diff --git a/pkg/mcp/tools_layout.go b/pkg/mcp/tools_layout.go
index 1719ce5..be2f3f9 100644
--- a/pkg/mcp/tools_layout.go
+++ b/pkg/mcp/tools_layout.go
@@ -182,7 +182,7 @@ func (s *Subsystem) registerLayoutTools(server *mcp.Server) {
 	mcp.AddTool(server, &mcp.Tool{Name: "layout_delete", Description: "Delete a saved layout"}, s.layoutDelete)
 	mcp.AddTool(server, &mcp.Tool{Name: "layout_get", Description: "Get a specific layout by name"}, s.layoutGet)
 	mcp.AddTool(server, &mcp.Tool{Name: "layout_tile", Description: "Tile windows in a grid arrangement"}, s.layoutTile)
-	mcp.AddTool(server, &mcp.Tool{Name: "layout_snap", Description: "Snap a window to a screen edge or corner"}, s.layoutSnap)
+	mcp.AddTool(server, &mcp.Tool{Name: "layout_snap", Description: "Snap a window to a screen edge, corner, or center"}, s.layoutSnap)
 	mcp.AddTool(server, &mcp.Tool{Name: "layout_stack", Description: "Stack windows in a cascade pattern"}, s.layoutStack)
 	mcp.AddTool(server, &mcp.Tool{Name: "layout_workflow", Description: "Apply a preset workflow layout"}, s.layoutWorkflow)
 }
diff --git a/pkg/window/service.go b/pkg/window/service.go
index be5bce5..a72d18f 100644
--- a/pkg/window/service.go
+++ b/pkg/window/service.go
@@ -244,13 +244,7 @@ func (s *Service) trackWindow(platformWindow PlatformWindow) {
 		case "resize":
 			if data := event.Data; data != nil {
 				width, _ := data["width"].(int)
-				if width == 0 {
-					width, _ = data["w"].(int)
-				}
 				height, _ := data["height"].(int)
-				if height == 0 {
-					height, _ = data["h"].(int)
-				}
 				_ = s.Core().ACTION(ActionWindowResized{Name: event.Name, Width: width, Height: height})
 			}
 		case "close":
@@ -452,7 +446,7 @@ var snapPosMap = map[string]SnapPosition{
 	"top": SnapTop, "bottom": SnapBottom,
 	"top-left": SnapTopLeft, "top-right": SnapTopRight,
 	"bottom-left": SnapBottomLeft, "bottom-right": SnapBottomRight,
-	"center": SnapCenter, "centre": SnapCenter,
+	"center": SnapCenter,
 }
 
 func (s *Service) taskSnapWindow(name, position string) error {
diff --git a/pkg/window/service_screen_test.go b/pkg/window/service_screen_test.go
index 98f283d..4dee1f8 100644
--- a/pkg/window/service_screen_test.go
+++ b/pkg/window/service_screen_test.go
@@ -99,6 +99,48 @@ func TestTaskSnapWindow_UsesPrimaryScreenSize(t *testing.T) {
 	assert.Equal(t, 1000, info.Height)
 }
 
