diff --git a/aggregatedpool/workflow.go b/aggregatedpool/workflow.go
index bee62a44..8e38c057 100644
--- a/aggregatedpool/workflow.go
+++ b/aggregatedpool/workflow.go
@@ -1,6 +1,7 @@
 package aggregatedpool
 
 import (
+	"fmt"
 	"sync/atomic"
 	"time"
 
@@ -149,6 +150,10 @@ func (wp *Workflow) OnWorkflowTaskStarted(t time.Duration) {
 		wp.pipeline = wp.pipeline[1:]
 
 		if msg.IsCommand() {
+			if msg.UndefinedResponse() {
+				panic(fmt.Sprintf("undefined response: %s", msg.Command.(*internal.UndefinedResponse).Message))
+			}
+
 			err = wp.handleMessage(msg)
 		}
 
diff --git a/go.mod b/go.mod
index 38e63a5a..4204201e 100644
--- a/go.mod
+++ b/go.mod
@@ -9,7 +9,7 @@ require (
 	github.com/google/uuid v1.3.0
 	github.com/roadrunner-server/endure/v2 v2.2.0
 	github.com/roadrunner-server/errors v1.2.0
-	github.com/roadrunner-server/sdk/v4 v4.1.0
+	github.com/roadrunner-server/sdk/v4 v4.2.0
 	github.com/stretchr/testify v1.8.1
 	github.com/uber-go/tally/v4 v4.1.6
 	go.temporal.io/api v1.17.0
@@ -40,7 +40,7 @@ require (
 	github.com/prometheus/common v0.39.0 // indirect
 	github.com/prometheus/procfs v0.9.0 // indirect
 	github.com/roadrunner-server/goridge/v3 v3.6.2 // indirect
-	github.com/roadrunner-server/tcplisten v1.2.1 // indirect
+	github.com/roadrunner-server/tcplisten v1.3.0 // indirect
 	github.com/robfig/cron v1.2.0 // indirect
 	github.com/rogpeppe/go-internal v1.9.0 // indirect
 	github.com/shirou/gopsutil v3.21.11+incompatible // indirect
@@ -51,7 +51,7 @@ require (
 	github.com/yusufpapurcu/wmi v1.2.2 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	go.uber.org/multierr v1.9.0 // indirect
-	golang.org/x/net v0.6.0 // indirect
+	golang.org/x/net v0.7.0 // indirect
 	golang.org/x/sync v0.1.0 // indirect
 	golang.org/x/sys v0.5.0 // indirect
 	golang.org/x/text v0.7.0 // indirect
diff --git a/go.sum b/go.sum
index 19ed1272..e4ec1664 100644
--- a/go.sum
+++ b/go.sum
@@ -642,10 +642,10 @@ github.com/roadrunner-server/errors v1.2.0 h1:qBmNXt8Iex9QnYTjCkbJKsBZu2EtYkQCM0
 github.com/roadrunner-server/errors v1.2.0/go.mod h1:z0ECxZp/dDa5RahtMcy4mBIavVxiZ9vwE5kByl7kFtY=
 github.com/roadrunner-server/goridge/v3 v3.6.2 h1:LH5HXfCygDp05KnOaXpa4fqVPWTsH7V3lfvPtMwFU3k=
 github.com/roadrunner-server/goridge/v3 v3.6.2/go.mod h1:3B95k/wM5GGAD0h2hZlJagS9PlTDGs5jh8MpZYC12vA=
-github.com/roadrunner-server/sdk/v4 v4.1.0 h1:akICxF9GQOHggvHW01Try5QiRmr2IrCN0RYWHyGdjDQ=
-github.com/roadrunner-server/sdk/v4 v4.1.0/go.mod h1:aIzXmg8DZBJ4Tbtvihp/s6VH4e2oSdivOqm/8V+HuUc=
-github.com/roadrunner-server/tcplisten v1.2.1 h1:9hVVMlCRvMPewnJCnfSe/kKAqn2ZOF3wHy+ji0M/NKU=
-github.com/roadrunner-server/tcplisten v1.2.1/go.mod h1:TRJLGwIruiJ7QhmGVRgJFY5Ch72mPoLhLAxuxLnavpU=
+github.com/roadrunner-server/sdk/v4 v4.2.0 h1:hqNlqJV2MXZ8DF1wJnouUdV/55Hae6VL37fVXT1aIr8=
+github.com/roadrunner-server/sdk/v4 v4.2.0/go.mod h1:aIzXmg8DZBJ4Tbtvihp/s6VH4e2oSdivOqm/8V+HuUc=
+github.com/roadrunner-server/tcplisten v1.3.0 h1:VDd6IbP8oIjm5vKvMVozeZgeHgOcoP0XYLOyOqcZHCY=
+github.com/roadrunner-server/tcplisten v1.3.0/go.mod h1:VR6Ob5am0oEuLMOeLiVvQxG9ShykAEgrlvZddX8EfoU=
 github.com/robfig/cron v1.2.0 h1:ZjScXvvxeQ63Dbyxy76Fj3AT3Ut0aKsyd2/tl3DTMuQ=
 github.com/robfig/cron v1.2.0/go.mod h1:JGuDeoQd7Z6yL4zQhZ3OPEVHB7fL6Ka6skscFHfmt2k=
 github.com/rogpeppe/fastuuid v1.2.0/go.mod h1:jVj6XXZzXRy/MSR5jhDC/2q6DgLz+nrA6LYCDYWNEvQ=
@@ -831,8 +831,9 @@ golang.org/x/net v0.0.0-20221014081412-f15817d10f9b/go.mod h1:YDH+HFinaLZZlnHAfS
 golang.org/x/net v0.2.0/go.mod h1:KqCZLdyyvdV855qA2rE3GC2aiw5xGR5TEjj8smXukLY=
 golang.org/x/net v0.4.0/go.mod h1:MBQ8lrhLObU/6UmLb4fmbmk5OcyYmqtbGd/9yIeKjEE=
 golang.org/x/net v0.5.0/go.mod h1:DivGGAXEgPSlEBzxGzZI+ZLohi+xUj054jfeKui00ws=
-golang.org/x/net v0.6.0 h1:L4ZwwTvKW9gr0ZMS1yrHD9GZhIuVjOBBnaKH+SPQK0Q=
 golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
+golang.org/x/net v0.7.0 h1:rJrUqqhjsgNp7KqAIc25s9pZnjU7TUcSY7HcVZjdn1g=
+golang.org/x/net v0.7.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
diff --git a/internal/protocol.go b/internal/protocol.go
index cb4c041b..a06aa818 100644
--- a/internal/protocol.go
+++ b/internal/protocol.go
@@ -39,6 +39,8 @@ const (
 	signalExternalWorkflowCommand = "SignalExternalWorkflow"
 	cancelExternalWorkflowCommand = "CancelExternalWorkflow"
 
