diff --git a/sdk/go-sdk/client/subscribe.go b/sdk/go-sdk/client/subscribe.go
deleted file mode 100644
index e6ee13634b..0000000000
--- a/sdk/go-sdk/client/subscribe.go
+++ /dev/null
@@ -1,207 +0,0 @@
-package client
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"sync"
-	"sync/atomic"
-
-	runtimev1pb "mosn.io/layotto/spec/proto/runtime/v1"
-)
-
-const (
-	// SubscriptionResponseStatusSuccess means message is processed successfully.
-	SubscriptionResponseStatusSuccess SubscriptionResponseStatus = "SUCCESS"
-	// SubscriptionResponseStatusRetry means message to be retried by Dapr.
-	SubscriptionResponseStatusRetry SubscriptionResponseStatus = "RETRY"
-	// SubscriptionResponseStatusDrop means warning is logged and message is dropped.
-	SubscriptionResponseStatusDrop SubscriptionResponseStatus = "DROP"
-)
-
-type SubscriptionResponseStatus string
-
-type SubscriptionResponse struct {
-	Status SubscriptionResponseStatus `json:"status"`
-}
-
-type SubscriptionHandleFunction func(request *runtimev1pb.TopicEventRequest) SubscriptionResponseStatus
-
-type SubscriptionRequest struct {
-	PubsubName      string
-	Topic           string
-	DeadLetterTopic *string
-	Metadata        map[string]string
-}
-
-type Subscription struct {
-	stream runtimev1pb.Runtime_SubscribeTopicEventsClient
-	// lock locks concurrent writes to subscription stream.
-	lock   sync.Mutex
-	closed atomic.Bool
-}
-
-type SubscriptionMessage struct {
-	*runtimev1pb.TopicEventRequest
-	sub *Subscription
-}
-
-func (c *GRPCClient) Subscribe(ctx context.Context, request SubscriptionRequest) (*Subscription, error) {
-	stream, err := c.subscribeInitialRequest(ctx, request)
-	if err != nil {
-		return nil, err
-	}
-
-	s := &Subscription{
-		stream: stream,
-	}
-
-	return s, nil
-}
-
-func (c *GRPCClient) SubscribeWithHandler(ctx context.Context, request SubscriptionRequest, handler SubscriptionHandleFunction) (func() error, error) {
-	s, err := c.Subscribe(ctx, request)
-	if err != nil {
-		return nil, err
-	}
-
-	go func() {
-		defer s.Close()
-
-		for {
-			msg, err := s.Receive()
-			if err != nil {
-				if !s.closed.Load() {
-					logger.Printf("Error receiving messages from subscription pubsub=%s topic=%s, closing subscription: %s",
-						request.PubsubName, request.Topic, err)
-				}
-				return
-			}
-
-			go func() {
-				if err := msg.respondStatus(handler(msg.TopicEventRequest)); err != nil {
-					logger.Printf("Error responding to topic with event status pubsub=%s topic=%s message_id=%s: %s",
-						request.PubsubName, request.Topic, msg.Id, err)
-				}
-			}()
-		}
-	}()
-
-	return s.Close, nil
-}
-
-func (s *Subscription) Close() error {
-	if !s.closed.CompareAndSwap(false, true) {
-		return errors.New("subscription already closed")
-	}
-
-	return s.stream.CloseSend()
-}
-
-func (s *Subscription) Receive() (*SubscriptionMessage, error) {
-	resp, err := s.stream.Recv()
-	if err != nil {
-		return nil, err
-	}
-	event := resp.GetEventMessage()
-
-	eventRequest := &runtimev1pb.TopicEventRequest{
-		Id:              event.GetId(),
-		Source:          event.GetSource(),
-		Type:            event.GetType(),
-		SpecVersion:     event.GetSpecVersion(),
-		DataContentType: event.GetDataContentType(),
-		Data:            event.GetData(),
-		Topic:           event.GetTopic(),
-		PubsubName:      event.GetPubsubName(),
-	}
-
-	return &SubscriptionMessage{
