diff --git a/include/sxmp/sxmp.h b/include/sxmp/sxmp.h
index aa07186..d1025ea 100644
--- a/include/sxmp/sxmp.h
+++ b/include/sxmp/sxmp.h
@@ -174,13 +174,18 @@ typedef struct __link_rpc_list_type {
 
 struct sxstream_ops;
 
+/*
+ * description of the stream
+ * located on the master and client,
+ * client will get it after sync
+ */
 struct sxstream_description {
-  uint16_t stid;
-  uint16_t pcid;
-  uint16_t type;
-  uint16_t flags;
-  struct sxstream_ops *ops;
-  usrtc_node_t node;
+  uint16_t stid; /** < stream type ID */
+  uint16_t pcid; /** < pinned channel type ID */
+  uint16_t type; /** < type: 0||SXE_O_NAMED||SXE_O_BINARY */
+  uint16_t flags; /** < possible flags */
+  struct sxstream_ops *ops; /** < operations */
+  usrtc_node_t node; /** < internal node struct */
 };
 
 struct sxstream_opened {