diff --git a/docs/language-server/protocol-language-server.md b/docs/language-server/protocol-language-server.md
index 173709c7d9..e98648d069 100644
--- a/docs/language-server/protocol-language-server.md
+++ b/docs/language-server/protocol-language-server.md
@@ -428,16 +428,18 @@ The argument of a [`SuggestionEntry`](#suggestionentry).
 ```typescript
 // The argument of a constructor, method or function suggestion.
 interface SuggestionEntryArgument {
-  // The argument name
+  /** The argument name. */
   name: string;
-  // The argument type. String 'Any' is used to specify generic types
+  /** The argument type. String 'Any' is used to specify generic types. */
   type: string;
-  // Indicates whether the argument is lazy
+  /** Indicates whether the argument is lazy. */
   isSuspended: bool;
-  // Indicates whether the argument has default value
+  /** Indicates whether the argument has default value. */
   hasDefault: bool;
-  // Optional default value
+  /** Optional default value. */
   defaultValue?: string;
+  /** Optional list of possible values that this argument takes. */
+  tagValues?: string[];
 }
 ```
 
diff --git a/engine/polyglot-api/src/main/scala/org/enso/polyglot/Suggestion.scala b/engine/polyglot-api/src/main/scala/org/enso/polyglot/Suggestion.scala
index 13b74173f5..f80e57f8a1 100644
--- a/engine/polyglot-api/src/main/scala/org/enso/polyglot/Suggestion.scala
+++ b/engine/polyglot-api/src/main/scala/org/enso/polyglot/Suggestion.scala
@@ -142,6 +142,7 @@ object Suggestion {
     * @param isSuspended is the argument lazy
     * @param hasDefault does the argument have a default
     * @param defaultValue optional default value
+    * @param tagValues optional list of possible values
     */
   case class Argument(
     name: String,
@@ -160,6 +161,8 @@ object Suggestion {
       s"isSuspended=$isSuspended," +
       s"hasDefault=$hasDefault,defaultValue=" +
       (if (shouldMask) defaultValue.map(_ => STUB) else defaultValue) +
+      s",tagValues=" +
+      (if (shouldMask) tagValues.map(_ => STUB) else tagValues) +
       ")"
   }