@Marvin Is it expected that

foo_flow = flow(foo, name="foo")

triggers a

mypy

error?

No overload variant of "flow" matches argument types "Callable[[str, str, str, str | None, bool, str | None, str, int, str | None, int, int, bool, str], str]", "str"mypy

for

mypy 1.10.0

&

prefect 2.19.1

This is a barrier to creating flows from existing entrypoints (which I don't want to decorate) because mypy cant infer types.

Yes, it seems your experience with the

mypy

error when using

flow

in Prefect is consistent with other reported issues. There are several user-submitted tickets highlighting

mypy

compatibility issues with Prefect flows and tasks, and these issues are known within the community. ### Issues 1. Error with mypy when using async (#9898) 2. mypy fails to infer return types of Tasks (#7408) The mismatch stems from `mypy`'s ability to infer the types correctly when working with Prefect’s decorators and method signatures, especially when it comes to asynchronous tasks and their return types. ### Potential Workarounds - Using

pyright

: Some users have found that

pyright

infers types correctly where

mypy

fails. You might consider switching to

pyright

for type checking. - Manual Type Annotations: Explicitly annotate your return types and try breaking down complex function signatures to help

mypy

infer types better. ### Links - Issue #13856 - Issue #9898 - Issue #7408 Regrettably, dealing with type inference issues is not particularly thrilling, but remember, you aren't alone in facing these challenges. Perhaps one day, life will grant us compatibility across all tools—though I wouldn't hold my breath.