-		sub:               s,
-		TopicEventRequest: eventRequest,
-	}, nil
-}
-
-func (s *SubscriptionMessage) Success() error {
-	return s.respond(runtimev1pb.TopicEventResponse_SUCCESS)
-}
-
-func (s *SubscriptionMessage) Retry() error {
-	return s.respond(runtimev1pb.TopicEventResponse_RETRY)
-}
-
-func (s *SubscriptionMessage) Drop() error {
-	return s.respond(runtimev1pb.TopicEventResponse_DROP)
-}
-
-func (s *SubscriptionMessage) respondStatus(status SubscriptionResponseStatus) error {
-	var statuspb runtimev1pb.TopicEventResponse_TopicEventResponseStatus
-	switch status {
-	case SubscriptionResponseStatusSuccess:
-		statuspb = runtimev1pb.TopicEventResponse_SUCCESS
-	case SubscriptionResponseStatusRetry:
-		statuspb = runtimev1pb.TopicEventResponse_RETRY
-	case SubscriptionResponseStatusDrop:
-		statuspb = runtimev1pb.TopicEventResponse_DROP
-	default:
-		return fmt.Errorf("unknown status, expected one of %s, %s, %s: %s",
-			SubscriptionResponseStatusSuccess, SubscriptionResponseStatusRetry,
-			SubscriptionResponseStatusDrop, status)
-	}
-
-	return s.respond(statuspb)
-}
-
-func (s *SubscriptionMessage) respond(status runtimev1pb.TopicEventResponse_TopicEventResponseStatus) error {
-	s.sub.lock.Lock()
-	defer s.sub.lock.Unlock()
-
-	return s.sub.stream.Send(&runtimev1pb.SubscribeTopicEventsRequest{
-		SubscribeTopicEventsRequestType: &runtimev1pb.SubscribeTopicEventsRequest_EventProcessed{
-			EventProcessed: &runtimev1pb.SubscribeTopicEventsRequestProcessed{
-				Id:     s.Id,
-				Status: &runtimev1pb.TopicEventResponse{Status: status},
-			},
-		},
-	})
-}
-
-func (c *GRPCClient) subscribeInitialRequest(ctx context.Context, request SubscriptionRequest) (runtimev1pb.Runtime_SubscribeTopicEventsClient, error) {
-	if len(request.PubsubName) == 0 {
-		return nil, errors.New("pubsub name required")
-	}
-
-	if len(request.Topic) == 0 {
-		return nil, errors.New("topic required")
-	}
-
-	stream, err := c.protoClient.SubscribeTopicEvents(ctx)
-	if err != nil {
-		return nil, err
-	}
-
-	err = stream.Send(&runtimev1pb.SubscribeTopicEventsRequest{
-		SubscribeTopicEventsRequestType: &runtimev1pb.SubscribeTopicEventsRequest_InitialRequest{
-			InitialRequest: &runtimev1pb.SubscribeTopicEventsRequestInitial{
-				PubsubName: request.PubsubName, Topic: request.Topic,
-				Metadata: request.Metadata, DeadLetterTopic: request.DeadLetterTopic,
-			},
-		},
-	})
-	if err != nil {
-		return nil, errors.Join(err, stream.CloseSend())
-	}
-
-	resp, err := stream.Recv()
-	if err != nil {
-		return nil, errors.Join(err, stream.CloseSend())
-	}
-
-	switch resp.GetSubscribeTopicEventsResponseType().(type) {
-	case *runtimev1pb.SubscribeTopicEventsResponse_InitialResponse:
-	default:
-		return nil, fmt.Errorf("unexpected initial response from server : %v", resp)
-	}
-
-	return stream, nil
-}
diff --git a/spec/proto/runtime/v1/runtime.proto b/spec/proto/runtime/v1/runtime.proto
index 381d99646e..b1b6459f7a 100644
--- a/spec/proto/runtime/v1/runtime.proto
+++ b/spec/proto/runtime/v1/runtime.proto
@@ -4,7 +4,7 @@ package spec.proto.runtime.v1;
 
 import "google/protobuf/empty.proto";
 import "google/protobuf/any.proto";
-import "appcallback.proto";
+import "spec/proto/runtime/v1/appcallback.proto";
 
 option go_package = "mosn.io/layotto/spec/proto/runtime/v1;runtime";
 option java_outer_classname = "RuntimeProto";