The Asset Score Preview API Test Harness is PHP code that will be made publicly accessible to software developers supporting the DOE commercial energy scoring efforts. Asset Score is a DOE funded web-based application that enables cities to interactively describe commercial buildings, identify assets that would affect the energy footprint of the building, and use the Asset Score models (FEDS, Open Studio) to determine the approximate energy score. In FY16 PNNL provided an application programmers interface (API) that enables third party software providers to directly access the 'Preview' feature of Asset Score. As part of the delivery of the API PNNL will also provide a 'Test Harness' that can be used externally to verify that the Preview APIs work. It also provides sample code for external developers to see how the API is applied.