diff --git a/common/testing/mocksdk/client_mock.go b/common/testing/mocksdk/client_mock.go
index d9e9d46c0e3..83d786a7997 100644
--- a/common/testing/mocksdk/client_mock.go
+++ b/common/testing/mocksdk/client_mock.go
@@ -100,6 +100,20 @@ func (mr *MockClientMockRecorder) CompleteActivity(ctx, taskToken, result, err a
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CompleteActivity", reflect.TypeOf((*MockClient)(nil).CompleteActivity), ctx, taskToken, result, err)
 }
 
+// CompleteActivityByActivityID mocks base method.
+func (m *MockClient) CompleteActivityByActivityID(ctx context.Context, namespace, activityID, activityRunID string, result any, err error) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "CompleteActivityByActivityID", ctx, namespace, activityID, activityRunID, result, err)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// CompleteActivityByActivityID indicates an expected call of CompleteActivityByActivityID.
+func (mr *MockClientMockRecorder) CompleteActivityByActivityID(ctx, namespace, activityID, activityRunID, result, err any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CompleteActivityByActivityID", reflect.TypeOf((*MockClient)(nil).CompleteActivityByActivityID), ctx, namespace, activityID, activityRunID, result, err)
+}
+
 // CompleteActivityByID mocks base method.
 func (m *MockClient) CompleteActivityByID(ctx context.Context, namespace, workflowID, runID, activityID string, result any, err error) error {
 	m.ctrl.T.Helper()
@@ -114,6 +128,21 @@ func (mr *MockClientMockRecorder) CompleteActivityByID(ctx, namespace, workflowI
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CompleteActivityByID", reflect.TypeOf((*MockClient)(nil).CompleteActivityByID), ctx, namespace, workflowID, runID, activityID, result, err)
 }
 
+// CountActivities mocks base method.
+func (m *MockClient) CountActivities(ctx context.Context, options client.CountActivitiesOptions) (*client.CountActivitiesResult, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "CountActivities", ctx, options)
+	ret0, _ := ret[0].(*client.CountActivitiesResult)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// CountActivities indicates an expected call of CountActivities.
+func (mr *MockClientMockRecorder) CountActivities(ctx, options any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CountActivities", reflect.TypeOf((*MockClient)(nil).CountActivities), ctx, options)
+}
+
 // CountWorkflow mocks base method.
 func (m *MockClient) CountWorkflow(ctx context.Context, request *workflowservice.CountWorkflowExecutionsRequest) (*workflowservice.CountWorkflowExecutionsResponse, error) {
 	m.ctrl.T.Helper()
@@ -203,6 +232,26 @@ func (mr *MockClientMockRecorder) DescribeWorkflowExecution(ctx, workflowID, run
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "DescribeWorkflowExecution", reflect.TypeOf((*MockClient)(nil).DescribeWorkflowExecution), ctx, workflowID, runID)
 }
 
+// ExecuteActivity mocks base method.
+func (m *MockClient) ExecuteActivity(ctx context.Context, options client.StartActivityOptions, activity any, args ...any) (client.ActivityHandle, error) {
+	m.ctrl.T.Helper()
+	varargs := []any{ctx, options, activity}
+	for _, a := range args {
+		varargs = append(varargs, a)
+	}
+	ret := m.ctrl.Call(m, "ExecuteActivity", varargs...)
+	ret0, _ := ret[0].(client.ActivityHandle)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// ExecuteActivity indicates an expected call of ExecuteActivity.
+func (mr *MockClientMockRecorder) ExecuteActivity(ctx, options, activity any, args ...any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	varargs := append([]any{ctx, options, activity}, args...)
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ExecuteActivity", reflect.TypeOf((*MockClient)(nil).ExecuteActivity), varargs...)
+}
+
 // ExecuteWorkflow mocks base method.
 func (m *MockClient) ExecuteWorkflow(ctx context.Context, options client.StartWorkflowOptions, workflow any, args ...any) (client.WorkflowRun, error) {
 	m.ctrl.T.Helper()
@@ -223,6 +272,20 @@ func (mr *MockClientMockRecorder) ExecuteWorkflow(ctx, options, workflow any, ar
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ExecuteWorkflow", reflect.TypeOf((*MockClient)(nil).ExecuteWorkflow), varargs...)
 }
 
+// GetActivityHandle mocks base method.
+func (m *MockClient) GetActivityHandle(options client.GetActivityHandleOptions) client.ActivityHandle {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "GetActivityHandle", options)
+	ret0, _ := ret[0].(client.ActivityHandle)
+	return ret0
+}
+
+// GetActivityHandle indicates an expected call of GetActivityHandle.
+func (mr *MockClientMockRecorder) GetActivityHandle(options any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetActivityHandle", reflect.TypeOf((*MockClient)(nil).GetActivityHandle), options)
+}
+
 // GetSearchAttributes mocks base method.
 func (m *MockClient) GetSearchAttributes(ctx context.Context) (*workflowservice.GetSearchAttributesResponse, error) {
 	m.ctrl.T.Helper()
@@ -325,6 +388,21 @@ func (mr *MockClientMockRecorder) GetWorkflowUpdateHandle(ref any) *gomock.Call
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetWorkflowUpdateHandle", reflect.TypeOf((*MockClient)(nil).GetWorkflowUpdateHandle), ref)
 }
 
