Approval Steps

Approval steps enable human-in-the-loop (HITL) workflows by pausing execution until a designated approver takes action. Use them for scenarios requiring human judgment, data entry, or authorization before proceeding.

Configuration

{
  "id": "manager-approval",
  "type": "approval",
  "name": "Request Manager Approval",
  "config": {
    "approvers": ["user@example.com"],
    "reason": "Invoice #{{input.invoice_id}} for ${{input.amount}} requires approval",
    "timeoutMs": 86400000,
    "notifyChannels": {
      "slack": "#approvals",
      "email": true
    }
  }
}

Field	Type	Required	Description
`id`	string	Yes	Unique step identifier
`type`	string	Yes	Must be `"approval"`
`name`	string	Yes	Human-readable name
`config.approvers`	string[]	Yes	List of approver identifiers (email, user ID, or template)
`config.reason`	string	Yes	Reason shown to approvers explaining what needs approval
`config.timeoutMs`	number	No	Timeout in milliseconds (default: 86400000 / 24 hours)
`config.notifyChannels`	object	No	Channels to send approval notifications

Notification Channels

Configure where approval requests are sent:

{
  "config": {
    "notifyChannels": {
      "slack": "#finance-approvals",
      "slackThreadTs": "{{input.slackEvent.payload.event.ts}}",
      "email": true
    }
  }
}

Field	Type	Description
`slack`	string	Slack channel ID or name for notifications
`slackThreadTs`	string	Thread timestamp to reply in (for threaded conversations)
`email`	boolean	Whether to send email notifications

Slack Threading

Use slackThreadTs to post approval requests as thread replies, keeping conversations organized:

{
  "id": "ask-for-input",
  "type": "approval",
  "config": {
    "approvers": ["{{input.slackEvent.payload.event.user}}"],
    "reason": "Please provide additional details",
    "notifyChannels": {
      "slack": "{{input.slackEvent.payload.event.channel}}",
      "slackThreadTs": "{{input.slackEvent.payload.event.ts}}",
      "email": false
    }
  }
}

Input Types

Control how approvers interact with the approval request:

{
  "config": {
    "inputType": "text",
    "inputLabel": "Amount",
    "inputPlaceholder": "Enter the invoice amount",
    "approveLabel": "Submit",
    "rejectLabel": "Cancel"
  }
}

Field	Type	Default	Description
`inputType`	string	`"buttons"`	Input type: `"buttons"`, `"text"`, or `"both"`
`inputLabel`	string	-	Label for text input field
`inputPlaceholder`	string	-	Placeholder text for text input
`approveLabel`	string	`"Approve"`	Custom label for approve/submit button
`rejectLabel`	string	`"Reject"`	Custom label for reject/cancel button

Button Mode (Default)

Standard approve/reject buttons:

{
  "config": {
    "inputType": "buttons",
    "approveLabel": "Approve Request",
    "rejectLabel": "Deny Request"
  }
}

Text Input Mode

Collect text input from approvers via a modal:

{
  "config": {
    "inputType": "text",
    "inputLabel": "Invoice Amount",
    "inputPlaceholder": "Enter amount (e.g., 5000)",
    "approveLabel": "Enter Input"
  }
}

When inputType is "text", clicking the approve button opens a Slack modal for text entry. The entered value is available in the step output.

Both Mode

Show both approve/reject buttons and a text input option:

{
  "config": {
    "inputType": "both",
    "inputLabel": "Notes",
    "inputPlaceholder": "Add optional notes",
    "approveLabel": "Approve",
    "rejectLabel": "Reject"
  }
}

Output

Approval steps return information about the decision:

{
  "decision": {
    "approved": true,
    "approvedBy": "user@example.com",
    "approvedAt": "2024-01-15T10:30:00Z",
    "reason": "Looks good, approved."
  }
}

Field	Description
`decision.approved`	Whether the request was approved (`true`) or rejected (`false`)
`decision.approvedBy`	Identifier of the user who made the decision
`decision.approvedAt`	ISO 8601 timestamp of the decision
`decision.reason`	Text input provided by the approver (if `inputType` includes text)

Common Patterns

Amount-Based Approval Routing

Route to different approvers based on amount:

{
  "steps": [
    {
      "id": "check-amount",
      "type": "condition",
      "config": {
        "conditions": {
          "left": "{{input.amount}}",
          "operator": "gt",
          "right": "10000"
        },
        "then": ["executive-approval"],
        "else": ["manager-approval"]
      }
    },
    {
      "id": "executive-approval",
      "type": "approval",
      "config": {
        "approvers": ["cfo@company.com"],
        "reason": "High-value transaction: ${{input.amount}} requires executive approval",
        "notifyChannels": {
          "slack": "#executive-approvals",
          "email": true
        }
      }
    },
    {
      "id": "manager-approval",
      "type": "approval",
      "config": {
        "approvers": ["{{input.manager_email}}"],
        "reason": "Transaction of ${{input.amount}} requires manager approval",
        "notifyChannels": {
          "slack": "#manager-approvals",
          "email": true
        }
      }
    }
  ]
}

Sequential Multi-Level Approval

Require approval from multiple levels:

