prompt-engineeringlisted
Install: claude install-skill liujiarui0918/claude-code-codex-strongest
# Prompt Engineering — Write Prompts That Work
When the user asks you to help write or improve a prompt for an LLM, work from a structure. Don't just "polish" — diagnose what's missing and add it.
## Iron Law
**Test a prompt with at least 3 different inputs before declaring it done.** A prompt that works on one example is not a prompt; it's a coincidence. If you can't run the prompt, at least walk through it mentally with 3 inputs and predict the output.
## Anatomy of a Working Prompt
A good prompt has these elements, in roughly this order:
1. **Role / context** — who is the model acting as? What's the situation?
2. **Task** — what specifically should it do? One sentence.
3. **Constraints** — must / must-not. Brief, explicit.
4. **Examples** (few-shot) — 1-3 input → output pairs. Diverse.
5. **Output format** — concrete structure (XML / JSON / markdown / labeled sections).
6. **Evaluation criteria** (optional) — how to judge a good response.
Not every prompt needs all six. But missing more than two usually breaks it.
## Few-Shot vs Zero-Shot
- Zero-shot works for simple, well-known tasks ("translate this to French").
- Few-shot beats zero-shot for: domain-specific formats, unusual output structures, edge cases the model would otherwise miss.
- **3 examples is the sweet spot.** 1 example is risky (looks like an instance, not a pattern). 5+ has diminishing returns and bloats the prompt.
- Make examples **diverse**: different lengths, different edge cases, including one