Use <zone> instead of <zone> if the parameter is mandatory

doc/running.rst

@@ -51,13 +51,13 @@ If you want to control the daemon directly, use ``SIGINT`` to quit the process o
     Actions:
      stop                   Stop server.
      reload                 Reload configuration and changed zones.
-     refresh [zone]         Refresh slave zone (all if not specified).
+     refresh <zone>         Refresh slave zone (all if not specified).
      flush                  Flush journal and update zone files.
      status                 Check if server is running.
      zonestatus             Show status of configured zones.
      checkconf              Check current server configuration.
-     checkzone [zone]       Check zone (all if not specified).
-     memstats [zone]        Estimate memory consumption for zone (all if not
+     checkzone <zone>       Check zone (all if not specified).
+     memstats <zone>        Estimate memory consumption for zone (all if not
                             specified).
 
 Also, the server needs to create several files in order to run properly. These

src/knot/ctl/knotc_main.c

@@ -80,14 +80,14 @@ static int cmd_signzone(int argc, char *argv[], unsigned flags);
 knot_cmd_t knot_cmd_tbl[] = {
 	{&cmd_stop,       0, "stop",       "",       "\t\tStop server."},
 	{&cmd_reload,     0, "reload",     "",       "\tReload configuration and changed zones."},
-	{&cmd_refresh,    0, "refresh",    "[zone]", "\tRefresh slave zone (all if not specified). Flag '-f' forces retransfer."},
+	{&cmd_refresh,    0, "refresh",    "<zone>", "\tRefresh slave zone (all if not specified). Flag '-f' forces retransfer."},
 	{&cmd_flush,      0, "flush",      "",       "\t\tFlush journal and update zone files."},
 	{&cmd_status,     0, "status",     "",       "\tCheck if server is running."},
 	{&cmd_zonestatus, 0, "zonestatus", "",       "\tShow status of configured zones."},
 	{&cmd_checkconf,  1, "checkconf",  "",       "\tCheck current server configuration."},
-	{&cmd_checkzone,  1, "checkzone",  "[zone]", "Check zone (all if not specified)."},
-	{&cmd_memstats,   1, "memstats",   "[zone]", "Estimate memory use for zone (all if not specified)."},
-	{&cmd_signzone,   0, "signzone",   "[zone]", "Sign all zones with available DNSSEC keys."},
+	{&cmd_checkzone,  1, "checkzone",  "<zone>", "Check zone (all if not specified)."},
+	{&cmd_memstats,   1, "memstats",   "<zone>", "Estimate memory use for zone (all if not specified)."},
+	{&cmd_signzone,   0, "signzone",   "<zone>", "Sign all zones with available DNSSEC keys."},
 	{NULL, 0, NULL, NULL, NULL}
 };