diff --git a/include/olm/account.hh b/include/olm/account.hh
index dd115f5..50708ed 100644
--- a/include/olm/account.hh
+++ b/include/olm/account.hh
@@ -107,8 +107,10 @@ struct Account {
         std::uint8_t * one_time_json, std::size_t one_time_json_length
     );
 
-    /** Mark the current list of one_time_keys as being published. They
-     * will no longer be returned by get_one_time_keys_json_length(). */
+    /** Mark the current list of one_time_keys and the current fallback key as
+     * being published. The current one time keys will no longer be returned by
+     * get_one_time_keys_json() and the current fallback key will no longer be
+     * returned by get_unpublished_fallback_key_json(). */
     std::size_t mark_keys_as_published();
 
     /** The largest number of one time keys this account can store. */
diff --git a/include/olm/olm.h b/include/olm/olm.h
index 9e02440..d5927e4 100644
--- a/include/olm/olm.h
+++ b/include/olm/olm.h
@@ -245,7 +245,13 @@ OLM_EXPORT size_t olm_account_one_time_keys(
     void * one_time_keys, size_t one_time_keys_length
 );
 
-/** Marks the current set of one time keys as being published. */
+/** Marks the current set of one time keys and fallback key as being published
+ * Once marked as published, the one time keys will no longer be returned by
+ * olm_account_one_time_keys(), and the fallback key will no longer be returned
+ * by olm_account_unpublished_fallback_key().
+ *
+ * Returns the number of one-time keys that were marked as published.  Note that
+ * this count does not include the fallback key. */
 OLM_EXPORT size_t olm_account_mark_keys_as_published(
     OlmAccount * account
 );