In Microsoft Dynamics AX 2012 R3 CU8 we are now supporting VS 2013.
Please note for development we only support VS 2013 in R3 CU8.
For TFS we do support TFS 2010, TFS 2012, TFS 2013 and TFS online, but to connect to these from AX you will need “TFS 2010 object model Sp1” which is client to connect to server.
From system requirement document (http://www.microsoft.com/en-us/download/details.aspx?id=11094)
Client computers that are running Visual Studio 2010 must have hotfix KB 2662296 (http://support.microsoft.com/kb/2662296) installed to use TFS source control with Microsoft Dynamics AX.
Client computers that are not running Visual Studio 2010 must have the Team Foundation Server 2010 SP1 Object Model (https://visualstudiogallery.msdn.microsoft.com/a37e19fb-3052-4fc9-bef7-4a4682069a75) installed to use TFS source control with Microsoft Dynamics AX.