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mcp-builder

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

2.23x
Quality

73%

Does it follow best practices?

Impact

94%

2.23x

Average score across 10 eval scenarios

SecuritybySnyk

Advisory

Suggest reviewing before use

Optimize this skill with Tessl

npx tessl skill review --optimize ./skills/anthropic-mcp-builder/SKILL.md
SKILL.md
Quality
Evals
Security

Security

1 medium severity finding. This skill can be installed but you should review these findings before use.

Medium

W011: Third-party content exposure detected (indirect prompt injection risk)

What this means

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.

Why it was flagged

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.

Report incorrect finding
Repository
boisenoise/skills-collections
Audited
Security analysis
Snyk

Is this your skill?

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.