Introduction to Prompt Engineering
Prompt engineering is the practice of designing inputs to get desired outputs from LLMs. Good prompts dramatically improve result quality and consistency.
Basic Techniques
1. Zero-Shot Prompting
Direct instruction without examples:
Classify the sentiment of this text as positive, negative, or neutral:
Text: "The product exceeded my expectations"
Sentiment:2. Few-Shot Prompting
Provide examples to guide the model:
Classify the sentiment:
Text: "Amazing quality!" → Positive
Text: "Terrible experience" → Negative
Text: "It's okay" → Neutral
Text: "Best purchase ever" →3. Chain-of-Thought (CoT)
Ask the model to show reasoning:
Q: A store has 50 apples. They sell 20 and buy 15 more. How many?
A: Let's think step by step.
- Start: 50 apples
- Sell 20: 50 - 20 = 30
- Buy 15: 30 + 15 = 45
Final answer: 45Advanced Patterns
System Prompts
Set the model’s role and behavior:
system_prompt = """You are an expert code reviewer.
Focus on: security, performance, and maintainability.
Be concise and actionable."""Structured Output
Request specific format:
Analyze this text and return JSON:
{
"sentiment": "positive|negative|neutral",
"confidence": 0.0-1.0,
"key_phrases": ["phrase1", "phrase2"]
}Self-Consistency
Generate multiple answers and vote:
answers = [llm.invoke(prompt) for _ in range(5)]
final_answer = most_common(answers)Best Practices
| Practice | Description |
|---|---|
| Be Specific | Clear instructions produce better results |
| Use Delimiters | Separate instructions, context, and input |
| Specify Format | Tell the model how to structure output |
| Add Constraints | Set boundaries (length, tone, style) |
| Iterate | Test and refine prompts |
🛠 Key Tools
| Tool | Purpose | Link |
|---|---|---|
| LangChain | Prompt Management | Details |
| PromptLayer | Version Control | Details |
| OpenAI Playground | Testing | Details |
FAQ
Q1: What is the most important prompt engineering principle?
Be specific and clear. Vague prompts produce inconsistent results.
Q2: When should I use few-shot prompting?
Use when you need consistent output format or specific reasoning style.
Q3: What is Chain-of-Thought prompting?
A technique to improve reasoning by asking the model to show step-by-step thinking.
Summary
Effective prompt engineering requires clarity, examples, and iteration. Start with simple techniques and add complexity as needed.





