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).
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Low-risk findings.
1 low severity finding. Worth noting, but not necessarily harmful.
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 evaluation harness (scripts/evaluation.py) can load tool definitions from a remote MCP server URL (e.g., https://example.com/mcp) at runtime and passes those tools to the LLM (controlling agent prompts and enabling remote tool execution), so an attacker-controlled MCP endpoint could directly influence prompts and execute code via tool calls.
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- openstatusHQ/data-table-filters
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- Security analysis
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