{
  "steps": [
    {
      "id": "manager-approval",
      "type": "approval",
      "config": {
        "approvers": ["{{input.manager}}"],
        "reason": "Step 1/2: Manager approval for {{input.request_type}}",
        "notifyChannels": { "slack": "#approvals" }
      }
    },
    {
      "id": "check-manager-decision",
      "type": "condition",
      "config": {
        "conditions": {
          "left": "{{steps.manager-approval.decision.approved}}",
          "operator": "eq",
          "right": "true"
        },
        "then": ["director-approval"],
        "else": ["notify-rejection"]
      }
    },
    {
      "id": "director-approval",
      "type": "approval",
      "config": {
        "approvers": ["{{input.director}}"],
        "reason": "Step 2/2: Director approval for {{input.request_type}}",
        "notifyChannels": { "slack": "#approvals" }
      }
    }
  ]
}

Data Collection in Loops

Collect user input across multiple iterations:

{
  "steps": [
    {
      "id": "setup",
      "type": "transform",
      "config": {
        "operation": "map",
        "data": { "iterations": [1, 2, 3] }
      }
    },
    {
      "id": "collection-loop",
      "type": "loop",
      "config": {
        "collection": "{{steps.setup.iterations}}",
        "itemVariable": "iteration",
        "steps": ["collect-value", "process-value"]
      }
    },
    {
      "id": "collect-value",
      "type": "approval",
      "config": {
        "approvers": ["{{input.slackEvent.payload.event.user}}"],
        "reason": "Iteration {{loop.iteration}}: Enter a value to process",
        "inputType": "text",
        "inputLabel": "Value",
        "inputPlaceholder": "Enter a number",
        "approveLabel": "Submit",
        "notifyChannels": {
          "slack": "{{input.slackEvent.payload.event.channel}}",
          "slackThreadTs": "{{input.slackEvent.payload.event.ts}}"
        }
      }
    },
    {
      "id": "process-value",
      "type": "code",
      "config": {
        "action": "runCode",
        "code": "return { value: parseFloat(input.userInput) || 0 };",
        "input": {
          "userInput": "{{steps.collect-value.decision.reason}}"
        }
      }
    }
  ]
}

Slack-Triggered Approval with Threading

Handle approvals from Slack conversations:

{
  "name": "Slack Approval Workflow",
  "triggerConfig": {
    "type": "slack_event",
    "eventType": "message",
    "channelTypes": ["channel"],
    "keywords": ["request approval"]
  },
  "steps": [
    {
      "id": "acknowledge",
      "type": "slack",
      "config": {
        "action": "send_message",
        "channel": "{{input.slackEvent.payload.event.channel}}",
        "text": "Processing your request...",
        "thread_ts": "{{input.slackEvent.payload.event.ts}}"
      }
    },
    {
      "id": "get-approval",
      "type": "approval",
      "config": {
        "approvers": ["manager@company.com"],
        "reason": "Approval requested by <@{{input.slackEvent.payload.event.user}}>: {{input.slackEvent.payload.event.text}}",
        "notifyChannels": {
          "slack": "{{input.slackEvent.payload.event.channel}}",
          "slackThreadTs": "{{input.slackEvent.payload.event.ts}}"
        }
      }
    },
    {
      "id": "respond",
      "type": "slack",
      "config": {
        "action": "send_message",
        "channel": "{{input.slackEvent.payload.event.channel}}",
        "text": "Your request was {{#if steps.get-approval.decision.approved}}approved{{else}}rejected{{/if}} by {{steps.get-approval.decision.approvedBy}}",
        "thread_ts": "{{input.slackEvent.payload.event.ts}}"
      }
    }
  ]
}

Timeout Handling

When an approval times out:

The step completes with a timeout status
The workflow can handle this in subsequent condition steps

{
  "steps": [
    {
      "id": "request-approval",
      "type": "approval",
      "config": {
        "approvers": ["approver@company.com"],
        "reason": "Urgent: Requires response within 1 hour",
        "timeoutMs": 3600000
      }
    },
    {
      "id": "check-response",
      "type": "condition",
      "config": {
        "conditions": {
          "left": "{{steps.request-approval.decision.approved}}",
          "operator": "exists"
        },
        "then": ["process-decision"],
        "else": ["handle-timeout"]
      }
    }
  ]
}

Best Practices

Clear Approval Reasons

Provide context so approvers can make informed decisions:

{
  "reason": "Invoice #{{input.invoice_id}} from {{input.vendor_name}} for ${{input.amount}} (due: {{input.due_date}})"
}

Appropriate Timeouts

Set timeouts based on urgency:

Scenario	Timeout	Milliseconds
Urgent approval	1 hour	`3600000`
Same-day approval	8 hours	`28800000`
Standard approval	24 hours	`86400000`
Extended review	72 hours	`259200000`

Thread Continuity

For Slack-triggered workflows, maintain thread context:

{
  "notifyChannels": {
    "slack": "{{input.slackEvent.payload.event.channel}}",
    "slackThreadTs": "{{input.slackEvent.payload.event.ts}}"
  }
}

Troubleshooting

Approval Not Received

Check approvers list - Ensure at least one valid approver is specified
Verify channel access - Bot must have access to notification channels
Check timeout - Approval may have expired

Verify inputType - Must be "text" or "both" for modal
Check connection - Slack connection must be valid
Ensure bot permissions - Bot needs appropriate scopes

Loop Iterations Not Waiting

Each iteration within a loop creates its own approval waitpoint. Ensure:

Loop concurrency is set to 1 for sequential processing
Each iteration waits for user response before continuing

Next Steps

Wait Steps

Timed delays and pauses

Condition Steps

Branching based on approval decisions

Slack Triggers

Trigger workflows from Slack events

Approval Steps

Wait Steps

Condition Steps

Slack Triggers

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