---
title: "Developers"
description: "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."
url: "https://openemail.uk/docs/knowledge/developers"
area: "Knowledge base"
category: "Developers"
---

# 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 API](https://openemail.uk/docs/knowledge/developers/email-api.md): Send one message or a hundred per call, now or later, and retry without sending twice.
- [API keys](https://openemail.uk/docs/knowledge/developers/api-keys.md): A key per job, limited to the scopes and senders it needs, with every call logged.
- [REST API](https://openemail.uk/docs/knowledge/developers/api.md): A documented HTTP API with issuable, scopable, revocable keys.
- [Webhooks](https://openemail.uk/docs/knowledge/developers/webhooks.md): Tell your endpoint when mail arrives, instead of making you poll.
- [Typed SDKs](https://openemail.uk/docs/knowledge/developers/sdk.md): A TypeScript client first, then the rest.
- [MCP server](https://openemail.uk/docs/knowledge/developers/mcp.md): Point Claude, or any MCP client, at your mailbox.
- [OAuth for third-party clients](https://openemail.uk/docs/knowledge/developers/oauth.md): Apps register themselves and sign in with PKCE, and you choose the workspace, addresses and permissions each one gets.
- [Move from Resend](https://openemail.uk/docs/knowledge/developers/switch-from-resend.md): Bring your suppressions, audiences, contacts, templates and webhooks across with one key, with a checklist for your domains and API keys.