What problem does it solve? .NET applications often fail at runtime due to misconfiguration such as missing connection strings, invalid URLs, or out-of-range values, with errors surfacing deep in business logic far from where configuration is loaded. This Skill provides patterns to bind configuration to strongly-typed classes and validate it at application startup, so invalid settings fail fast with clear error messages. ## Core Features & Use Cases - Options Binding: Bind appsettings.json sections to POCO settings classes and consume them via IOptions<T>, IOptionsSnapshot<T>, or IOptionsMonitor<T>. - Startup Validation: Apply Data Annotations validation and custom IValidateOptions<T> validators with ValidateOnStart() to catch misconfiguration immediately. - Advanced Scenarios: Handle named options for multiple instances, validators with injected dependencies like IHostEnvironment, post-configuration, and live configuration reload in background services. - Use Case: When building an ASP.NET Core service that connects to SMTP, databases, or Akka.NET clusters, use this Skill to define settings classes, register validators, and guarantee the app refuses to start with invalid configuration. ## Quick Start Ask the AI to set up a strongly-typed SmtpSettings configuration class with startup validation using IValidateOptions in your .NET project.
