You can use Auth0’s to check whether an application is registered with Auth0 as a first-party or third-party application. Make a GET call to the Get a Client endpoint. Be sure to replace {yourClientId} and {yourMgmtApiAccessToken} placeholder values with your and Management API , respectively. 
curl --request GET \
--url 'https://{yourDomain}/api/v2/clients/%7ByourClientId%7D?fields=is_first_party&include_fields=true' \
--header 'authorization: Bearer {yourMgmtApiAccessToken}'
ValueDescription
YOUR_CLIENT_IDΤhe ID of the application to be updated.
MGMT_API_ACCESS_TOKENAccess Tokens for the Management API with the read:clients.
If the application is first-party, the is_first_party field will have a value of true. If the application is third-party, the is_first_party field will have a value of false.

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