Local MCP Servers

Local MCP servers run on your machine as child processes, communicating via stdio. This is an alternative to Bolt for users who prefer to run tools directly on their system.

Tip

Prefer Bolt for security tools. Local MCP requires manual tool installation. See Bolt for the recommended approach with 100+ pre-installed Kali tools.

🎞️ MARP SLIDE: local-architecture.md

Local MCP stdio transport architecture

📸 SCREENSHOT: local-mcp-config.png

Local MCP server configuration in cyberstrike.json

When to Use Local MCP

Local MCP servers are best for:

Offline environments - No network access required
Low latency - Direct process communication
Custom tools - Your own MCP servers
Privacy - Data never leaves your machine

Architecture

flowchart LR
    subgraph Cyberstrike["Cyberstrike Process"]
        Agent[AI Agent]
        Client[MCP Client]
    end

    subgraph LocalMCP["Local MCP Server"]
        Stdio[Stdio Transport]
        Handler[Request Handler]
        Tools[Tool Functions]
    end

    Agent --> Client
    Client <-->|stdin/stdout| Stdio
    Stdio --> Handler
    Handler --> Tools

    style Cyberstrike fill:#3b82f6,color:#fff
    style LocalMCP fill:#10b981,color:#fff

Overview

Local MCP servers offer:

Zero network latency
Full data privacy
Offline operation
Custom tool integration
Direct system access

Adding via TUI

The easiest way to add a local MCP server is directly from the Cyberstrike TUI using the /mcps command.

Opening the MCP Manager

Type /mcps in the TUI to open the MCP management dialog. It lists all configured servers with their current status:

✓ Enabled — connected and active
○ Disabled — configured but inactive

Keyboard shortcuts: space to toggle enable/disable, a to add a new server, Enter to act on the selected server.

Steps to Add a Local Server

Press a (or select “Add MCP Server”) → choose Local
Command — enter the command to start the server, e.g. npx my-mcp-server
Environment variables (optional) — enter as KEY=VALUE, KEY2=VALUE2
Server name — auto-derived from the command (lowercase, alphanumeric/hyphen/underscore); edit if needed
Cyberstrike tests the connection before saving — if the connection fails, the server is not added and an error is shown; if it succeeds, the server is written to config

Config Written by TUI

{
  "mcp": {
    "my-local-server": {
      "type": "local",
      "command": ["npx", "my-mcp-server"],
      "environment": { "KEY": "VALUE" }
    }
  }
}

Configuration

Basic Setup

{
  "mcp": {
    "servers": {
      "my-tools": {
        "command": "node",
        "args": ["./mcp-server/index.js"]
      }
    }
  }
}

Project-Level Configuration

{
  "mcp": {
    "servers": {
      "project-tools": {
        "command": "python",
        "args": ["-m", "project_mcp"]
      }
    }
  }
}

Server Types

Node.js Servers

{
  "mcp": {
    "servers": {
      "node-tools": {
        "command": "npx",
        "args": ["-y", "@modelcontextprotocol/server-filesystem"]
      }
    }
  }
}

Python Servers

{
  "mcp": {
    "servers": {
      "python-tools": {
        "command": "python",
        "args": ["-m", "mcp_server"]
      }
    }
  }
}

Binary Executables

{
  "mcp": {
    "servers": {
      "binary-tools": {
        "command": "/usr/local/bin/mcp-scanner"
      }
    }
  }
}

Docker Containers

{
  "mcp": {
    "servers": {
      "docker-tools": {
        "command": "docker",
        "args": ["run", "-i", "--rm", "mcp-tools:latest"]
      }
    }
  }
}

Environment Variables

Pass to Server

{
  "mcp": {
    "servers": {
      "api-tools": {
        "command": "node",
        "args": ["server.js"],
        "env": {
          "API_KEY": "{env:MY_API_KEY}",
          "DEBUG": "true"
        }
      }
    }
  }
}

