Prompt.Lab
Practical prompt guide

Bad prompt.
Better direction.

A vague idea forces an AI to guess. These before-and-after examples show how a little context, structure, and a clear finish line can make the answer far more useful.

Compare the examples ↓
01 / WritingBefore → after

Bad prompt

Write an email about our meeting.

The AI has to invent the missing audience, purpose, boundaries, and output.

Better prompt

Act as a clear and professional business writer. Write a concise follow-up email to a prospective client after our first meeting. Thank them for their time, summarize the two agreed next steps, and propose a 30-minute call next week. Keep the tone warm and confident, use fewer than 160 words, and end with a specific call to action.

+ Audience and purpose+ Tone and length+ Concrete next action
02 / LearningBefore → after

Bad prompt

Explain photosynthesis.

The AI has to invent the missing audience, purpose, boundaries, and output.

Better prompt

Act as a patient biology tutor. Explain photosynthesis to a 15-year-old student who understands basic cell structure but finds chemistry difficult. Start with a simple real-world analogy, explain the process in five numbered steps, define the essential terms, and finish with three short questions that check understanding. Use clear English and avoid unnecessary jargon.

+ Learner level+ Teaching method+ Comprehension check
03 / CodingBefore → after

Bad prompt

Fix my JavaScript.

The AI has to invent the missing audience, purpose, boundaries, and output.

Better prompt

Act as a senior JavaScript developer. Review the code I provide, identify the root cause of the error, and explain it in plain language before showing the correction. Preserve the existing behavior and coding style unless a change is necessary. Return: 1) the diagnosis, 2) the corrected code, and 3) two brief tests that demonstrate the fix. Do not invent missing dependencies; ask one focused question if essential context is unavailable.

+ Diagnostic role+ Preserved constraints+ Verifiable output
04 / MarketingBefore → after

Bad prompt

Make an Instagram post for my product.

The AI has to invent the missing audience, purpose, boundaries, and output.

Better prompt

Act as a social media strategist for a small productivity software brand. Write an Instagram carousel concept that introduces a new focus timer to university students. Create a strong first-slide hook, five short educational slides, and a final call to action. Keep each slide under 18 words, use an energetic but credible tone, and provide a caption without exaggerated claims. The objective is to encourage free trials, not immediate purchases.

+ Defined audience+ Platform-ready format+ Honest conversion goal
05 / PlanningBefore → after

Bad prompt

Make me a workout plan.

The AI has to invent the missing audience, purpose, boundaries, and output.

Better prompt

Act as a general fitness planning assistant. Create a four-week beginner exercise schedule for an adult who can train at home three times per week for 30 minutes and has access to resistance bands. Prioritize consistency and gradual progression. Present each session in a table with exercise, sets, repetitions, and rest. Include warm-up and recovery guidance, avoid medical claims, and clearly recommend professional advice if pain or health concerns are present.

+ Available time and equipment+ Progression rules+ Safety boundaries
06 / Creative workBefore → after

Bad prompt

Give me ideas for a video.

The AI has to invent the missing audience, purpose, boundaries, and output.

Better prompt

Act as a short-form video creative director. Generate eight original 20–30 second video concepts for a beginner-friendly AI education account. Each concept must teach one practical idea, open with a curiosity-driven hook, work without expensive equipment, and end with a natural invitation to save or share the video. Present the concepts in a table with hook, visual action, lesson, and closing line. Avoid fear-based or misleading claims about AI.

+ Channel positioning+ Production limits+ Repeatable structure

The pattern

Four details that make prompts easier to follow.

01

Give the AI a useful role

Choose relevant expertise instead of adding a decorative persona.

02

State the real objective

Describe the outcome, audience, and reason the answer will be used.

03

Protect what matters

Add limits, preferences, facts to preserve, and things the AI must avoid.

04

Define the finished output

Specify the format, depth, language, and what a complete answer includes.

Your idea is next

Keep the idea.
Remove the guesswork.

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