Allow creation / publishing of Web Tool without setting default for a parameter

[Clubdebambos]

Currently when creating a custom Web Tool in ArcGIS Online via a Notebook you set a parameter and that parameter must have a default value or you cannot publish the tool for use (highlighted in image below - default should be optional, not required).

This is a bit ridiculous. I want users to be able to select a Point Feature Layer to feed into the tool not have one set for them and then they click run by accident on the default. 

Sure, make the parameter required. But a default required for every parameter is not a good user experience whatsoever. Default parameters should be options.

Cheers,

Glen