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

# Retell AI

> Connect Poku's tools to your Retell AI voice agent.

Poku Labs is a proud [Retell AI App Partner](https://www.retellai.com/app-partner/poku-labs). You can add Poku's API as a custom function in any Retell agent — giving your voice AI the ability to text customers, capture structured data, loop in a manager, and more.

***

## Use cases

<CardGroup cols={2}>
  <Card title="Email capture over SMS" icon="envelope">
    Agent sends a text mid-call. Customer replies with their email. Agent reads it back and continues.
  </Card>

  <Card title="Form capture via WhatsApp" icon="wpforms">
    Agent sends a form link over WhatsApp. Customer fills it out on their phone while still on the call.
  </Card>

  <Card title="Loop in a manager" icon="phone-arrow-right">
    Agent texts a manager to check transfer availability before handing off — no dead air for the customer.
  </Card>

  <Card title="Quote approval via Slack" icon="slack">
    Agent pings a Slack channel for sign-off on a custom price, then relays the answer to the customer.
  </Card>
</CardGroup>

***

## See it in action

<iframe width="100%" style={{ aspectRatio: "16/9" }} src="https://www.youtube.com/embed/uoC3ehUe1C4" title="Poku + Retell AI" frameBorder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowFullScreen />

***

## Setup on Retell AI

<Steps>
  <Step title="Add a custom function">
    In your Retell agent, navigate to **Functions** and add a new custom function.

    <Frame>
      <img src="https://mintcdn.com/pokulabs-b271f9f5/np4TQgYBhDVOFtgW/images/Retell-1.png?fit=max&auto=format&n=np4TQgYBhDVOFtgW&q=85&s=90fc5e10c275a9f81190959eacb2e74f" alt="Adding a custom function in Retell AI" width="358" height="614" data-path="images/Retell-1.png" />
    </Frame>
  </Step>

  <Step title="Name and describe the function">
    The name and description can be anything — write them so your agent understands when to use the tool. For example: `send_sms`, *"Send an SMS to the customer and wait for their reply."*
  </Step>

  <Step title="Set the API endpoint">
    Select **POST** and enter the Poku API URL for the action you want:

    | Action             | URL                                          |
    | ------------------ | -------------------------------------------- |
    | Send SMS           | `https://api.pokulabs.com/messages/sms`      |
    | Send WhatsApp      | `https://api.pokulabs.com/messages/whatsapp` |
    | Send Slack message | `https://api.pokulabs.com/messages/slack`    |
  </Step>

  <Step title="Set the timeout">
    Set the function timeout to be **equal to or longer than the `waitTime` you plan to pass to Poku**.
  </Step>

  <Step title="Add the authorization header">
    Under **Headers**, add:

    | Key             | Value                        |
    | --------------- | ---------------------------- |
    | `Authorization` | `Bearer <your-poku-api-key>` |
  </Step>

  <Step title="Define the parameters">
    Under **Form**, add the parameters your agent will pass in the request body — for example `to`, `message`, and `waitTime`. These map directly to the [Poku API fields](/api-reference/messages/send-sms).

    <Frame>
      <img src="https://mintcdn.com/pokulabs-b271f9f5/np4TQgYBhDVOFtgW/images/Retell-2.png?fit=max&auto=format&n=np4TQgYBhDVOFtgW&q=85&s=243fef3a5466eb87100541c84d3aaca0" alt="Configuring parameters in Retell AI" width="737" height="1194" data-path="images/Retell-2.png" />
    </Frame>
  </Step>

  <Step title="Configure execution feedback">
    Under **During Execution**:

    * **Talk After Action Completed** — always enable this so your agent speaks after receiving the tool response
    * **Talk While Waiting** — enable this if you want the agent to keep talking with the customer while waiting for the Poku response (e.g., to fill dead air)
  </Step>

  <Step title="Update your agent prompt">
    Update your agent's system prompt to reference the new tool by name so it knows when and how to call it.
  </Step>
</Steps>

***

## Tips

**Prevent the agent from moving on before the tool call resolves**

If you don't want the agent to continue the conversation before receiving the Poku response, use a **multi-conversation flow** rather than a single prompt. This ensures the agent waits for the tool result before proceeding.