What would you like changed/added and why?

Static type-checkers, such as mypy, which analyse code at design time (i.e. before it runs), can be very useful in catching errors while you are writing. However, workflow construction in Pydra is currently too magic for them to be of much use and they tend to throw up lots of false positives. Given strong typing is a key feature of Pydra (particularly if #662 is accepted) it seems like it would be disappointing to users if this typing information isn't able to be utilised by static type-checkers like typical code.

While it won't be possible to get type-checkers to parse Pydra tasks/workflows as they are currently, I think we could get them to work with a few minor-ish adaptations along the lines of what I have already proposed in #655.

What would be the benefit?

Pydra workflows could be type-checked at design time, e.g. by editor-integrated linters, giving designers immediate feedback if they have attached the wrong outputs together or have format mismatches between tools they are linking.

I will expand on the changes I think would be necessary/sufficient in the comments below