Setting Up n8n-workflow-builder for Claude Desktop App

Setting Up n8n-workflow-builder for Claude Desktop App

This guide explains how to set up the n8n-workflow-builder for use with Claude Desktop App.

Configuration Steps

1. Find the MCP Configuration Directory

The location of the Claude Desktop App MCP settings file depends on your operating system:

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

2. Create or Edit the Configuration File

Create or edit the `cline_mcp_settings.json` file in the directory mentioned above.

3. Add the n8n-workflow-builder Configuration

Add the following JSON configuration, making sure to replace the placeholder paths and API credentials with your actual values:

{
  "n8n-workflow-builder": {
    "command": "node",
    "args": ["/absolute/path/to/n8n-workflow-builder/build/index.js"],
    "env": {
      "N8N_HOST": "https://your-n8n-instance.com/api/v1/",
      "N8N_API_KEY": "your_n8n_api_key_here",
      "MCP_PORT": "58921"
    },
    "disabled": false,
    "alwaysAllow": [
      "list_workflows",
      "get_workflow",
      "list_executions",
      "get_execution"
    ],
    "autoApprove": [
      "create_workflow",
      "update_workflow",
      "activate_workflow",
      "deactivate_workflow",
      "delete_workflow",
      "delete_execution"
    ]
  }
}

4. Configuration Parameters Explained

• command: The command to run the MCP server (always "node" for this project)
• args: Array of arguments to pass to the command
  • The first argument should be the absolute path to the compiled index.js file
• env: Environment variables to set for the process
  • N8N_HOST: Your n8n API host URL
  • N8N_API_KEY: Your n8n API key
  • MCP_PORT: (Optional) Custom port for the MCP server (default: 3456)
• disabled: Set to false to enable the tool
• alwaysAllow: Tools that are allowed without asking for permission (read operations)
• autoApprove: Tools that require permission only on first use

5. Important Notes

• All logs from stdout have been removed from the codebase for compatibility with the Claude Desktop App
• The absolute path to index.js must be correct for your system
• You must restart Claude Desktop App after modifying the configuration file
• All read operations (list_workflows, get_workflow) are safe to put in alwaysAllow
• Write operations should be in autoApprove or left out entirely for maximum security
• If you encounter port conflicts, use the MCP_PORT parameter to set a different port (like 58921)
• Starting with version 0.7.2, the server will automatically handle port conflicts by gracefully continuing if another instance is already running on the specified port

Troubleshooting Common Issues

Port Conflicts

If you see errors about "address already in use" in your logs:

1. Use a non-standard high port (e.g., 58921) in your configuration: