Cli exercism open

When I type

exercism open

then I got

Error: accepts 1 arg(s), received 0

was i type wrong command?
using mac with os 10.15.7 zsh

» exercism open --help
Open the specified exercise to the solution page on the Exercism website.

Pass the path to the directory that contains the solution you want to see on the website.

Usage:
   open [flags]

The usage doesn’t show that it expects an arg but the help string says you need to pass it a directory.

thank you my friend! have a good day!