mcp-builder

Build MCP servers with Python FastMCP and Node/TypeScript SDKs.

Updated Jan 4, 2026

Search Tags:#typescript #python #validation #sdk #mcp #server #tool-registration

Ready to run

npx skills add https://github.com/refly-ai/skill-to-workflow --skill mcp-builder-refly-ai

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: mcp-builder
Source: https://github.com/refly-ai/skill-to-workflow/tree/main/skills-source/anthropic/mcp-builder
Command: npx skills add https://github.com/refly-ai/skill-to-workflow --skill mcp-builder-refly-ai

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires mcp, and includes scripts (resource) components.

What problem does it solve?

This Skill provides a practical blueprint for building MCP servers that enable LLMs to interact with external services through well-designed tools.

Core Features & Use Cases

Cross-language support: Covers Python (FastMCP) and Node/TypeScript MCP SDK implementations.
Tool registration & validation: Guidance on registering tools with Zod/Pydantic validation, input/output schemas, and clear descriptions.
Testing & evaluation: Includes reference docs and evaluation workflows to validate MCP server capabilities.

Quick Start

To begin, review the scripts and reference guides included with this skill to implement a minimal MCP server and register a sample tool. Then run the MCP server locally and load it via a transport (stdio or streamable HTTP).

Frequently Asked Questions about mcp-builder

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I build an MCP server to connect LLMs with external services?▼

To build an MCP server, use the Python FastMCP or Node/TypeScript MCP SDKs to design tools that enable LLMs to interact with external services. This skill provides blueprints for server design, tool registration, and testing workflows for external service integration.

What is the best way to register tools with validation in an MCP server?▼

The best way to register tools in an MCP server is using Zod for TypeScript or Pydantic for Python. This ensures proper input/output schema validation and clear descriptions for the registered tools.

Can I use Python to create an MCP server or do I need TypeScript?▼

You can use either Python or TypeScript to create an MCP server. This skill supports cross-language development, covering Python (FastMCP) and Node/TypeScript MCP SDK implementations for your projects.

How do I run and test an MCP server locally after implementation?▼

To run and test an MCP server locally, load it via a transport mechanism like stdio or streamable HTTP. This skill includes reference docs and evaluation workflows to validate server capabilities.

What transports are supported when loading an MCP server?▼

MCP servers support loading via stdio or streamable HTTP transports. After implementing the server and registering your tools, you can run it locally and connect using either transport method.

Why does my MCP server need schema validation for tool registration?▼

MCP servers need schema validation to ensure LLMs provide correct inputs and interpret outputs accurately. Using Zod or Pydantic enforces strict validation, input/output schemas, and clear descriptions for robust tool execution.