[nicexe]

I'm thinking if invalid characters in the examples given would be an acceptable solution. For DNS records this could be XML-like tags like <someprefix>.<yourdomain>.<tld>

On one hand, it prevents blind copy-pasting but on the other hand, your example is invalid.

[kevincox]

For procedure documentation I often use ${service_namr:?} For similar reasons. If the variable isn't set you get a clear error. And it provides an easy way to use the template without modification.

It isn't perfect, common variable names may already be set or have been set in a previous execution of this playbook on a different problem. But it catches common issues while being convenient.

[sanderjd]

Yeah I think this is the only good solution, really. Otherwise it's just often unclear which things are required to have a specific value, and which things can be replaced. In this example, I'm sure plenty of people thought it was possible that "someprefix" was required, rather than just an example.

[croes]

An invalid example could confuse the customer and create unnecessary support calls.