diff --git a/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Publisher.java b/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Publisher.java
index 7b5265548a7f..027da1a5ddd6 100644
--- a/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Publisher.java
+++ b/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Publisher.java
@@ -70,8 +70,9 @@
  *   <li>Retries: such as the maximum duration of retries for a failing batch of messages.
  * </ul>
  *
- * <p>If no credentials are provided, the {@link Publisher} will use application default credentials
- * through {@link GoogleCredentials#getApplicationDefault}.
+ * <p>{@link Publisher} will use the credentials set on the channel, which uses
+ *  application default credentials through {@link GoogleCredentials#getApplicationDefault}
+ *  by default.
  */
 public class Publisher {
   private static final Logger logger = Logger.getLogger(Publisher.class.getName());
diff --git a/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Subscriber.java b/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Subscriber.java
index b0dd5acc9922..128dbfcdeb0b 100644
--- a/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Subscriber.java
+++ b/google-cloud-pubsub/src/main/java/com/google/cloud/pubsub/spi/v1/Subscriber.java
@@ -71,8 +71,9 @@
  *       in memory before the receiver either ack or nack them.
  * </ul>
  *
- * <p>If no credentials are provided, the {@link Subscriber} will use application default
- * credentials through {@link GoogleCredentials#getApplicationDefault}.
+ * <p>{@link Subscriber} will use the credentials set on the channel, which uses
+ *  application default credentials through {@link GoogleCredentials#getApplicationDefault}
+ *  by default.
  */
 public class Subscriber extends AbstractApiService {
   private static final int THREADS_PER_CHANNEL = 5;