MCP Firewall vs Shellward

In-depth architectural comparison of the MCP Firewall and Shellward 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 MCP Firewall 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: YAML-based inbound and outbound policies, Secret scanning with regex and entropy checks, Response redaction and prompt-injection blocking.

Explore MCP Firewall Details

Choose Shellward 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).
• You have access to required keys: SHELLWARD_MODE, SHELLWARD_LOCALE, SHELLWARD_THRESHOLD, SHELLWARD_BASELINE_PATH.
• Primary tools included: Stdio MCP server with local execution, Prompt injection detection for Chinese and English text, PII, credential, and sensitive-data scanning.

Feature & Specification Comparison

Specification	MCP Firewall behrensd Security	Shellward jnMetaCode Security
Summary	Deterministic security proxy (iptables for MCP) that intercepts tool calls, enforces YAML policies, scans for secret leakage, and logs everything. No AI, no cloud.	AI Agent Security Middleware & MCP Server with 8-layer defense including prompt injection detection, DLP data flow tracking, command blocking, and PII detection. 7 MCP tools, zero dependencies.
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": {
    "behrensd-mcp-firewall": {
      "command": "npx",
      "args": [
        "-y",
        "mcpwall"
      ]
    }
  }
}

{
  "mcpServers": {
    "jnmetacode-shellward": {
      "command": "npx",
      "args": [
        "-y",
        "shellward"
      ],
      "env": {
        "SHELLWARD_MODE": "YOUR_SHELLWARD_MODE_HERE",
        "SHELLWARD_LOCALE": "YOUR_SHELLWARD_LOCALE_HERE",
        "SHELLWARD_THRESHOLD": "YOUR_SHELLWARD_THRESHOLD_HERE",
        "SHELLWARD_BASELINE_PATH": "YOUR_SHELLWARD_BASELINE_PATH_HERE"
      }
    }
  }
}

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