XML Editor XMLFox is a set of XML tools: XMLFox Advance XML/XSD editor and XML conversion module with command-line interface. XMLFox Advance is XML editing and validation tool for creating valid well-formed XML documents and/or XSD Schema. XMLFox schema editor enables you to easily develop advanced data models expressed in XSD Schema. It is the XML Schema Editor to provide a synchronized split-pane interface that simultaneously shows both a visual XML Schema Diagram and the underlying code, with changes in one pane immediately reflected in the other.