diff --git a/reference/spl/cachingiterator.xml b/reference/spl/cachingiterator.xml
index 0dc0805efc..be00f5dd99 100644
--- a/reference/spl/cachingiterator.xml
+++ b/reference/spl/cachingiterator.xml
@@ -111,35 +111,43 @@
     <varlistentry xml:id="cachingiterator.constants.call-tostring">
      <term><constant>CachingIterator::CALL_TOSTRING</constant></term>
      <listitem>
-      <para>Description here...</para>
+      <para>Convert every element to string.</para>
      </listitem>
     </varlistentry>
 
     <varlistentry xml:id="cachingiterator.constants.catch-get-child">
      <term><constant>CachingIterator::CATCH_GET_CHILD</constant></term>
      <listitem>
-      <para>Description here...</para>
+      <para>Don't throw exception in accessing children.</para>
      </listitem>
     </varlistentry>
 
     <varlistentry xml:id="cachingiterator.constants.tostring-use-key">
      <term><constant>CachingIterator::TOSTRING_USE_KEY</constant></term>
      <listitem>
-      <para>Description here...</para>
+      <para>
+       Use <link linkend="cachingiterator.key">key</link> for conversion to
+       string.
+      </para>
      </listitem>
     </varlistentry>
 
     <varlistentry xml:id="cachingiterator.constants.tostring-use-current">
      <term><constant>CachingIterator::TOSTRING_USE_CURRENT</constant></term>
      <listitem>
-      <para>Description here...</para>
+      <para>
+       Use <link linkend="cachingiterator.current">current</link> for
+       conversion to string.</para>
      </listitem>
     </varlistentry>
 
     <varlistentry xml:id="cachingiterator.constants.tostring-use-inner">
      <term><constant>CachingIterator::TOSTRING_USE_INNER</constant></term>
      <listitem>
-      <para>Description here...</para>
+      <para>
+       Use <link linkend="cachingiterator.getinneriterator">inner</link>
+       for conversion to string.
+      </para>
      </listitem>
     </varlistentry>