> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dodopayments.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Loops

> Send transactional emails and manage customer communication through Loops based on Dodo Payments events.

## Introduction

Send transactional emails and manage customer communication automatically when payment events occur. Deliver payment confirmations, subscription updates, and important notifications with Loops' email infrastructure.

<Info>
  This integration requires your Loops API Key for authentication.
</Info>

## Getting Started

<Steps>
  <Step title="Open the Webhook Section">
    In your Dodo Payments dashboard, navigate to <b>Webhooks → + Add Endpoint</b> and expand the integrations dropdown.

    <Frame>
      <img src="https://mintcdn.com/dodopayments/slbAEdrLLwKHfaRf/images/integrations/loops.png?fit=max&auto=format&n=slbAEdrLLwKHfaRf&q=85&s=2d66cf4c1f562427613d7b2704dcc8a3" alt="Add Endpoint and integrations dropdown" style={{ maxHeight: '500px', width: 'auto' }} width="1656" height="940" data-path="images/integrations/loops.png" />
    </Frame>
  </Step>

  <Step title="Select Loops">
    Choose the <b>Loops</b> integration card.
  </Step>

  <Step title="Enter API Key">
    Provide your Loops API Key in the configuration.
  </Step>

  <Step title="Configure Transformation">
    Edit the transformation code to format emails for Loops' API.
  </Step>

  <Step title="Test & Create">
    Test with sample payloads and click <b>Create</b> to activate the email sending.
  </Step>

  <Step title="Done!">
    🎉 Payment events will now automatically trigger transactional emails via Loops.
  </Step>
</Steps>

## Transformation Code Examples

### Payment Confirmation Email

```javascript payment_confirmation.js icon="js" expandable theme={null}
function handler(webhook) {
  if (webhook.eventType === "payment.succeeded") {
    const p = webhook.payload.data;
    webhook.url = "https://api.loops.so/v1/events/send";
    webhook.payload = {
      eventName: "payment_confirmation",
      email: p.customer.email,
      properties: {
        customer_name: p.customer.name,
        payment_id: p.payment_id,
        amount: (p.total_amount / 100).toFixed(2),
        currency: p.currency || "USD",
        payment_method: p.payment_method || "unknown",
        payment_date: new Date(webhook.payload.timestamp).toLocaleDateString()
      }
    };
  }
  return webhook;
}
```

### Subscription Welcome Email

```javascript subscription_welcome.js icon="js" expandable theme={null}
function handler(webhook) {
  if (webhook.eventType === "subscription.active") {
    const s = webhook.payload.data;
    webhook.url = "https://api.loops.so/v1/events/send";
    webhook.payload = {
      eventName: "subscription_welcome",
      email: s.customer.email,
      properties: {
        customer_name: s.customer.name,
        subscription_id: s.subscription_id,
        product_id: s.product_id,
        amount: (s.recurring_pre_tax_amount / 100).toFixed(2),
        frequency: s.payment_frequency_interval,
        next_billing: s.next_billing_date
      }
    };
  }
  return webhook;
}
```

### Payment Failure Notification

```javascript payment_failure.js icon="js" expandable theme={null}
function handler(webhook) {
  if (webhook.eventType === "payment.failed") {
    const p = webhook.payload.data;
    webhook.url = "https://api.loops.so/v1/events/send";
    webhook.payload = {
      eventName: "payment_failed",
      email: p.customer.email,
      properties: {
        customer_name: p.customer.name,
        payment_id: p.payment_id,
        amount: (p.total_amount / 100).toFixed(2),
        error_message: p.error_message || "Payment processing failed",
        retry_link: `https://yourdomain.com/retry-payment/${p.payment_id}`
      }
    };
  }
  return webhook;
}
```

## Tips

* Use descriptive event names for better email template organization
* Include relevant customer properties for personalization
* Set up email templates in Loops dashboard for each event
* Use consistent property naming across events
* Test email delivery before going live

## Troubleshooting

<AccordionGroup>
  <Accordion title="Emails not being sent">
    * Verify API Key is correct and active
    * Check that event names match your Loops templates
    * Ensure recipient email addresses are valid
    * Review Loops sending limits and quotas
  </Accordion>

  <Accordion title="Transformation errors">
    * Validate JSON structure matches Loops API format
    * Check that all required fields are present
    * Ensure event names are properly formatted
    * Verify API key permissions
  </Accordion>
</AccordionGroup>