diff --git a/packages/@aws-cdk/aws-appsync/lib/graphqlapi.ts b/packages/@aws-cdk/aws-appsync/lib/graphqlapi.ts
index 3644c3a04f49e..3df162f8bb5c4 100644
--- a/packages/@aws-cdk/aws-appsync/lib/graphqlapi.ts
+++ b/packages/@aws-cdk/aws-appsync/lib/graphqlapi.ts
@@ -69,25 +69,28 @@ function isApiKeyConfig(obj: unknown): obj is ApiKeyConfig {
     return (obj as ApiKeyConfig).apiKeyDesc !== undefined;
 }
 
-type AuthModes = UserPoolConfig | ApiKeyConfig;
-
 /**
  * Marker interface for the different authorization modes.
  */
+type AuthMode = UserPoolConfig | ApiKeyConfig;
+
+/**
+ * Configuration of the API authorization modes.
+ */
 export interface AuthorizationConfig {
     /**
      * Optional authorization configuration
      *
      * @default - API Key authorization
      */
-    readonly defaultAuthorization?: AuthModes;
+    readonly defaultAuthorization?: AuthMode;
 
     /**
      * Additional authorization modes
      *
      * @default - No other modes
      */
-    readonly additionalAuthorizationModes?: [AuthModes]
+    readonly additionalAuthorizationModes?: [AuthMode]
 }
 
 /**