The name of the memo is the command that comes after it:

  $ memo my-complex-command --some-flag my-positional-arg-1

In this invocation, a hash (sha512) is taken of "my-complex-command --some-flag my-positional-arg-1", which is then stored in /tmp/memo/${USER}/{sha512hash}.zst (if you've got zstd installed, other compression extensions otherwise).