Question

tools used as nut crackers by chimps and birds

Answer 1

Parrots have nice tough beaks that were formed over time to crack tough nuts and insects. 

Chimps use rocks and other tools of their environment to crack tough stuff

Answer 2

Tools that monkeys and birds use to crack open nuts include: rocks/stones , logs, and I think this is more of a technique, but dropping the nut from a far enough height to where it breaks on impact