At https://docs.python.org/3/c-api/arg.html#numbers, it is explicitly documented that the unsigned number convertors do not perform overflow checking.  Implicitly, this suggests that the signed convertors *do* perform overflow checking, which they indeed do; but it would be nice to document this behavior explicitly (as overflow checking is not always expected of C-level functions).

This doesn't look a good idea to me. It is implied that all checks are performed. For example it is implied that an error will be raised if the argument is of wrong type. I think that adding "with overflow checking" to every converting from a Python integer will just clutter the documentation.

One could just add, immediately below the "Numbers" section, something like: "The signed convertors (b, h, i, ...) perform overflow checking.  The unsigned convertors (B, H, I, ...) do not."  That would actually be shorter than the current version, which repeats the second half for each unsigned entry...