Resend

Resend is a modern email delivery platform for developers.

Overview

Resend is a transactional email API built for developer-driven workflows. It handles outbound deliverability, domain verification, and audience management without requiring you to run your own SMTP infrastructure. Teams use it for order confirmations, onboarding sequences, alert emails, and any programmatic message that needs to land reliably.

In Spojit, Resend is most often used as the outbound channel at the end of a workflow. You fetch data from another system (Shopify, NetSuite, MongoDB), shape the message body with an AI step or template, and send via send-email or send-batch-emails. The contact and domain tools let you keep audiences in sync without leaving the workflow.

What You Can Do

The Resend connector exposes these tools:

create-contact - add a contact to an audience.
delete-contact - remove a contact from an audience.
get-contact - fetch a contact by id or email.
get-domain - fetch a sending domain and its verification status.
get-email - fetch the delivery details of a sent email.
list-contacts - list contacts in an audience.
list-domains - list every sending domain on the account.
list-emails - list recent emails sent through the account.
raw-request - call any Resend API endpoint directly.
send-batch-emails - send up to 100 emails in a single request.
send-email - send a single transactional email.
update-contact - update a contact's fields or subscription status.
verify-domain - trigger DNS re-verification for a sending domain.

Authentication

Resend uses an API key. Generate one in the Resend dashboard at Dashboard -> API Keys. You can scope keys to Full access or Sending access; for workflows that only send mail, use a sending-only key. Each key is tied to a domain; make sure the domain you send from is verified before going live.

Setting Up Your Connection

In Resend, open Dashboard -> Domains and verify the domain you plan to send from.
Go to Dashboard -> API Keys and create a new key with the appropriate scope.
Copy the key value (shown once).
In Spojit, go to Connections from the sidebar.
Click + Add Connection and search for Resend.
Paste the API key, name the connection (for example, Resend - Production) and click Save.

Using in a Workflow

Use Direct Mode for predictable transactional sends where the body comes from a template or an upstream step. Use Agent Mode when an AI step composes the subject and body from context. For high-volume sends (newsletters, weekly digests), batch up to 100 recipients with send-batch-emails instead of looping single sends.

Tips

Verify your sending domain before testing; unverified domains can only send to your own account email.
Use send-batch-emails for any send larger than five recipients; it counts as one API call against rate limits.
Resend supports React Email templates, but the connector accepts plain HTML and text bodies, so render templates upstream.
The get-email tool reports delivery, bounce, and complaint status, useful for follow-up branches.

Common Pitfalls

The from address must match a verified domain on the account; sending from a generic Gmail address will fail.
Resend's default rate limit is 10 requests per second; batch where possible.
Audience contacts are scoped to a specific audience id; the same email in two audiences is two contact records.
Domain DNS changes can take time to propagate; call verify-domain after editing DNS rather than waiting for the daily check.

Common Use Cases

For technical API details and field specifications, see the Resend connector documentation.