diff --git a/scripts/snmp-sysdescr.nse b/scripts/snmp-sysdescr.nse
index d00fbcedf..13e635065 100644
--- a/scripts/snmp-sysdescr.nse
+++ b/scripts/snmp-sysdescr.nse
@@ -3,7 +3,8 @@ Attempts to extract system information from an SNMP version 1 service.
 ]]
 
 ---
--- @args snmpcommunity The community string to use.
+-- @args snmpcommunity The community string to use. If not supplied, it is
+-- <code>public</code>.
 -- 
 -- @output
 -- |  snmp-sysdescr: HP ETHERNET MULTI-ENVIRONMENT,ROM A.25.80,JETDIRECT,JD117,EEPROM V.28.22,CIDATE 08/09/2006