Get output in an exact format

I need output in this format: {{format}}
For this task: {{task}}

Write the prompt. Show the format by example rather than describing it — a
one-instance sample constrains far harder than a prose specification. State what to
do when a field has no value, because that is where format compliance usually
breaks.

Then say what to do if the output still drifts, in order of what to try first.

What to fill in

{{format}}

The format you need — e.g. JSON with keys id, title, tags

{{task}}

The task — e.g. classify each support ticket