diff --git a/api/client-server/redaction.yaml b/api/client-server/redaction.yaml
index 752d841a5..581410492 100644
--- a/api/client-server/redaction.yaml
+++ b/api/client-server/redaction.yaml
@@ -79,7 +79,7 @@ paths:
           description: "An ID for the redaction event."
           examples:
             application/json: {
-                  "event_id": "YUwQidLecu"
+                  "event_id": "$YUwQidLecu:example.com"
               }
           schema:
             type: object
diff --git a/api/client-server/room_send.yaml b/api/client-server/room_send.yaml
index 0bb1bbcb9..6963f76c0 100644
--- a/api/client-server/room_send.yaml
+++ b/api/client-server/room_send.yaml
@@ -76,7 +76,7 @@ paths:
           description: "An ID for the sent event."
           examples:
             application/json: {
-                  "event_id": "YUwRidLecu"
+                  "event_id": "$YUwRidLecu:example.com"
               }
           schema:
             type: object
diff --git a/api/client-server/room_state.yaml b/api/client-server/room_state.yaml
index 042b5eedf..c04fb8039 100644
--- a/api/client-server/room_state.yaml
+++ b/api/client-server/room_state.yaml
@@ -78,7 +78,7 @@ paths:
           description: "An ID for the sent event."
           examples:
             application/json: {
-                  "event_id": "YUwRidLecu"
+                  "event_id": "$YUwRidLecu:example.com"
               }
           schema:
             type: object
@@ -133,7 +133,7 @@ paths:
           description: "An ID for the sent event."
           examples:
             application/json: {
-                  "event_id": "YUwRidLecu"
+                  "event_id": "$YUwRidLecu:example.com"
               }
           schema:
             type: object