Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or services, whether in Python (FastMCP) or Node/TypeScript (MCP SDK).
92
73%
Does it follow best practices?
Impact
94%
2.23xAverage score across 10 eval scenarios
Advisory
Suggest reviewing before use
Optimize this skill with Tessl
npx tessl skill review --optimize ./skills/anthropic-mcp-builder/SKILL.mdSecurity
1 medium severity finding. This skill can be installed but you should review these findings before use.
The skill exposes the agent to untrusted, user-generated content from public third-party sources, creating a risk of indirect prompt injection. This includes browsing arbitrary URLs, reading social media posts or forum comments, and analyzing content from unknown websites.
Third-party content exposure detected (high risk: 0.80). The SKILL.md workflow explicitly instructs the agent to fetch and read public web pages (e.g., "https://modelcontextprotocol.io/sitemap.xml", raw GitHub URLs like https://raw.githubusercontent.com/modelcontextprotocol/... and the note "Use web search and WebFetch as needed"), so the agent will ingest untrusted, publicly‑hosted content that can materially influence implementation decisions and tool behavior.
353f6a8
If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.