n8n-mcp/README.md

n8n-mcp

Integration between n8n workflow automation and Model Context Protocol (MCP). This project provides:

• An MCP server that exposes n8n workflows and operations to AI assistants
• A custom n8n node for connecting to MCP servers from within workflows

Features

• MCP Server: Expose n8n workflows as tools, resources, and prompts for AI assistants
• n8n Node: Connect to any MCP server from n8n workflows
• Bidirectional Integration: Use AI capabilities in n8n and n8n automation in AI contexts
• Node Source Extraction: Extract source code from any n8n node, including AI Agent nodes
• Authentication: Secure token-based authentication
• Flexible Transport: Support for WebSocket and stdio connections

Quick Start

Prerequisites

• Node.js 18+
• n8n instance with API access enabled
• MCP-compatible AI assistant (Claude, etc.)

Installation

# Clone the repository
git clone https://github.com/czlonkowski/n8n-mcp.git
cd n8n-mcp

# Install dependencies
npm install

# Copy environment configuration
cp .env.example .env

# Configure your n8n API credentials
# Edit .env with your n8n instance details

Running the MCP Server

# Build the project
npm run build

# Start the MCP server
npm start

For development:

npm run dev

Configuration

Environment Variables

Create a .env file based on .env.example:

# MCP Server Configuration
MCP_SERVER_PORT=3000
MCP_SERVER_HOST=localhost

# n8n Configuration
N8N_API_URL=http://localhost:5678
N8N_API_KEY=your-n8n-api-key

# Authentication
MCP_AUTH_TOKEN=your-secure-token

# Logging
LOG_LEVEL=info

Usage

Using the MCP Server with Claude

Add the server to your Claude configuration:

{
  "mcpServers": {
    "n8n": {
      "command": "node",
      "args": ["/path/to/n8n-mcp/dist/index.js"],
      "env": {
        "N8N_API_URL": "http://localhost:5678",
        "N8N_API_KEY": "your-api-key"
      }
    }
  }
}

Available MCP Tools

• execute_workflow - Execute an n8n workflow by ID
• list_workflows - List all available workflows
• get_workflow - Get details of a specific workflow
• create_workflow - Create a new workflow
• update_workflow - Update an existing workflow
• delete_workflow - Delete a workflow
• get_executions - Get workflow execution history
• get_execution_data - Get detailed execution data
• get_node_source_code - Extract source code of any n8n node
• list_available_nodes - List all available n8n nodes

Using the n8n MCP Node

1. Copy the node files to your n8n custom nodes directory
2. Restart n8n
3. The MCP node will appear in the nodes panel
4. Configure with your MCP server credentials
5. Select operations: Call Tool, List Tools, Read Resource, etc.

Example n8n Workflow

{
  "name": "MCP AI Assistant",
  "nodes": [
    {
      "name": "MCP",
      "type": "mcp",
      "parameters": {
        "operation": "callTool",
        "toolName": "generate_text",
        "toolArguments": "{\"prompt\": \"Write a summary\"}"
      }
    }
  ]
}

Architecture

Project Structure

n8n-mcp/
├── src/
│   ├── mcp/          # MCP server implementation
│   ├── n8n/          # n8n node implementation
│   ├── utils/        # Shared utilities
│   └── types/        # TypeScript type definitions
├── tests/            # Test files
└── dist/             # Compiled output

Key Components

• MCP Server: Handles MCP protocol requests and translates to n8n API calls
• n8n API Client: Manages communication with n8n instance
• Bridge Layer: Converts between n8n and MCP data formats
• Authentication: Validates tokens and manages access control

Development

Running Tests

npm test

Building

npm run build

Type Checking

npm run typecheck

API Reference

MCP Tools

execute_workflow

Execute an n8n workflow by ID.

Parameters:

• workflowId (string, required): The workflow ID
• data (object, optional): Input data for the workflow

list_workflows

List all available workflows.

Parameters:

• active (boolean, optional): Filter by active status
• tags (array, optional): Filter by tags

get_node_source_code

Extract source code of any n8n node.

Parameters:

• nodeType (string, required): The node type identifier (e.g., @n8n/n8n-nodes-langchain.Agent)
• includeCredentials (boolean, optional): Include credential type definitions if available

list_available_nodes

List all available n8n nodes in the system.

Parameters:

• category (string, optional): Filter by category (e.g., AI, Data Transformation)
• search (string, optional): Search term to filter nodes

MCP Resources

• workflow://active - List of active workflows
• workflow://all - List of all workflows
• execution://recent - Recent execution history
• credentials://types - Available credential types
• nodes://available - Available n8n nodes
• nodes://source/{nodeType} - Source code of specific n8n node

MCP Prompts

• create_workflow_prompt - Generate workflow creation prompts
• debug_workflow_prompt - Debug workflow issues
• optimize_workflow_prompt - Optimize workflow performance
• explain_workflow_prompt - Explain workflow functionality

Troubleshooting

Common Issues

1. Connection refused: Ensure n8n is running and API is enabled
2. Authentication failed: Check your API key in .env
3. Workflow not found: Verify workflow ID exists in n8n
4. MCP connection failed: Check server is running and accessible

Debug Mode

Enable debug logging:

LOG_LEVEL=debug

Special Features

AI Agent Node Extraction

The MCP server can extract source code from n8n nodes, particularly useful for AI Agent nodes:

# Test AI Agent extraction
./scripts/test-ai-agent-extraction.sh

# Or use the standalone test
node tests/test-mcp-extraction.js

This feature allows AI assistants to:

• Understand n8n node implementations
• Generate compatible code
• Debug workflow issues
• Create custom variations

Docker Volumes for Node Access

When running in Docker, mount n8n's node_modules for source extraction:

volumes:
  - n8n_modules:/usr/local/lib/node_modules/n8n/node_modules:ro

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests
5. Submit a pull request

License

ISC License - see LICENSE file for details

Support

• Issues: https://github.com/czlonkowski/n8n-mcp/issues
• n8n Documentation: https://docs.n8n.io
• MCP Specification: https://modelcontextprotocol.io