build-mcp
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).
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Low
Low-risk findings worth noting
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Low-risk findings.
2 low severity findings. Worth noting, but not necessarily harmful.
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
The skill explicitly instructs the agent to use WebFetch and web search to load public URLs (e.g., https://modelcontextprotocol.io/llms-full.txt and raw.githubusercontent.com links) as required steps in Phase 1, meaning the agent will ingest untrusted, user-accessible third-party content that can materially influence tool design and subsequent actions.
W012: Unverifiable external dependency detected (runtime URL that controls agent).
What this means
The skill fetches instructions or code from an external URL at runtime, and the fetched content directly controls the agent’s prompts or executes code. This dynamic dependency allows the external source to modify the agent’s behavior without any changes to the skill itself.
Why it was flagged
The skill explicitly instructs using WebFetch at runtime to load https://modelcontextprotocol.io/llms-full.txt (and the SDK READMEs at https://raw.githubusercontent.com/modelcontextprotocol/python-sdk/main/README.md and https://raw.githubusercontent.com/modelcontextprotocol/typescript-sdk/main/README.md), which the agent must fetch and then use as authoritative protocol/specification guidance that directly controls its prompts/behavior and is treated as a required dependency.
- Repository
- NeoLabHQ/context-engineering-kit
- Commit
3711edf
- Audited
- Security analysis
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