SKILL.md Format Specification

VerifiedSafe

Describes the SKILL.md format used by n-skills, following the agentskills.io standard. Specifies required and optional frontmatter, body structure, bundled resources, and best practices. Helps in creating or understanding standardized AI coding skills.

Sby Skills Guide Bot
DocumentationBeginner
6/2/2026
Claude CodeCodex
#skill-definition#markdown-format#agentskills#documentation-standards

Recommended for

Automated summary

This skill defines the structure for creating SKILL.md files that describe AI agent skills, including frontmatter, body sections, and bundled resources.

Strengths

  • Provides a standardized format for skill documentation.
  • Includes both required and optional frontmatter fields.
  • Allows bundling of additional resources like scripts and references.
  • Promotes best practices like front-loading triggers.

Limitations

  • Does not cover how to actually implement the skill logic.
  • Limited to text-based documentation, not executable code.
  • May not be compatible with all AI agent platforms without adaptation.
When to use it

When you need to create a reusable, well-documented skill definition for an AI agent following the agentskills.io standard.

When not to use it

When you are looking for a ready-made skill implementation rather than a documentation template.

Security analysis

Safe
Quality score90/100

This SKILL.md is purely a documentation specification with no executable code, network operations, or system modifications. It poses no security risk.

No concerns found

How this analysis is made

Examples

Create a code review skill definition
Create a SKILL.md file for a skill that reviews Python code for style and security issues. Include frontmatter with description, triggers like 'review this code', and a setup section requiring pylint and bandit.
Generate a SKILL.md template
Generate a SKILL.md template following the agentskills.io standard with required frontmatter (name, description), a setup section, and an examples section. Use 'example-skill' as the name.
Document a data analysis skill
Write a SKILL.md for a skill that analyzes CSV data and generates summary statistics. Include compatibility for claude-code and codex, and reference a scripts/analyze.py file.

SKILL.md Format Specification

This document describes the SKILL.md format used by n-skills, which follows the agentskills.io standard.

Required Frontmatter

---
name: skill-name           # lowercase, hyphens only
description: |             # Include trigger phrases
  What it does.
  When to use it.
  Requirements.
---

Optional Frontmatter

version: 1.0.0
license: Apache-2.0
author:
  name: Your Name
  github: username
keywords: [tag1, tag2]
compatibility:
  claude-code: true
  codex: true

Body Structure

# Skill Name

## Description (optional)
Expand on the frontmatter description if needed.

## Setup
Any prerequisites or configuration needed.

## Commands/Usage
How to use the skill.

## Examples
Concrete usage examples.

## Advanced
Link to references/ for detailed documentation.

Bundled Resources

Skills can include additional resources:

skill-name/
├── SKILL.md           # Required
├── references/        # Extended documentation
│   └── advanced.md
├── scripts/           # Executable code
│   └── helper.py
└── assets/            # Templates, files for output
    └── template.json

Best Practices

  1. Keep SKILL.md concise - Under 500 lines
  2. Front-load triggers - Put trigger phrases in the description
  3. Use references/ - Move detailed docs out of SKILL.md
  4. Provide examples - Concrete, copy-pasteable examples
  5. Document requirements - API keys, dependencies, etc.

From the file to a first result

The download contains exactly the content displayed on this page. This copy may differ from the latest version in the source repository.

View the source and supporting files

This download contains SKILL.md only. Any scripts, references, templates and dependencies are not included. Get the required files from the source, preserving their directory structure, before continuing.

1. Download the file

Download SKILL.md

From the root of a test project, save the file as .skill-downloads/skill-md-format-specification-mm5t8ch9/SKILL.md, or use the command below. This folder is for inspecting the skill before installation.

Command for macOS/Linux or WSL: requires a POSIX shell and curl. On Windows without WSL, use the download button and create the folder manually.

mkdir -p '.skill-downloads/skill-md-format-specification-mm5t8ch9' && curl --fail --show-error --location 'https://skills-guides.com/api/skills/skill-md-format-specification-mm5t8ch9/download' --output '.skill-downloads/skill-md-format-specification-mm5t8ch9/SKILL.md.part' && mv '.skill-downloads/skill-md-format-specification-mm5t8ch9/SKILL.md.part' '.skill-downloads/skill-md-format-specification-mm5t8ch9/SKILL.md'

2. Check prerequisites

Read SKILL.md before using it. If it references scripts or external services, inspect them and prepare the required access in your test environment.

No recognized prerequisites section in this file. This does not mean it is self-contained: libraries, tools and access requirements may be mentioned elsewhere in the content or source repository.

The platforms on this page are catalog indications. The paths below follow tool documentation; they do not prove this skill has been run in those tools. No minimum tool version is confirmed for this listing.

3. Load the skill

This file does not provide a usable name/description header for this native procedure. It remains available to download and inspect; use the manual method below.

Manual method or another tool: attach SKILL.md to a conversation, or open it in an agent that can read files. Include any required supporting resources. No universal folder is recognized by every tool.

4. Try a first task

Use a short, synthetic input: an API endpoint, a small document or an interface brief. In a new conversation, attach the file or give the agent its path, then adapt this request:

Read .skill-downloads/skill-md-format-specification-mm5t8ch9/SKILL.md and apply its instructions to this example: [describe a test input]. Identify any missing files, dependencies or access. Produce the result requested by the skill without inventing data or running unreviewed scripts.

Expected result: output matching the skill instructions, or a precise list of missing prerequisites. A read confirmation alone does not validate a first use. If an external resource is unavailable, that path remains untested.

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