Generic tests reach outside of the test framework provided by Team System, by running external applications and incorporating their results. They can be used to leverage existing testing frameworks and even your own independent test tools.
Using scripts, batch files, XML, XSL, and custom-written .NET console applications, one can vastly extend the capabilities of the test framework. Using a generic test is the quickest and easiest way to achieve test framework extensibility. This can be a big time saver and is quick and easy to implement.
An external application can return two types of results. One is an exit code, otherwise known as an ErrorLevel, for which 0 indicates a passed test and any other value is a failed test. The other option is for an external application to return an XML file that conforms to the generic test results schema and provides more test result types and reports on inner (sub) tests.