Prompt Engineering Basics: Structure Beats Cleverness

1. Say what “done” looks like#

Models are much better at hitting a target you’ve described than at guessing one. Instead of “summarize this,” say “summarize this in 3 bullet points, each under 20 words, focused on decisions made rather than discussion.” The output format is part of the task, not an afterthought.

2. Give it the constraints you’d give a person#

If a colleague would need to know a constraint to do the task right — a deadline, an audience, a length limit, a thing to avoid — the model needs it too. “Don’t use marketing language” is a more useful instruction than “make it good.”

3. Show, don’t just tell, when the format matters#

If you want a specific output shape (a particular JSON structure, a specific tone), one example is often worth several sentences of description. This is few-shot prompting, and it’s the single highest-leverage technique for format-sensitive tasks.

4. Separate instructions from content clearly#

Use headers, delimiters, or XML-ish tags to mark where your instructions end and the content to work on begins:

1
Summarize the text between the tags below.
2

3
<text>
4
{{content}}
5
</text>

This prevents the model from confusing instructions in the content with instructions from you — especially important once your prompts get long or the content is user-supplied.

5. Ask for the harder thing directly#

“List the 3 most important risks” beats “tell me about risks” — models default to the safe, generic answer unless you ask for the specific, opinionated one. If you want judgment, ask for judgment explicitly.

What doesn’t matter as much as people think#

Politeness (“please”, “thank you”) has negligible effect on output quality. Elaborate role-play personas (“You are a world-renowned expert with 30 years of experience…”) help less than a clear task description with real constraints. Spend your effort on structure, not framing.

Every prompt in the Prompts library on this site follows these five habits — worth a look for concrete examples of the structure in practice.