> I honestly think Raw provides too little information. What is a Raw?

You may prefer `RawBytes`?

> String at least reminds of C++, Golangs, Java's, ... string types, which are often Pascal-type strings, like this one is.

Yeah, but in C you have to treat it not like a string (in the usual C definition of string) but as a raw sequence of bytes. We not only have a struct with a length in it, we also allow `\0` bytes in it, thus all `str*` should be avoided.

> Fwiw, I find the msgpack terminology confusing. But they probably did that to make sure nobody thought you could feed C strings to that interface.

One confusing terminology is better than a confusing terminology + a different terminology.