Advanced Prompting Techniques
Beyond basic prompting, several advanced techniques can dramatically improve LLM output quality, accuracy, and reliability.
Zero-Shot Prompting
Asking the model to perform a task without any examples:
Classify the sentiment of this review as Positive, Negative, or Neutral:
"The food was decent but the service was incredibly slow. Won't be returning."
Sentiment:Zero-shot works well for straightforward tasks where the model has seen similar patterns in training.
Few-Shot Prompting
Providing examples of the desired input-output pattern before asking the actual question:
Classify the sentiment:
Review: "Absolutely loved it! Best purchase ever."
Sentiment: Positive
Review: "It's okay, nothing special."
Sentiment: Neutral
Review: "Terrible quality, broke after one day."
Sentiment: Negative
Review: "The food was decent but the service was incredibly slow."
Sentiment:How Many Examples?
| Examples | Name | Best For |
|---|---|---|
| 0 | Zero-shot | Simple, well-defined tasks |
| 1-3 | Few-shot | Format and pattern matching |
| 4-8 | Many-shot | Complex classification, nuanced tasks |
Tips for few-shot examples:
- Use diverse, representative examples
- Cover edge cases
- Keep examples consistent in format
- Order can matter — put the most relevant examples last
Chain-of-Thought (CoT) Prompting
Ask the model to show its reasoning step by step. This dramatically improves accuracy on reasoning tasks.
Without CoT:
Q: A store has 15 apples. 8 are sold in the morning and 3 more arrive
in the afternoon. How many apples are there at the end of the day?
A: 10With CoT:
Q: A store has 15 apples. 8 are sold in the morning and 3 more arrive
in the afternoon. How many apples are there at the end of the day?
Think step by step:
A: Let me work through this:
1. Starting apples: 15
2. After morning sales: 15 - 8 = 7
3. After afternoon delivery: 7 + 3 = 10
The store has 10 apples at the end of the day.Simple CoT Trigger Phrases
- "Think step by step"
- "Let's work through this carefully"
- "Show your reasoning"
- "Break this down into steps"
Zero-Shot CoT
Simply adding "Let's think step by step" to any prompt:
"What is 17 × 23? Let's think step by step."
→ 17 × 23
= 17 × 20 + 17 × 3
= 340 + 51
= 391This single phrase improves math, logic, and reasoning tasks significantly.
Role Prompting
Assigning a specific persona or expertise to the model:
You are a senior security engineer at a FAANG company with 15 years
of experience in application security. You specialize in finding
vulnerabilities in web applications.
Review this authentication code and identify all security issues:
[code]Effective Role Prompts
| Role | Best For |
|---|---|
| "Expert in X" | Deep technical analysis |
| "Teacher explaining to beginners" | Simplified explanations |
| "Devil's advocate" | Finding counterarguments |
| "Code reviewer at Google" | High-quality code review |
| "Technical writer for API docs" | Documentation |
Self-Consistency
Generate multiple responses to the same prompt and take the majority answer. Useful for reasoning tasks where the model might err.
# Run the same prompt 5 times:
Prompt: "Is 17 a prime number? Think step by step."
Response 1: Yes (correct reasoning)
Response 2: Yes (correct reasoning)
Response 3: No (flawed reasoning) ← outlier
Response 4: Yes (correct reasoning)
Response 5: Yes (correct reasoning)
Majority vote: Yes ✓In practice, you can do this programmatically by setting temperature > 0 and calling the API multiple times.
Generated Knowledge Prompting
Ask the model to generate relevant knowledge before answering:
Step 1: Generate relevant facts about electric vehicles and
environmental impact.
Step 2: Using those facts, answer: "Are electric vehicles truly
better for the environment than gas cars?"This two-step approach produces more informed, nuanced responses.
Prompt Chaining
Breaking a complex task into a sequence of simpler prompts, where each output feeds into the next:
Prompt 1: "Extract all the key claims from this article"
→ [List of claims]
Prompt 2: "For each claim, identify what evidence would be needed
to verify it"
→ [Evidence requirements]
Prompt 3: "Rate each claim's credibility based on the evidence
requirements. Use: Verified / Likely / Uncertain / Unlikely"
→ [Final analysis]When to Chain vs Single Prompt
| Use Chaining | Use Single Prompt |
|---|---|
| Complex multi-step tasks | Simple, focused tasks |
| Need intermediate validation | One-shot generation |
| Each step requires different expertise | Consistent format needed |
| Output quality is critical | Speed matters more |
Negative Prompting
Telling the model what NOT to do:
Explain quantum computing to a high school student.
DO NOT:
- Use jargon without defining it
- Include mathematical formulas
- Make it longer than 200 words
- Use condescending language like "simply put" or "it's easy"ReAct (Reasoning + Acting)
Combining reasoning with actions in a structured format:
Question: What is the population of the capital of Australia?
Thought 1: I need to find the capital of Australia first.
Action 1: The capital of Australia is Canberra.
Thought 2: Now I need to find the population of Canberra.
Action 2: Canberra has a population of approximately 467,000.
Answer: The population of Canberra, the capital of Australia,
is approximately 467,000.This pattern is foundational for AI agents (covered in Module 7).
Comparison Table
| Technique | Best For | Complexity |
|---|---|---|
| Zero-shot | Simple tasks | Low |
| Few-shot | Pattern matching, classification | Low |
| Chain-of-thought | Math, logic, reasoning | Medium |
| Role prompting | Domain expertise | Low |
| Self-consistency | High-accuracy answers | Medium |
| Prompt chaining | Complex multi-step tasks | High |
| ReAct | Tasks requiring tools/actions | High |
Practice Exercises
- Use chain-of-thought to solve: "If a train travels at 60 mph for 2.5 hours, then 80 mph for 1.5 hours, what's the total distance?"
- Create a few-shot prompt to classify customer support tickets into categories
- Use role prompting to get a code review from different perspectives (security, performance, readability)
These techniques form the foundation for building reliable AI applications. The next topic covers reusable prompt patterns and frameworks.