mcp-builder
Comprehensive guide for building high-quality MCP servers that connect LLMs to external services.
- Four-phase workflow covering research, implementation, testing, and evaluation with language-specific guidance for TypeScript (recommended) and Python
- Emphasizes API coverage over workflow tools, clear tool naming with consistent prefixes, and actionable error messages for agent guidance
- Includes best practices for input/output schemas, pagination, response formatting, and tool annotations (readOnly, destructive, idempotent, openWorld hints)
- Provides reference documentation links for MCP protocol specification, SDK documentation, and language-specific implementation patterns with code examples
- Evaluation framework requiring 10 independent, read-only, complex questions with verifiable answers in XML format to validate LLM effectiveness with your server
MCP Server Development Guide
Overview
Create MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. The quality of an MCP server is measured by how well it enables LLMs to accomplish real-world tasks.
Process
🚀 High-Level Workflow
Creating a high-quality MCP server involves four main phases:
Phase 1: Deep Research and Planning
1.1 Understand Modern MCP Design
API Coverage vs. Workflow Tools:
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