xmltool validate|indent|schematron|schemadoc ?
The xmltool utility comprises 4 different processors:
May also be used to check the validity of a DTD, W3C XML Schema or RELAX NG schema.
Saves one or more documents after reformatting their XML contents.
Checks the validity of a document against a Schematron schema.
May also be used to check the validity of a Schematron schema.
Generates a reference manual in HTML format for a DTD, W3C XML Schema or RELAX NG schema.
The generated HTML reference manual, organized like "DocBook: The Definitive Guide" by Norman Walsh and al., lists all the elements and attributes specified in the schema.
This manual is intended to help content authors create instances conforming to a given schema. This manual is not intended to help schema authors document their design.
Note that, for now, this documentation generator cannot extract documentation contained in a schema (i.e. in annotation/documentation elements) and merge extracted documentation with automatically generated documentation.