Expose primaryPhone in SAML response

How can I expose the primaryPhone base attribute? When I try to map to “${user.primaryPhone}” I get a generic error.

I have been able to configure my SAML app to expose the email, firstName and lastName base attributes for the user logging in using “${user.firstName}”, etc,.

Looking at the Profile Editor for the Okta user, it appears there should be a “user.primaryPhone” variable available.
The App User for my SAML App has only a “userName” base attribute, but that does not seem to limit me from accessing the Okta user email attribute.

I expect some mapping needs to occur to expose this?

Apparently the answer is to use “user.primaryPhone” without the $ or {}.