MCP Knowledge Base Server

A lightweight Model Context Protocol (MCP) server for MySQL database querying and schema exploration. This tool enables AI agents to understand database structure and fetch data through a safe, read-only interface.

Features

• Schema Discovery: Get complete database schema including tables, columns, data types, and comments
• Key Relationships: Understand table relationships through primary keys, foreign keys, and unique keys
• Safe Query Execution: Execute SELECT queries with automatic validation and pagination
• Table Exploration: Search and describe tables easily

Available Tools

Tool	Description
get_schema	Get complete database schema for all tables
get_keys	Get all keys and relationships for JOIN operations
raw_query	Execute SELECT queries with pagination (read-only)
describe_table	Get detailed information about a specific table
get_tables	List all tables with metadata
search_tables	Search tables and columns by pattern

Quick Start

1. Install Dependencies

npm install

2. Configure Environment

Copy .env.example to .env and update with your database credentials:

DB_HOST=127.0.0.1
DB_PORT=3306
DB_USER=admin
DB_PASSWORD=secret
DB_NAME=ez_ccsd1wy
DB_CONNECTION_LIMIT=10
QUERY_TIMEOUT_MS=30000
MAX_ROWS_PER_PAGE=100

3. Run the Server

# Development mode (with auto-reload)
npm run dev

# Production mode
npm start

4. Use with Claude/Cline

Add the server to your MCP configuration:

{
  "mcpServers": {
    "knowledgebase": {
      "command": "node",
      "args": ["/path/to/knowledgebase/src/index.js"],
      "env": {
        "DB_HOST": "127.0.0.1",
        "DB_PORT": "3306",
        "DB_USER": "admin",
        "DB_PASSWORD": "secret",
        "DB_NAME": "ez_ccsd1wy"
      }
    }
  }
}

Usage Examples

Get Database Schema

// Get all tables and their columns
await tools.get_schema()

Get Table Relationships

// Understand how tables connect
await tools.get_keys()

Execute a Query

// Simple SELECT query with pagination
await tools.raw_query({
  query: "SELECT * FROM users WHERE active = 1",
  page: 1,
  limit: 50
})

Describe a Table

// Get detailed table structure
await tools.describe_table({
  tableName: "users"
})

Search for Tables

// Find tables or columns
await tools.search_tables({
  pattern: "user",
  type: "all" // or "tables", "columns"
})

Security

• Read-Only Access: Only SELECT queries are allowed
• Query Validation: All queries are validated before execution
• Timeout Protection: Queries have a configurable timeout (default 30s)
• Pagination: Automatic pagination prevents overwhelming responses

Project Structure

knowledgebase/
├── src/
│   ├── index.js          # Main MCP server
│   ├── database.js       # Database connection pool
│   └── tools/
│       ├── schema.js     # Schema tools
│       └── query.js      # Query tools
├── .env                  # Environment configuration
├── .env.example          # Environment template
├── .nvmrc                # Node.js version
├── package.json          # Dependencies
└── README.md             # This file

Node.js Version

This project uses Node.js 20.0.0. Use nvm to manage versions:

nvm use

Documentation

• Agent Instructions - Guide for AI agents extending this tool
• API Reference - Detailed tool specifications

License

ISC