I just found the algorithm tag, our most-used tag without a tag wiki (excerpt).
It has 16 questions (7 asked in the last 30 days), and I can't seem to find what this tag indicates (for writing it into a tag wiki).
Most questions on Crypto.SE are about some algorithm, this is not really specific here. The questions here are of these types:
What algorithm can I use to do X? (convert between elliptic curve operations, generate prime numbers (another one), find discrete logarithms, factorize large integers, calculate primitive roots, decrypt only after some time, sign the current time)
I need some detail about algorithm X (RSA)
What algorithms are used in X? (PGP)
For what algorithms I need/can use X? ("real" random numbers)
Looking at the numbers, only retaining type 1 would be worth to consider (then we could look if there are more questions of this type not yet tagged). But even this is dubious: Would there be people following this tag (for now, 0 followers), or searching questions about "is there some algorithm which does something", no matter what?
So, my proposal is to remove this tag completely (without replacement).