Writes, refactors, and evaluates prompts for LLMs — generating optimized prompt templates, structured output schemas, evaluation rubrics, and test suites.
NewMaintained
Automatic
◆AI Engineer pack
Last verified 10/9/2026
What it changes
Passed 19 of 22 test cases with the skill, and 19 of 22 without it.
Without skill86%
With skill86%
0 fixed19 passed either way3 still failing0 broke
Pass-rate lift
0 pp
Tokens
+31%
Agent turns
0%
Response time
-35%
Model gemini-3.6-flashMeasured 10/9/2026v219 of 22 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
What's inside
The instructions your model reads when the skill loads.
SKILL.md123 lines7 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
Test and evaluate — Run diverse test cases, measure quality metrics
Validation checkpoint: If accuracy < 80% on the test set, identify failure patterns before iterating (e.g., ambiguous instructions, missing examples, edge case gaps)
Iterate and optimize — Make one change at a time; refine based on failures, reduce tokens, improve reliability
Document and deploy — Version prompts, document behavior, monitor production
Provides workflows to write, debug, and optimize prompts for LLMs, including few-shot example selection, chain-of-thought structuring, system prompt design, and template composition. Use when the user asks to write or improve a prompt, wants help with few-shot examples, chain-of-thought, system prompts, prompt templates, or asks how to get better results from an LLM.