Prompts 2026: 7 Mistakes That Kill Quality + Perfect-Request Checklist

We’ve covered prompt structure, the persona pattern, and working with long texts. Now – a practical checklist and the typical mistakes that drag down the quality of AI answers.

Checklist: before you hit send

Structure (non-negotiable)

• Role – who is answering? (not “an expert,” but “a senior marketer in e-commerce”)
• Context – what’s the situation? (what’s already known, what’s the goal)
• Task – a concrete action verb (write, shorten, analyze)
• Constraints – what NOT to do (no more than X words, no emoji, no apologies)
• Format – what should the answer look like (table, list, JSON)

Positioning (for long prompts)

• Key instructions – at the beginning and at the end
• Raw data – in the middle
• For prompts of 10,000+ tokens – anchor reminders every 5–10 thousand
• For very long tasks – break it into a chain of shorter prompts

Final check

• Is the prompt understandable to a person who doesn’t know the context?
• Are there any conflicting instructions?
• Are there concrete success metrics? (“cut by 50%” instead of “cut it down”)

7 anti-patterns: what kills quality

1. Vague instructions

❌ “Make the text better”

✅ “Cut by 30%, remove filler openers, add concrete numbers”

Why: AI doesn’t know what “better” means to you. For some people it’s brevity, for others it’s detail.

2. Excessive politeness

❌ “Please, if it’s not too much trouble, could you possibly try to…”

✅ “Shorten the text. Format: 3 paragraphs”

Why: Extra words dilute the instruction. AI is trained to answer politeness with politeness – you’ll get fluff.

3. No negative constraints

❌ “Write a business email”

✅ “Write a business email. DO NOT use: ‘I would like to note,’ ‘allow me to inform you,’ apologies without cause”

Why: Models default to “polite” boilerplate. Without explicit bans, you’ll get it.

4. Names instead of functions

❌ “You are Elon Musk”

✅ “You are an entrepreneur applying first principles thinking”

Why: The model imitates the celebrity’s style, not the methodology. You get bravado instead of logic.

5. Conflicting roles

❌ “You are a creative marketer and a strict accountant”

✅ “Create a campaign. Then switch to the CFO role and evaluate ROI”

Why: Contradictory values average out the result. Better – sequential roles.

6. Critical information in the middle

❌ A long prompt with the budget constraint buried on page 3

✅ Budget – in the first 100 words + repeated in the final instruction

Why: The “Lost in the Middle” effect – AI handles the middle of long texts worst.

7. One prompt to rule them all

❌ 50 resumes + 10 criteria + analysis in a single prompt

✅ 5 prompts of 10 resumes each with intermediate conclusions

Why: A chain of short prompts is more accurate than one long one. You control every step.

Quick wins: what to roll out today

1. A template for recurring tasks

Build a template for repeat requests. Fill in only the variables:

# ROLE
You are [role with experience]

# CONTEXT
[What's known, what's the situation]

# TASK
[Concrete verb] + [object]

# CONSTRAINTS
- DO NOT [constraint 1]
- DO NOT [constraint 2]
- Maximum [X] words/items

# OUTPUT FORMAT
[Table / List / Structure]

2. Few-Shot for tricky formatting

If you need a specific format – show 2–3 examples:

Input: "Customer complains about slow delivery"
Output: { "type": "logistics", "urgency": "high", "action": "contact within 24h" }

Input: "Question about warranty"
Output: { "type": "legal", "urgency": "low", "action": "forward to support" }

Input: [your text]
Output:

3. The “start + end” rule

Key instructions – always in the first 200 words and the last 100.

Wrapping up the series

Across 4 articles we’ve covered:

1. Prompt structure – 5 elements: role, context, task, constraints, format
2. Persona – why the role works, and how to phrase it in 2025
3. Prompt size – the “Lost in the Middle” effect and techniques for long texts
4. Practice – the checklist and anti-patterns (this article)

That’s the foundation. From here – practice and experiments with your own specific tasks.

Next step

Theory without practice is useless. At mysummit.school/prompts you can:

• Try every technique from this series in interactive mode
• Compare results from different models (ChatGPT, Claude, Gemini)
• Get feedback on your own prompts