diff --git a/clients/client-appsync/src/commands/UpdateGraphqlApiCommand.ts b/clients/client-appsync/src/commands/UpdateGraphqlApiCommand.ts
index bb6465d2320d..2e7b46189237 100644
--- a/clients/client-appsync/src/commands/UpdateGraphqlApiCommand.ts
+++ b/clients/client-appsync/src/commands/UpdateGraphqlApiCommand.ts
@@ -42,7 +42,7 @@ export interface UpdateGraphqlApiCommandOutput extends UpdateGraphqlApiResponse,
  *     cloudWatchLogsRoleArn: "STRING_VALUE", // required
  *     excludeVerboseContent: true || false,
  *   },
- *   authenticationType: "API_KEY" || "AWS_IAM" || "AMAZON_COGNITO_USER_POOLS" || "OPENID_CONNECT" || "AWS_LAMBDA",
+ *   authenticationType: "API_KEY" || "AWS_IAM" || "AMAZON_COGNITO_USER_POOLS" || "OPENID_CONNECT" || "AWS_LAMBDA", // required
  *   userPoolConfig: { // UserPoolConfig
  *     userPoolId: "STRING_VALUE", // required
  *     awsRegion: "STRING_VALUE", // required
diff --git a/clients/client-appsync/src/models/models_0.ts b/clients/client-appsync/src/models/models_0.ts
index 38aa1f18b071..860ab0403fb7 100644
--- a/clients/client-appsync/src/models/models_0.ts
+++ b/clients/client-appsync/src/models/models_0.ts
@@ -5321,7 +5321,7 @@ export interface UpdateGraphqlApiRequest {
    * <p>The new authentication type for the <code>GraphqlApi</code> object.</p>
    * @public
    */
-  authenticationType?: AuthenticationType;
+  authenticationType: AuthenticationType | undefined;
 
   /**
    * <p>The new Amazon Cognito user pool configuration for the <code>~GraphqlApi</code> object.</p>
diff --git a/codegen/sdk-codegen/aws-models/appsync.json b/codegen/sdk-codegen/aws-models/appsync.json
index 9b9753958801..373aca4b0a2f 100644
--- a/codegen/sdk-codegen/aws-models/appsync.json
+++ b/codegen/sdk-codegen/aws-models/appsync.json
@@ -7332,7 +7332,7 @@
           "min": 20,
           "max": 2048
         },
-        "smithy.api#pattern": "^arn:[a-z-]*:secretsmanager:[a-z0-9-]*:\\d{12}:secret:[0-9A-Za-z_/-]*$"
+        "smithy.api#pattern": "^arn:[a-z-]*:secretsmanager:[a-z0-9-]*:\\d{12}:secret:[0-9A-Za-z_/+=.@!-]*$"
       }
     },
     "com.amazonaws.appsync#RdsHttpEndpointConfig": {
@@ -8936,7 +8936,8 @@
         "authenticationType": {
           "target": "com.amazonaws.appsync#AuthenticationType",
           "traits": {
-            "smithy.api#documentation": "<p>The new authentication type for the <code>GraphqlApi</code> object.</p>"
+            "smithy.api#documentation": "<p>The new authentication type for the <code>GraphqlApi</code> object.</p>",
+            "smithy.api#required": {}
           }
         },
         "userPoolConfig": {