It takes like 2 seconds in almost any language to do it too, just do it when you start your code, youll thank yourself later.

I even have a sort of template for shell scripts, if any arg will be on the commandline, it gets implemented.

For python (using argparse obviously), in my current project i built a toml file that handles the args. It allowed me to do more, like generating code blocks for js for the web frontend, documentation for both the cli and remote api, etc. Actually, now that I think about it, i might chunk that out to its own library.