README_MCP_HUB.md

Universal MCP Hub (Sandboxed)

Universal MCP Server running in paranoid mode — built on PyFundaments and licensed under ESOL.

The goal was simple: too many MCP servers out there with no sandboxing, hardcoded keys, and zero security thought. This one is different. No key = no tool = no crash. The Guardian (main.py) controls everything. app/mcp.py gets only what it needs, nothing more.

• MCP_HUB Built with Claude (Anthropic) as a typing tool. Architecture, security decisions
• Pyfundaments by Volkan Sah read ESOL

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MCP Client Configuration (SSE)

To connect Claude Desktop or any MCP client to this hub:

{
  "mcpServers": {
    "pyfundaments-hub": {
      "url": "https://YOUR_USERNAME-universal-mcp-hub.hf.space/sse"
    }
  }
}

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Architecture

main.py  ← Guardian: initializes all services, controls what app/ receives
  └── app/mcp.py  ← Sandbox: registers only tools with valid keys
        ├── LLM tools    (Anthropic, Gemini, OpenRouter, HuggingFace)
        ├── Search tools (Brave, Tavily)
        ├── DB tools     (only if DATABASE_URL is set)
        └── System tools (always active)

The Guardian pattern: app/mcp.py never reads os.environ directly. It receives a fundaments dict from main.py — and only what main.py decides to give it.

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Security Notes

• All API keys loaded via Secrets (env vars) — never hardcoded
• list_active_tools returns key names only, never values
• DB tools are read-only by design (SELECT only, enforced at application level)
• Direct execution of app/mcp.py is blocked by design
• Built on PyFundaments — a security-first Python architecture for developers

PyFundaments is not perfect. But it's more secure than most of what runs in production.

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License

Apache License 2.0 + ESOL 1.1

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"I use AI as a tool, not as a replacement for thinking." — Volkan Kücükbudak