Antihydra is a small Turing machine with six states for which it's currently unknown if it will halt or not. It behaves similar to the Collatz sequences, and is a so-called cryptid. The full Python code is:

h = 8; c = 0
while c != -1:
    if h % 2 == 0:
        c += 2
    else:
        c -= 1
    h += h//2

This question will resolve as "yes" if a human is the first entity to provide a proof of whether Antihydra halts or not, and resolve as "no" if not (e.g. an AI system, an alien, a deity, or some other entity proves the halting behavior of Antihydra). The gold standard for resolution is a Lean proof, but other kinds of proofs are accepted if the mathematical community reaches consensus that it's a correct proof. If there's significant doubt by 2100, I'll resolve this question as ambiguous.

If Antihydra isn't proved by 2100, this question resolves as ambiguous.