diff --git a/srv/TSTExecute.srv b/srv/TSTExecute.srv
index acc4af12e00db7afe57066a18b9992e7d240eaa4..75bca5d824cfb87b743d7acc0b6e9f41af5969a9 100644
--- a/srv/TSTExecute.srv
+++ b/srv/TSTExecute.srv
@@ -1,6 +1,7 @@
 # Start execution of TST.  The returned uuid can be used to check status of execution.
 
 string json_tst         # JSON for the tree to be executed
+int32 channel           # Channel to disply TST on
 ---
 string uuid
 bool success