Kastell vs R2mcp

In-depth architectural comparison of the Kastell and R2mcp 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 Kastell 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: Server security audits with remediation, SSH hardening and fail2ban setup, UFW firewall management.

Explore Kastell Details

Choose R2mcp when:

• You need dedicated capabilities in the Security domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: API Key required (Free / Open Source).
• You have access to required keys: R2MCP_AUTH_TOKEN.
• Primary tools included: Native C implementation using radare2 APIs, Supports CLI, r2 plugin, and HTTP MCP server modes, Connects to local or remote radare2/iaito sessions via r2pipe.

Feature & Specification Comparison

Specification	Kastell kastelldev Security	R2mcp radareorg Security
Summary	Server security auditing and hardening toolkit. 413 security checks across 29 categories (SSH, Firewall, Docker, TLS, HTTP Headers), CIS/PCI-DSS/HIPAA compliance mapping, 19-step production hardening, fleet management, and forensic evidence collection. Supports Hetzner, DigitalOcean, Vultr, and Linode. 13 MCP tools.	MCP server for Radare2 disassembler. Provides AI with capability to disassemble and look into binaries for reverse engineering.
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": {
    "kastelldev-kastell": {
      "command": "npx",
      "args": [
        "-y",
        "kastell"
      ]
    }
  }
}

{
  "mcpServers": {
    "radareorg-r2mcp": {
      "command": "npx",
      "args": [
        "-y",
        "radareorg-r2mcp"
      ],
      "env": {
        "R2MCP_AUTH_TOKEN": "YOUR_R2MCP_AUTH_TOKEN_HERE"
      }
    }
  }
}

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