diff --git a/src/components/__tests__/FloatingActionBar.test.tsx b/src/components/__tests__/FloatingActionBar.test.tsx
new file mode 100644
index 00000000..06882aaf
--- /dev/null
+++ b/src/components/__tests__/FloatingActionBar.test.tsx
@@ -0,0 +1,777 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { render, screen, fireEvent, waitFor } from "@testing-library/react";
+import { FloatingActionBar } from "@/components/FloatingActionBar";
+import { ReactFlowProvider } from "@xyflow/react";
+import { ProviderSettings } from "@/types";
+
+// Mock the workflow store
+const mockAddNode = vi.fn();
+const mockExecuteWorkflow = vi.fn();
+const mockRegenerateNode = vi.fn();
+const mockStopWorkflow = vi.fn();
+const mockValidateWorkflow = vi.fn();
+const mockSetEdgeStyle = vi.fn();
+const mockSetModelSearchOpen = vi.fn();
+const mockUseWorkflowStore = vi.fn();
+
+vi.mock("@/store/workflowStore", () => ({
+  useWorkflowStore: (selector?: (state: unknown) => unknown) => {
+    if (selector) {
+      return mockUseWorkflowStore(selector);
+    }
+    return mockUseWorkflowStore((s: unknown) => s);
+  },
+}));
+
+// Mock useReactFlow
+const mockScreenToFlowPosition = vi.fn((pos) => pos);
+const mockGetNodes = vi.fn(() => []);
+
+vi.mock("@xyflow/react", async () => {
+  const actual = await vi.importActual("@xyflow/react");
+  return {
+    ...actual,
+    useReactFlow: () => ({
+      screenToFlowPosition: mockScreenToFlowPosition,
+      getNodes: mockGetNodes,
+    }),
+  };
+});
+
+// Mock ModelSearchDialog
+vi.mock("@/components/modals/ModelSearchDialog", () => ({
+  ModelSearchDialog: ({ isOpen, onClose, initialProvider }: { isOpen: boolean; onClose: () => void; initialProvider?: string }) => (
+    isOpen ? (
+      <div data-testid="model-search-dialog" data-provider={initialProvider}>
+        Model Search Dialog
+        <button onClick={onClose}>Close</button>
+      </div>
+    ) : null
+  ),
+}));
+
+// Mock fetch for env-status
+const mockFetch = vi.fn();
+global.fetch = mockFetch;
+
+// Wrapper component for React Flow context
+function TestWrapper({ children }: { children: React.ReactNode }) {
+  return <ReactFlowProvider>{children}</ReactFlowProvider>;
+}
+
+// Default provider settings
+const defaultProviderSettings: ProviderSettings = {
+  providers: {
+    gemini: { id: "gemini", name: "Gemini", enabled: true, apiKey: null, apiKeyEnvVar: "GEMINI_API_KEY" },
+    openai: { id: "openai", name: "OpenAI", enabled: false, apiKey: null },
+    replicate: { id: "replicate", name: "Replicate", enabled: false, apiKey: null },
+    fal: { id: "fal", name: "fal.ai", enabled: true, apiKey: null },
+  },
+};
+
+// Default store state factory
+const createDefaultState = (overrides = {}) => ({
+  nodes: [],
+  isRunning: false,
+  executeWorkflow: mockExecuteWorkflow,
+  regenerateNode: mockRegenerateNode,
+  stopWorkflow: mockStopWorkflow,
+  validateWorkflow: mockValidateWorkflow,
+  edgeStyle: "angular" as const,
+  setEdgeStyle: mockSetEdgeStyle,
+  providerSettings: defaultProviderSettings,
+  setModelSearchOpen: mockSetModelSearchOpen,
+  modelSearchOpen: false,
+  modelSearchProvider: null,
+  addNode: mockAddNode,
+  ...overrides,
+});
+
+describe("FloatingActionBar", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockValidateWorkflow.mockReturnValue({ valid: true, errors: [] });
+    mockFetch.mockResolvedValue({
+      ok: true,
+      json: () => Promise.resolve({ gemini: true, openai: false, replicate: false }),
+    });
+
+    // Default mock implementation
+    mockUseWorkflowStore.mockImplementation((selector) => {
+      return selector(createDefaultState());
+    });
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  describe("Basic Rendering", () => {
+    it("should render node type buttons", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Image")).toBeInTheDocument();
+        expect(screen.getByText("Annotate")).toBeInTheDocument();
+        expect(screen.getByText("Prompt")).toBeInTheDocument();
+        expect(screen.getByText("Output")).toBeInTheDocument();
+      });
+    });
+
+    it("should render Generate combo button", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Generate")).toBeInTheDocument();
+      });
+    });
+
+    it("should render Run button", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Run")).toBeInTheDocument();
+      });
+    });
+
+    it("should render edge style toggle button", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Switch to curved connectors")).toBeInTheDocument();
+      });
+    });
+  });
+
+  describe("Node Button Click", () => {
+    it("should call addNode when Image button is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Image")).toBeInTheDocument();
+      });
+
+      const imageButton = screen.getByText("Image");
+      fireEvent.click(imageButton);
+
+      expect(mockAddNode).toHaveBeenCalledWith("imageInput", expect.any(Object));
+    });
+
+    it("should call addNode when Annotate button is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Annotate")).toBeInTheDocument();
+      });
+
+      const annotateButton = screen.getByText("Annotate");
