Loopman n8n Community Node

Loopman is a human-in-the-loop automation platform that allows you to seamlessly integrate human decision-making into your automated workflows.

This community node for n8n enables you to send messages to humans and wait for their responses within your n8n workflows.

🚀 Quick Start

Installation

npm install n8n-nodes-loopman

Configuration

1. Get your API key from loopman.ai
2. In n8n, add a Loopman credential with your API key
3. Add the Loopman node to your workflow

Usage

The Loopman node performs polling-only operations to wait for human validation on tasks created by the MCP Client.

Workflow Setup

1. MCP Client Node (upstream): Creates a task with the workflow's external reference
2. Loopman Node (this node): Automatically retrieves the task using workflowId and executionId, then polls for human decision
3. Output Routes: Routes the workflow based on the human decision (Approved, Rejected, Needs Changes)

Note: The Loopman node automatically finds the task created by the MCP Client using the n8n workflow and execution identifiers. No manual configuration needed!

Key Features

• Polling-Only: No task creation, only waits for decisions on existing tasks
• MCP Integration: Requires MCP Client node upstream to create tasks
• Server-Managed Configuration: Polling interval and timeout are retrieved from the task
• Automatic Routing: Routes to different outputs based on human decision

For detailed MCP setup instructions, see MCP Client Setup Guide.

🤖 LLM Configuration (Recommended)

When using the Loopman node with AI models (OpenAI, Claude, etc.), we recommend specific configurations to ensure optimal performance and consistent output formatting.

Temperature Settings

Recommended: 0.1 for consistent, deterministic behavior

• 0.0 - Maximum determinism (may be too rigid)
• 0.1 - Very deterministic, excellent for structured tasks ✅ RECOMMENDED
• 0.3 - Good balance for most use cases
• 0.7 - Default value (may cause formatting issues)

Complete LLM Configuration

// OpenAI Chat Model Configuration
{
  "model": "gpt-4o-mini",
  "temperature": 0.1,           // Very deterministic
  "topP": 0.9,                 // Good balance
  "maxTokens": 2000,           // Prevent truncated responses
  "timeout": 30000,            // Appropriate timeout
  "frequencyPenalty": 0.0,     // No frequency penalty
  "presencePenalty": 0.0       // No presence penalty
}

Why These Settings?

• temperature: 0.1 - Ensures consistent JSON formatting and reduces parsing errors
• maxTokens: 2000 - Prevents truncated responses that can cause workflow failures
• topP: 0.9 - Maintains quality while staying deterministic

Common Issues Fixed

• ✅ Prevents duplicate "Action Input" errors in ReAct parsing
• ✅ Ensures consistent JSON formatting for MCP tools
• ✅ Reduces workflow failures from truncated responses
• ✅ Improves reliability of human-in-the-loop decisions

📦 Installation Methods

Local n8n Instance

Option 1: Via npm (Recommended)

# In your n8n instance directory
npm install n8n-nodes-loopman

# Or install a specific version
npm install [email protected]

Option 2: Development with npm link

# In your loopman-n8n-connector project
npm link

# In your n8n instance directory
npm link n8n-nodes-loopman

Docker Installation

Add to your docker-compose.yml:

version: "3.8"
services:
  n8n:
    image: n8nio/n8n
    ports:
      - "5678:5678"
    environment:
      - N8N_BASIC_AUTH_ACTIVE=true
      - N8N_BASIC_AUTH_USER=admin
      - N8N_BASIC_AUTH_PASSWORD=password
    volumes:
      - n8n_data:/home/node/.n8n
    command: >
      sh -c "
        npm install n8n-nodes-loopman &&
        n8n start
      "

volumes:
  n8n_data:

n8n Cloud

• ❌ Not yet available - Currently under review by n8n team
• ⏳ Coming soon - Will be available in the n8n marketplace once approved

🔧 After Installation

1. Restart n8n:

   # Local installation
   n8n restart
   
   # Docker
   docker-compose restart n8n

2. Verify installation:

   • Open n8n in your browser
   • Go to Nodes → Community Nodes
   • Search for "Loopman"
   • The node should appear in the list

3. Use the connector:

   • Create a new workflow
   • Add a node
   • Search for "Loopman"
   • Configure with your credentials

For detailed installation instructions, see Installation Guide.

