diff --git a/docs/sending/start-submission.mdx b/docs/sending/start-submission.mdx
index d53046744f4adb50cd18a220b0eeb5e9ebd66e02..50ad701f4c4248f998e32aff6febcd11ddfe6fc8 100644
--- a/docs/sending/start-submission.mdx
+++ b/docs/sending/start-submission.mdx
@@ -88,6 +88,10 @@ const data = JSON.stringify({
   "serviceType": {
     "name": "Antrag Name",
     "identifier": "urn:de:fim:leika:leistung:99102013104000"
+  },
+  "callback": {
+    "url": "https://my-onlineservice.example.org/callbacks/fit-connect",
+    "secret": "insecure_unsafe_qHScgrg_kP-R31jHUwp3GkVkGJolvBchz65b74Lzue0"
   }
 });