How can I use Auth0 rules to add custom claims to tokens?

How can I use Auth0 rules to add custom claims to tokens?

You can use Auth0 rules to modify the ID token or access token by adding custom claims. This is done in the rules section of your Auth0 dashboard.

Can you give me an example of a rule that adds a custom claim?

Sure! Here's a simple example:

function (user, context, callback) {
  const namespace = 'https://myapp.example.com/';
  context.idToken[namespace + 'role'] = user.app_metadata.role;
  callback(null, user, context);
}

What is the purpose of using a namespace for custom claims?

Using a namespace helps to avoid collisions with standard claims and ensures that your custom claims are unique.

Are there any limitations on the size of custom claims?

Yes, there are limits on the size of tokens. Generally, the total size of the ID token should not exceed 8 KB.