n8n + Claude Code MCP integratie

n8n + Claude Code MCP Integratie: De Ultieme Gids

Wat is Model Context Protocol (MCP)?

Kernconcepten van MCP

• Bestanden op je computer
• Database records
• API responses
• Real-time data feeds

• Code executie
• API calls maken
• Bestanden aanmaken/wijzigen
• Workflows triggeren

Waarom MCP + n8n?

Prerequisites

1. Claude Code (Claude's coding assistant CLI)

• Installatie: npm install -g @anthropic-ai/claude-code
• Anthropic API key

1. n8n Instance

• Cloud account OF self-hosted installatie
• Webhook functionaliteit (standaard inbegrepen)

1. Node.js (versie 18+)

• Voor het draaien van de MCP server

1. Basis kennis van:

• n8n workflow creatie
• Claude Code gebruik
• JSON en REST APIs

Stap 1: n8n Webhook Configureren

1.1 Nieuwe Workflow Aanmaken

1. Open n8n
2. Klik op "Add workflow"
3. Noem het "Claude MCP Integration"

1.2 Webhook Node Toevoegen

Node: Webhook
HTTP Method: POST
Path: /claude-mcp
Authentication: Header Auth
  - Name: X-API-Key
  - Value: [genereer een secure key]
Response: Immediately respond
Response Code: 200

1.3 Request Router Toevoegen

Node: Switch
Routing Key: {{$json.body.action}}

Rules:
1. action === 'query_database' → Database pad
2. action === 'send_email' → Email pad  
3. action === 'create_task' → Task pad
4. action === 'get_status' → Status pad
Default: Error response

1.4 Voorbeeld Database Query Pad

Node: PostgreSQL (of Supabase)
Operation: Execute Query
Query: {{$json.body.query}}

→ Respond to Webhook
Response Body: 
{
  "success": true,
  "data": {{$json.data}},
  "count": {{$json.data.length}}
}

1.5 Voorbeeld Email Pad

Node: Email Send (SendGrid/Mailgun)
To: {{$json.body.to}}
Subject: {{$json.body.subject}}
Body: {{$json.body.message}}

→ Respond to Webhook
Response Body:
{
  "success": true,
  "message_id": "{{$json.id}}"
}

1.6 Activeer de Workflow

1. Klik op "Active" toggle
2. Kopieer de Production webhook URL
3. Test met cURL:

curl -X POST https://your-n8n.com/webhook/claude-mcp \
  -H "Content-Type: application/json" \
  -H "X-API-Key: your-api-key" \
  -d '{"action": "get_status", "data": {}}'

Stap 2: MCP Server voor n8n Maken

2.1 Project Setup

mkdir n8n-mcp-server
cd n8n-mcp-server
npm init -y
npm install @modelcontextprotocol/sdk node-fetch

2.2 MCP Server Code

import { Server } from '@modelcontextprotocol/sdk/server/index.js';
import { StdioServerTransport } from '@modelcontextprotocol/sdk/server/stdio.js';

const N8N_WEBHOOK_URL = process.env.N8N_WEBHOOK_URL;
const N8N_API_KEY = process.env.N8N_API_KEY;

// Helper functie voor n8n calls
async function callN8n(action, data = {}) {
  const response = await fetch(N8N_WEBHOOK_URL, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'X-API-Key': N8N_API_KEY
    },
    body: JSON.stringify({ action, ...data })
  });
  
  if (!response.ok) {
    throw new Error(`n8n error: ${response.status}`);
  }
  
  return response.json();
}

// MCP Server initialiseren
const server = new Server({
  name: 'n8n-integration',
  version: '1.0.0'
}, {
  capabilities: {
    tools: {}
  }
});

