diff --git a/rmw/include/rmw/get_topic_endpoint_info.h b/rmw/include/rmw/get_topic_endpoint_info.h
index bde2ffad..b2210959 100644
--- a/rmw/include/rmw/get_topic_endpoint_info.h
+++ b/rmw/include/rmw/get_topic_endpoint_info.h
@@ -31,6 +31,14 @@ extern "C"
  * the associated topic type, the publisher's gid, and the publisher QoS profile.
  * Names of non-existent topics are allowed, in which case an empty array will be returned.
  *
+ * \par QoS that are correctly read
+ * The QoS profiles returned might have some invalid fields.
+ * The rmw implementation must set the invalid fields to `RMW_QOS_POLICY_*_UNKNOWN`.
+ * For DDS based implementations, the only QoS policies that are guaranteed to be shared
+ * during discovery are the ones that participate in endpoint matching.
+ * From the current QoS settings available, the only ones not shared by DDS based
+ * implementations are `history` and `history_depth`.
+ *
  * <hr>
  * Attribute          | Adherence
  * ------------------ | -------------
@@ -105,6 +113,9 @@ rmw_get_publishers_info_by_topic(
  * the associated topic type, the subscription's gid, and the subscription QoS profile.
  * Names of non-existent topics are allowed, in which case an empty array will be returned.
  *
+ * \par QoS that are correctly read
+ * Not all QoS may be read correctly, \sa rmw_get_publishers_info_by_topic() for more details.
+ *
  * <hr>
  * Attribute          | Adherence
  * ------------------ | -------------