Resend for email deliverability
Resend is the developer-first email service in this lineup, and its official server is the top pick for deliverability work. It earns that spot by being the cleanest place for an agent to send a message and then immediately inspect what happened to it: pull the sent record, read its delivery status, and trace a problem back to a specific send.
Deliverability is a tight send-then-check loop, and Resend's server keeps both halves in one connection. The agent fires a test message and reads its outcome without leaving the conversation, which is the core of diagnosing why mail does or does not land.
How Resend fits
The tools that do deliverability work are the sent-message ones: send-email to issue a test or production message, then list-emails to see what has gone out and get-email to retrieve a specific send with its delivery status by ID. For high-volume diagnosis, send-batch-emails issues many at once. On the inbound side, list-received-emails and get-received-email let the agent inspect what actually arrived, useful for confirming a round trip. update-email and cancel-email manage queued sends before they go.
Honest scope: the server's tagline mentions domain management, but this tool set does not expose a domain-verification, DNS, or suppression-list command, so the agent diagnoses through send and delivery-status records rather than reading SPF, DKIM, or a bounce list directly. Mailgun and Postmark are both strong on deliverability with their own analytics emphasis, and Brevo leans toward a hosted contacts-and-campaigns model. Resend ranks first here for the developer-first send-and-inspect loop; reach for a sibling if your diagnosis hinges on authentication records or a suppression API this server does not surface.
Tools you would use
| Tool | What it does |
|---|---|
| send-email | Sends a single transactional email immediately or scheduled, with HTML/text, attachments, CC/BCC, and tags. |
| send-batch-emails | Sends a batch of emails in a single request. |
| list-emails | Lists sent emails. |
| get-email | Retrieves a sent email and its delivery status by ID. |
| update-email | Updates a scheduled email, such as its send time. |
| cancel-email | Cancels a scheduled email before it sends. |
| list-sent-email-attachments | Lists the attachments on a sent email. |
| get-sent-email-attachment | Retrieves a specific attachment from a sent email. |
| list-received-emails | Lists inbound received emails. |
| get-received-email | Retrieves a received email by ID. |
FAQ
- Can Resend's MCP server verify domain authentication or read a suppression list?
- Not with this tool set. It covers sending and reading delivery status through send-email, list-emails, and get-email, plus inbound inspection, but exposes no domain-verification, DNS, or suppression-list command. An agent diagnoses through send and delivery records, so for authentication-record or bounce-list work a sibling may fit better.
- How does an agent diagnose a delivery problem with Resend?
- It sends a test with send-email, then reads the outcome with get-email by ID to see the delivery status, and uses list-emails to scan recent sends for a pattern. Inbound checks run through list-received-emails and get-received-email to confirm a message actually arrived.