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Documentation Index

Fetch the complete documentation index at: https://docs.mains.dev/llms.txt

Use this file to discover all available pages before exploring further.

Skills are packaged instructions that extend what your agents can do. Both the Claude Code and GitHub Copilot runtimes in Mains support skills — each with its own format, but the same idea: teach the agent domain-specific behavior it can invoke automatically.

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Claude Code Skills

Claude Code skills are SKILL.md files with YAML frontmatter and Markdown instructions. Claude discovers them at startup and autonomously invokes the right skill based on context.

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Skill Locations

LocationScope
.{your_project}/skills/Project skills — shared with your team via git
~/.claude/skills/User skills — personal, available across all projects

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Creating a Skill

Create a directory with a SKILL.md file inside: 
.{your_project}/skills/code-review/
└── SKILL.md
A SKILL.md file has YAML frontmatter followed by Markdown instructions: 
---
description: Reviews code changes for security vulnerabilities and best practices
allowed-tools: ["Read", "Grep", "Glob"]
---
# Code Review
When reviewing code, check for:
- SQL injection and XSS vulnerabilities
- Hardcoded credentials or secrets
- Missing input validation
- Error handling gaps
Provide findings as a numbered list with severity ratings.
The description field is what Claude uses to decide when to invoke the skill. Make it specific.

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Invoking Skills

Claude invokes skills automatically when a user request matches the skill’s description. You can also trigger them explicitly with slash commands: 
/code-review

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Copilot Skills

Copilot skills are directories containing a skill.json manifest, prompt files, and optional tool definitions.

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Structure

skills/
└── code-review/
    ├── skill.json
    └── prompts/
        └── system.md

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skill.json

{
  "name": "code-review",
  "displayName": "Code Review Assistant",
  "description": "Specialized code review capabilities",
  "version": "1.0.0",
  "prompts": ["prompts/system.md"]
}

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Loading Skills

Skills are loaded from configured directories when a Copilot session starts. You can disable specific skills by name if needed.

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Tips

  • Write clear descriptions — the agent uses them to decide when to invoke a skill
  • Limit tool access — only grant the tools a skill actually needs
  • Keep skills focused — one skill per domain works better than a catch-all
  • Version project skills — commit .claude/skills/ so your whole team benefits