This page will list tools to test conformance of WIS Discovery Metadata records.
Testing using XML Schema
The XML Schema definition available at MDG_Schema is exactly same as that of ISO 19139. If you have validator for ISO 19139, that also works for your WIS Discovery Metadata.
Testing using Schematron
Additional set of rule-based tests is given in the Schematron language is available MDG_Schema. The word "additional" means the tests supplements (not overlaps or substitutes) the XML Schema.
NOAA/NGDC's WMO Validation Service
accepts a metadata record by URL or XML file upload, and then displays the evaluation result.
Linux and many UNIX systems comes with GNOME libxml2 and libxslt. That provides console method to validate compliance.
$ xmllint /.../gmx/gmx.xsd yourRecord.xml
$ xsltproc wcmp13.xsl yourRecord.xml
Testing using Python
Tom Kralidis from the Meteorological Service of Canada has developed a
Python test suite for validating WMO Core Profile 1.3 metadata. The
test suite is available in from the OGC Meteorology Ocean Domain
Working Group GitHub software repository at
https://github.com/OGCMetOceanDWG/wmo-cmp-ts with a MIT license.