skill-creator

Create, evaluate, and iteratively improve Claude skills with benchmarked test runs.

Updated Mar 26, 2026
One-click install
npx skills add https://github.com/LGJ-Jonathan/Jonathan_Global_Claude_Skills --skill skill-creator-lgj-jonathan
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: skill-creator
Source: https://github.com/LGJ-Jonathan/Jonathan_Global_Claude_Skills/tree/main/skill-creator
Command: npx skills add https://github.com/LGJ-Jonathan/Jonathan_Global_Claude_Skills --skill skill-creator-lgj-jonathan

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) and assets (resource) components.

What problem does it solve? Writing a skill that triggers reliably and produces good outputs is hard to do by intuition alone. This Skill guides the full lifecycle of skill development: drafting SKILL.md files, running test prompts with and without the skill, grading results against assertions, and optimizing the description field for accurate triggering. ## Core Features & Use Cases - Guided Skill Authoring: Interviews the user about intent, trigger contexts, and output formats, then drafts a SKILL.md following progressive disclosure and writing-style best practices. - Evaluation & Benchmarking: Runs test prompts in parallel with-skill and baseline configurations, grades outputs against assertions, and aggregates pass rates, timing, and token usage into benchmark reports with an interactive HTML review viewer. - Description Optimization: Generates realistic should-trigger and should-not-trigger queries, then runs an automated train/test optimization loop to improve the skill's triggering accuracy. - Use Case: You want a skill that formats weekly sales spreadsheets. This Skill helps you draft it, creates three realistic test prompts, runs them with and without the skill, shows you a side-by-side comparison in a browser viewer, and iterates based on your feedback until the outputs are consistently correct. ## Quick Start Help me create a new skill that converts meeting transcripts into structured action-item lists, then test it with a few example prompts.

Frequently Asked Questions about skill-creator

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I create a new Claude skill from scratch?

Start by defining what the skill should do, when it should trigger, and its expected output format. Then write a SKILL.md with name and description frontmatter, draft 2-3 realistic test prompts, and iterate based on evaluation results.

How do I test whether my skill actually improves outputs?

Run each test prompt twice in parallel: once with the skill and once without as a baseline. Grade both against the same assertions, then compare pass rates, timing, and token usage in the aggregated benchmark report.

How do I improve a skill description so it triggers correctly?

Generate about 20 realistic queries split between should-trigger and should-not-trigger cases, including tricky near-misses. The optimization loop tests description variants against these queries and selects the best by held-out test score.

What makes a good SKILL.md description field?

The description should state both what the skill does and specific contexts when to use it, since it is the primary triggering mechanism. Slightly pushy phrasing listing concrete trigger phrases helps counteract undertriggering.

When should a skill include scripts versus inline instructions?

Bundle a script when test runs show subagents repeatedly writing the same helper code across cases, or when a task is deterministic and repetitive. Scripts save every future invocation from reinventing the same logic.

Does skill evaluation work on Claude.ai without subagents?

Yes, but with adaptations: run test prompts sequentially yourself instead of spawning subagents, skip baseline runs and quantitative benchmarking, and collect feedback inline in the conversation rather than through the browser viewer.