diff --git a/templates/api-single.mustache b/templates/api-single.mustache
index 8d741db8..8d535189 100644
--- a/templates/api-single.mustache
+++ b/templates/api-single.mustache
@@ -5,6 +5,11 @@ require_relative '{{serviceName}}/{{#lambda.snakecase}}{{classname}}{{/lambda.sn
     {{/apiInfo}}
 
 module Adyen
+
+  # NOTE: This class is auto generated by OpenAPI Generator
+  # Ref: https://openapi-generator.tech
+  #
+  # Do not edit the class manually.
   class {{#lambda.titlecase}}{{serviceName}}{{/lambda.titlecase}}
     attr_accessor :service, :version