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Benefits of Using Prelude with Auth0

  • Improved SMS Deliverability – Prelude offers high success rates for message delivery, reducing the risk of authentication failures.
  • Anti-Fraud Protection – Prelude’s advanced fraud detection system helps prevent abuse of your authentication system by identifying and blocking suspicious patterns.
  • Multi-Region Routing – Prelude automatically routes messages through the optimal carrier network based on the destination country, ensuring fast delivery worldwide.
  • Multi-Channel Support – Prelude supports SMS, WhatsApp, Viber and RCS channels for verification codes, giving your users more flexibility in how they receive authentication codes.
  • Seamless Integration – Works effortlessly with Auth0’s phone authentication, allowing you to set up in minutes.
This guide walks you through the integration process step-by-step, so you can enhance your Auth0 authentication system with Prelude’s powerful API.

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Prerequisites

  • An Auth0 project.
  • A Prelude account.

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Step 1: Configure Prelude for Auth0

  • Enable the Auth0 integration by going to Settings > Integrations > Auth0 in your Prelude’s Dashboard.
  • Create a new Secret Key for your Auth0 integration on Settings > API Keys and don’t forget to save or copy it.

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Step 2: Add the Action on Auth0

  1. Click Add Integration at the top of the page
  2. Review the required access permissions and click Continue
  3. Set up the integration:
    • Enter your Prelude Secret Key
  4. Click Create to save the integration in your Library
  5. In the pop-up window, select Add to flow
  6. Drag the Action element to your preferred spot in the flow
  7. Click Apply Changes to finalize

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Step 3: Activate custom SMS on Auth0

  1. Go to Dashboard > Security > Multi-factor Auth
  2. Click the Phone Message factor box
  3. In the modal that appears:
    • Select Custom for the delivery provider
    • Choose SMS as a delivery method
    • Message template is not supported yet
    • Click Save and close the modal
  4. Enable the SMS factor using the toggle switch
For more details on enabling and customizing MFA in Auth0, see:

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Correlation ID

A correlation ID is automatically generated within the Auth0 action integration using the format: 
auth0:${event.tenant.id}:${event.user.user_id}
This unique identifier helps with tracking authentication flows across systems.

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You’re All Set!

Congratulations! You’ve successfully integrated Prelude with your Auth0 project. Now when users authenticate using phone numbers in your Auth0 application, Prelude will handle the SMS verification process seamlessly.