diff --git a/docs/openapi/genarrative-external-v1.openapi.json b/docs/openapi/genarrative-external-v1.openapi.json
index fd8dee488..67596e4dd 100644
--- a/docs/openapi/genarrative-external-v1.openapi.json
+++ b/docs/openapi/genarrative-external-v1.openapi.json
@@ -2508,6 +2508,13 @@
             "type": "string",
             "minLength": 1
           },
+          "screenColor": {
+            "type": [
+              "string",
+              "null"
+            ],
+            "description": "纯色抠像背景色。可传画布支持的纯色背景 hex（如 #CFEFFF）指定；传 \"auto\"、null 或省略则由服务端自动决策。"
+          },
           "size": {
             "type": "string",
             "description": "兼容旧 size 入参；未传 aspectRatio/imageSize 时生效。",
@@ -2872,6 +2879,13 @@
               "type": "string"
             }
           },
+          "screenColor": {
+            "type": [
+              "string",
+              "null"
+            ],
+            "description": "纯色抠像背景色。可传画布支持的纯色背景 hex（如 #CFEFFF）指定；传 \"auto\"、null 或省略则由服务端自动决策。"
+          },
           "model": {
             "type": "string",
             "default": "gemini-3.1-flash-image-preview"
@@ -2937,6 +2951,13 @@
             "type": "string",
             "description": "UI 设计图 Data URL 或 objectKey。"
           },
+          "screenColor": {
+            "type": [
+              "string",
+              "null"
+            ],
+            "description": "纯色抠像背景色。可传画布支持的纯色背景 hex（如 #CFEFFF）指定；传 \"auto\"、null 或省略则由服务端自动决策。"
+          },
           "model": {
             "type": "string",
             "default": "gemini-3.1-flash-image-preview",
@@ -3163,6 +3184,13 @@
             "minLength": 1,
             "maxLength": 4000
           },
+          "screenColor": {
+            "type": [
+              "string",
+              "null"
+            ],
+            "description": "纯色抠像背景色。可传画布支持的纯色背景 hex（如 #CFEFFF）指定；传 \"auto\"、null 或省略则由服务端自动决策。"
+          },
           "resolution": {
             "type": "string",
             "enum": [