`@code_warntype` and `Cthulhu.@descend` can both show `SomePackage.foo` was inferred as `Any`. But why? Cthulhu lets you immediately descend, and see that it's because it calls `SomeOtherPackage.bar`, so you descend, and see...
Five or ten calls in, you finally see a problem you can fix that can motivate a PR. This is fast to do with with `Cthulhu`. Descending is as easy as pressing `[enter]`, instead of requiring you to construct all the arguments and descend.
Exploring the call graph while doing this gives you some overview of what the code is doing, and you can always look for the initial cause of propagating instabilities, instead of wading through a ton of JET output (but JET is also great).
Is this built into the existing VSCode extension, or as another extension you need to install?
Update: I just saw that the last release is from 2023-08-31, so I guess it's been updating automatically.