emerge in the community
+- Keep glob patterns accurate as project structure evolves
+
+## Additional Resources
+
+- [Custom Instructions Documentation](https://code.visualstudio.com/docs/copilot/customization/custom-instructions)
+- [Awesome Copilot Instructions](https://github.com/github/awesome-copilot/tree/main/instructions)