About
Prompt Lab is a systematic prompt engineering skill that enables developers to iterate on LLM prompts using structured evaluation against ground truth data and model comparison. Its key feature is a self-correction loop that automatically sends invalid outputs back to the LLM for fixing. Use this skill when you need to rigorously test and improve prompts for taxonomy classification or QRA (Question-Reasoning-Answer) generation tasks.
Quick Install
Claude Code
Recommendednpx skills add grahama1970/agent-skills -a claude-code/plugin add https://github.com/grahama1970/agent-skillsgit clone https://github.com/grahama1970/agent-skills.git ~/.claude/skills/prompt-labCopy and paste this command in Claude Code to install this skill
GitHub Repository
Frequently asked questions
What is the prompt-lab skill?
prompt-lab is a Claude Skill by grahama1970. Skills package instructions and resources that Claude loads on demand, so Claude can perform prompt-lab-related tasks without extra prompting.
How do I install prompt-lab?
Use the install commands on this page: add prompt-lab to Claude Code as a plugin, or clone its repository into your skills directory, then restart Claude so it picks up the skill.
What category does prompt-lab belong to?
prompt-lab is in the Meta category, tagged ai and testing.
Is prompt-lab free to use?
Yes. prompt-lab is listed on AIMCP and free to install. It runs inside Claude, so no separate service account is required to use the skill itself.
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