// Tool: Database Query
server.setRequestHandler('tools/list', async () => ({
  tools: [
    {
      name: 'query_database',
      description: 'Voer een SQL query uit op de database via n8n',
      inputSchema: {
        type: 'object',
        properties: {
          query: {
            type: 'string',
            description: 'De SQL query om uit te voeren'
          },
          params: {
            type: 'array',
            description: 'Query parameters voor prepared statements'
          }
        },
        required: ['query']
      }
    },
    {
      name: 'send_email',
      description: 'Verstuur een email via n8n',
      inputSchema: {
        type: 'object',
        properties: {
          to: { type: 'string', description: 'Ontvanger email adres' },
          subject: { type: 'string', description: 'Email onderwerp' },
          message: { type: 'string', description: 'Email inhoud' }
        },
        required: ['to', 'subject', 'message']
      }
    },
    {
      name: 'create_task',
      description: 'Maak een nieuwe taak aan in het project management systeem',
      inputSchema: {
        type: 'object',
        properties: {
          title: { type: 'string' },
          description: { type: 'string' },
          assignee: { type: 'string' },
          due_date: { type: 'string', format: 'date' },
          priority: { type: 'string', enum: ['low', 'medium', 'high'] }
        },
        required: ['title']
      }
    },
    {
      name: 'get_workflow_status',
      description: 'Check de status van n8n workflows',
      inputSchema: {
        type: 'object',
        properties: {
          workflow_name: { type: 'string' }
        }
      }
    },
    {
      name: 'trigger_workflow',
      description: 'Trigger een specifieke n8n workflow',
      inputSchema: {
        type: 'object',
        properties: {
          workflow_id: { type: 'string' },
          input_data: { type: 'object' }
        },
        required: ['workflow_id']
      }
    }
  ]
}));

// Tool execution handler
server.setRequestHandler('tools/call', async (request) => {
  const { name, arguments: args } = request.params;
  
  try {
    let result;
    
    switch (name) {
      case 'query_database':
        result = await callN8n('query_database', {
          query: args.query,
          params: args.params || []
        });
        break;
        
      case 'send_email':
        result = await callN8n('send_email', {
          to: args.to,
          subject: args.subject,
          message: args.message
        });
        break;
        
      case 'create_task':
        result = await callN8n('create_task', {
          title: args.title,
          description: args.description || '',
          assignee: args.assignee,
          due_date: args.due_date,
          priority: args.priority || 'medium'
        });
        break;
        
      case 'get_workflow_status':
        result = await callN8n('get_status', {
          workflow_name: args.workflow_name
        });
        break;
        
      case 'trigger_workflow':
        result = await callN8n('trigger_workflow', {
          workflow_id: args.workflow_id,
          input_data: args.input_data || {}
        });
        break;
        
      default:
        throw new Error(`Unknown tool: ${name}`);
    }
    
    return {
      content: [{
        type: 'text',
        text: JSON.stringify(result, null, 2)
      }]
    };
    
  } catch (error) {
    return {
      content: [{
        type: 'text',
        text: `Error: ${error.message}`
      }],
      isError: true
    };
  }
});

// Server starten
async function main() {
  const transport = new StdioServerTransport();
  await server.connect(transport);
  console.error('n8n MCP Server running...');
}

main().catch(console.error);

2.3 Package.json Configureren

{
  "name": "n8n-mcp-server",
  "version": "1.0.0",
  "type": "module",
  "main": "server.js",
  "bin": {
    "n8n-mcp": "./server.js"
  },
  "dependencies": {
    "@modelcontextprotocol/sdk": "^0.5.0",
    "node-fetch": "^3.3.0"
  }
}

Stap 3: Claude Code Configureren

3.1 Claude Code Settings

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Linux: ~/.config/claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json

3.2 MCP Server Toevoegen

{
  "mcpServers": {
    "n8n": {
      "command": "node",
      "args": ["/path/to/n8n-mcp-server/server.js"],
      "env": {
        "N8N_WEBHOOK_URL": "https://your-n8n.com/webhook/claude-mcp",
        "N8N_API_KEY": "your-secure-api-key"
      }
    }
  }
}

3.3 Herstart Claude Code

Stap 4: Praktijkvoorbeelden

Voorbeeld 1: Data Ophalen en Analyseren

Claude, haal alle orders op van deze week en geef me een samenvatting.

1. Claude roept query_database tool aan
2. n8n voert de query uit op je database
3. Data wordt teruggestuurd naar Claude
4. Claude analyseert en vat samen

Voorbeeld 2: Geautomatiseerde Rapportage

Claude, maak een rapport van de verkoopcijfers en email het naar het sales team.

