Merge pull request #85300 from michaelryanmcneill/OSDOCS-12739

OSDOCS-12739: Explaining what external authentication is for

Author: bmcelvee

rosa_hcp/rosa-hcp-sts-creating-a-cluster-ext-auth.adoc

@@ -6,7 +6,7 @@ include::_attributes/attributes-openshift-dedicated.adoc[]
 
 toc::[]
 
-You can create {hcp-title-first} clusters that use external authentication to issue your access tokens.
+You can create {hcp-title-first} clusters that use an external OpenID Connect (OIDC) identity provider to issue tokens for authentication, replacing the built-in OpenShift OAuth server. While the built-in OpenShift OAuth server supports integration with a variety of identity providers, including external OIDC identity providers, it is limited to the capabilities of the OAuth server itself. You can directly integrate external OIDC identity providers with {hcp-title} clusters in order to facilitate machine-to-machine workflows, such as CLI, and provide additional capabilities which are not available when using the built-in OpenShift OAuth server.
 
 [IMPORTANT]
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