No bash, posso usar o helpcomando para imprimir uma sinopse para um comando interno específico
$ help pwd
pwd: pwd [-LP]
Print the name of the current working directory.
Options:
-L print the value of $PWD if it names the current working
directory
-P print the physical directory, without any symbolic links
By default, `pwd' behaves as if `-L' were specified.
Exit Status:
Returns 0 unless an invalid option is given or the current directory
cannot be read.
Existe um equivalente em zsh ou apenas uso man zshbuiltins?