Knowledge base
Developers
Everything in the app is also a call your own code can make: send mail, scope keys, hear about events, and drive it from a typed client or an agent.
In this section
Email APISend one message or a hundred per call, now or later, and retry without sending twice.API keysA key per job, limited to the scopes and senders it needs, with every call logged.REST APIA documented HTTP API with issuable, scopable, revocable keys.WebhooksTell your endpoint when mail arrives, instead of making you poll.Typed SDKsA TypeScript client first, then the rest.MCP serverPoint Claude, or any MCP client, at your mailbox.OAuth for third-party clientsApps register themselves and sign in with PKCE, and you choose the workspace, addresses and permissions each one gets.Move from ResendBring your suppressions, audiences, contacts, templates and webhooks across with one key, with a checklist for your domains and API keys.