Systems and methods for providing an API for a database system. The API may be provided to enable external application developers to build applications that can support the dynamic security model of the content management system and describe the runtime properties of records in data objects. The API of may provide a record property object and/or a query describe object when returning data set in response to a query by providing information about actions an end user can take on the data records, and to provide metadata required to understand a data response.