MCP Builder
Build high-quality MCP (Model Context Protocol) servers enabling LLMs to interact with external services through well-designed tools.
Four-Phase Development Process
Phase 1: Deep Research and Planning
- API Design Balance — Choose between comprehensive endpoint coverage or specialized workflow tools based on client needs
- Tool Naming — Use consistent prefixes (e.g.,
github_create_issue,github_list_repos) and action-oriented names - Framework Choice — TypeScript recommended for SDK quality and broad AI model support
- Documentation Review — Start with MCP protocol sitemap, then study language-specific SDKs
Phase 2: Implementation
Set up project structure following language-specific guidelines:
- Build shared utilities (API client, error handling, pagination)
- Implement tools with:
- Input schemas using Zod (TypeScript) or Pydantic (Python)
- Output schemas for structured data
- Clear descriptions and error messages
- Proper annotations (
readOnlyHint,destructiveHint, etc.)
Phase 3: Review and Test
- Verify code quality (no duplication, consistent error handling, full types)
- Build and test using MCP Inspector
- Run language-specific validation
Phase 4: Create Evaluations
- Design 10 complex, realistic evaluation questions
- Ensure questions are independent, read-only, and verifiable
- Format results as XML with question-answer pairs
Tool Naming Conventions
# Good
github_create_issue
github_list_repos
stripe_charge_card
# Avoid
create_issue (no prefix — ambiguous)
issueCreate (wrong casing)
Key Resources
- MCP Best Practices — Universal guidelines for naming, responses, and security
- Language Guides — Python (FastMCP) and TypeScript implementations
- Evaluation Guide — Comprehensive testing methodology
- MCP Inspector — Browser-based tool for interactive testing
Installation
npx skills add https://github.com/anthropics/skills --skill mcp-builder
Mirrored from https://github.com/anthropics/skills — original author: anthropics, license: Apache-2.0. This is an unclaimed mirror. Content and ownership transfer to the author when they claim this account.