diff --git a/app/proxyman/mux/mux.go b/app/proxyman/mux/mux.go
index a87847584..be2e4c014 100644
--- a/app/proxyman/mux/mux.go
+++ b/app/proxyman/mux/mux.go
@@ -310,10 +310,12 @@ func NewServer(ctx context.Context) *Server {
 	return s
 }
 
+// Type implements common.HasType.
 func (s *Server) Type() interface{} {
 	return s.dispatcher.Type()
 }
 
+// Dispatch impliments routing.Dispatcher
 func (s *Server) Dispatch(ctx context.Context, dest net.Destination) (*vio.Link, error) {
 	if dest.Address != muxCoolAddress {
 		return s.dispatcher.Dispatch(ctx, dest)
diff --git a/transport/internet/dialer.go b/transport/internet/dialer.go
index e5bd13c0d..efe355228 100644
--- a/transport/internet/dialer.go
+++ b/transport/internet/dialer.go
@@ -3,17 +3,18 @@ package internet
 import (
 	"context"
 
-	"v2ray.com/core/common/session"
-
 	"v2ray.com/core/common/net"
+	"v2ray.com/core/common/session"
 )
 
+// Dialer is an interface to dial network connection to a specific destination.
 type Dialer func(ctx context.Context, dest net.Destination) (Connection, error)
 
 var (
 	transportDialerCache = make(map[string]Dialer)
 )
 
+// RegisterTransportDialer registers a Dialer with given name.
 func RegisterTransportDialer(protocol string, dialer Dialer) error {
 	if _, found := transportDialerCache[protocol]; found {
 		return newError(protocol, " dialer already registered").AtError()
diff --git a/transport/internet/memory_settings.go b/transport/internet/memory_settings.go
index dc7aa4017..3c4770d2f 100644
--- a/transport/internet/memory_settings.go
+++ b/transport/internet/memory_settings.go
@@ -1,5 +1,6 @@
 package internet
 
+// MemoryStreamConfig is a parsed form of StreamConfig. This is used to reduce number of Protobuf parsing.
 type MemoryStreamConfig struct {
 	ProtocolName     string
 	ProtocolSettings interface{}
@@ -8,6 +9,7 @@ type MemoryStreamConfig struct {
 	SocketSettings   *SocketConfig
 }
 
+// ToMemoryStreamConfig converts a StreamConfig to MemoryStreamConfig. It returns a default non-nil MemoryStreamConfig for nil input.
 func ToMemoryStreamConfig(s *StreamConfig) (*MemoryStreamConfig, error) {
 	ets, err := s.GetEffectiveTransportSettings()
 	if err != nil {