skill-creator

Create, evaluate, and iteratively improve Claude skills with benchmark-driven testing.

Updated Aug 17, 2026
One-click install
npx skills add https://github.com/kai-kou/gem-hunter --skill skill-creator-kai-kou
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: skill-creator
Source: https://github.com/kai-kou/gem-hunter/tree/main/.claude/skills/skill-creator
Command: npx skills add https://github.com/kai-kou/gem-hunter --skill skill-creator-kai-kou

SYSTEM DOCUMENTATION & REQUIREMENTS

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

What problem does it solve? Writing effective skills for Claude is hard to get right on the first try — descriptions may undertrigger, instructions may be ambiguous, and there is no built-in way to measure whether a skill actually improves outputs. This Skill provides a structured draft-test-review-iterate workflow with quantitative benchmarking so skill quality is measured rather than guessed. ## Core Features & Use Cases - Guided Skill Authoring: Captures intent through interview questions, then drafts SKILL.md with proper frontmatter, progressive disclosure structure, and writing patterns. - Parallel Evaluation Runs: Spawns with-skill and baseline subagent runs for each test prompt, captures timing and token data, and grades outputs against assertions. - Benchmark Aggregation & Review Viewer: Aggregates grading results into benchmark.json/benchmark.md with pass rates and deltas, and generates an HTML review interface for qualitative human feedback. - Description Optimization: Runs an automated loop that tests trigger accuracy against should-trigger/should-not-trigger queries and iteratively improves the skill description. - Use Case: You want to build a skill that generates weekly status reports. This Skill helps you draft it, create realistic test prompts, run side-by-side comparisons against a no-skill baseline, review outputs in a browser viewer, and refine until the benchmark shows consistent improvement. ## Quick Start Ask the AI to create a new skill for your workflow, for example: help me create a skill that converts meeting notes into structured action items. ## Environment Notes The full workflow (subagents, browser viewer, description optimization) is designed for Claude Code. On Claude.ai or Cowork, adaptations apply — no subagents on Claude.ai, and static HTML output instead of a server in Cowork.

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 draft the SKILL.md with name and description frontmatter, create 2-3 realistic test prompts, and run with-skill versus baseline evaluations to iterate on quality.

How do I test whether my skill actually improves outputs?▼

Run each test prompt twice in parallel — once with the skill and once without — then grade both against objective assertions. The aggregate_benchmark.py script produces pass rates, timing, and token deltas so you can compare configurations quantitatively.

How can I improve skill triggering accuracy?▼

Use the description optimization procedure: generate 20 realistic should-trigger and should-not-trigger queries, review them with the user, then run the automated loop that evaluates and rewrites the description across up to 5 iterations, selecting by held-out test score.

Does skill-creator work on Claude.ai or only Claude Code?▼

The full workflow with parallel subagents and browser-based review is designed for Claude Code. On Claude.ai there are no subagents so tests run sequentially without baselines; in Cowork, use the --static flag to generate a standalone HTML review file.

What is the difference between model-invoked and user-invoked skills?▼

Model-invoked skills (the default) can be triggered by Claude, humans, or other skills, with the description always in context. User-invoked skills set disable-model-invocation: true, which hides the description and blocks Skill-tool invocation entirely, so only humans can start them.

When should a skill include scripts, references, or assets?▼

Add scripts for deterministic repetitive tasks that test runs keep reimplementing, references for documentation loaded on demand when SKILL.md approaches 500 lines, and assets for templates or files used in outputs. This progressive disclosure keeps the main skill file lean.