diff --git a/go/api/devices_list.go b/go/api/devices_list.go
index ac7fd8c..689613f 100644
--- a/go/api/devices_list.go
+++ b/go/api/devices_list.go
@@ -2,6 +2,7 @@ package api
 
 import (
 	"github.com/tigorlazuardi/bluemage/go/pkg/errs"
+	"github.com/tigorlazuardi/bluemage/go/pkg/telemetry"
 	"golang.org/x/net/context"
 
 	. "github.com/go-jet/jet/v2/sqlite"
@@ -61,7 +62,7 @@ func (request ListDevicesRequest) Statement() SelectStatement {
 
 func (api *API) DevicesList(ctx context.Context, req ListDevicesRequest) (resp []model.Devices, err error) {
 	ctx, span := tracer.Start(ctx, "DevicesList")
-	defer span.End()
+	defer func() { telemetry.EndWithStatus(span, err) }()
 
 	stmt := req.Statement()
 	if err := stmt.QueryContext(ctx, api.DB, &resp); err != nil {
diff --git a/go/api/devices_update.go b/go/api/devices_update.go
index 8733750..7ddef56 100644
--- a/go/api/devices_update.go
+++ b/go/api/devices_update.go
@@ -8,16 +8,21 @@ import (
 	"github.com/tigorlazuardi/bluemage/go/gen/models"
 	"github.com/tigorlazuardi/bluemage/go/pkg/errs"
 	"github.com/tigorlazuardi/bluemage/go/pkg/log"
+	"github.com/tigorlazuardi/bluemage/go/pkg/telemetry"
 )
 
 func (api *API) DevicesUpdate(ctx context.Context, slug string, update *models.DeviceSetter) (err error) {
+	ctx, span := tracer.Start(ctx, "DevicesUpdate")
+	defer func() { telemetry.EndWithStatus(span, err) }()
+
 	exist, err := api.DevicesExist(ctx, slug)
 	if err != nil {
 		return err
 	}
 
 	if !exist {
-		return errs.Failf("device with slug %q does not exist", slug)
+		err = errs.Failf("device with slug %q does not exist", slug)
+		return err
 	}
 
 	ctx, coll := log.WithQueryCollector(ctx)
@@ -30,16 +35,19 @@ func (api *API) DevicesUpdate(ctx context.Context, slug string, update *models.D
 	if err != nil {
 		if sqlite3Err := new(sqlite3.Error); errors.As(err, &sqlite3Err) {
 			if sqlite3Err.Code == sqlite3.ErrConstraint {
-				return errs.
+				err = errs.
 					Wrapw(
 						err, "a device with the same slug already exists",
 						"slug", slug,
 						"update", update,
 						"query", coll,
 					)
+
+				return err
 			}
 		}
-		return errs.Wrapw(err, "failed to update device", "slug", slug, "update", update, "query", coll)
+		err = errs.Wrapw(err, "failed to update device", "slug", slug, "update", update, "query", coll)
+		return err
 	}
 
 	return nil
diff --git a/go/converts/device.go b/go/converts/device.go
index 22136f2..cd8058c 100644
--- a/go/converts/device.go
+++ b/go/converts/device.go
@@ -40,7 +40,7 @@ type DeviceConverter interface {
 	JetModelDeviceToProtoDevice(model.Devices) *device.Device
 
 	// goverter:useZeroValueOnPointerInconsistency
-	ListDevicesRequestToAPIListDevicesRequest(*device.ListDevicesRequest) api.ListDevicesRequest
+	ProtoListDevicesRequestToAPIListDevicesRequest(*device.ListDevicesRequest) api.ListDevicesRequest
 
 	// goverter:ignore Slug SingleFolderMode CreatedAt UpdatedAt
 	// goverter:map Nsfw NSFW
diff --git a/go/server/device_handlers.go b/go/server/device_handlers.go
index b9552b3..ed6ae87 100644
--- a/go/server/device_handlers.go
+++ b/go/server/device_handlers.go
@@ -48,12 +48,14 @@ func (d *DeviceHandler) GetDevice(ctx context.Context, request *connect.Request[
 
 // ListDevices implements v1connect.DeviceServiceHandler.
 func (d *DeviceHandler) ListDevices(ctx context.Context, request *connect.Request[device.ListDevicesRequest]) (*connect.Response[device.ListDevicesResponse], error) {
-	listRequest := deviceConvert.ListDevicesRequestToAPIListDevicesRequest(request.Msg)
+	listRequest := deviceConvert.ProtoListDevicesRequestToAPIListDevicesRequest(request.Msg)
 	devices, err := d.API.DevicesList(ctx, listRequest)
 	if err != nil {
 		return nil, errs.IntoConnectError(err)
 	}
-	resp := &device.ListDevicesResponse{}
+	resp := &device.ListDevicesResponse{
+		Devices: make([]*device.Device, 0, len(devices)),
+	}
 	for _, device := range devices {
 		resp.Devices = append(resp.Devices, deviceConvert.JetModelDeviceToProtoDevice(device))
 	}