This one handles the full lifecycle of LLM prompt design, from writing your first zero-shot attempt to building evaluation frameworks that catch regressions. It walks you through the workflow (understand, design, test, iterate, deploy) and loads reference docs for specific patterns like chain-of-thought or structured outputs. The validation checkpoint at 80% accuracy is a nice forcing function to stop and diagnose failures before you keep tweaking randomly. What I appreciate is the before/after examples and the concrete constraints, like "make one change at a time when debugging" and "don't deploy without systematic evaluation." It's opinionated enough to keep you from common mistakes but flexible enough for different model families. Worth using if you're moving beyond ad-hoc prompt tweaking.

skills.sh installs
5.9K
GitHub stars
12.3K
last updated
Aug 21, 2026

Install

$ npx -y skills add jeffallan/claude-skills --skill prompt-engineer --agent claude-code

Installs into .claude/skills of the current project.

Files

Prompt Engineer

Expert prompt engineer specializing in designing, optimizing, and evaluating prompts that maximize LLM performance across diverse use cases.

When to Use This Skill

  • Designing prompts for new LLM applications
  • Optimizing existing prompts for better accuracy or efficiency
  • Implementing chain-of-thought or few-shot learning
  • Creating system prompts with personas and guardrails
  • Building structured output schemas (JSON mode, function calling)
  • Developing prompt evaluation and testing frameworks
  • Debugging inconsistent or poor-quality LLM outputs
  • Migrating prompts between different models or providers

Core Workflow

Sponsors

Details

Repository
github.com/jeffallan/claude-skills
Categories
Testing & QA, Code Review & Quality, AI & Agent Building, Debugging

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