Shield vs Beelzebub

In-depth architectural comparison of the Shield and Beelzebub MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.

Which MCP Server Should You Choose?

Choose Shield when:

• You need dedicated capabilities in the Security domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• Primary tools included: Pre-execution MCP call guardrails, TOFU tool-catalog pinning, Tool description and result scanning.

Explore Shield Details

Choose Beelzebub when:

• You need dedicated capabilities in the Security domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• Primary tools included: MCP, SSH, HTTP, TCP, and TELNET decoys, YAML service definitions with regex matching, OpenAI and Ollama response generation.

Explore Beelzebub Details

Feature & Specification Comparison

Specification	Shield AperionAI Security	Beelzebub mariocandela Security
Summary	Local guardrail proxy for AI coding agents. Wraps any MCP server (stdio or Streamable HTTP) and blocks destructive tool calls — DROP TABLE, rm -rf, force-push — before they execute. MCP supply-chain protection: TOFU tool-catalog pinning against rug pulls, plus tool-description and tool-result scanning for tool poisoning and prompt injection. 51 starter rules, approval gates, audit logging. Single binary, Apache-2.0.	Beelzebub is a honeypot framework that lets you build honeypot tools using MCP. Its purpose is to detect prompt injection or malicious agent behavior. The underlying idea is to provide the agent with tools it would never use in its normal work.
Category & Scope

Tools & Capabilities Breakdown

Ready-to-Paste Client Configurations

Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).

{
  "mcpServers": {
    "aperionai-shield": {
      "command": "npx",
      "args": [
        "-y",
        "@modelcontextprotocol/server-postgres"
      ]
    }
  }
}

{
  "mcpServers": {
    "mariocandela-beelzebub": {
      "command": "npx",
      "args": [
        "-y",
        "mariocandela-beelzebub"
      ]
    }
  }
}

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