+// ListActivities mocks base method.
+func (m *MockClient) ListActivities(ctx context.Context, options client.ListActivitiesOptions) (client.ListActivitiesResult, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "ListActivities", ctx, options)
+	ret0, _ := ret[0].(client.ListActivitiesResult)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// ListActivities indicates an expected call of ListActivities.
+func (mr *MockClientMockRecorder) ListActivities(ctx, options any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ListActivities", reflect.TypeOf((*MockClient)(nil).ListActivities), ctx, options)
+}
+
 // ListArchivedWorkflow mocks base method.
 func (m *MockClient) ListArchivedWorkflow(ctx context.Context, request *workflowservice.ListArchivedWorkflowExecutionsRequest) (*workflowservice.ListArchivedWorkflowExecutionsResponse, error) {
 	m.ctrl.T.Helper()
diff --git a/go.mod b/go.mod
index aa2d4196166..bf8973058ec 100644
--- a/go.mod
+++ b/go.mod
@@ -33,7 +33,7 @@ require (
 	github.com/lib/pq v1.10.9
 	github.com/maruel/panicparse/v2 v2.4.0
 	github.com/mitchellh/mapstructure v1.5.0
-	github.com/nexus-rpc/sdk-go v0.5.2-0.20260211051645-26b0b4c584e5
+	github.com/nexus-rpc/sdk-go v0.6.0
 	github.com/olekukonko/tablewriter v0.0.5
 	github.com/olivere/elastic/v7 v7.0.32
 	github.com/prometheus/client_golang v1.21.0
@@ -60,7 +60,7 @@ require (
 	go.opentelemetry.io/otel/sdk/metric v1.40.0
 	go.opentelemetry.io/otel/trace v1.40.0
 	go.temporal.io/api v1.62.5
-	go.temporal.io/sdk v1.38.0
+	go.temporal.io/sdk v1.41.1
 	go.uber.org/fx v1.24.0
 	go.uber.org/mock v0.6.0
 	go.uber.org/multierr v1.11.0
diff --git a/go.sum b/go.sum
index ab7a7f9f222..5078aac257c 100644
--- a/go.sum
+++ b/go.sum
@@ -238,8 +238,8 @@ github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq
 github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ=
 github.com/ncruces/go-strftime v1.0.0 h1:HMFp8mLCTPp341M/ZnA4qaf7ZlsbTc+miZjCLOFAw7w=
 github.com/ncruces/go-strftime v1.0.0/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
-github.com/nexus-rpc/sdk-go v0.5.2-0.20260211051645-26b0b4c584e5 h1:Van9KGGs8lcDgxzSNFbDhEMNeJ80TbBxwZ45f9iBk9U=
-github.com/nexus-rpc/sdk-go v0.5.2-0.20260211051645-26b0b4c584e5/go.mod h1:FHdPfVQwRuJFZFTF0Y2GOAxCrbIBNrcPna9slkGKPYk=
+github.com/nexus-rpc/sdk-go v0.6.0 h1:QRgnP2zTbxEbiyWG/aXH8uSC5LV/Mg1fqb19jb4DBlo=
+github.com/nexus-rpc/sdk-go v0.6.0/go.mod h1:FHdPfVQwRuJFZFTF0Y2GOAxCrbIBNrcPna9slkGKPYk=
 github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e/go.mod h1:zD1mROLANZcx1PVRCS0qkT7pwLkGfwJo4zjcN/Tysno=
 github.com/olekukonko/tablewriter v0.0.5 h1:P2Ga83D34wi1o9J6Wh1mRuqd4mF/x/lgBS7N7AbDhec=
 github.com/olekukonko/tablewriter v0.0.5/go.mod h1:hPp6KlRPjbx+hW8ykQs1w3UBbZlj6HuIJcUGPhkA7kY=
@@ -378,8 +378,8 @@ go.opentelemetry.io/proto/otlp v1.7.1 h1:gTOMpGDb0WTBOP8JaO72iL3auEZhVmAQg4ipjOV
 go.opentelemetry.io/proto/otlp v1.7.1/go.mod h1:b2rVh6rfI/s2pHWNlB7ILJcRALpcNDzKhACevjI+ZnE=
 go.temporal.io/api v1.62.5 h1:9R/9CeyM7xqHSlsNt+QIvapQLcRxCZ38bnXQx4mCN6I=
 go.temporal.io/api v1.62.5/go.mod h1:iaxoP/9OXMJcQkETTECfwYq4cw/bj4nwov8b3ZLVnXM=
-go.temporal.io/sdk v1.38.0 h1:4Bok5LEdED7YKpsSjIa3dDqram5VOq+ydBf4pyx0Wo4=
-go.temporal.io/sdk v1.38.0/go.mod h1:a+R2Ej28ObvHoILbHaxMyind7M6D+W0L7edt5UJF4SE=
+go.temporal.io/sdk v1.41.1 h1:yOpvsHyDD1lNuwlGBv/SUodCPhjv9nDeC9lLHW/fJUA=
+go.temporal.io/sdk v1.41.1/go.mod h1:/InXQT5guZ6AizYzpmzr5avQ/GMgq1ZObcKlKE2AhTc=
 go.uber.org/atomic v1.5.0/go.mod h1:sABNBOSYdrvTF6hTgEIbc7YasKWGhgEQZyfxyTvoXHQ=
 go.uber.org/atomic v1.7.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
 go.uber.org/atomic v1.11.0 h1:ZvwS0R+56ePWxUNi+Atn9dWONBPp/AUETXlHW0DxSjE=
