mcp-builder

Build an MCP server by designing tools, registering them with standardized naming, validating inputs with Pydantic or Zod, and handling errors robustly. This Skill automates scaffolding Python MCP servers with connection handling, best practices, and support for stdio, SSE, and HTTP transports to enable LLMs to interact with external services.

FastMCP is a Python framework for building MCP servers, while the MCP SDK supports Node/TypeScript implementations. Both enable tool registration and validation; choose FastMCP for Python workflows or the MCP SDK for JavaScript/TypeScript environments. This Skill covers best practices and patterns for both.

Validate inputs using Pydantic schemas in Python or Zod in TypeScript, defining required fields and types explicitly in tool metadata. Implement error handling for edge cases, set character limits, and use pagination for large responses. This Skill provides reference implementations and guidelines for production-ready validation.

Yes. This Skill includes evaluation scripts and guidelines to test MCP server performance, validate protocol adherence, and measure response times across stdio, SSE, and HTTP transports. Testing ensures optimal operation and identifies bottlenecks under constrained context.

Multi-transport support—stdio, SSE, and HTTP—enables flexibility for different deployment scenarios. This Skill demonstrates configurable transport setup and explains when each protocol suits your use case, helping you build scalable integrations without duplicating core logic.

Use consistent tool naming conventions, attach explicit metadata annotations, validate all inputs with schemas, handle errors gracefully, and configure response formats as JSON or Markdown. This Skill provides references and scaffolding for Python and Node.js implementations that enforce these patterns.