> ## Documentation Index
> Fetch the complete documentation index at: https://auth0.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Configure a Custom Phone Provider with Twilio Verify

> Use a custom-phone-provider Action to integrate Twilio Verify into Auth0 and route MFA and passwordless SMS codes through the Twilio Verify API.

<Steps>
  <Step title="Prerequisites">
    * You must have a [Twilio](https://twilio.com/) account with a valid SMS and/or phone delivery option.

    * You must create a [Twilio Verify](https://www.twilio.com/docs/verify) service through the [Twilio Console](https://www.twilio.com/console/verify/services) or the [Verify REST API](https://www.twilio.com/docs/verify/api/service#create-a-verification-service).
  </Step>

  <Step title="Set up a custom phone message provider">
    From [Dashboard > Branding > Phone Provider](https://manage.auth0.com/dashboard/#/phone/templates/phone/provider), under **Phone Provider**, choose **Custom**.

    Under **Provider Configuration**, add the following code sample to allow the Twilio API to send phone messages to a user's phone number:

    ```javascript lines expandable theme={null}
    /**
    * Handler to be executed while sending a phone notification
    * @param {Event} event - Details about the user and the context in which they are logging in.
    * @param {CustomPhoneProviderAPI} api - Methods and utilities to help change the behavior of sending a phone notification.
    */
    exports.onExecuteCustomPhoneProvider = async (event, api) => {
     const { TWILIO_ACCOUNT_SID, TWILIO_AUTH_TOKEN, TWILIO_VERIFY_SID } = event.secrets;

      const client = require('twilio')(TWILIO_ACCOUNT_SID, TWILIO_AUTH_TOKEN);

      // map auth0 voice value to call
      const messageType = event.notification.delivery_method === 'voice' ? 'call' : 'sms';

      const { recipient, code } = event.notification;

      // add this to fix " 1333444999  "
      // "333 444 5555"
      const sanitizedNumber = recipient.replace(/\s/g, '').trim();

      await client.verify.v2.services(TWILIO_VERIFY_SID)
        .verifications.create({
          to: sanitizedNumber,
          channel: messageType,
          customCode: code
        })

    };
    ```
  </Step>

  <Step title="Add secrets">
    Select the **Key** icon to open the **Secrets** menu. Add the following values from your Twilio Verify service setup:

    * `TWILIO_ACCOUNT_SID`
    * `TWILIO_AUTH_TOKEN`
    * `TWILIO_VERIFY_SID`
  </Step>

  <Step title="Load Twilio helper library">
    Select the **Dependency** icon, then choose **Add Dependency**. In the **Add Dependency** window that opens, enter the following values:

    * **Name**: `twilio`
    * **Version**: `latest`

    Select **Create** and Auth0 searches for the Twilio helper library and loads the latest version.
  </Step>

  <Step title="Deploy and test">
    Select **Save** to save and deploy the Action.

    To test the custom phone provider configuration before using it in a production environment, select **Send Test Message**.
  </Step>
</Steps>