+      fireEvent.click(annotateButton);
+
+      expect(mockAddNode).toHaveBeenCalledWith("annotation", expect.any(Object));
+    });
+
+    it("should call addNode when Prompt button is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Prompt")).toBeInTheDocument();
+      });
+
+      const promptButton = screen.getByText("Prompt");
+      fireEvent.click(promptButton);
+
+      expect(mockAddNode).toHaveBeenCalledWith("prompt", expect.any(Object));
+    });
+
+    it("should call addNode when Output button is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Output")).toBeInTheDocument();
+      });
+
+      const outputButton = screen.getByText("Output");
+      fireEvent.click(outputButton);
+
+      expect(mockAddNode).toHaveBeenCalledWith("output", expect.any(Object));
+    });
+  });
+
+  describe("Node Button Drag", () => {
+    it("should set dataTransfer with node type on drag start", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Image")).toBeInTheDocument();
+      });
+
+      const imageButton = screen.getByText("Image");
+
+      const mockDataTransfer = {
+        setData: vi.fn(),
+        effectAllowed: "",
+      };
+
+      fireEvent.dragStart(imageButton, {
+        dataTransfer: mockDataTransfer,
+      });
+
+      expect(mockDataTransfer.setData).toHaveBeenCalledWith("application/node-type", "imageInput");
+      expect(mockDataTransfer.effectAllowed).toBe("copy");
+    });
+
+    it("should set dataTransfer with prompt type on drag", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Prompt")).toBeInTheDocument();
+      });
+
+      const promptButton = screen.getByText("Prompt");
+
+      const mockDataTransfer = {
+        setData: vi.fn(),
+        effectAllowed: "",
+      };
+
+      fireEvent.dragStart(promptButton, {
+        dataTransfer: mockDataTransfer,
+      });
+
+      expect(mockDataTransfer.setData).toHaveBeenCalledWith("application/node-type", "prompt");
+    });
+  });
+
+  describe("Generate Combo Button", () => {
+    it("should open dropdown menu when Generate button is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Generate")).toBeInTheDocument();
+      });
+
+      const generateButton = screen.getByText("Generate");
+      fireEvent.click(generateButton);
+
+      // Dropdown menu items should appear
+      expect(screen.getByText("Image", { selector: "button.w-full" })).toBeInTheDocument();
+      expect(screen.getByText("Video")).toBeInTheDocument();
+      expect(screen.getByText("Text (LLM)")).toBeInTheDocument();
+    });
+
+    it("should add nanoBanana node when Image option is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Generate")).toBeInTheDocument();
+      });
+
+      // Open dropdown
+      fireEvent.click(screen.getByText("Generate"));
+
+      // Click Image option in dropdown
+      const imageOption = screen.getByText("Image", { selector: "button.w-full" });
+      fireEvent.click(imageOption);
+
+      expect(mockAddNode).toHaveBeenCalledWith("nanoBanana", expect.any(Object));
+    });
+
+    it("should add generateVideo node when Video option is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Generate")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByText("Generate"));
+      fireEvent.click(screen.getByText("Video"));
+
+      expect(mockAddNode).toHaveBeenCalledWith("generateVideo", expect.any(Object));
+    });
+
+    it("should add llmGenerate node when Text (LLM) option is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Generate")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByText("Generate"));
+      fireEvent.click(screen.getByText("Text (LLM)"));
+
+      expect(mockAddNode).toHaveBeenCalledWith("llmGenerate", expect.any(Object));
+    });
+
+    it("should close dropdown after selecting an option", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Generate")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByText("Generate"));
+
+      // Verify dropdown is open
+      expect(screen.getByText("Video")).toBeInTheDocument();
+
+      // Click an option
+      fireEvent.click(screen.getByText("Video"));
+
+      // Dropdown should close
+      expect(screen.queryByText("Video")).not.toBeInTheDocument();
+    });
+  });
+
+  describe("Provider Icon Buttons", () => {
+    it("should render fal.ai icon button (always visible)", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Browse fal.ai models")).toBeInTheDocument();
+      });
+    });
+
+    it("should render Replicate icon when API key is configured", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          providerSettings: {
+            providers: {
+              ...defaultProviderSettings.providers,
+              replicate: { id: "replicate", name: "Replicate", enabled: true, apiKey: "test-key" },
+            },
+          },
+        }));
+      });
+
+      mockFetch.mockResolvedValue({
+        ok: true,
+        json: () => Promise.resolve({ gemini: true, openai: false, replicate: true }),
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Browse Replicate models")).toBeInTheDocument();
+      });
+    });
+
