Human in the Loop

The Human in the Loop block pauses workflow execution and waits for human intervention before continuing. Use it to add approval gates, collect feedback, or gather additional input at critical decision points.

When execution reaches this block, the workflow pauses indefinitely until a human provides input through the approval portal, API, or webhook.

Configuration Options

Paused Output

Defines what data is displayed to the approver. This is the context shown in the approval portal to help them make an informed decision.

Use the visual builder or JSON editor to structure the data. Reference workflow variables using <blockName.output> syntax.

{
  "customerName": "<agent1.content.name>",
  "proposedAction": "<router1.selectedPath>",
  "confidenceScore": "<evaluator1.score>",
  "generatedEmail": "<agent2.content>"
}

Notification

Configures how approvers are alerted when approval is needed. Supported channels include:

Slack - Messages to channels or DMs
Gmail - Email with approval link
Microsoft Teams - Team channel notifications
SMS - Text alerts via Twilio
Webhooks - Custom notification systems

Include the approval URL (<blockId.url>) in your notification messages so approvers can access the portal.

Resume Input

Defines the fields approvers fill in when responding. This data becomes available to downstream blocks after the workflow resumes.

{
  "approved": {
    "type": "boolean",
    "description": "Approve or reject this request"
  },
  "comments": {
    "type": "string",
    "description": "Optional feedback or explanation"
  }
}

Access resume data in downstream blocks using <blockId.resumeInput.fieldName>.

Approval Methods

Approval Portal

Every block generates a unique portal URL (<blockId.url>) with a visual interface showing all paused output data and form fields for resume input. Mobile-responsive and secure.

Share this URL in notifications for approvers to review and respond.

REST API

Programmatically resume workflows:

POST /api/workflows/{workflowId}/executions/{executionId}/resume/{blockId}

{
  "approved": true,
  "comments": "Looks good to proceed"
}

Build custom approval UIs or integrate with existing systems.

Webhook

Add a webhook tool to the Notification section to send approval requests to external systems. Integrate with ticketing systems like Jira or ServiceNow.

Common Use Cases

Content Approval - Review AI-generated content before publishing

Agent → Human in the Loop → API (Publish)

Multi-Stage Approvals - Chain multiple approval steps for high-stakes decisions

Agent → Human in the Loop (Manager) → Human in the Loop (Director) → Execute

Data Validation - Verify extracted data before processing

Agent (Extract) → Human in the Loop (Validate) → Function (Process)

Quality Control - Review AI outputs before sending to customers

Agent (Generate) → Human in the Loop (QA) → Gmail (Send)

Block Outputs

url - Unique URL for the approval portal
resumeInput.* - All fields defined in Resume Input become available after the workflow resumes

Access using <blockId.resumeInput.fieldName>.

Example

Paused Output:

{
  "title": "<agent1.content.title>",
  "body": "<agent1.content.body>",
  "qualityScore": "<evaluator1.score>"
}

Resume Input:

{
  "approved": { "type": "boolean" },
  "feedback": { "type": "string" }
}

Downstream Usage:

// Condition block
<approval1.resumeInput.approved> === true

Condition - Branch based on approval decisions
Variables - Store approval history and metadata
Response - Return workflow results to API callers

Human in the Loop

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