Interactive Thing discovery (ideas)

Hello! This topic comes out of the second question asked in Shared configuration and custom thing add process regarding customizing Thing scan process. I’d like this topic to become a brainstorming area on the best possible implementation.
So, short recap: a scan requres the user to enter a One-time-password, somehow provided by the hardware.
Of course it’s possible to implement some special kind of a Thing to assist the scan, but i think having to add this Thing , which does not even have a physical representation, does not feel intuitive from user’s perspective. So i am seeking to extend the OpenHab discovery interface.
I see there is already a manual scan functionality. This is good because it fits our scenario. We only need to parametrize it.
The first question is: during manual scan there is an empty screen in the Inbox with a spinner and “Scan in progress” message. Is there currently a way for the binding to do some custom output there, like discovery log?
I am thinking about leveraging this into adding parameters (OTP in my case) entry and “Go” button. Yes, i know, core mod is required for that.