1. query_database → Haal verkoopcijfers op
2. Claude analyseert en formatteert rapport
3. send_email → Verstuur naar sales@company.com

Voorbeeld 3: Task Management

Claude, maak een taak aan voor het development team om de bug in de checkout flow te fixen.

{
  "tool": "create_task",
  "arguments": {
    "title": "Fix checkout flow bug",
    "description": "Er is een bug gemeld in de checkout flow die...",
    "assignee": "development-team",
    "priority": "high",
    "due_date": "2024-01-20"
  }
}

Voorbeeld 4: Workflow Orchestratie

Claude, trigger de lead nurturing workflow voor alle nieuwe signups van vandaag.

1. query_database → Haal nieuwe signups op
2. Voor elke signup: trigger_workflow → Start nurturing sequence
3. Claude bevestigt aantal gestarte workflows

Advanced: Bi-directionele Communicatie

n8n naar Claude via API

Node: HTTP Request
Method: POST
URL: https://api.anthropic.com/v1/messages
Headers:
  - x-api-key: {{$env.ANTHROPIC_API_KEY}}
  - anthropic-version: 2023-06-01
  - Content-Type: application/json
Body:
{
  "model": "claude-3-sonnet-20240229",
  "max_tokens": 1024,
  "messages": [{
    "role": "user",
    "content": "Analyseer deze data: {{$json.data}}"
  }]
}

Event-driven Claude Triggers

Trigger: Database Trigger (nieuwe klacht)
   ↓
Code Node: Bereid context voor
   ↓
HTTP Request: Anthropic API
   - "Analyseer deze klacht en stel een response voor"
   ↓
IF: Is urgent?
   ├── Ja → Slack alert + Auto-response
   └── Nee → Queue voor review

Security Best Practices

1. API Key Management

# Gebruik environment variables, nooit hardcode
export N8N_API_KEY=$(openssl rand -hex 32)

2. Rate Limiting

// In een Code node aan het begin
const MAX_REQUESTS_PER_MINUTE = 30;
const clientId = $json.headers['x-client-id'] || 'default';

// Check rate limit in Redis/database
const requests = await getRequestCount(clientId, '1m');
if (requests >= MAX_REQUESTS_PER_MINUTE) {
  return [{
    json: { error: 'Rate limit exceeded' }
  }];
}

3. Input Validatie

// SQL injection preventie
const allowedTables = ['orders', 'products', 'customers'];
const table = $json.body.table;

if (!allowedTables.includes(table)) {
  throw new Error('Invalid table name');
}

// Prepared statements gebruiken
const query = 'SELECT * FROM ?? WHERE id = ?';
const params = [table, $json.body.id];

4. Audit Logging

// Log elke MCP actie
const auditLog = {
  timestamp: new Date().toISOString(),
  action: $json.body.action,
  user: $json.headers['x-user-id'],
  input: $json.body,
  result: $json.result,
  ip: $json.headers['x-forwarded-for']
};

// Naar audit database
await supabase.from('mcp_audit_logs').insert(auditLog);

5. Scoped Permissions

// Permission check
const userPermissions = await getUserPermissions($json.userId);
const requiredPermission = actionPermissionMap[$json.action];

if (!userPermissions.includes(requiredPermission)) {
  throw new Error('Permission denied');
}

Troubleshooting

Probleem: MCP Server start niet

1. Check Node.js versie: node --version (moet 18+ zijn)
2. Controleer pad in configuratie
3. Test server handmatig: node server.js
4. Check logs: tail -f ~/.claude/logs/mcp.log

Probleem: n8n webhook reageert niet

1. Controleer of workflow actief is
2. Test webhook URL met cURL
3. Check n8n logs voor errors
4. Verifieer API key header

Probleem: Claude ziet de tools niet

1. Herstart Claude Code volledig
2. Controleer JSON syntax in config
3. Check MCP server logs
4. Verifieer tools/list response

Conclusie

• Wat is n8n?
• n8n AI Agent Tutorial
• Claude Code Tips en Tricks