skill-creator

skill-creator is a skill for Claude Code, Codex from ChatLunaLab/chatluna. It costs 121 tokens per session (3,945 once invoked), scanned A, original, AGPL-3.0.

A guide for creating, editing, improving, or reviewing AgentSkills and their SKILL.md files.

In plain words
What is it for?
Use it to build a skill, audit an existing one, reorganize its files, or validate its contents.
Why use it?
It provides a workflow for keeping skills accurate, organized, and properly structured.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Use it to build a skill, audit an existing one, reorganize its files, or validate its contents.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/chatlunalab/chatluna/skill-creator
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add ChatLunaLab/chatluna --skill skill-creator
Clone the repo
git clone --depth 1 https://github.com/ChatLunaLab/chatluna

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for skill-creator

README.md
[![agentmods](https://agentmods.dev/badge/skills/chatlunalab/chatluna/skill-creator/github.svg)](https://agentmods.dev/skills/chatlunalab/chatluna/skill-creator)
Your own site
<a href="https://agentmods.dev/skills/chatlunalab/chatluna/skill-creator"><img src="https://agentmods.dev/badge/skills/chatlunalab/chatluna/skill-creator/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for skill-creator

Your own site · 80×15
<a href="https://agentmods.dev/skills/chatlunalab/chatluna/skill-creator"><img src="https://agentmods.dev/badge/skills/chatlunalab/chatluna/skill-creator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 121 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,945 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 2 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high Rogue Agent · line 208
    Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.
    Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
  • high Rogue Agent · line 315
    Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.
    Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
How audits are shown
Origin unknown No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00121 $0.03945
Opus 5.5 $0.00048 $0.01578
Sonnet 5.5 $0.00024 $0.00789
Haiku 4.5 $0.00012 $0.00394

Measured 1mo ago against content hash c24f65fc88b9, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

skill-creator scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.

The scan reads SKILL.md. This mod also ships 5 executable files (scripts/init_skill.py, scripts/package_skill.py, scripts/quick_validate.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

packages/extension-agent/resources/skills/skill-creator/SKILL.md · 373 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

Files

What ships with it

6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 1mo ago First seen · 373 lines · 121 tokens per session scan A c24f65fc88b9

Subscribe to this mod's changes

skill-creator is a skill published in the GitHub repository ChatLunaLab/chatluna (444 stars, last pushed 4d ago), licensed AGPL-3.0. It adds 121 tokens to every session and 3,945 once invoked, about $0.0005 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.