# ContainerRuntimeArgsCallbackAnnotation Properties

- Package: [Aspire.Hosting](/reference/api/csharp/aspire.hosting.md)
- Type: [ContainerRuntimeArgsCallbackAnnotation](/reference/api/csharp/aspire.hosting/containerruntimeargscallbackannotation.md)
- Kind: `Properties`
- Members: `1`

Represents an additional argument to pass to the container runtime run command.

## Callback

- Name: `Callback`
- Modifiers: `get`
- Returns: `Func<ContainerRuntimeArgsCallbackContext, Task>`
- Source: [GitHub](https://github.com/microsoft/aspire/blob/bd20f904cde09ecb9c9ae5116a6f13614bf2d7c2/src/Aspire.Hosting/ApplicationModel/ContainerRuntimeArgsCallbackAnnotation.cs#L43)

Gets the callback action to be executed when the executable arguments are parsed.

```csharp
public Func<ContainerRuntimeArgsCallbackContext, Task> Callback { get; }
```