> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sendrealm.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> General introduction for the Sendrealm API

The Sendrealm API lets you send emails and push notifications, manage contacts, organize your contacts with audiences and topics, store versioned templates, and run event-driven automations.

## Base URL

```text theme={null}
https://api.sendrealm.com
```

## Authentication

All API endpoints are authenticated using API keys. Create an API key from the Sendrealm dashboard, then include it in the `Authorization` header for each request.

```bash theme={null}
Authorization: Bearer {apiKey}
```

## Resources

<CardGroup cols={2}>
  <Card title="Emails" icon="envelope" href="/api-reference/endpoint/create">
    Send transactional or product emails through the API.
  </Card>

  <Card title="Push notifications" icon="bell" href="/api-reference/endpoint/send-push-notification">
    Send notifications to push devices, contacts, external IDs, or audiences.
  </Card>

  <Card title="Audiences" icon="users" href="/api-reference/endpoint/create-audience">
    Create, list, update, and delete audiences.
  </Card>

  <Card title="Audience properties" icon="list-tree" href="/api-reference/endpoint/create-audience-property">
    Define custom fields for contact and audience data.
  </Card>

  <Card title="Contacts" icon="address-book" href="/api-reference/endpoint/create-contact">
    Create, list, update, and delete contacts.
  </Card>

  <Card title="Audience memberships" icon="user-plus" href="/api-reference/endpoint/attach-contact-to-audience">
    Add contacts to audiences or remove them.
  </Card>

  <Card title="Events" icon="wave-pulse" href="/api-reference/endpoint/events">
    Ingest customer events and react to Sendrealm system events.
  </Card>

  <Card title="Templates" icon="layer-group" href="/api-reference/endpoint/templates">
    Create, publish, restore, and reuse email or push templates.
  </Card>

  <Card title="Automations" icon="diagram-project" href="/api-reference/endpoint/automations">
    Create automation drafts, publish them, and inspect their runs.
  </Card>

  <Card title="Topics" icon="toggle-on" href="/api-reference/endpoint/topics">
    Manage reusable topic subscriptions for audience preferences.
  </Card>
</CardGroup>

## Status codes

The Sendrealm API uses HTTP status codes to indicate the result of each request.

| Status Code | Description                            |
| ----------- | -------------------------------------- |
| 200         | Successful request.                    |
| 201         | Resource created or notification sent. |
| 400         | Invalid request parameters.            |
| 401         | API key was missing or invalid.        |
| 404         | Resource was not found.                |
| 409         | Resource conflict.                     |
| 422         | Request could not be processed.        |

## Automation platform guarantees

* Event ingest and automation execution use at-least-once delivery semantics.
* Reuse `idempotency_key` on `POST /events` whenever your source system can retry.
* Wait timeouts are scheduler-based and should be treated as approximate, not millisecond exact.
* Event ordering is best effort and should not be treated as a strict serial log.
* Retention windows for events, runs, and waits are controlled at the project policy level.
* Plan limits and metered usage may apply to event ingest, automation runs, waits, template tests, and send actions.