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

# AI SMS Support

> Route inbound SMS conversations from OpenCX into the Zendesk Agent Workspace as live Sunshine chats.

SMS conversations route through <Tooltip tip="Zendesk's real-time messaging layer. Conversations surface in the Agent Workspace as live chats rather than tickets.">Sunshine Conversations</Tooltip>. When the AI hands off an SMS thread, your rep picks it up as a live chat inside the Zendesk <Tooltip tip="Zendesk's unified UI where agents handle tickets and live messaging side by side.">Agent Workspace</Tooltip> and replies on the same number the customer texted.

## Pre-requisites

<Warning>
  **Connect and verify your SMS number first.** No inbound SMS can reach OpenCX until the channel is live — start with [Connect SMS](/sms/connect-sms) and come back here.
</Warning>

* **SMS number connected and verified** — see [Connect SMS](/sms/connect-sms) and, for US numbers, [SMS compliance](/sms/compliance).
* **Zendesk Sunshine credentials saved** — see [Sunshine Conversations](/integrations/zendesk/sunshine-conversations).

## How conversations land in Zendesk

```mermaid theme={"dark"}
flowchart LR
  A[Customer texts your SMS number] --> B[AI replies via SMS]
  B --> C{AI can resolve?}
  C -- Yes --> D[Conversation closes]
  C -- No --> E[Handoff via Sunshine]
  E --> F[Live chat in Agent Workspace]
  F --> G[Rep replies — lands as SMS]
```

## Setting up

<Steps>
  <Step title="Confirm SMS is connected">
    Open [**Channels → SMS**](https://platform.open.cx/channels/sms) in the OpenCX dashboard. Your SMS number should be listed and active.
  </Step>

  <Step title="Confirm Sunshine is connected">
    In [**Settings → Integrations**](https://platform.open.cx/settings/integrations), open **Zendesk → Messaging**. The status should show **Active**.
  </Step>

  <Step title="Trigger a test handoff">
    Text your connected number and ask to speak to a human. The AI should hand off.
  </Step>

  <Step title="Verify in the Zendesk Agent Workspace">
    The conversation should appear as a **live chat** tagged `opencx_channel_sms`. Reply from the Agent Workspace and confirm the response lands as an SMS on the customer's phone.
  </Step>
</Steps>

## What the rep sees

* A **live chat in the Agent Workspace** tagged `opencx_channel_sms`.
* Contact phone number attached via the Sunshine user.
* Full transcript of the AI-to-customer exchange.
* `opencx_session_id` on the conversation <Tooltip tip="Key-value pairs OpenCX attaches to every Sunshine conversation. Reachable via the Conversations API for debugging and analytics.">`metadata`</Tooltip> — the trace key to the full OpenCX session.
* Replies deliver as SMS within a couple of seconds, carrier willing.

## Channel-specific details

<AccordionGroup>
  <Accordion title="US number compliance" icon="flag">
    US SMS numbers require <Tooltip tip="10-Digit Long Code — a US carrier requirement for business messaging. Registering your number and campaigns reduces carrier filtering.">10DLC registration</Tooltip> or <Tooltip tip="A carrier-required verification process for US toll-free numbers used for business messaging.">toll-free verification</Tooltip> before they can reliably deliver outbound messages. Complete this on the OpenCX side — see [SMS compliance](/sms/compliance). The Zendesk integration doesn't change the requirement.
  </Accordion>

  <Accordion title="User merge by phone number" icon="phone">
    OpenCX matches Sunshine messaging contacts to existing Zendesk support users. SMS merges primarily on phone number; email is used only when the customer has shared one on another channel first.
  </Accordion>

  <Accordion title="Message length and segmentation" icon="ruler">
    SMS messages are split into 160-character segments by carriers. Reps in the Agent Workspace don't see the split — the full reply is sent as one logical message and the customer sees it as one thread. Keep replies tight; carrier costs scale per segment.
  </Accordion>

  <Accordion title="MMS" icon="image">
    Media sent by the customer (MMS) appears as attachments on the Sunshine conversation when the carrier supports it. Outbound MMS support depends on your SMS provider's capabilities.
  </Accordion>
</AccordionGroup>

***

## Related Documentation

<CardGroup cols={2}>
  <Card title="AI SMS Support" icon="comment-sms" href="/sms/introduction">
    The channel itself — connect, routing, compliance.
  </Card>

  <Card title="Sunshine Conversations setup" icon="plug" href="/integrations/zendesk/sunshine-conversations">
    Credentials, webhook, and user merge.
  </Card>

  <Card title="Zendesk overview" icon="headset" href="/integrations/zendesk/overview">
    What else Zendesk lights up across every channel.
  </Card>

  <Card title="Troubleshooting" icon="wrench" href="/integrations/zendesk/troubleshooting">
    Replies not reaching SMS, duplicate contacts.
  </Card>
</CardGroup>