How do I force a specific MFA factor?

[tatebosler]

I have a bunch of users that are currently using SMS for MFA, but I want to begin migrating them over to an OTP app. I would like to control the migration and only enable OTP for some internal users at first before making it available to everyone.

I know it’s possible to force a specific MFA provider using rules, but can rules (or some other configuration in the Auth0 dashboard) be used to force a specific MFA factor within Guardian?

[mathiasconradt]

In the rule, you can set a MFA factor via provider option, or any if you want to allow any provider:

    context.multifactor = {
      provider: 'any'
    };