diff --git a/sdk/evaluation-result.json b/sdk/evaluation-result.json
index 5afd5c5aa12f..2d71eb3356e5 100644
--- a/sdk/evaluation-result.json
+++ b/sdk/evaluation-result.json
@@ -28,9 +28,12 @@
                     "type": "string"
                 },
                 "variant": {
-                    "description": "A stable identifier of the selected multivariate variant. Omitted when no variant was selected, or when the selected variant has no key set.",
+                    "description": "A stable identifier of the multivariate variant the identity was bucketed into: the variant's key, \"control\" for the control bucket, or null when no multivariate split applied (a standard feature, an unkeyed variant, or evaluation without an identity).",
                     "title": "Variant",
-                    "type": "string"
+                    "type": [
+                        "string",
+                        "null"
+                    ]
                 },
                 "metadata": {
                     "existingJavaType": "java.util.Map<String,Object>",
@@ -43,7 +46,8 @@
                 "name",
                 "enabled",
                 "value",
-                "reason"
+                "reason",
+                "variant"
             ],
             "title": "FlagResult",
             "type": "object"