Let’s say you customized your Zsh prompt by editing ~/.zshenv

#customize prompt:
PROMPT=$'[%n@%m][H:%B%!%b][J:%B%j%b]> '

You should see something like this:

[root@bigbadunixbox][H:2487][J:0]>

If you want to see all 2487 lines of your Zsh history buffer do this:

history 1 | less