# Smartletter

> Smartletter is a newsletter platform with AI writing, sending on Amazon SES, an API and an MCP server. The REST API (https://api.smartletter.ai) covers newsletters, contacts, signups, stats and Resend-compatible transactional email.

## Docs

- [Introduction](https://smartletter.ai/docs): Run your newsletter from code or from an AI agent.
- [Authentication](https://smartletter.ai/docs/authentication): API keys and their three levels.
- [Errors](https://smartletter.ai/docs/errors): Error format and names.
- [Limits](https://smartletter.ai/docs/limits): Rate limits, pagination and idempotency.
- [MCP server](https://smartletter.ai/docs/mcp): Connect Claude, ChatGPT or Cursor to your newsletter.

## API reference

- [Emails](https://smartletter.ai/docs/emails): Transactional email, compatible with the Resend API and SDKs.
- [Newsletters](https://smartletter.ai/docs/newsletters): Newsletter issues (campaigns): write, review, test, send, schedule, pause, report.
- [Contacts](https://smartletter.ai/docs/contacts): Subscribers of your newsletters: add, import with cleaning, export, unsubscribe.
- [Signups](https://smartletter.ai/docs/signups): Double opt-in signups from your own site, with a key that is safe in public code.
- [Segments](https://smartletter.ai/docs/segments): Your newsletters (segments) and their topics.
- [Archive](https://smartletter.ai/docs/archive): Public archive of a newsletter's sent issues, and its custom subdomain (tracked links, preferences, archive).
- [Suppressions](https://smartletter.ai/docs/suppressions): Addresses that never receive anything from your workspace.
- [Images](https://smartletter.ai/docs/images): Images for your newsletters, hosted on the Smartletter CDN.
- [Stats](https://smartletter.ai/docs/stats): Audience growth and sending volume.
- [Domains](https://smartletter.ai/docs/domains): Custom sending domains (DKIM, SPF, MX).
- [API keys](https://smartletter.ai/docs/api-keys): Create, list, rename and revoke API keys.
- [Logs](https://smartletter.ai/docs/logs): The last API requests of your workspace.
- [Usage](https://smartletter.ai/docs/usage): Plan limits and what you used.
- [Meta](https://smartletter.ai/docs/meta): This API's own description.

## Optional

- [Full reference for LLMs](https://smartletter.ai/llms-full.txt): every guide and route in one Markdown file
- [OpenAPI 3.1](https://api.smartletter.ai/openapi.json)