skills/mcp-builder

🔗 View on GitHub: anthropics/skills/mcp-builder

🚀 Quick Installation

Guide for creating high-quality MCP (Model Context Protocol) servers.

Claude Code Plugin

/plugin marketplace add anthropics/skills
/plugin install example-skills@anthropic-agent-skills

What It Does

Create MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use this skill when:

• 🔌 Building MCP servers to integrate external APIs or services
• 🛠️ Working with Python (FastMCP) or Node/TypeScript (MCP SDK)
• 📐 Designing tool schemas and APIs for LLM consumption

Four Key Principles

1. API Coverage vs. Workflow Tools

Balance comprehensive API endpoint coverage with specialized workflow tools. When uncertain, prioritize comprehensive API coverage.

2. Tool Naming and Discoverability

Use clear, descriptive tool names with consistent prefixes (e.g., github_create_issue, github_list_repos) and action-oriented naming.

3. Context Management

Design tools that return focused, relevant data with concise descriptions and pagination support.

4. Actionable Error Messages

Error messages should guide agents toward solutions with specific suggestions and next steps.

Recommended Stack

Development Workflow

1. Understand the API — Review service documentation, endpoints, auth
2. Tool Selection — Prioritize comprehensive API coverage
3. Project Setup — Use language-specific guides for structure
4. Implementation — Create tools with proper schemas, error handling, pagination
5. Testing — Use MCP Inspector: npx @modelcontextprotocol/inspector
6. Evaluation — Create comprehensive evals to test effectiveness

Tool Annotations

• readOnlyHint — true/false
• destructiveHint — true/false
• idempotentHint — true/false
• openWorldHint — true/false

Resources

• 📋 MCP Specification
• ⚡ TypeScript SDK
• 🐍 Python SDK

📚 What are skills? | 🎓 Agent Skills Spec