Communication can be passed between components, such as an enterprise system and a client application, by utilizing schemas. A schema can ensure that a communication, such as a request or response, is in the proper format for one of the components. For instance, metadata can be received from an enterprise system in response to a request from a client application. That metadata can be transformed into an XML document that conforms to an XML schema. At least portions of the XML document can be validated against the XML schema. Those portions can be queried using a document interface component, such as an XML document API, that provides a path interface to elements in an XML document. The XML document can be passed on to the client application after validation.This description is not intended to be a complete and accurate description of the invention or to limit the scope of the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.