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

# Introduction

> The Senderz API provides programmatic access to Sender ID registration and A2P messaging across global markets.

## Two APIs, one integration

The Senderz platform exposes two resource namespaces under a single authentication and versioning model:

<CardGroup cols={2}>
  <Card title="Sender ID API" icon="shield-check" href="/sender-id-api/brands-overview">
    Register, manage, and monitor Sender ID registrations across supported markets. Onboard brands, submit SIDs, track approval status.
  </Card>

  <Card title="Messaging API" icon="message" href="/messaging-api/overview">
    Send and track 1-way A2P SMS messages via registered Sender IDs. OTP, logistics notifications, promotional alerts.
  </Card>
</CardGroup>

CPaaS providers, aggregators, and enterprise customers can use one or both namespaces depending on their integration needs.

## Base URL

All API requests use:

```
https://api.senderz.ai
```

## Quick start

<Steps>
  <Step title="Get your API key">
    Sign in to the [Senderz dashboard](https://senderz.ai) and generate an API key. Use `sz_test_` keys for sandbox testing, `sz_live_` keys for production.
  </Step>

  <Step title="Send your first message">
    ```bash theme={null}
    curl -X POST https://api.senderz.ai/v1/messaging/messages \
      -H "Authorization: Bearer sz_test_xxxxxxxxxxxxx" \
      -H "Content-Type: application/json" \
      -d '{
        "to": "+61400000000",
        "sender_id": "SecurBank",
        "body": "483291 is your verification code. It expires in 5 minutes. Do not share this code.",
        "market": "AU"
      }'
    ```
  </Step>

  <Step title="Check delivery status">
    ```bash theme={null}
    curl https://api.senderz.ai/v1/messaging/messages/msg_a1b2c3d4e5 \
      -H "Authorization: Bearer sz_test_xxxxxxxxxxxxx"
    ```
  </Step>
</Steps>

## Key concepts

| Concept       | Description                                                                                                                   |
| ------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| **Market**    | ISO 3166-1 alpha-2 country code (e.g. `AU`, `SG`, `HK`). Required on every resource. Determines routing and compliance rules. |
| **Brand**     | The legal entity that owns Sender IDs. Must be onboarded and verified before SID registration.                                |
| **Sender ID** | An alphanumeric identifier (2-11 chars) displayed as the message sender. Must be registered on the relevant market register.  |
| **Message**   | A single outbound SMS dispatched via a registered Sender ID.                                                                  |

## Versioning

The API version is embedded in the URL path: `/v1/`. Breaking changes increment the version. Non-breaking additions (new optional fields, new event types) do not.