+	undefinedResponse = "UndefinedResponse"
+
 	cancelCommand = "Cancel"
 	panicCommand  = "Panic"
 )
@@ -59,16 +61,12 @@ type Context struct {
 type Message struct {
 	// ID contains ID of the command, response or error.
 	ID uint64 `json:"id"`
-
 	// Command of the message in unmarshalled form. Pointer.
 	Command any `json:"command,omitempty"`
-
 	// Failure associated with command id.
 	Failure *failure.Failure `json:"failure,omitempty"`
-
 	// Payloads contains message specific payloads in binary format.
 	Payloads *commonpb.Payloads `json:"payloads,omitempty"`
-
 	// Header
 	Header *commonpb.Header `json:"header,omitempty"`
 }
@@ -83,6 +81,14 @@ func (msg *Message) IsCommand() bool {
 	return msg.Command != nil
 }
 
+func (msg *Message) UndefinedResponse() bool {
+	if _, ok := msg.Command.(*UndefinedResponse); ok {
+		return true
+	}
+
+	return false
+}
+
 func (msg *Message) Reset() {
 	msg.ID = 0
 	msg.Command = nil
@@ -251,6 +257,11 @@ type CancelExternalWorkflow struct {
 	RunID      string `json:"runID"`
 }
 
+// UndefinedResponse indicates that we should panic the workflow
+type UndefinedResponse struct {
+	Message string `json:"message"`
+}
+
 // Cancel one or multiple internal promises (activities, local activities, timers, child workflows).
 type Cancel struct {
 	// CommandIDs to be canceled.
@@ -471,7 +482,10 @@ func InitCommand(name string) (any, error) {
 	case panicCommand:
 		return &Panic{}, nil
 
+	case undefinedResponse:
+		return &UndefinedResponse{}, nil
+
 	default:
-		return nil, errors.E(op, errors.Errorf("undefined command name: %s", name))
+		return nil, errors.E(op, errors.Errorf("undefined command name: %s, possible outdated RoadRunner version", name))
 	}
 }
diff --git a/proto/api b/proto/api
index e381e518..81ffad23 160000
--- a/proto/api
+++ b/proto/api
@@ -1 +1 @@
-Subproject commit e381e51864ec8f43a90750ef936705258b8f64b2
+Subproject commit 81ffad237fd9805a2216d22559aaf7acdc8ced17
diff --git a/proto/protocol/v1/protocol.pb.go b/proto/protocol/v1/protocol.pb.go
index c7bc7b34..a2495a7b 100644
--- a/proto/protocol/v1/protocol.pb.go
+++ b/proto/protocol/v1/protocol.pb.go
@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
 // 	protoc-gen-go v1.28.1
-// 	protoc        v3.21.10
+// 	protoc        v3.21.12
 // source: protocol/v1/protocol.proto
 
 package protocolV1