Scopeblind Gateway vs Captcha MCP

In-depth architectural comparison of the Scopeblind Gateway and Captcha MCP 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 Scopeblind Gateway 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: INTERNAL_API_KEY.
• Primary tools included: Per-tool policy enforcement (block, rate limit, min tier), Shadow mode logs all tool calls without blocking, Enforce mode applies policies to tool calls.

Explore Scopeblind Gateway Details

Choose Captcha MCP 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: CAPTCHA_URL, HTTP_MODE, PORT.

Feature & Specification Comparison

Specification	Scopeblind Gateway tomjwxf Security	Captcha MCP zekebuilds-lab Security
Summary	Security gateway that wraps any MCP server with per-tool policies, approval gates, and optional Ed25519-signed receipts. Shadow mode logs every tool call; enforce mode blocks, rate-limits, or requires approval.	L402 Lightning paywall + Hashcash proof-of-work gate for MCP tool calls. Free tier solves a PoW challenge; paid tier pays a Lightning invoice via self-hosted LNBits. No accounts, no API keys, no third-party SaaS. Drop-in middleware for any MCP server. npx @powforge/captcha-mcp.
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": {
    "tomjwxf-scopeblind-gateway": {
      "command": "npx",
      "args": [
        "-y",
        "@scopeblind/passport"
      ],
      "env": {
        "INTERNAL_API_KEY": "YOUR_INTERNAL_API_KEY_HERE"
      }
    }
  }
}

{
  "mcpServers": {
    "zekebuilds-lab-captcha-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@powforge/captcha-mcp"
      ],
      "env": {
        "CAPTCHA_URL": "YOUR_CAPTCHA_URL_HERE",
        "HTTP_MODE": "YOUR_HTTP_MODE_HERE",
        "PORT": "YOUR_PORT_HERE"
      }
    }
  }
}

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