Inherit Environment

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "python",
        "args": ["server.py"],
        "inheritEnv": true
      }
    }
  }
}

Working Directory

Set Working Directory

{
  "mcp": {
    "servers": {
      "project-tools": {
        "command": "node",
        "args": ["server.js"],
        "cwd": "/path/to/project"
      }
    }
  }
}

Relative Paths

{
  "mcp": {
    "servers": {
      "local-tools": {
        "command": "./scripts/mcp-server.sh"
      }
    }
  }
}

Popular Local Servers

Filesystem Server

Access files and directories:

{
  "mcp": {
    "servers": {
      "filesystem": {
        "command": "npx",
        "args": ["-y", "@modelcontextprotocol/server-filesystem", "/path/to/allow"]
      }
    }
  }
}

SQLite Server

Query local databases:

{
  "mcp": {
    "servers": {
      "sqlite": {
        "command": "npx",
        "args": ["-y", "@modelcontextprotocol/server-sqlite", "--db", "data.db"]
      }
    }
  }
}

Git Server

Git operations:

{
  "mcp": {
    "servers": {
      "git": {
        "command": "npx",
        "args": ["-y", "@modelcontextprotocol/server-git"]
      }
    }
  }
}

Server Lifecycle

Startup

Servers start when:

Cyberstrike launches (if configured)
First tool from server is used (lazy start)

Auto-Start

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "node",
        "args": ["server.js"],
        "autoStart": true
      }
    }
  }
}

Lazy Start

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "node",
        "args": ["server.js"],
        "autoStart": false
      }
    }
  }
}

Restart on Failure

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "node",
        "args": ["server.js"],
        "restart": {
          "enabled": true,
          "maxRetries": 3,
          "delay": 1000
        }
      }
    }
  }
}

Health Checks

Timeout Configuration

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "node",
        "args": ["server.js"],
        "timeout": 30000
      }
    }
  }
}

Connection Verification

> Check MCP server status

Output:

MCP Server Status:
- my-tools: connected (5 tools)
- filesystem: connected (3 tools)
- sqlite: disconnected (starting...)

Resource Limits

Memory Limits

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "node",
        "args": ["--max-old-space-size=512", "server.js"]
      }
    }
  }
}

CPU Priority

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "nice",
        "args": ["-n", "10", "node", "server.js"]
      }
    }
  }
}

Security Considerations

Sandboxing

{
  "mcp": {
    "servers": {
      "untrusted": {
        "command": "docker",
        "args": ["run", "--rm", "-i", "--network=none", "mcp-server"]
      }
    }
  }
}

Permission Restrictions

{
  "mcp": {
    "servers": {
      "readonly": {
        "command": "node",
        "args": ["server.js"],
        "permissions": {
          "filesystem": "read",
          "network": false
        }
      }
    }
  }
}

Debugging

Enable Logging

{
  "mcp": {
    "servers": {
      "tools": {
        "command": "node",
        "args": ["server.js"],
        "env": {
          "DEBUG": "mcp:*"
        }
      }
    }
  }
}

View Logs

# Server logs location
tail -f ~/.cyberstrike/logs/mcp-my-tools.log

Manual Testing

# Test server directly
echo '{"jsonrpc":"2.0","method":"tools/list","id":1}' | node server.js

Troubleshooting

Server Not Starting

Error: Failed to start MCP server: my-tools

Check:

Command exists and is executable
Working directory is correct
Dependencies are installed

Connection Timeout

Error: MCP server connection timeout

Solutions:

Increase timeout value
Check server startup time
Verify server is responding

Tool Not Found

Error: Tool not found: my-tools/scanner

Verify:

Server is running
Tool is exported by server
Tool name is correct

Tip

Use lazy start for servers with slow startup times to avoid slowing down Cyberstrike launch.

Bolt / MCP Overview - Architecture and concepts
Bolt - Docker-based Kali tools (recommended)
Remote Servers - Remote MCP configuration
Creating Servers - Build custom servers