ASP.NET Core Web API Best Practices

When to Use

• Creating new controllers, minimal API endpoints, or feature folders in an ASP.NET Core project
• Configuring the middleware pipeline, routing, or model binding
• Adding authentication, authorization policies, or [Authorize]-based access control
• Implementing error handling with ProblemDetails (RFC 9457) or IExceptionHandler
• Wiring up OpenAPI/Swagger, health checks, CORS, rate limiting, output caching, or response compression
• Writing in-memory integration tests for endpoints via WebApplicationFactory (Microsoft.AspNetCore.Mvc.Testing)
• Reviewing or restructuring an existing ASP.NET Core project to align with best practices

This skill covers the HTTP / web layer only. For dependency injection, Options pattern, and configuration that apply to any .NET host, see dotnet-fundamentals.

Core Principles