Returns the attribute declarations of the schema component, if any. The context item is used if no argument is given.
xdmp.describe(xdmp.unquote( '<html xmlns="http://www.w3.org/1999/xhtml">\n\ <head><title>Example</title></head>\n\ <body><p><a id="a1">Example</a></p></body>\n\ </html>').next().value.root.xpath( "/sc:element-decl()!sc:attributes()")); => *["@version", "@xml:lang"]