mskills

mskills is a CLI tool to manage "Agent Skills" for various AI agents (Claude, Codex, Gemini, Copilot, Antigravity) in a centralized way.

Installation

From npm (Recommended)

npm install -g mskills

From Source

git clone https://github.com/yurakawa/mskills.git
cd mskills
npm install
npm run build
npm link

Usage

1. Add a Skill

Register a skill directory to mskills. mskills validates the skill directory based on the Agent Skills specification.

Valid Skill Requirements:

• A SKILL.md file must exist in the root of the skill directory.
• SKILL.md must start with YAML frontmatter containing name and description.
• The name in SKILL.md must match the parent directory name.
• For more details, see the official specification.

mskills add <skill-name> <path/to/skill>

Example:

mskills add hello-world ./examples/hello-world

2. Enable Agents

Select which agents you want to apply the skills to.

mskills agents add <agent-names...>

Tip

See Supported Agents for the list of available agent names (e.g., claude, cursor, github-copilot-cli).

Example:

# Enable for Claude and GitHub Copilot
mskills agents add claude github-copilot-cli

3. Apply Skills

Sync your configured skills to the enabled agents' configuration directories.

mskills apply

This will create symbolic links (default) or copies of your skills in the agent's skills directory (e.g., ~/.claude/skills/hello-world).

4. Generate XML Prompt for AI Agents

Generate an XML block of available skills to be injected into an AI agent's system prompt.

mskills prompt

This will output an XML block like:

<available_skills>
  <skill>
    <name>hello-world</name>
    <description>A simple hello world skill</description>
    <location>/Users/yurakawa/.mskills/skills/hello-world/SKILL.md</location>
  </skill>
</available_skills>

Commands

Command	Description
mskills add <name> <path>	Register a skill.
mskills remove <names...>	Remove registered skills.
mskills list	List registered skills.
mskills agents add <names...>	Enable target agents.
mskills agents remove <names...>	Disable target agents.
mskills agents list	List enabled agents.
mskills apply	Apply skills to enabled agents.
mskills apply --force	Force overwrite existing skills.
mskills prompt	Generate XML prompt for AI agents.

Configuration

mskills stores its configuration and data in the following directory:

• Config File: ~/.mskills/config.json
• Internal Skills Cache: ~/.mskills/skills (used for internal management)

Supported Agents

Agent	CLI Name	Skills Directory
Claude	claude	~/.claude/skills
Cursor	cursor	~/.cursor/skills
Codex	codex	~/.codex/skills
Gemini	gemini	~/.gemini/skills
GitHub Copilot CLI	github-copilot-cli	~/.copilot/skills
Antigravity	antigravity	~/.gemini/antigravity/skills

Demo

A demo skill is included in examples/hello-world.

# 1. Add the demo skill
mskills add hello-world ./examples/hello-world

# 2. Enable an agent (e.g., Claude)
mskills agents add claude

# 3. Apply
mskills apply

# 4. Check result
ls -l ~/.claude/skills/hello-world