@@ -1267,6 +1267,9 @@ func ListenAndServe(proto, addr string, job *engine.Job) error {

 // ServeApi loops through all of the protocols sent in to docker and spawns

 // off a go routine to setup a serving http.Server for each.

 func ServeApi(job *engine.Job) engine.Status {

+	if len(job.Args) == 0 {

+		return job.Errorf("usage: %s PROTO://ADDR [PROTO://ADDR ...]", job.Name)

+	}

 	var (

 		protoAddrs = job.Args

 		chErrors   = make(chan error, len(protoAddrs))

@@ -1279,6 +1282,9 @@ func ServeApi(job *engine.Job) engine.Status {

 	for _, protoAddr := range protoAddrs {

 		protoAddrParts := strings.SplitN(protoAddr, "://", 2)

+		if len(protoAddrParts) != 2 {

+			return job.Errorf("usage: %s PROTO://ADDR [PROTO://ADDR ...]", job.Name)

+		}

 		go func() {

 			log.Printf("Listening for HTTP on %s (%s)\n", protoAddrParts[0], protoAddrParts[1])

 			chErrors <- ListenAndServe(protoAddrParts[0], protoAddrParts[1], job)