From eaa98cc35ff82bc3f935407546a4d5d42c29206e Mon Sep 17 00:00:00 2001
From: Gagan Trivedi <gagandeeptrivedi47@gmail.com>
Date: Mon, 8 Jun 2026 15:45:16 +0530
Subject: [PATCH] feat(sdk): make evaluation result variant required and
 nullable

Follow-up to #7704. The flag engine and SDKs always populate `variant`
(the variant's key, "control" for the control bucket, or null when no
multivariate split applied), mirroring OpenFeature's always-present,
nullable ResolutionDetails.variant. Make the schema match: `variant`
becomes required with type [string, null].
---
 sdk/evaluation-result.json | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

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"