Initial Update: Friday, 8 July 2016 00:47 UTC
We are actively investigating issues with Visual Studio Team Services where customers might receive internal server errors while trying to access their build definitions using Personal Access Tokens for their custom tools. We are in the process of understanding the root cause and deploying a fix on the impacted regions.
We are working to resolve this issue and apologize for any inconvenience.
Sincerely,
Manjunath