@TorkelE Is this metadata for XSystems? Or something else? not seeing any XSystems that have input and misc as fields

Sorry, symbolic metadata: https://docs.sciml.ai/ModelingToolkit/stable/basics/Variable_metadata/

Typically, a metadata md has two corresponding functions hasmd and getmd. But these metadata lacks them. basically you have to implement getmisc and getinput` so that

using ModelingToolkit
@parameters p [misc=["Random", :metadata]]
ModelingToolkit.getmisc(X)

works.

Check how similar functions are working. It can be worthwhile to see if you can find a list somewhere (and if there is not an exhaustive one, creating it) and checking that each one have both the hasX and getX functions.

As an example, it is using symbolic metadata that we e.g. have implemented the metadata tag telling us that a parameter is a conservation law parameter.

Added misc, though I think input is already there as isinput

The input field is just a Bool that says whether the variable is an input, I thought?

It seems like all of the boolean metadata variables just have isX as the getter (like input, output, irreducible). Is there a reason to write a separate getX?

To be honest, you are probably right. I was thinking of some system where it loops through metadata, but doesn't really make sense.