diff --git a/conf/full.config b/conf/full.config
index 55f14fc2a..24dfc2a80 100644
--- a/conf/full.config
+++ b/conf/full.config
@@ -55,7 +55,7 @@ rpc_encoding = gob # Use json or gob for RPC encoding
 [freeswitch]
 server = localhost:8021 # Freeswitch address host:port
 pass = ClueCon # Freeswtch address host:port
-direction_index = 0
+direction_index = 0 # the position of elements in the Master.csv file
 tor_index = 1
 tenant_index = 2
 subject_index = 3