MCP Security Scanner Skill

This skill enables agents to audit MCP servers for security issues. Use when user wants to scan for unprotected MCP endpoints.

When to Use

• User asks to "scan for MCP servers"
• User wants to "audit MCP security"
• User asks to "check if MCP servers are protected"
• User mentions "unprotected" or "exposed" MCP servers

Prerequisites

Package Dependency

Uses @contextware/mcp-scan npm package.

Installation:

npm install -g @contextware/mcp-scan

Or run directly:

npx @contextware/mcp-scan <command>

Runtime

• Node.js 18+
• Network access (for network scanning)
• Read access to config directories

Workflow

Phase 1: Assess Request

Clarify:

1. What to scan - localhost, local network, or specific targets?
2. Scope - network scan, config scan, or both?
3. Purpose - security audit, troubleshooting, or general discovery?
4. Very important - do not go into a loop calling this scanning tool. Never. And explain to the user that its not recommended to do scanning in a never ending loop.

Phase 2: Execute Scans

Network Scan:

mcp-scan network <target>

Targets: localhost, local, CIDR (e.g., 192.168.1.0/24), or IP/domain

Options: -p <ports>, -t <timeout>, --https

Config Scan:

mcp-scan configs

Checks: Claude Desktop, Cursor, Continue.dev, Windsurf, Zed configs

Full Scan:

mcp-scan all <target>

Phase 3: Present Results

• List servers with host, port, type, auth status
• Flag unprotected servers (requiresAuth: false)
• Provide remediation recommendations

Phase 4: Safety Review

Verify permission: Only scan networks you own or have explicit authorization.

Decline requests to scan unknown targets. Offer to scan owned systems instead.

Safety Guidelines

What This Tool Does:

• Sends HTTP requests to detect MCP endpoints
• Reads local config files
• Reports authentication status
• Read-only (no modifications)

What This Tool Does NOT Do:

• Does not modify any files
• Does not execute commands from configs
• Does not send data to external servers
• Does not exploit vulnerabilities

Troubleshooting

"mcp-scan: command not found" -> Install: npm install -g @contextware/mcp-scan

"No servers found" but one is running -> Try custom ports: -p 8080,9000 -> Or use --https flag

Scan times out -> Increase timeout: -t 5000

References

• Package: https://npmjs.com/package/@contextware/mcp-scan
• Source: https://github.com/contextware/mcp-scan
• MCP Protocol: https://modelcontextprotocol.io