Validate Skills for Claude

Validates skills in this repo against agentskills.io spec and Claude Code best practices. Use via /validate-skills command.

666 tokens

context cost

the whole folder, loaded on every use

files

instructions only

copies elsewhere

how many repositories repackaged it

1575

stars on the repo

on the repository, not the skill itself

Install

one command, takes just this skill from the repository

npx skills add https://github.com/callstackincubator/agent-skills --skill validate-skills

The instruction itself

6 sections, as written by the author

Validate Skills

Validate all skills in skills/ against the agentskills.io spec and Claude Code best practices.

Validation Checklist

For each skill directory, verify:

Spec Compliance (agentskills.io)

| Check | Rule |

|-------|------|

| name format | 1-64 chars, lowercase alphanumeric + hyphens, no leading/trailing/consecutive hyphens |

| name matches directory | Directory name must equal name field |

| description length | 1-1024 characters, non-empty |

| Optional fields valid | license, metadata, compatibility if present |

Best Practices (Claude Code)

| Check | Rule |

|-------|------|

| Description format | Third person, describes what + when to use |

| Body length | Under 500 lines |

| Loading is one-level deep | SKILL.md is the only progressive-disclosure entry point: every reference file must be reachable from SKILL.md. References may cross-link each other for navigation (see note below). |

| Links are markdown | Use text not bare filenames |

| No redundancy | Don't repeat description in body |

| Concise | Only add context Claude doesn't already have |

> One-level-deep vs. cross-linking. The one-level-deep rule targets *progressive-disclosure loading chains* — a reference that can only be discovered by loading another reference first (SKILL.md → a.md → b.md, where b.md is not linked from SKILL.md). That is a defect: it hides content from the loader.

> It does not forbid *navigational* cross-links. Per AGENTS.md, reference files end with a "Related Skills" footer linking sibling references, and this is required. A cross-link is fine as long as both endpoints are also reachable directly from SKILL.md. Only flag a reference that is reachable *exclusively* through another reference.

How to Run

Find all skill directories:

   fd -t d -d 1 . skills/

For each skill, read SKILL.md and check against the rules above

Report issues in this format:

   ## Validation Results

   ### skills/example-skill
   - [PASS] name format valid
   - [FAIL] name "example" doesn't match directory "example-skill"
   - [PASS] description length OK (156 chars)

References

Other skills for the same job

different authors, same section of the catalogue

Skill Creator

by anthropics

vendor ×10

Create new skills, modify and improve existing skills, and measure skill performance. Use when users want to create a skill from scratch, edit, or optimize an existing skill, run evals to test a skill, benchmark skill performance with variance analysis, or optimize a skill's description for better triggering accuracy.

Guide for creating effective skills. This skill should be used when users want to create a new skill (or update an existing skill) that extends Claude's capabilities with specialized knowledge, workflows, or tool integrations.

Replace with description of the skill and when Claude should use it.

35 tokens

Dispatching Parallel Agents

by ZhanlinCui

×5

Use when facing 2+ independent tasks that can be worked on without shared state or sequential dependencies

This skill should be used when the user wants to "create a skill", "add a skill to plugin", "write a new skill", "improve skill description", "organize skill content", or needs guidance on skill structure, progressive disclosure, or skill development best practices for Claude Code plugins.

Helps users discover and install agent skills when they ask questions like "how do I do X", "find a skill for X", "is there a skill that can...", or express interest in extending capabilities. This skill should be used when the user is looking for functionality that might exist as an installable skill.

Use when creating new skills, editing existing skills, or verifying skills work before deployment

26k tokens scripts

How to use it

Copy the folder

Take callstackincubator/validate-skills from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.