MCP Guard

MCP Guard by General Analysis is an MCP wrapper server that detects and blocks prompt injection attacks against MCP clients (Cursor, Claude Code, Claude Desktop, etc.).

What is MCP Guard?

MCP Guard acts as a proxy server between your MCP clients and servers, analyzing each tool output for potential prompt injection attacks before they reach your AI assistant. This provides critical protection against:

• Tool Output Manipulation: Prevents malicious servers from injecting commands
• Context Hijacking: Blocks attempts to override system prompts
• Data Exfiltration: Stops unauthorized data access attempts
• Command Injection: Prevents execution of unintended operations

How It Works

1. Intercept: MCP Guard intercepts all tool outputs from MCP servers
2. Analyze: Each output is sent to GA’s guardrail server for analysis
3. Block/Allow: Malicious content is blocked, safe content passes through
4. Alert: Security incidents are logged and reported

Community & Support

• GitHub Repository 
• Discord Community 
• MCP Guard Blog