How to Write Better Prompts: 7 Rules That Actually Work

Most weak AI outputs are not the model’s fault. They are the predictable result of vague, unstructured prompts. These seven rules fix the majority of prompt problems, regardless of which model you use.

1. Give the model a role

“You are a senior technical editor” outperforms no role at all because it anchors vocabulary, tone and standards. Keep roles specific: “a pediatric nutritionist” beats “an expert.”

2. Replace vague adjectives with measurable criteria

“Make it short and engaging” forces the model to guess. “Keep it under 120 words and open with a question” is checkable. Every time you write good, nice, some or etc., replace it with a number or a concrete example. Our Prompt Linter flags these words automatically.

3. Specify the output format explicitly

Models comply remarkably well with format instructions: “Respond as a Markdown table with columns X, Y, Z” or “Return only valid JSON matching this schema.” If you never state a format, you get whatever the model felt like.

4. Put instructions before content

State the task first, then provide the material, clearly delimited: “Summarize the text between the triple quotes.” Instructions buried below a long document get skipped more often.

5. One prompt, one job

Five questions in one prompt produce five shallow answers. Split complex work into a sequence of focused prompts, or at minimum use numbered steps so nothing is silently dropped.

6. Show, don’t just tell

A single input-output example (one-shot) often improves results more than a paragraph of description. Two or three examples are even better for formatting-sensitive tasks.

7. Keep prompts clean

Invisible characters, smart quotes and chaotic whitespace from copy-paste can subtly change tokenization and break templates. Run prompts through the Prompt Formatter before saving them, and expand rough ideas with the Prompt Expander so structure is never an afterthought.

Putting it together

Before: “Write something good about our new app, make it engaging etc.”

After: “You are a SaaS copywriter. Write a 100-word product announcement for our time-tracking app aimed at freelance designers. Tone: confident, no buzzwords. Format: one short paragraph followed by three bullet benefits.”

The second prompt takes thirty seconds longer to write and saves you five rounds of revision.