gjson [1] and a few other go packages offer a way to parse arbitrary JSON without requiring structs to hold them.

re: Python. I like PyRight/PyLance for Python typing, it seems to "just work" afaict. I also like msgspec for dataclass like behavior [2].

---

1: https://github.com/tidwall/gjson

2: https://jcristharif.com/msgspec/