diff --git a/tests/nexus_workflow_test.go b/tests/nexus_workflow_test.go
index 93ce8b1cd74..4acf8dd67fc 100644
--- a/tests/nexus_workflow_test.go
+++ b/tests/nexus_workflow_test.go
@@ -69,7 +69,7 @@ func (s *NexusWorkflowTestSuite) TestNexusOperationCancelation() {
 	h := nexustest.Handler{
 		OnStartOperation: func(ctx context.Context, service, operation string, input *nexus.LazyValue, options nexus.StartOperationOptions) (nexus.HandlerStartOperationResult[any], error) {
 			if service != "service" {
-				return nil, nexus.HandlerErrorf(nexus.HandlerErrorTypeBadRequest, `expected service to equal "service"`)
+				return nil, nexus.NewHandlerErrorf(nexus.HandlerErrorTypeBadRequest, `expected service to equal "service"`)
 			}
 			return &nexus.HandlerStartOperationResultAsync{OperationToken: "test"}, nil
 		},
@@ -77,7 +77,7 @@ func (s *NexusWorkflowTestSuite) TestNexusOperationCancelation() {
 			if !firstCancelSeen {
 				// Fail cancel request once to test NexusOperationCancelRequestFailed event is recorded and request is retried.
 				firstCancelSeen = true
-				return nexus.HandlerErrorf(nexus.HandlerErrorTypeBadRequest, "intentional non-retyrable cancel error for test")
+				return nexus.NewHandlerErrorf(nexus.HandlerErrorTypeBadRequest, "intentional non-retyrable cancel error for test")
 			}
 			return nil
 		},
@@ -2057,17 +2057,17 @@ func (s *NexusWorkflowTestSuite) TestNexusSyncOperationErrorRehydration() {
 	op := nexus.NewSyncOperation("op", func(ctx context.Context, outcome string, soo nexus.StartOperationOptions) (nexus.NoValue, error) {
 		switch outcome {
 		case "fail-handler-internal":
-			return nil, nexus.HandlerErrorf(nexus.HandlerErrorTypeInternal, "intentional internal error")
+			return nil, nexus.NewHandlerErrorf(nexus.HandlerErrorTypeInternal, "intentional internal error")
 		case "fail-handler-app-error":
 			return nil, temporal.NewApplicationError("app error", "TestError", "details")
 		case "fail-handler-bad-request":
-			return nil, nexus.HandlerErrorf(nexus.HandlerErrorTypeBadRequest, "bad request")
+			return nil, nexus.NewHandlerErrorf(nexus.HandlerErrorTypeBadRequest, "bad request")
 		case "fail-operation":
-			return nil, nexus.NewOperationFailedError("some error")
+			return nil, nexus.NewOperationFailedErrorf("some error")
 		case "fail-operation-app-error":
 			return nil, temporal.NewNonRetryableApplicationError("app error", "TestError", nil, "details")
 		}
-		return nil, nexus.HandlerErrorf(nexus.HandlerErrorTypeBadRequest, "unexpected outcome: %s", outcome)
+		return nil, nexus.NewHandlerErrorf(nexus.HandlerErrorTypeBadRequest, "unexpected outcome: %s", outcome)
 	})
 	s.NoError(svc.Register(op))
 
@@ -2095,9 +2095,7 @@ func (s *NexusWorkflowTestSuite) TestNexusSyncOperationErrorRehydration() {
 				var handlerErr *nexus.HandlerError
 				require.ErrorAs(t, pendingErr, &handlerErr)
 				require.Equal(t, nexus.HandlerErrorTypeInternal, handlerErr.Type)
-				var appErr *temporal.ApplicationError
-				require.ErrorAs(t, handlerErr.Cause, &appErr)
-				require.Equal(t, "intentional internal error", appErr.Message())
+				require.Equal(t, "intentional internal error", handlerErr.Message)
 			},
 		},
 		{
@@ -2125,9 +2123,7 @@ func (s *NexusWorkflowTestSuite) TestNexusSyncOperationErrorRehydration() {
 				var handlerErr *nexus.HandlerError
 				require.ErrorAs(t, opErr, &handlerErr)
 				require.Equal(t, nexus.HandlerErrorTypeBadRequest, handlerErr.Type)
-				var appErr *temporal.ApplicationError
-				require.ErrorAs(t, handlerErr.Cause, &appErr)
-				require.Equal(t, "bad request", appErr.Message())
+				require.Equal(t, "bad request", handlerErr.Message)
 			},
 		},
 		{