diff --git a/models/story-category.go b/models/story-category.go
index d72d965..6af46ae 100644
--- a/models/story-category.go
+++ b/models/story-category.go
@@ -21,6 +21,16 @@ const (
 	StoryCategoryStory StoryCategory = "Story"
 )
 
+// IsValid returns whether the category is one of the valid values.
+func (e *StoryCategory) IsValid() bool {
+	switch *e {
+	case StoryCategoryInfo, StoryCategoryNews, StoryCategoryDocument, StoryCategoryBackground, StoryCategoryStory:
+		return true
+	default:
+		return false
+	}
+}
+
 // UnmarshalGQL unmarshals
 func (e *StoryCategory) UnmarshalGQL(v interface{}) error {
 	str, ok := v.(string)
@@ -28,13 +38,13 @@ func (e *StoryCategory) UnmarshalGQL(v interface{}) error {
 		return fmt.Errorf("enums must be strings")
 	}
 
-	*e = StoryCategory(str)
-	switch *e {
-	case StoryCategoryInfo, StoryCategoryNews, StoryCategoryDocument, StoryCategoryBackground, StoryCategoryStory:
-		return nil
-	default:
+	if !e.IsValid() {
 		return fmt.Errorf("%s is not a valid StoryCategory", str)
 	}
+
+	*e = StoryCategory(str)
+
+	return nil
 }
 
 // MarshalGQL turns it into a JSON string