Overview
Model Context Protocol (MCP) integration allows Cubent Coder to connect with external tools, services, and data sources. This powerful extensibility system enables the AI to access databases, APIs, cloud services, and custom tools while maintaining security and control.
What is MCP?
MCP (Model Context Protocol) is an open standard that enables AI models to securely connect to external resources:
- Standardized interface: Consistent way to connect tools and services
- Security-first: Built-in authentication and permission controls
- Extensible: Support for custom tools and integrations
- Interoperable: Works across different AI models and platforms
Built-in MCP Integrations
Database Connections
Connect to various databases:
# PostgreSQL
mcp_servers:
postgres:
command: "npx"
args: ["@modelcontextprotocol/server-postgres"]
env:
POSTGRES_CONNECTION_STRING: "postgresql://user:pass@localhost/db"
# SQLite
mcp_servers:
sqlite:
command: "npx"
args: ["@modelcontextprotocol/server-sqlite", "--db-path", "./data.db"]
File System Access
Enhanced file operations:
# File system server
mcp_servers:
filesystem:
command: "npx"
args: ["@modelcontextprotocol/server-filesystem", "/allowed/path"]
Web Services
Connect to external APIs:
# HTTP/REST API server
mcp_servers:
web_api:
command: "npx"
args: ["@modelcontextprotocol/server-fetch"]
env:
ALLOWED_HOSTS: "api.example.com,api.github.com"
Integrate with development services:
# GitHub integration
mcp_servers:
github:
command: "npx"
args: ["@modelcontextprotocol/server-github"]
env:
GITHUB_PERSONAL_ACCESS_TOKEN: "your_token_here"
Setting Up MCP Servers
Installation
Install MCP servers using npm:
# Install common MCP servers
npm install -g @modelcontextprotocol/server-postgres
npm install -g @modelcontextprotocol/server-sqlite
npm install -g @modelcontextprotocol/server-filesystem
npm install -g @modelcontextprotocol/server-fetch
Configuration
Configure MCP servers in your Cubent Coder settings:
{
"mcpServers": {
"database": {
"command": "npx",
"args": ["@modelcontextprotocol/server-postgres"],
"env": {
"POSTGRES_CONNECTION_STRING": "postgresql://localhost/mydb"
}
},
"files": {
"command": "npx",
"args": ["@modelcontextprotocol/server-filesystem", "/workspace"]
}
}
}
Authentication
Set up secure authentication:
{
"mcpServers": {
"github": {
"command": "npx",
"args": ["@modelcontextprotocol/server-github"],
"env": {
"GITHUB_PERSONAL_ACCESS_TOKEN": "${GITHUB_TOKEN}"
}
}
}
}
Database Queries
Query databases through MCP:
Query the users table to find all active users from the last 30 days
Create a new table for storing product reviews with appropriate indexes
Analyze the database schema and suggest optimizations
File Operations
Enhanced file system access:
Search for all TypeScript files that import React
Create a backup of the src/ directory
Find and replace all occurrences of the old API endpoint
API Interactions
Connect to external services:
Fetch the latest issues from our GitHub repository
Get weather data for New York from the weather API
Send a notification to our Slack channel about the deployment
Custom MCP Servers
Creating a Custom Server
Build your own MCP server:
import { Server } from '@modelcontextprotocol/sdk/server/index.js';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';
const server = new Server(
{
name: 'my-custom-server',
version: '1.0.0',
},
{
capabilities: {
tools: {},
resources: {},
},
}
);
// Add custom tools
server.setRequestHandler('tools/list', async () => {
return {
tools: [
{
name: 'custom_tool',
description: 'My custom tool',
inputSchema: {
type: 'object',
properties: {
input: { type: 'string' }
}
}
}
]
};
});
// Handle tool calls
server.setRequestHandler('tools/call', async (request) => {
const { name, arguments: args } = request.params;
if (name === 'custom_tool') {
// Implement your custom logic here
return {
content: [
{
type: 'text',
text: `Processed: ${args.input}`
}
]
};
}
throw new Error(`Unknown tool: ${name}`);
});
// Start the server
const transport = new StdioServerTransport();
await server.connect(transport);
Server Configuration
Configure your custom server:
{
"mcpServers": {
"custom": {
"command": "node",
"args": ["./my-custom-server.js"]
}
}
}
Advanced MCP Features
Resource Management
Access and manage resources:
// List available resources
server.setRequestHandler('resources/list', async () => {
return {
resources: [
{
uri: 'file:///workspace/config.json',
name: 'Configuration',
description: 'Application configuration'
}
]
};
});
// Read resource content
server.setRequestHandler('resources/read', async (request) => {
const { uri } = request.params;
// Return resource content
});
Prompt Templates
Create reusable prompt templates:
server.setRequestHandler('prompts/list', async () => {
return {
prompts: [
{
name: 'code_review',
description: 'Code review template',
arguments: [
{
name: 'file_path',
description: 'Path to the file to review'
}
]
}
]
};
});
Streaming Responses
Handle large data with streaming:
server.setRequestHandler('tools/call', async (request) => {
// Return streaming response for large datasets
return {
content: [
{
type: 'text',
text: 'Processing large dataset...'
}
],
isError: false
};
});
Security and Best Practices
Access Control
Implement proper access controls:
{
"mcpServers": {
"database": {
"command": "npx",
"args": ["@modelcontextprotocol/server-postgres"],
"env": {
"POSTGRES_CONNECTION_STRING": "postgresql://readonly_user:pass@localhost/db"
},
"permissions": {
"allowedOperations": ["SELECT"],
"deniedTables": ["sensitive_data", "user_passwords"]
}
}
}
}
Environment Variables
Use environment variables for secrets:
# .env file
GITHUB_TOKEN=your_github_token
DATABASE_URL=postgresql://localhost/mydb
API_KEY=your_api_key
Validation and Sanitization
Validate all inputs:
server.setRequestHandler('tools/call', async (request) => {
const { arguments: args } = request.params;
// Validate inputs
if (!args.query || typeof args.query !== 'string') {
throw new Error('Invalid query parameter');
}
// Sanitize inputs
const sanitizedQuery = sanitizeSQL(args.query);
// Execute safely
return executeQuery(sanitizedQuery);
});
Troubleshooting
Common Issues
Server connection failed:
- Check server installation
- Verify configuration syntax
- Review environment variables
Permission denied:
- Check file system permissions
- Verify authentication credentials
- Review access control settings
Tool not found:
- Ensure server is running
- Check tool registration
- Verify server capabilities
Debugging
Enable debug logging:
{
"mcpServers": {
"debug": true,
"logLevel": "debug"
}
}
Monitor server logs:
# View MCP server logs
tail -f ~/.cubent/mcp-servers.log
Next Steps
