arkhe-claude-plugins: Skill for Claude Code

.claude/skills/skill-validator/SKILL.md

skill-validator is a skill for Claude Code from joaquimscosta/arkhe-claude-plugins. It costs 79 tokens per session (708 once invoked), scanned A, original, MIT.

A checker for validating coding-agent skills against a defined set of writing, structure, file, security, hook, and MCP rules.

In plain words
What is it for?
Use it when creating, changing, reviewing, or preparing a skill for publication.
Why use it?
It finds problems before a skill is published, such as missing metadata, broken links, unsafe code, or incorrect file organization.

Skill for Claude Code

Written for Claude Code: argument-hint in frontmatter.

This is joaquimscosta/arkhe-claude-plugins's own configuration. It tells Claude Code how to work on arkhe-claude-plugins itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything arkhe-claude-plugins configures →

Reuse

Borrowing it

Nothing to install: this file belongs to joaquimscosta/arkhe-claude-plugins. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/joaquimscosta/arkhe-claude-plugins/main/.claude/skills/skill-validator/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/joaquimscosta/arkhe-claude-plugins

Made for: Claude Code.

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-validator

README.md
[![agentmods](https://agentmods.dev/badge/skills/joaquimscosta/arkhe-claude-plugins/skill-validator/github.svg)](https://agentmods.dev/skills/joaquimscosta/arkhe-claude-plugins/skill-validator)
Your own site
<a href="https://agentmods.dev/skills/joaquimscosta/arkhe-claude-plugins/skill-validator"><img src="https://agentmods.dev/badge/skills/joaquimscosta/arkhe-claude-plugins/skill-validator/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-validator

Your own site · 80×15
<a href="https://agentmods.dev/skills/joaquimscosta/arkhe-claude-plugins/skill-validator"><img src="https://agentmods.dev/badge/skills/joaquimscosta/arkhe-claude-plugins/skill-validator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 79 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 708 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 pass 7 Sept 2026
How audits are shown
Origin original 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 $0.00079 $0.00708
Opus 5 $0.00039 $0.00354
Sonnet 5 $0.00016 $0.00142
Haiku 4.5 $0.00008 $0.00071

Measured 9d ago against content hash 86a805c8e15a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

skill-validator 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 9d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/validate_skill.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.

.claude/skills/skill-validator/SKILL.md · 88 lines

How it starts

The opening of the file, as written. The whole thing — 88 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Skill Validator

Run automated checks against 62 rules covering frontmatter, structure, content, files, references, security, hooks, and MCP.

Quick Start

scripts/validate_skill.py /path/to/skill-directory

With severity filter:

scripts/validate_skill.py /path/to/skill --min-severity warning

Validation Categories

Category Rules Checks
Frontmatter FM001-FM018 Required fields, naming, description, context/agent, maxTurns, memory, disable-model-invocation
Structure SS001-SS006 Line limits, progressive disclosure
Content CW001-CW009 Writing style, terminology, string substitution, dynamic context injection, ultrathink
Files FO001-FO007 Naming conventions, forbidden files
References RI001-RI003 Broken links, orphan files
Security SC001-SC005 eval/exec, undocumented constants
Hooks HK001-HK003 Hook structure, handler format, matcher format
MCP MC001 MCP server configuration format

Severity Levels

Level Action
CRITICAL Must fix before publishing
ERROR Should fix
WARNING Consider fixing
SUGGESTION Optional improvement

Output Example

=== Skill Validation Report: my-skill ===

Summary: 0 critical, 1 error, 2 warnings, 1 suggestion

[ERROR] SS002: SKILL.md exceeds 500 lines (523 lines)
  Location: SKILL.md
  Fix: Split content into WORKFLOW.md, EXAMPLES.md, TROUBLESHOOTING.md

[WARNING] CW001: Second-person language detected
  Location: SKILL.md:45
  Found: "You should create..."
  Fix: Use imperative: "Create..."

Command Options

--min-severity {critical,error,warning,suggestion}  # Filter output
--format {text,json}                                # Output format
--ignore RULE1,RULE2                                # Skip specific rules

Common Issues

"False positive on second-person"

  • Context-appropriate "you" may be acceptable
  • Use --ignore CW001 to suppress

Read the full file on GitHub · 88 lines

Files

What ships with it

4 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. 9d ago First seen · 88 lines · 79 tokens per session scan A 86a805c8e15a

Subscribe to this mod's changes

skill-validator is a skill published in the GitHub repository joaquimscosta/arkhe-claude-plugins (21 stars, last pushed 25d ago), licensed MIT. It adds 79 tokens to every session and 708 once invoked, about $0.0004 per session on Opus 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.