I think types are particularly valuable for libraries. A library author using copious types really helps the downstream user to know "Ok, this function returns a dict(Foo, Bar)". But after that, it's a matter of preference if you want to add those types to your own code or not.
Having the types in the libraries makes it a lot easier for your tools/IDEs to give good suggestions and catch bugs that you might otherwise miss.
I think types are particularly valuable for libraries. A library author using copious types really helps the downstream user to know "Ok, this function returns a dict(Foo, Bar)". But after that, it's a matter of preference if you want to add those types to your own code or not.
Having the types in the libraries makes it a lot easier for your tools/IDEs to give good suggestions and catch bugs that you might otherwise miss.