diff --git a/app/main.go b/app/main.go
index cc349d4..92fd312 100644
--- a/app/main.go
+++ b/app/main.go
@@ -1,7 +1,9 @@
 package main
 
 import (
+	"fmt"
 	"os"
+	"strings"
 	"time"
 
 	"github.com/yedf/dtm/dtmcli"
@@ -19,6 +21,25 @@ func wait() {
 }
 
 func main() {
+	if len(os.Args) == 1 {
+		for _, ln := range []string{
+			"dtm is a lightweight distributed transaction manager.",
+			"usage:",
+			"dtm [command]",
+			"",
+			"Available Commands:",
+			"dtmsvr            run dtm as a server. ",
+			"",
+			"quick_start       run quick start example. dtm will create all needed table",
+			"qs                same as quick_start",
+		} {
+			fmt.Print(ln + "\n")
+		}
+		for name := range examples.Samples {
+			fmt.Printf("%-18srun a sample includes %s\n", name, strings.Replace(name, "_", " ", 100))
+		}
+		return
+	}
 	onlyServer := len(os.Args) > 1 && os.Args[1] == "dtmsvr"
 	if !onlyServer { // 实际线上运行，只启动dtmsvr，不准备table相关的数据
 		dtmsvr.PopulateDB(true)
@@ -43,8 +64,8 @@ func main() {
 	examples.GrpcStartup()
 	examples.BaseAppStartup()
 
-	fn := examples.Samples[os.Args[1]]
-	dtmcli.LogIfFatalf(fn == nil, "no sample name for %s", os.Args[1])
-	fn()
+	sample := examples.Samples[os.Args[1]]
+	dtmcli.LogIfFatalf(sample == nil, "no sample name for %s", os.Args[1])
+	sample.Action()
 	wait()
 }
diff --git a/common/types.go b/common/types.go
index 65bf92b..6e26204 100644
--- a/common/types.go
+++ b/common/types.go
@@ -131,6 +131,9 @@ type dtmConfigType struct {
 var DtmConfig = dtmConfigType{}
 
 func init() {
+	if len(os.Args) == 1 {
+		return
+	}
 	DtmConfig.TransCronInterval = int64(dtmcli.MustAtoi(dtmcli.OrString(os.Getenv("TRANS_CRON_INTERVAL"), "10")))
 	DtmConfig.DB = map[string]string{
 		"driver":   dtmcli.OrString(os.Getenv("DB_DRIVER"), "mysql"),
diff --git a/examples/data.go b/examples/data.go
index 9313e81..ac62da1 100644
--- a/examples/data.go
+++ b/examples/data.go
@@ -37,12 +37,16 @@ func PopulateDB(skipDrop bool) {
 	RunSQLScript(config.DB, file, skipDrop)
 }
 
+type sampleInfo struct {
+	Arg    string
+	Action func() string
+	Desc   string
+}
+
 // Samples 所有的示例都会注册到这里
-var Samples = map[string]func() string{}
+var Samples = map[string]*sampleInfo{}
 
 func addSample(name string, fn func() string) {
-	if Samples[name] != nil {
-		dtmcli.LogFatalf("sample %s duplicated", name)
-	}
-	Samples[name] = fn
+	dtmcli.LogIfFatalf(Samples[name] != nil, "%s already exists")
+	Samples[name] = &sampleInfo{Arg: name, Action: fn}
 }
diff --git a/test/examples_test.go b/test/examples_test.go
index 7b3e044..059f803 100644
--- a/test/examples_test.go
+++ b/test/examples_test.go
@@ -9,7 +9,7 @@ import (
 func TestExamples(t *testing.T) {
 	// for coverage
 	examples.QsStartSvr()
-	for _, fn := range examples.Samples {
-		assertSucceed(t, fn())
+	for _, s := range examples.Samples {
+		assertSucceed(t, s.Action())
 	}
 }