Dotnet Best Practices

--- name: dotnet-best-practices description: 'Ensure .NET/C# code meets best practices for the solution/project.' --- # .NET/C# Best Practices Your task is to ensure .NET/C# code in ${selection} meets the best practices specific to this solution/project. This includes: ## Documentation & Structure - Create comprehensive XML documentation comments for all public classes, interfaces, methods, and properties - Include parameter descriptions and return value descriptions in XML comments - Follow the established namespace structure: {Core|Console|App|Service}.{Feature} ## Design Patterns & Architecture - Use primary constructor syntax for dependency injection (e.g., `public class MyClass(IDependency dependency)`) - Implement the Command Handler pattern with generic base classes (e.g., `CommandHandler`) - Use interface segregation with clear naming conventions (prefix interfaces with 'I') - Follow the Factory pattern for complex object creation. ## Dependency Injection & Services - Use constructor dependency injection with null checks via ArgumentNullException - Register services with appropriate lifetimes (Singleton, Scoped, Transient) - Use Microsoft.Extensions.DependencyInjection patterns - Implement service interfaces for testability ## Resource Management & Localization - Use ResourceManager for localized messages and error strings - Separate LogMessages and ErrorMessages resource files - Access resources via `_resourceManager.GetString("MessageKey")` ## Async/Await Patterns - Use async/await for all I/O operations and long-running tasks - Return Task or Task from async methods - Use ConfigureAwait(false) where appropriate - Handle async exceptions properly ## Testing Standards - Use MSTest framework with FluentAssertions for assertions - Follow AAA pattern (Arrange, Act, Assert) - Use Moq for mocking dependencies - Test both success and failure scenarios - Include null parameter validation tests ## Configuration & Settings - Use strongly-typed configuration classes with data annotations - Implement validation attributes (Required, NotEmptyOrWhitespace) - Use IConfiguration binding for settings - Support appsettings.json configuration files ## Semantic Kernel & AI Integration - Use Microsoft.SemanticKernel for AI operations - Implement proper kernel configuration and service registration - Handle AI model settings (ChatCompletion, Embedding, etc.) - Use structured output patterns for reliable AI responses ## Error Handling & Logging - Use structured logging with Microsoft.Extensions.Logging - Include scoped logging with meaningful context - Throw specific exceptions with descriptive messages - Use try-catch blocks for expected failure scenarios ## Performance & Security - Use C# 12+ features and .NET 8 optimizations where applicable - Implement proper input validation and sanitization - Use parameterized queries for database operations - Follow secure coding practices for AI/ML operations ## Code Quality - Ensure SOLID principles compliance - Avoid code duplication through base classes and utilities - Use meaningful names that reflect domain concepts - Keep methods focused and cohesive - Implement proper disposal patterns for resources