diff --git a/specs/advanced-personalization/common/enums.yml b/specs/advanced-personalization/common/enums.yml
index b2d14b7064e..b5e87aaacfa 100644
--- a/specs/advanced-personalization/common/enums.yml
+++ b/specs/advanced-personalization/common/enums.yml
@@ -29,3 +29,8 @@ strategy:
     - historical
     - hybrid
   example: 'session'
+
+userType:
+  title: userType
+  type: string
+  enum: [basic, predictive, realtime]
diff --git a/specs/advanced-personalization/common/schemas/User.yml b/specs/advanced-personalization/common/schemas/User.yml
index a4d62fe7fda..227b325601e 100644
--- a/specs/advanced-personalization/common/schemas/User.yml
+++ b/specs/advanced-personalization/common/schemas/User.yml
@@ -3,6 +3,8 @@ user:
   properties:
     userID:
       type: string
+    type:
+      $ref: '../enums.yml#/userType'
     affinities:
       type: array
       items:
@@ -27,4 +29,4 @@ user:
         required: [name, indices, value, score, lastUpdatedAt]
     lastUpdatedAt:
       type: string
-  required: [userID, affinities, lastUpdatedAt]
+  required: [userID, type, affinities, lastUpdatedAt]