I have successfully created a custom action (tested it and can see the outputs - even renamed them), but for some reason, they are not appearing in the magic text.
In my case, the custom action is called “Get Token”.
I also tried doing it on another screen
Glad you got there so quickly yourself and I just wanted to follow up to say that this is the case. Custom actions attached as a screen action will not be accessible. Only custom actions linked to a button.