Question about GGEP

Greetings everyone,

I am new to gnutella.  I have a question about GGEP.

The GGEP Specification does not say anything about about the format of
the GGEP Extension Data.  I understand this to mean that the GGEP
values are arbitrary raw bytes, whose interpretation is left to the
writers and readers of the particular GGEP key.

Is this an accurate statement?

If this is true, then what do we do about universally recognized GGEP
keys (GGEPs which are used by almost all servents) which are encoded
as Strings?  Is there a default (implied, standard) encoding (such as
UTF-8) that is used?

Thanks much,

David