diff -rN -u old-smederee/modules/html-utils/src/main/scala/de/smederee/html/MetaTags.scala new-smederee/modules/html-utils/src/main/scala/de/smederee/html/MetaTags.scala
--- old-smederee/modules/html-utils/src/main/scala/de/smederee/html/MetaTags.scala	2025-01-16 09:50:46.424902093 +0000
+++ new-smederee/modules/html-utils/src/main/scala/de/smederee/html/MetaTags.scala	2025-01-16 09:50:46.424902093 +0000
@@ -18,10 +18,46 @@
 package de.smederee.html
 
 enum MetaRobotsDirective(val tag: String) {
-  case Follow   extends MetaRobotsDirective("follow")
-  case Index    extends MetaRobotsDirective("index")
+
+  /** Equivalent to index, follow. Used by Google
+    */
+  case All extends MetaRobotsDirective("all")
+
+  /** Allows the robot to follow the links on the page (default). Used by all.
+    */
+  case Follow extends MetaRobotsDirective("follow")
+
+  /** Allows the robot to index the page (default). Used by all.
+    */
+  case Index extends MetaRobotsDirective("index")
+
+  /** Requests the search engine not to cache the page content. Used by Bing, Google, Yahoo.
+    */
+  case NoArchive extends MetaRobotsDirective("noarchive")
+
+  /** Synonym of noarchive. Used by Bing.
+    */
+  case NoCache extends MetaRobotsDirective("nocache")
+
+  /** Requests the robot to not follow the links on the page. Used by all.
+    */
   case NoFollow extends MetaRobotsDirective("nofollow")
-  case NoIndex  extends MetaRobotsDirective("noindex")
+
+  /** Requests this page not to appear as the referring page of an indexed image. Used by Google.
+    */
+  case NoImageIndex extends MetaRobotsDirective("noimageindex")
+
+  /** Requests the robot to not index the page. Used by all.
+    */
+  case NoIndex extends MetaRobotsDirective("noindex")
+
+  /** Prevents displaying any description of the page in search engine results. Used by Bing, Google.
+    */
+  case NoSnippet extends MetaRobotsDirective("nosnippet")
+
+  /** Equivalent to noindex, nofollow. Used by Google.
+    */
+  case None extends MetaRobotsDirective("none")
 }
 
 opaque type MetaDescription = String
@@ -93,15 +129,33 @@
   *   An optional description for the related meta tag which should not be too long (max. 160/200 characters).
   * @param keywords
   *   A list of keywords which can be empty and should not be too long.
+  * @param robots
+  *   A set of directives for the meta tag "robots" to affect search engine / crawler indexing behaviour.
   */
-final case class MetaTags(description: Option[MetaDescription], keywords: MetaKeyWords)
+final case class MetaTags(
+    description: Option[MetaDescription],
+    keywords: MetaKeyWords,
+    robots: Set[MetaRobotsDirective]
+)
 
 object MetaTags {
 
+  /** Return a default instance of meta tags which is empty and has the nofollow and noindex flags for robots set.
+    *
+    * @return
+    *   An instance of meta tags containing only nofollow and noindex flags for robots.
+    */
+  def default: MetaTags =
+    MetaTags(
+      description = None,
+      keywords = MetaKeyWords.empty,
+      robots = Set(MetaRobotsDirective.NoFollow, MetaRobotsDirective.NoIndex)
+    )
+
   /** Return an empty meta tags instance.
     *
     * @return
     *   An instance of meta tags containing no values, resulting in no tags being rendered.
     */
-  def empty: MetaTags = MetaTags(description = None, keywords = MetaKeyWords.empty)
+  def empty: MetaTags = MetaTags(description = None, keywords = MetaKeyWords.empty, robots = Set.empty)
 }