You are here REST API - Libraries is a web API that converts legacy/proprietary files such as Text (CSV, tab delimited) and XLS (Excel) into XML in real-time so that it can be consumed by Internet, mobile, and desktop apps. The source file must be reachable via a URL, or must reside within a ZIP file that is reachable via a URL. was created out of the need to consume the data from government sites and convert it into a usable format.