Which comes first?
The answer should be obvious - tools. Many species of bird use tools, but don't appear to have languages as complex as ours (Appear being the strong word - I'm fairly sure they communicate more than we know).
The development of human language is a complicated thing, that probably had many different causes, but researchers have discovered that spreading complex toolmaking techniques is impossible without some kind of language. So, did humans invent language in order to teach each other to make knives?
It seems possible.
And can one envision a society and cognition in which only the toolmakers, the "smiths" use language?
Maybe...and it's worth considering that throughout Europe the smith is considered to be a magician...