mcp-builder

Design MCP servers for LLMs to call external services via defined tools.

1|Updated Jun 30, 2024
One-click install
npx skills add https://github.com/DigiBanks99/menlo --skill mcp-builder-digibanks99
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: mcp-builder
Source: https://github.com/DigiBanks99/menlo/tree/main/.claude/skills/mcp-builder
Command: npx skills add https://github.com/DigiBanks99/menlo --skill mcp-builder-digibanks99

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill guides developers in building high-quality MCP servers that let LLMs safely and effectively interact with external services through well-defined tools. It covers Python (FastMCP) and TypeScript (MCP SDK) implementations, tool design, input/output schemas, error handling, and testing practices.

Core Features & Use Cases

  • Tool-first design: create small, composable tools with strict input/output schemas.
  • Language-agnostic: supports Python and Node/TypeScript MCP SDKs.
  • Validation & Testing: includes runtime validation with Pydantic/Zod, pagination, and error handling patterns.
  • Use Case: Build an MCP server to wrap a third-party API and expose it to an LLM via well-documented tools.

Quick Start

Scaffolding a minimal MCP server with one tool, wiring a transport (stdio or streamable HTTP), and verifying tool invocation.

Frequently Asked Questions about mcp-builder

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

FAQPage Schema
How do I design an MCP server for LLM integrations?

To design an MCP server for LLM integrations, you create small, composable tools with strict input/output schemas using Python (FastMCP) or TypeScript (MCP SDK). The server enforces structured responses and comprehensive error handling to let LLMs safely call external services.

Can I build MCP servers using both Python and TypeScript?

Yes, you can build MCP servers using both Python and TypeScript. The implementation scope explicitly covers Python with FastMCP and TypeScript with the MCP SDK, supporting scaffolding for both local and remote deployments.

What is the best way to validate inputs in an MCP server?

The best way to validate MCP server inputs is to enforce strict schemas using Pydantic for Python or Zod for TypeScript. This tool-first design approach ensures runtime validation, handles pagination, and manages comprehensive error handling patterns.

How do I expose a third-party API to an LLM via MCP?

To expose a third-party API to an LLM via MCP, you wrap the API by building a server with clearly defined, well-documented tools. You wire a transport like stdio or streamable HTTP and verify the tool invocation to enable structured LLM interactions.

Does MCP server design support remote deployments?

Yes, MCP server design supports remote deployments. The scope covers wiring transports such as stdio or streamable HTTP, enabling both local and remote deployments for your LLM integration tools.

Why do my MCP tools need strict input and output schemas?

MCP tools need strict input and output schemas to ensure LLMs interact safely and effectively with external services. Enforcing structured responses and runtime validation with Pydantic or Zod prevents unexpected behavior and handles errors comprehensively.