+func TestTaskSnapWindow_Center_Good(t *testing.T) {
+	_, c := newTestWindowServiceWithScreen(t, []screen.Screen{
+		{
+			ID: "1", Name: "Primary", IsPrimary: true,
+			Bounds:   screen.Rect{X: 0, Y: 0, Width: 2000, Height: 1000},
+			WorkArea: screen.Rect{X: 0, Y: 0, Width: 2000, Height: 1000},
+		},
+	})
+
+	_, _, err := c.PERFORM(TaskOpenWindow{Window: Window{Name: "snap", Width: 400, Height: 300}})
+	require.NoError(t, err)
+
+	_, handled, err := c.PERFORM(TaskSnapWindow{Name: "snap", Position: "center"})
+	require.NoError(t, err)
+	assert.True(t, handled)
+
+	result, _, err := c.QUERY(QueryWindowByName{Name: "snap"})
+	require.NoError(t, err)
+	info := result.(*WindowInfo)
+	assert.Equal(t, 800, info.X)
+	assert.Equal(t, 350, info.Y)
+	assert.Equal(t, 400, info.Width)
+	assert.Equal(t, 300, info.Height)
+}
+
+func TestTaskSnapWindow_LegacyCentre_Bad(t *testing.T) {
+	_, c := newTestWindowServiceWithScreen(t, []screen.Screen{
+		{
+			ID: "1", Name: "Primary", IsPrimary: true,
+			Bounds:   screen.Rect{X: 0, Y: 0, Width: 2000, Height: 1000},
+			WorkArea: screen.Rect{X: 0, Y: 0, Width: 2000, Height: 1000},
+		},
+	})
+
+	_, _, err := c.PERFORM(TaskOpenWindow{Window: Window{Name: "snap", Width: 400, Height: 300}})
+	require.NoError(t, err)
+
+	_, handled, err := c.PERFORM(TaskSnapWindow{Name: "snap", Position: "centre"})
+	assert.True(t, handled)
+	assert.Error(t, err)
+}
+
 func TestTaskTileWindows_UsesPrimaryWorkAreaOrigin(t *testing.T) {
 	_, c := newTestWindowServiceWithScreen(t, []screen.Screen{
 		{
diff --git a/pkg/window/service_test.go b/pkg/window/service_test.go
index db25a22..b36b530 100644
--- a/pkg/window/service_test.go
+++ b/pkg/window/service_test.go
@@ -226,6 +226,52 @@ func TestFileDrop_Good(t *testing.T) {
 	mu.Unlock()
 }
 
+func TestWindowResizeEvent_UsesCanonicalPayload_Good(t *testing.T) {
+	svc, c := newTestWindowService(t)
+
+	_, _, _ = c.PERFORM(TaskOpenWindow{Window: Window{Name: "resize-test"}})
+
+	var (
+		resized ActionWindowResized
+		seen    bool
+	)
+	c.RegisterAction(func(_ *core.Core, msg core.Message) error {
+		if a, ok := msg.(ActionWindowResized); ok {
+			resized = a
+			seen = true
+		}
+		return nil
+	})
+
+	pw, ok := svc.Manager().Get("resize-test")
+	require.True(t, ok)
+	mw := pw.(*mockWindow)
+
+	mw.emit(WindowEvent{
+		Type: "resize",
+		Name: "resize-test",
+		Data: map[string]any{"width": 111, "height": 222},
+	})
+
+	assert.True(t, seen)
+	assert.Equal(t, "resize-test", resized.Name)
+	assert.Equal(t, 111, resized.Width)
+	assert.Equal(t, 222, resized.Height)
+
+	resized = ActionWindowResized{}
+	seen = false
+	mw.emit(WindowEvent{
+		Type: "resize",
+		Name: "resize-test",
+		Data: map[string]any{"w": 333, "h": 444},
+	})
+
+	assert.True(t, seen)
+	assert.Equal(t, "resize-test", resized.Name)
+	assert.Equal(t, 0, resized.Width)
+	assert.Equal(t, 0, resized.Height)
+}
+
 // --- TaskMinimize ---
 
 func TestTaskMinimize_Good(t *testing.T) {
diff --git a/pkg/window/tiling.go b/pkg/window/tiling.go
index 9e3a3e2..28a073b 100644
--- a/pkg/window/tiling.go
+++ b/pkg/window/tiling.go
@@ -180,7 +180,7 @@ func (m *Manager) TileWindows(mode TileMode, names []string, screenW, screenH in
 	return nil
 }
 
-// SnapWindow snaps a window to a screen edge/corner/centre.
+// SnapWindow snaps a window to a screen edge, corner, or center.
 func (m *Manager) SnapWindow(name string, pos SnapPosition, screenW, screenH int, origin ...int) error {
 	originX, originY := layoutOrigin(origin)
 	pw, ok := m.Get(name)