> ## 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.

# Overview

> Send and track 1-way A2P SMS messages via registered Sender IDs.

## Messaging API

The Messaging API lets you send outbound SMS messages to recipients worldwide using registered alphanumeric Sender IDs. Messages are 1-way (mobile-terminated only).

Common use cases:

* **OTP / 2FA codes** (e.g. `"829104 is your verification code. Expires in 5 minutes."`)
* **Logistics notifications** (e.g. `"Your order SYD-90421 has been dispatched. Expected delivery: tomorrow by 5pm."`)
* **Promotional alerts** (e.g. `"Flash sale: 30% off all winter styles. Ends midnight. Shop now at example.com/sale"`)

## Message lifecycle

```
queued → sent → delivered
                └→ undelivered
       └→ failed
```

| Status        | Description                                                        |
| ------------- | ------------------------------------------------------------------ |
| `queued`      | Accepted, pending dispatch                                         |
| `sent`        | Dispatched to carrier                                              |
| `delivered`   | Delivery confirmed by carrier                                      |
| `undelivered` | Carrier confirmed non-delivery                                     |
| `failed`      | Rejected before dispatch (validation, compliance, or system error) |
| `scheduled`   | Queued for future delivery                                         |
| `cancelled`   | Scheduled message cancelled before dispatch                        |

## Encoding

Message content is auto-encoded as GSM-7 (standard ASCII, 160 chars per segment) or UCS-2 (Unicode, 70 chars per segment). Long messages are auto-concatenated into multiple segments.

## Pricing

Each message reports its cost in the response:

```json theme={null}
"price": {
  "amount": "0.055",
  "currency": "AUD"
}
```

Pricing varies by destination market. Multi-segment messages are charged per segment.