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The Resend app connects your StellarTools organization to Resend, letting you send transactional emails when things happen to your customers — payments, subscriptions, refunds, and more. With it you can:
  • Send emails triggered by any StellarTools event
  • Auto-sync new customers to a Resend audience
  • Map each event type to a Resend email template
  • View a live email log and delivery stats inside the dashboard

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Supported events

The app can trigger emails on any of the following StellarTools events:
EventWhen it fires
customer.createdA new customer is added
customer.updatedA customer’s details change
customer.deletedA customer is removed
payment_method.createdA wallet is linked to a customer
payment_method.deletedA wallet is removed
checkout.createdA checkout session is opened
payment.pendingA payment is initiated
payment.confirmedA payment is confirmed on-chain
payment.failedA payment fails
refund.succeededA refund is processed
refund.failedA refund attempt fails
subscription.createdA subscription starts
subscription.updatedA subscription changes
subscription.canceledA subscription is canceled

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Connect your account

  1. Open the Resend app from the StellarTools Marketplace.
  2. Enter your Resend API key (starts with re_). The app validates it against your Resend account.
  3. Choose a sending domain. If you have a verified domain in Resend, you can pick it here and set a custom from prefix (e.g. noreply@yourdomain.com). Without a verified domain, emails go out via onboarding@resend.dev, which can only reach addresses registered in your Resend account.
  4. Click Connect. The app is now active.
To verify a sending domain, go to resend.com/domains.

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Notification rules

Once connected, open the Notification rules section in the app dashboard. For each event type, you can assign a Resend email template. When that event fires in StellarTools, Resend sends the matched template to the customer. Leave an event set to None to disable emails for it.

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Contact sync

Enable Contact sync to automatically add new StellarTools customers to your Resend audience when customer.created fires. Toggle it off to stop syncing.

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Disconnect

Click Disconnect in the top-right of the app dashboard. This removes your API key and pauses all email delivery.

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Examples

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Payment confirmed email

Send a receipt when a customer’s payment goes through.
  1. Create an email template in Resend for payment confirmations.
  2. In the Resend app, open Notification rules and assign that template to payment.confirmed.

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Subscription welcome email

Send a welcome email when a customer starts a subscription.
  1. Create an email template in Resend.
  2. Assign it to subscription.created in Notification rules.

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Failed payment alert

Notify a customer when their payment fails so they can retry.
  1. Create an email template in Resend for payment failures.
  2. Assign it to payment.failed in Notification rules.

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Refund confirmation

Let customers know their refund was processed.
  1. Create a refund confirmation template in Resend.
  2. Assign it to refund.succeeded in Notification rules.