Does something like this make sense?

```csharp
/// <summary>
/// Specifies a function used to help produce a <see cref="Task{T}"/> return value when the configured call is made.
/// The function will be called each time this call is made and can return different values
/// each time. Each time the call is made, the function's return value will be used as the <see cref="Task.Value"/>
/// of a completed Task.
/// </summary>
/// <typeparam name="T">The type the Task returns.</typeparam>
/// <param name="configuration">The configuration to extend.</param>
/// <param name="valueProducer">A function that produces the Task's return value.</param>
/// <returns>A configuration object.</returns>
```