Shrike MCP Server

Shrike MCP

Runtime security for AI agents. 12 MCP tools. 10-layer detection pipeline. Works without an API key.

Shrike MCP is the Model Context Protocol server for the Shrike Security platform. It gives AI agents real-time security tools to scan prompts, responses, SQL queries, file writes, CLI commands, web searches, and agent-to-agent messages — catching prompt injection, jailbreaks, data leakage, and multi-turn manipulation before they cause harm.

Shrike Security Platform

Shrike Security is a runtime security platform for AI agents. It guards inputs, outputs, tool calls, and agent-to-agent communication through a 10-layer detection pipeline — from sub-millisecond pattern matching to LLM-powered semantic analysis and multi-turn session correlation.

This repo is the MCP server — one of several ways to integrate:

Quick Start

Works immediately — no API key required. Anonymous usage gets L1-L5 pattern-based detection. Register for free to unlock LLM-powered semantic analysis.

1. Add to your MCP client config:

{
  "mcpServers": {
    "shrike-security": {
      "command": "npx",
      "args": ["-y", "shrike-mcp"]
    }
  }
}

2. (Optional) Add an API key for full pipeline access:

{
  "mcpServers": {
    "shrike-security": {
      "command": "npx",
      "args": ["-y", "shrike-mcp"],
      "env": {
        "SHRIKE_API_KEY": "your-api-key"
      }
    }
  }
}

Get a free key at shrikesecurity.com/signup — instant, no credit card.

3. Your agent now has 12 security tools. Every prompt, response, and tool call can be scanned before execution.

Twelve Tools

How It Works

Shrike uses a scan-sandwich pattern — every agent action is scanned on both sides:

User Input → scan_prompt → LLM Processing → scan_response → User Output
                              ↓
              Tool Call (SQL, File, Command, Search)
                              ↓
            scan_sql_query / scan_file_write / scan_command / scan_web_search
                              ↓
                       Tool Execution

Agent-to-Agent Communication:
  Inbound A2A → scan_a2a_message → Process → scan_a2a_message → Outbound A2A
  Discovery   → scan_agent_card  → Trust decision

Inbound scans catch injection attacks. Outbound scans catch data leaks. Tool-specific scans catch SQL injection, path traversal, command injection, and PII exposure. A2A scans catch east-west injection between agents. Flagged actions trigger human-in-the-loop approval via check_approval.

Enterprise tier adds session correlation (L9) — tracking multi-turn patterns like trust escalation, payload splitting, and blocked retry sequences across an entire conversation.

Detection Pipeline

Every scan runs through a multi-layer cascade. Lower layers are sub-millisecond pattern matching; higher layers add LLM-powered semantic analysis. Tier determines how deep the scan goes.

The cascade optimizer exits early when high-confidence detection is achieved at a lower layer — so most scans complete in under 10ms without needing the LLM layer.

Tiers

All 12 tools are available on every tier. Tiers control detection depth and volume.

Anonymous (no API key): Pattern-based detection only (L1-L5). Good for evaluation and basic protection.

Community (free): Adds LLM-powered semantic analysis (L6-L7). Catches zero-day attacks that evade regex. Register at shrikesecurity.com/signup.

Pro/Enterprise: Full pipeline including response intelligence (L8) and multi-turn session correlation (L9).

Compliance

Built-in policy catalogues across 7 frameworks:

Configuration

Environment Variables

Claude Desktop

{
  "mcpServers": {
    "shrike-security": {
      "command": "npx",
      "args": ["-y", "shrike-mcp"],
      "env": { "SHRIKE_API_KEY": "your-api-key" }
    }
  }
}

Cursor

Add to .cursor/mcp.json:

{
  "mcpServers": {
    "shrike-security": {
      "command": "npx",
      "args": ["-y", "shrike-mcp"],
      "env": { "SHRIKE_API_KEY": "your-api-key" }
    }
  }
}

Windsurf

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "shrike-security": {
      "command": "npx",
      "args": ["-y", "shrike-mcp"],
      "env": { "SHRIKE_API_KEY": "your-api-key" }
    }
  }
}

Security Model

This server implements a fail-closed security model:

• Network timeouts result in BLOCK (not allow)
• Backend errors result in BLOCK (not allow)
• Unknown content types result in BLOCK (not allow)

This prevents bypass attacks via service disruption.

Response Format

Blocked:

{
  "blocked": true,
  "threat_type": "prompt_injection",
  "severity": "high",
  "confidence": "high",
  "guidance": "This prompt contains patterns consistent with instruction override attempts.",
  "request_id": "req_lxyz123_a8f3k2m9"
}

Safe:

{
  "blocked": false,
  "request_id": "req_lxyz123_a8f3k2m9"
}

Links

• Shrike Security — Sign up, dashboard, docs
• GitHub — Source code, issues
• npm — Package registry
• TypeScript SDK — npm install shrike-guard
• Python SDK — pip install shrike-guard
• Smithery — MCP marketplace listing

License

Apache License 2.0 — See LICENSE for details.