[SCB-1673] add response description

Signed-off-by: kakulisen <18813972746@163.com>
diff --git a/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/annotation/ApiResponseMethodAnnotationProcessor.java b/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/annotation/ApiResponseMethodAnnotationProcessor.java
index ea2a748..702c2f1 100644
--- a/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/annotation/ApiResponseMethodAnnotationProcessor.java
+++ b/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/annotation/ApiResponseMethodAnnotationProcessor.java
@@ -46,6 +46,8 @@
 
     if (StringUtils.isNotEmpty(response.description())) {
       apiResponse.setDescription(response.description());
+    } else {
+      apiResponse.description("OK");
     }
 
     Header[] headersAnnotation = response.headers();
diff --git a/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/context/OperationContext.java b/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/context/OperationContext.java
index 7941e54..58d1b01 100644
--- a/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/context/OperationContext.java
+++ b/oas-generator/oas-generator-core/src/main/java/org/apache/servicecomb/toolkit/generator/context/OperationContext.java
@@ -212,6 +212,7 @@
       for (String produce : produceList) {
         content.addMediaType(produce, mediaType);
       }
+      apiResponse.description("OK");
       apiResponse.setContent(content);
       addResponse(HttpStatuses.OK, apiResponse);
     }