diff --git a/google/pubsub/v1/pubsub_gapic.yaml b/google/pubsub/v1/pubsub_gapic.yaml
index f012bd625..3b1e31783 100644
--- a/google/pubsub/v1/pubsub_gapic.yaml
+++ b/google/pubsub/v1/pubsub_gapic.yaml
@@ -238,6 +238,8 @@ interfaces:
         subresponse_field: message_ids
     field_name_patterns:
       topic: topic
+    sample_code_init_fields:
+      - messages[0].data
   - name: GetTopic
     flattening:
       groups: