diff --git a/README.md b/README.md
index 4d3412a..f1fb0b3 100644
--- a/README.md
+++ b/README.md
@@ -20,15 +20,15 @@ The DNS update requests are retried in the background (XXX: currently blocks for
 	  -v, --verbose
 		  --watch                                           Watch for interface changes
 	  -i, --interface=IFACE                                 Use address from interface
-		  --interface-family=ipv4|ipv6|all
-		  --server=HOST[:PORT]
-		  --timeout=DURATION
-		  --retry=DURATION
+		  --interface-family=ipv4|ipv6|all                  Limit to interface addreses of given family
+		  --server=HOST[:PORT]                              Server for UPDATE query, default is discovered from zone SOA
+		  --timeout=DURATION                                Timeout for sever queries (default: 10s)
+		  --retry=DURATION                                  Retry interval, increased for each retry attempt (default: 30s)
 		  --tsig-name=FQDN
-		  --tsig-secret=BASE-64
+		  --tsig-secret=BASE-64                             base64-encoded shared TSIG secret key [$TSIG_SECRET]
 		  --tsig-algorithm=hmac-{md5,sha1,sha256,sha512}
-		  --zone=FQDN                                       Zone to update
-		  --ttl=DURATION
+		  --zone=FQDN                                       Zone to update, default is derived from name
+		  --ttl=DURATION                                    TTL for updated records (default: 60s)
 
 	Help Options:
 	  -h, --help                                            Show this help message
@@ -36,6 +36,7 @@ The DNS update requests are retried in the background (XXX: currently blocks for
 	Arguments:
 	  Name:                                                 DNS Name to update
 
+
 ## Example
     
     # Using a generated TSIG key:
diff --git a/main.go b/main.go
index 5b1de11..6cc5b0c 100644
--- a/main.go
+++ b/main.go
@@ -12,20 +12,20 @@ type Options struct {
 	Watch			bool	`long:"watch" description:"Watch for interface changes"`
 
 	Interface		string	`long:"interface" short:"i" value-name:"IFACE" description:"Use address from interface"`
-	InterfaceFamily	Family	`long:"interface-family" value-name:"ipv4|ipv6|all"`
+	InterfaceFamily	Family	`long:"interface-family" value-name:"ipv4|ipv6|all" description:"Limit to interface addreses of given family"`
 
-	Server		string	`long:"server" value-name:"HOST[:PORT]"`
-	Timeout		time.Duration `long:"timeout" value-name:"DURATION" default:"10s"`
-	Retry		time.Duration `long:"retry" value-name:"DURATION" default:"30s"`
+	Server		string	`long:"server" value-name:"HOST[:PORT]" description:"Server for UPDATE query, default is discovered from zone SOA"`
+	Timeout		time.Duration `long:"timeout" value-name:"DURATION" default:"10s" description:"Timeout for sever queries"`
+	Retry		time.Duration `long:"retry" value-name:"DURATION" default:"30s" description:"Retry interval, increased for each retry attempt"`
 	TSIGName	string	`long:"tsig-name" value-name:"FQDN"`
-	TSIGSecret	string	`long:"tsig-secret" value-name:"BASE-64" env:"TSIG_SECRET"`
+	TSIGSecret	string	`long:"tsig-secret" value-name:"BASE-64" env:"TSIG_SECRET" description:"base64-encoded shared TSIG secret key"`
 	TSIGAlgorithm TSIGAlgorithm `long:"tsig-algorithm" value-name:"hmac-{md5,sha1,sha256,sha512}" default:"hmac-sha1."`
 
-	Zone		string	`long:"zone" value-name:"FQDN" description:"Zone to update"`
-	TTL			time.Duration `long:"ttl" value-name:"DURATION" default:"60s"`
+	Zone		string	`long:"zone" value-name:"FQDN" description:"Zone to update, default is derived from name"`
+	TTL			time.Duration `long:"ttl" value-name:"DURATION" default:"60s" description:"TTL for updated records"`
 
 	Args		struct {
-		Name		string	`description:"DNS Name to update"`
+		Name		string	`value-name:"FQDN" description:"DNS Name to update"`
 	} `positional-args:"yes"`
 }