Configuration URI Redirect in OpenID Connect Authentication

configured Front-channel and Back-channel URI but still getting
Required String parameter ‘redirect_uri’ is not present

Front channel and back channel are logout uris. This error message seems to be indicating something about log in. (The redirect uri is where the identity provider should send its response once it finishes the authentication.) Where are you seeing this message?

Message appears on Logout from Palantir

It appears that Cognito requires redirect_url, but Palantir doesn’t send

however configuration is provided

The “Redirect URL” listed in the configuration is the URL provided to the Identity Provider so that it knows where to send its responses (to the authorization, token, user info endpoints). And the logout urls provided in the configuration are used by the identity provider if you initiate a logout from there. There are two forms of logout: (1) from the identity provider and (2) from the application. In (1) the identity provider needs to know how to end a session in the application once the identity provider’s session has ended. When the logout starts in the application, there doesn’t need to be any update to the identity provider since that session can and should stay active.

Just to confirm - you’ve clicked logout in Palantir application and are seeing that message?