Minimal APIs are the recommended approach for building fast HTTP APIs with ASP.NET Core. They allow you to build fully functioning REST endpoints with minimal code and configuration. You don't need a controller but can just declare your API using a fluent API approach: This makes it very convenient to build your APIs. However you need to be aware that a lot of magic is going behind the scenes when using this approach. And this magic can bite you in the foot. Exactly what happened to me while building an autonomous agent invoked through a web hook. The code In my application I created the following API endpoint using the minimal API approach: The minimal API injects an AzureDevOpsWebhookParser that looks like this: Nothing special… The problem The problem was when I called this endpoint, it failed with the following error message: InvalidOperationException: TryParse method found on AzureDevOpsWebhookParser with incorrect format. Must be a static method with for...