diff --git a/ts/00_commitinfo_data.ts b/ts/00_commitinfo_data.ts
index 7aa8d72..563cfe7 100644
--- a/ts/00_commitinfo_data.ts
+++ b/ts/00_commitinfo_data.ts
@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@serve.zone/interfaces',
-  version: '1.0.34',
+  version: '1.0.35',
   description: 'interfaces for working with containers'
 }
diff --git a/ts/platformservice/letter.ts b/ts/platformservice/letter.ts
index ec7820f..9d94127 100644
--- a/ts/platformservice/letter.ts
+++ b/ts/platformservice/letter.ts
@@ -6,10 +6,19 @@ export interface IRequest_SendLetter extends plugins.typedrequestInterfaces.impl
 > {
   method: 'sendLetter';
   request: {
-    title: string;
-    from: plugins.tsclass.business.IAddress;
-    to: plugins.tsclass.business.IAddress;
-    body: string;
+    /**
+     * will be used in logs
+     */
+    description: string;
+    /**
+     * if you send any PDF / invoice that you have not made sure to be letterxpress compliant
+     * we strongly recommend using a cover page
+     */
+    needsCover: boolean;
+    title?: string;
+    from?: plugins.tsclass.business.IAddress;
+    to?: plugins.tsclass.business.IAddress;
+    coverBody?: string;
     service: ('Einschreiben')[];
     pdfAttachments?: Array<{
       name: string;