diff --git a/docs/sending/start-submission.mdx b/docs/sending/start-submission.mdx
index 071dc90163760368c7b960ea1870708fa13f2305..d53046744f4adb50cd18a220b0eeb5e9ebd66e02 100644
--- a/docs/sending/start-submission.mdx
+++ b/docs/sending/start-submission.mdx
@@ -55,6 +55,10 @@ $ curl -L -X POST "$SUBMISSION_API/v1/submissions" \
     \"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\"
     }
 }"
 ```