Resend

Agents can work with your Resend account — checking delivery status, inspecting domains and audiences, and, where you permit it, sending email.

Warning: This connector can reach a real sending pipeline. Mail sent from Resend goes to real inboxes, counts against your plan, and affects your domain's sending reputation. Do not verify this connector by sending a message.

Resend is for programmatic email from your own domains. If you want an agent to have its own inbox and treat conversations as tasks, that is AgentMail. If you want an agent to read your personal mailbox, that is Gmail.

Before you connect

  • A Resend account with access to the domains you want agents to work with.
  • Verified sending domains, if sending is in scope. Resend requires domain verification through DNS before it will send from an address, and this connector does not change that.

Connect Resend

  1. Open Connectors and select Resend.
  2. Read the access line above the main button. It says who the connection signs in as and which agents can use it. To pick a different identity, narrow the agents, or use another sign-in method, select Change.
  3. Select Sign in with Resend and complete browser sign-in.

Paperclip registers its client automatically, so there is nothing to configure in a developer console.

Choose access

Reach is the authorizing Resend account's: its domains, audiences, and delivery history.

Separate the operations clearly, because they differ enormously in consequence:

Operation Consequence
Reading delivery status, domains, audiences Nothing leaves the building
Managing audiences and contacts Changes who is on a mailing list
Sending email Real mail to real people, immediately and irreversibly

Danger: Keep send actions Off, or Ask first at the very least. An agent that can send mail unsupervised can email your customers. There is no recall, and a mistake affects your domain reputation as well as the recipients.

Audience changes deserve care too — removing a contact loses a subscription record, and adding one may have consent implications. See Set action permissions.

Try it

Verify with a read:

List the verified sending domains on the Resend account and tell me the delivery status of the most recent email. Do not send anything.

Compare against the Resend dashboard. This confirms the credential and shows you the domain configuration at the same time, with nothing delivered.

Note: A verified domain means Resend has confirmed its DNS, not that this credential may send from it. Whether an agent can actually send depends on the API key's own permissions and on the send action's setting in Paperclip — listing domains tells you neither. Keep those three things separate when you reason about what this connection can do.

If you eventually need to confirm sending, send to an address you personally control, from a domain you own, and only once you have decided the agent should have that capability.

Note: Illustrative task, not a recorded test result.

Troubleshooting and limitations

Problem Likely cause Fix
No domains are listed The account has none, or none are verified Add and verify a domain in Resend
Sending is refused The domain is not verified, or the send action is Off Verify the domain in Resend; check the Permissions tab
Mail sends but does not arrive Recipient filtering, or domain reputation and DNS records Check Resend's delivery logs and your SPF, DKIM, and DMARC records
An agent emailed someone unexpectedly A send action was set to Allowed Set it to Off, and review what was sent in Resend's logs
Sends are throttled Resend's plan rate limits Check your plan limits
Needs attention The grant was revoked Select Reconnect

Limitations: one Resend account per connection. Domain verification is Resend's and cannot be bypassed. Paperclip cannot recall sent mail.