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

# Introduction to SMS agents

> What Lumina is and what an SMS agent can do

An SMS agent holds text-message conversations: it replies, runs actions, remembers the contact
between conversations, and closes the session when it's done.

<Warning>
  **Lumina handles inbound conversations.** For now it **cannot start** one: you can save an
  outbound Lumina agent, but it won't text first.

  If your use case is sending the first message — campaigns, scheduled reminders — that
  capability isn't available yet.
</Warning>

<Info>
  **📷 Screenshot needed** — the full SMS agent editor, with its three columns.

  Save to `/images/en/sms-agents/editor-overview.png`
</Info>

## What Lumina is

**Lumina is Dialtu's SMS engine.** Unlike other channels, Dialtu controls the whole
conversation end to end here: the prompt, the model turn, the tools and the history. The
carrier only transports the message.

In practice that means two things for you:

<CardGroup cols={2}>
  <Card title="Contact memory" icon="brain">
    A Lumina agent **does receive** the contact's memory, just like WhatsApp.
  </Card>

  <Card title="Opt-out keywords" icon="hand">
    Lumina recognises **STOP**, **HELP** and **START** automatically, before the model ever sees
    the message.
  </Card>
</CardGroup>

## The editor at a glance

A single screen with three columns, same as the other channels.

| Column              | What's in it                                                |
| ------------------- | ----------------------------------------------------------- |
| **Settings** (left) | Five groups: model, channel, behaviour, memory and outcomes |
| **Prompt** (centre) | A single document holding the instructions                  |
| **Right panel**     | Atlas, testing and summary                                  |

## What SMS does NOT have

Worth saying early, because these are real differences from WhatsApp:

| Not available                              | Detail                                                                            |
| ------------------------------------------ | --------------------------------------------------------------------------------- |
| **Tag audiences**                          | You can't restrict an agent to certain customers. Routing is **by schedule only** |
| **Reminders and follow-up sequences**      | They don't exist for SMS                                                          |
| **Conversation style and response length** | No controls; it's all defined in the prompt                                       |
| **Message batching**                       | Not configurable                                                                  |
| **Templates**                              | There are no approved templates as in WhatsApp                                    |

## What's in this section

<CardGroup cols={2}>
  <Card title="Create an SMS agent" icon="plus" href="/en/sms-agents/create-agent">
    The minimum fields to get it replying.
  </Card>

  <Card title="Configuration" icon="sliders" href="/en/sms-agents/configuration">
    Channel, schedule, behaviour, memory and outcomes.
  </Card>

  <Card title="Compliance and opt-outs" icon="shield-check" href="/en/sms-agents/compliance">
    STOP, HELP, START and A2P 10DLC registration.
  </Card>

  <Card title="Phone numbers" icon="phone" href="/en/getting-started/phone-numbers">
    How to get the number the agent needs.
  </Card>
</CardGroup>