resend

To prevent duplicate transactional emails, use an idempotency key when calling the Resend SDK. This ensures that if a request is retried or sent multiple times, the server recognizes the duplicate request and does not send the same email twice.

The best way to verify Resend webhook signatures is by using your RESEND_WEBHOOK_SECRET to validate the incoming payload. This confirms the webhook event was sent by Resend and prevents unauthorized or tampered delivery events from being processed.

Yes, you can send batch transactional emails with template variables using Resend. However, batch sends have specific constraints, such as not supporting attachments or scheduling, so you must structure your payload to accommodate these limitations.

To retrieve the actual email body and attachments from Resend receiving webhooks, you must fetch them separately using the receiving APIs. The webhook itself only provides metadata, requiring a subsequent API call to get the full content.

Yes, you need a RESEND_API_KEY to manage domains, handle delivery events, and authenticate any operational tasks with Resend. Optionally, a RESEND_WEBHOOK_SECRET is required if you are verifying signatures for inbound webhook events.