example of a custom script for Kate

Hi

First of all - thank you great text editor Kate.
Recently I started looking on how to add a simple command to format JSON,
and tried to follow the blogpost from 2009 [1].
However it did not work for me.

Perhaps you have a Github example of how-to a simple custom command would
look like?
Afterall, I probably don't need a long blog post - just a source code to
peek into.

Sincerely,
Dan

[1]
https://kate-editor.org/2009/10/29/extending-kate-with-scripts/