While your concern is valid, I recommend learning about git hooks from their canonical source rather than from the documentation of any hook manager. Hooks are features of Git itself. Hook managers are an after-thought. Meanwhile, this tool and its docs also appear to be works in progress. I use pre-commit (a python program, not the hook itself) as a hook manager. But nothing beats the git book and docs. Here are some links:
1. https://git-scm.com/docs/githooks
2. https://git-scm.com/book/en/v2/Customizing-Git-Git-Hooks
Here is another site dedicated to git-hooks. You'll find some good examples and resources there:
https://githooks.com/