Per documentation on GitKraken's website I should be able to clone a git repo hosted in TFS 2015
What is not clear is should the repo be configured for HTTPS. When I try to clone my repo which has a http URL, in GitKraken I get a 401 error but GitKraken does not ask for credentials.
A repo that's hosted in GitLab behaves as expected by asking for credentials.
Is it possible to clone a http url to a git repo hosted in TFS 2015? Do I need to perform any tricks or configure anything on TFS?
TFS 2015 doesn't support the creation of Personal Access Tokens and GitKraken doesn't support Windows Authentication. So unless TFS 2015 is configured with SSL and basic-auth, then GitKraken can work and then it should prompt for creds.
If the server would be upgraded to TFS 2017 or 2018, you could use Personal Access Tokens without having to abandon Windows Authentication. Windows Auth is more secure than Basic Auth.