The line is in your discovery function.
These are no params but the data you get.
I think you mix here something. Parameters are only things like a state you want to remember at discovery time, like the interface has the status “up” at discovery time.
Then your check can see if the state changes.
What is missing in your code is your parsing section.
This conversation should be done by the parse function and not inside the discovery function.
What will also be important is how does your section looks like before any parsing happens.
The header of the section is here the relevant part.