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

# Write an SMS Autoresponder

> Build a keyword-based SMS autoresponder for automated replies

## Overview

This guide shows how to write an autoresponder for SMS text messages. Autoresponders can streamline marketing campaigns and subscription signups and reduce the amount of work humans have to do.

You can create an autoresponder either by using our PHLO visual workflow builder or our APIs. Follow the instructions in one of the tabs below.

<Tabs>
  <Tab title="Using API">
    To implement SMS Autoresponder use-case in the traditional API way, you can refer to the instructions in the below section to begin your implementation.

    <h2 id="api-{{'Outline' | slugify}}">Outline</h2>

    <Frame>
      <img src="https://mintcdn.com/plivo/sqGJ0ONkT5kTuesy/images/sms-autoresponder.png?fit=max&auto=format&n=sqGJ0ONkT5kTuesy&q=85&s=efe5ae0859d2a62184abc7a876bec19e" alt="Outbound-SMS Flow" width="1446" height="774" data-path="images/sms-autoresponder.png" />
    </Frame>

    <h2 id="api-{{'Implementation' | slugify}}">Implementation</h2>

    In this section, we will guide you in setting up an app using Plivo's API to implement SMS Autoresponder use-case. First, let’s make sure you meet these prerequisites before we dive into the code.

    <h3 id="api-{{'Prerequisites' | slugify}}">Prerequisites</h3>

    To get started, you need a Plivo account —  [sign up](https://cx.plivo.com/signup) with your work email address if you don’t have one already. To receive incoming messages, you must have a Plivo phone number that supports SMS; you can rent numbers from the [Numbers](https://cx.plivo.com/phone-numbers) page of the Plivo console or by using the [Numbers API](/docs/numbers/). If this is your first time using Plivo APIs, follow our instructions to set up a PHP development environment.

    <h2 id="api-{{'Create a Laravel controller to receive and respond to SMS messages' | slugify}}">Create a Laravel controller to receive and respond to SMS messages</h2>

    Change to the project directory and run this command.

    ```shell theme={null}
    $ php artisan make:controller SMSController
    ```

    This command generates a controller named SMSController in the app/http/controllers/ directory. Edit app/http/controllers/SMSController.php and paste into it this code.

    ```php theme={null}
    <?php

    namespace App\Http\Controllers;

    use Illuminate\Http\Request;
    use Plivo\XML\Response;

    class SMSController extends Controller
    {
        public function autoresponder()
        {
            $from_number = $_POST["From"];
            $to_number = $_POST["To"];
            $text = $_POST["Text"];

            if (strtolower($text) == "interested")
                $body = "Thank you for showing interest. One of our agents will contact you.";
            else
                $body = "Reply 'Interested' to connect with our agents";

            $response = new Response();
            $params = array(
                'src' => $to_number,
                'dst' => $from_number
            );
            $response->addMessage($body, $params);
            Header('Content-type: text/xml');
            return $response->toXML();
        }
    }
    ```

    Edit routes/web.php and add this line at the end of the file.

    ```shell theme={null}
    Route::match(['get', 'post'], '/autoresponder', 'SMSController@autoresponder');
    ```

    <Note>
      <strong>Note:</strong>
      If you’re using Laravel 8, use the fully qualified class name for your controllers — for example:

      ```
      Route::match(['get', 'post'], '/sendSMS', 'App\Http\Controllers\SMSController@sendSMS');
      ```

      For ngrok test, add this line to mylaravelapp/quickstart/app/Http/Middleware/VerifyCsrfToken.php.

      ```
      protected $except = ['*'];
      ```
    </Note>

    Run your code.

    ```shell theme={null}
    $ php artisan serve
    ```

    You should see your basic server application in action at  [http://localhost:8000/autoresponder](http://localhost:8000/autoresponder).

    Set up ngrok to expose your local server to the internet.

    <h2 id="api-create-a-plivo-application-for-autoresponder">Create a Plivo application for the autoresponder</h2>

    Associate the controller you created with Plivo by creating a Plivo application. Visiting Messaging > [Applications](https://cx.plivo.com/xml-applications) and click **Add New Application**. You can also use Plivo's [Application API](/docs/account/api/application/#create-an-application).

    Give your application a name — we called ours `Autoresponder`. Enter the server URL you want to use (for example `https://<yourdomain>.com/autoresponder/`) in the `Message URL` field and set the method to `POST`. Click **Create Application** to save your application.

    <Frame>
      <img src="https://mintcdn.com/plivo/EvRfP72Bjs4tuRt5/images/create-app-autoresponder.png?fit=max&auto=format&n=EvRfP72Bjs4tuRt5&q=85&s=7f9aa51d5cbdd884072e6a53b53df53e" alt="Create Application" width="2874" height="1574" data-path="images/create-app-autoresponder.png" />
    </Frame>

    <h2 id="api-assign-a-plivo-number-to-your-application">Assign a Plivo number to your application</h2>

    Navigate to the [Numbers](https://cx.plivo.com/phone-numbers) page and select the phone number you want to use for this application.

    From the Application Type drop-down, select `XML Application`.

    From the Plivo Application drop-down, select `Autoresponder` (the name we gave the application).

    Click **Update Number** to save.

    <Frame>
      <img src="https://mintcdn.com/plivo/EvRfP72Bjs4tuRt5/images/create-app-autoresponder.png?fit=max&auto=format&n=EvRfP72Bjs4tuRt5&q=85&s=7f9aa51d5cbdd884072e6a53b53df53e" alt="Create Application" width="2874" height="1574" data-path="images/create-app-autoresponder.png" />
    </Frame>

    <h2 id="Test">Test</h2>
    Send a text message to the Plivo number you specified using any phone.
  </Tab>
</Tabs>