Human In The Loop Block

The Human In The Loop (HITL) block introduces human oversight into automated workflows. It pauses execution and waits for a person to review data, make decisions, or take action before the workflow continues.

Key Features

• Pause and Resume - Workflow halts at the HITL block and resumes when a human responds
• Multi-Channel Notifications - Alert reviewers via Slack, Email, MS Teams, or custom webhooks
• Interactive Decisions - Present options like Approve, Reject, Escalate, or custom actions
• Data Presentation - Display relevant context to help humans make informed decisions
• Configurable Timeouts - Set deadlines with automatic fallback actions
• Audit Trail - Track who responded, when, and what action they took
• Parallel Reviews - Request input from multiple reviewers simultaneously

When to Use Human In The Loop

Configuration

Setup Guide

Step 1: Add the HITL Block

1. Open your workflow in the editor
2. Navigate to Logic blocks
3. Drag the Human In The Loop block onto your canvas
4. Connect it in the workflow where human review is needed

Step 2: Configure Notifications

1. Select your notification platform (Slack, Email, Teams)
2. Enter the channel or recipient details
3. Compose a clear, actionable title
4. Add description with context

Step 3: Define Review Data

Structure the data reviewers will see:

{
  "summary": "{{ai.summary}}",
  "confidence": "{{ai.confidence}}%",
  "originalInput": "{{user.query}}",
  "suggestedAction": "{{ai.recommendation}}"
}

Step 4: Set Action Options

Define available decisions:

• Approve - Continue workflow as planned
• Reject - Stop workflow or trigger rejection flow
• Request Changes - Route back for modification
• Escalate - Forward to senior reviewer
• Custom options for your use case

Step 5: Configure Timeout Behavior

1. Set a reasonable timeout (e.g., 4 hours for urgent, 48 hours for routine)
2. Choose fallback action:
   • Execute default action
   • Escalate to another reviewer
   • Cancel workflow
   • Retry notification

Use Case Examples

Content Approval Workflow

AI Generates Content → Human In The Loop → Approve? → Publish

Configuration:
- Title: "Blog Post Ready for Review"
- Description: "New AI-generated content needs approval"
- Data: Post title, content preview, target audience
- Options: Approve, Request Edits, Reject
- Timeout: 24 hours → Auto-escalate to editor

Large Order Verification

Order Received → Check Amount > $10K → Human In The Loop → Process Order

Configuration:
- Title: "Large Order Requires Approval"
- Description: "Order exceeds $10,000 threshold"
- Data: Order ID, customer info, items, total amount
- Options: Approve Order, Hold for Review, Cancel Order
- Timeout: 4 hours → Flag for management review

AI Response Quality Gate

User Query → AI Generate Response → AI Judge → If Low Confidence → Human In The Loop

Configuration:
- Title: "AI Response Needs Human Review"
- Description: "Low confidence score ({{confidence}}%) - please verify"
- Data: User question, AI response, confidence metrics
- Options: Send as-is, Edit and Send, Regenerate
- Timeout: 30 minutes → Escalate to team lead

Financial Transaction Approval

Transaction Created → Risk Score Check → Human In The Loop → Execute Transaction

Configuration:
- Title: "Transaction Approval Required"
- Description: "High-risk transaction flagged for review"
- Data: Transaction details, risk factors, customer history
- Options: Approve, Decline, Request Additional Verification
- Timeout: 2 hours → Auto-decline and notify customer

Output Variables

The HITL block outputs the following data:

Workflow Branching

Use conditional logic after HITL to route based on decisions:

Human In The Loop
    │
    ├── action === "Approve"
    │   └── Continue normal workflow
    │
    ├── action === "Reject"
    │   └── Send rejection notification → End workflow
    │
    ├── action === "Request Changes"
    │   └── Route back to content generation
    │
    └── timedOut === true
        └── Execute fallback action

Integration with Notification Platforms

Slack Integration

• Interactive message with action buttons
• Real-time responses captured automatically
• Supports threading for context
• Can mention specific users or groups

Email Integration

• Clean HTML email with action links
• Secure one-click response tokens
• Mobile-friendly design
• Supports CC/BCC for visibility

Microsoft Teams Integration

• Adaptive cards with interactive elements
• Integrates with Teams approval workflows
• Supports channel or direct messages

Custom Webhook

• Send to any system with REST API
• Include custom headers and authentication
• Handle responses via callback URL

Best Practices

1. Provide Complete Context - Include all information needed to make a decision
2. Set Realistic Timeouts - Balance urgency with reviewer availability
3. Define Clear Actions - Use unambiguous action labels
4. Always Have Fallbacks - Never leave workflows hanging on timeout
5. Track Metrics - Monitor response times and decision patterns
6. Minimize Fatigue - Don't overload reviewers with unnecessary requests
7. Use Appropriate Urgency - Route urgent items to faster channels
8. Document Decisions - Store responses for audit trails
9. Test Notification Flow - Verify alerts reach the right people
10. Consider Time Zones - Account for reviewer availability

Error Handling

Troubleshooting

Notifications not arriving:

• Verify platform credentials are valid
• Check that the bot/integration is added to the channel
• Confirm recipient email addresses are correct

Responses not captured:

• Ensure webhook callback URLs are accessible
• Check that response tokens haven't expired
• Verify the reviewer used the interactive buttons

Workflow stuck waiting:

• Check if timeout is configured
• Verify notification was actually sent (check logs)
• Consider adding manual override capability