Introduction to Prompt Engineering: The Art of Talking to AI

Prompt engineering is the skill of communicating effectively with AI models. It's the difference between mediocre responses and exceptional results.

Why Does It Matter?

The same model can give very different responses depending on how you ask:

Bad prompt:

Write about dogs

Good prompt:

Write a 100-word paragraph about the benefits 
of adopting adult dogs, targeted at families with children, 
in a warm and convincing tone.

Fundamental Techniques

1. Be Specific

The more context you give, the better the response will be.

• ❌ "Summarize this text"
• ✅ "Summarize this scientific article in 3 bullet points, highlighting methodology, results, and conclusions"

2. Define the Format

Indicate exactly how you want the response.

Respond in JSON format with the structure:
{
  "summary": "...",
  "key_points": ["...", "..."],
  "next_step": "..."
}

3. Use Examples (Few-shot)

Show what you expect:

Classify the sentiment of the text.

Example: "I loved the product" → Positive
Example: "It didn't work well" → Negative

Text: "It's acceptable, nothing special"

4. Assign a Role

You are an expert in computer security with 20 years 
of experience. Analyze this code looking for vulnerabilities.

5. Chain of Thought

Ask for step-by-step reasoning:

Solve this math problem.
Show your reasoning step by step before giving the final answer.

Advanced Techniques

Effective System Prompts

The system prompt defines the base behavior:

You are a concise code assistant. 
- Respond only with code when possible
- Use comments only if necessary
- Prefer simple solutions over complex ones
- If there's ambiguity, ask before assuming

Limitations and Constraints

Respond in a maximum of 50 words.
Don't use technical jargon.
If you don't know something, say "I don't have that information".

Common Mistakes

1. Prompts too vague: "Help me with my code"
2. Too much information: Noise that confuses the model
3. Not iterating: The first prompt is rarely the best
4. Ignoring context: Not taking advantage of the system prompt

Prompt Engineering and Costs

More efficient prompts = fewer tokens = less cost.

A well-designed prompt can:

• Reduce input tokens by 50%
• Get shorter and more precise responses
• Avoid retries due to incorrect responses

Conclusion

Prompt engineering is a skill that develops with practice. Experiment, iterate, and learn what works best for your specific use cases.

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