diff --git a/xep-0030.xml b/xep-0030.xml
index c44230b0..e0d7382b 100644
--- a/xep-0030.xml
+++ b/xep-0030.xml
@@ -862,9 +862,9 @@ xmpp:romeo@montague.net?disco;type=get;request=items
     <xs:complexType>
       <xs:simpleContent>
         <xs:extension base='empty'>
-          <xs:attribute name='category' type='xs:string' use='required'/>
+          <xs:attribute name='category' type='nonEmptyString' use='required'/>
           <xs:attribute name='name' type='xs:string' use='optional'/>
-          <xs:attribute name='type' type='xs:string' use='required'/>
+          <xs:attribute name='type' type='nonEmptyString' use='required'/>
         </xs:extension>
       </xs:simpleContent>
     </xs:complexType>
@@ -880,6 +880,12 @@ xmpp:romeo@montague.net?disco;type=get;request=items
     </xs:complexType>
   </xs:element>
 
+  <xs:simpleType name='nonEmptyString'>
+    <xs:restriction base='xs:string'>
+      <xs:minLength value='1'/>
+    </xs:restriction>
+  </xs:simpleType>
+
   <xs:simpleType name='empty'>
     <xs:restriction base='xs:string'>
       <xs:enumeration value=''/>
@@ -919,7 +925,7 @@ xmpp:romeo@montague.net?disco;type=get;request=items
     <xs:complexType>
       <xs:simpleContent>
         <xs:extension base='empty'>
-          <xs:attribute name='jid' type='xs:string' use='required'/>
+          <xs:attribute name='jid' type='fullJIDType' use='required'/>
           <xs:attribute name='name' type='xs:string' use='optional'/>
           <xs:attribute name='node' type='xs:string' use='optional'/>
         </xs:extension>
@@ -927,6 +933,13 @@ xmpp:romeo@montague.net?disco;type=get;request=items
     </xs:complexType>
   </xs:element>
 
+  <xs:simpleType name='fullJIDType'>
+    <xs:restriction base='xs:string'>
+      <xs:minLength value='8'/>
+      <xs:maxLength value='3071'/>
+    </xs:restriction>
+  </xs:simpleType>
+
   <xs:simpleType name='empty'>
     <xs:restriction base='xs:string'>
       <xs:enumeration value=''/>