Visual Studio 2013 and before had a seperate installer for Team Explorer. This allowed non-developers to access Team Foundation Server and all it’s functionality without the need to install a Visual Studio version. In VS 2015, Microsoft did not release a standalone Team Explorer but pointed customers to the free Express SKUs and Community editions, which included Team Explorer functionality.
This week with the Visual Studio 2017 Update release, the standalone Team Explorer installer is back. This is a free download for non-developers who connect to Team Foundation Server or Visual Studio Team Services.
Remark: Note that you probably still need a CAL(client access license).