🛠️ Development

Quick Start

# Setup (first time only)
npm run setup

# Start development environment (isolated n8n instance)
npm run start:dev

# Stop all n8n processes
npm run stop

# Clean development data (if needed)
npm run clean:dev

This launches:

• TypeScript compiler in watch mode
• Isolated n8n instance (no conflicts with global n8n)
• Node.js debugger on port 9230 with TypeScript source maps
• Fresh database (no migration issues)

Debug TypeScript Directly

1. Start development: npm run start:dev
2. In VS Code: Run and Debug → Debug n8n Connector (TypeScript)
3. Set breakpoints directly in your .ts files
4. Debug with full TypeScript support!

Manual Development

# Install and build
npm install
npm run build
npm link

# Watch TypeScript changes
npm run dev

# In another terminal, start n8n
N8N_CUSTOM_EXTENSIONS=$(pwd)/dist n8n start

📋 Features

• ✅ Polling-only workflow - Wait for human validation on tasks created by MCP Client
• ✅ Automatic routing - Route workflow based on human decision (Approved/Rejected/Needs Changes)
• ✅ MCP Client integration - Seamless integration with AI agent workflows
• ✅ Server-managed configuration - Polling interval and timeout retrieved from task
• ✅ TypeScript support - Full type safety and IntelliSense
• ✅ Debugging support - Debug directly in TypeScript with source maps
• ✅ Docker ready - Easy deployment with Docker Compose
• ✅ npm package - Install via npm for easy distribution

🔗 Links

• Website: loopman.ai
• Documentation: docs.loopman.ai
• npm Package: n8n-nodes-loopman
• GitHub Repository: Loopman-AI/n8n-loopman-connector

📞 Support

• Email: [email protected]
• Issues: GitHub Issues
• Documentation: docs.loopman.ai

📄 License

MIT License - see LICENSE file for details.

Made with ❤️ by the Loopman Team

EXECUTION PROTOCOL - FOLLOW THESE STEPS STRICTLY IN THIS EXACT ORDER:

1️⃣ INITIALIZATION:
   - FIRST, call the MCP tool exactly as follows (single line JSON):
     {"action":"getHumanGuidelines","params":{"workflow_id":"{{ $workflow.id }}"}}
   - Do not proceed until these guidelines have been successfully loaded.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

2️⃣ AGENT ACTION:

[Core of your Agent Prompt: email classification, reasoning, JSON output, etc.]

Apply the retrieved guidelines and decision rules to ensure your proposed output fully complies with policy and workflow expectations.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

3️⃣ SUBMISSION 🚨 MANDATORY FINAL STEP 🚨:
   ⛔ YOU MUST CALL submitForHumanReview TO COMPLETE YOUR TASK ⛔

   - After completing your reasoning and generating your final result, you MUST call the MCP tool `submitForHumanReview`
   - This is NOT optional - it is a REQUIRED step for EVERY workflow
   - You CANNOT provide a final answer without calling submitForHumanReview first
   - Do NOT skip this step under any circumstances
   - The tool description will show all required and optional fields
   - Structure your submission as if writing an email to your supervisor for decision approval
   - The reviewer may not have full context, so provide clear explanations and supporting evidence

⚠️ CRITICAL RULES:
- The order must always be: `getHumanGuidelines` → reasoning → `submitForHumanReview` (NO EXCEPTIONS)
- Use workflow Id = {{ $workflow.id }} and execution Id = {{ $execution.id }} (automatically added by the system)
- Only valid JSON (single line) will be executed — any text, markdown, or explanation outside the JSON will cause an error
- Optional fields must be omitted, not left empty
- Always put the entire JSON on one line. Never use line breaks in Action Input
- If you provide a final answer without calling submitForHumanReview first, you have FAILED the task