+    it("should open ModelSearchDialog with fal provider when fal.ai icon is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Browse fal.ai models")).toBeInTheDocument();
+      });
+
+      const falButton = screen.getByTitle("Browse fal.ai models");
+      fireEvent.click(falButton);
+
+      expect(mockSetModelSearchOpen).toHaveBeenCalledWith(true, "fal");
+    });
+
+    it("should open ModelSearchDialog with replicate provider when Replicate icon is clicked", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          providerSettings: {
+            providers: {
+              ...defaultProviderSettings.providers,
+              replicate: { id: "replicate", name: "Replicate", enabled: true, apiKey: "test-key" },
+            },
+          },
+        }));
+      });
+
+      mockFetch.mockResolvedValue({
+        ok: true,
+        json: () => Promise.resolve({ gemini: true, openai: false, replicate: true }),
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Browse Replicate models")).toBeInTheDocument();
+      });
+
+      const replicateButton = screen.getByTitle("Browse Replicate models");
+      fireEvent.click(replicateButton);
+
+      expect(mockSetModelSearchOpen).toHaveBeenCalledWith(true, "replicate");
+    });
+  });
+
+  describe("Edge Style Toggle", () => {
+    it("should call setEdgeStyle with curved when currently angular", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Switch to curved connectors")).toBeInTheDocument();
+      });
+
+      const toggleButton = screen.getByTitle("Switch to curved connectors");
+      fireEvent.click(toggleButton);
+
+      expect(mockSetEdgeStyle).toHaveBeenCalledWith("curved");
+    });
+
+    it("should call setEdgeStyle with angular when currently curved", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          edgeStyle: "curved",
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Switch to angular connectors")).toBeInTheDocument();
+      });
+
+      const toggleButton = screen.getByTitle("Switch to angular connectors");
+      fireEvent.click(toggleButton);
+
+      expect(mockSetEdgeStyle).toHaveBeenCalledWith("angular");
+    });
+  });
+
+  describe("Run Button", () => {
+    it("should call executeWorkflow when Run button is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Run")).toBeInTheDocument();
+      });
+
+      const runButton = screen.getByText("Run");
+      fireEvent.click(runButton);
+
+      expect(mockExecuteWorkflow).toHaveBeenCalled();
+    });
+
+    it("should show Stop button when isRunning is true", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          isRunning: true,
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Stop")).toBeInTheDocument();
+      });
+    });
+
+    it("should call stopWorkflow when Stop button is clicked", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          isRunning: true,
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Stop")).toBeInTheDocument();
+      });
+
+      const stopButton = screen.getByText("Stop");
+      fireEvent.click(stopButton);
+
+      expect(mockStopWorkflow).toHaveBeenCalled();
+    });
+
+    it("should disable Run button when workflow is invalid", async () => {
+      mockValidateWorkflow.mockReturnValue({ valid: false, errors: ["No nodes"] });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByText("Run")).toBeInTheDocument();
+      });
+
+      const runButton = screen.getByText("Run").closest("button");
+      expect(runButton).toBeDisabled();
+    });
+
+    it("should show error message in title when workflow is invalid", async () => {
+      mockValidateWorkflow.mockReturnValue({ valid: false, errors: ["Missing required nodes"] });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        const runButton = screen.getByText("Run").closest("button");
+        expect(runButton).toHaveAttribute("title", "Missing required nodes");
+      });
+    });
+  });
+
+  describe("Run Menu Dropdown", () => {
+    it("should show dropdown chevron when workflow is valid and not running", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Run options")).toBeInTheDocument();
+      });
+    });
+
+    it("should not show dropdown chevron when workflow is invalid", async () => {
+      mockValidateWorkflow.mockReturnValue({ valid: false, errors: ["No nodes"] });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.queryByTitle("Run options")).not.toBeInTheDocument();
+      });
+    });
+
+    it("should not show dropdown chevron when running", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          isRunning: true,
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.queryByTitle("Run options")).not.toBeInTheDocument();
+      });
+    });
+
+    it("should open run menu when dropdown chevron is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Run options")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByTitle("Run options"));
+
+      expect(screen.getByText("Run entire workflow")).toBeInTheDocument();
+      expect(screen.getByText("Run from selected node")).toBeInTheDocument();
+      expect(screen.getByText("Run selected node only")).toBeInTheDocument();
+    });
+
+    it("should call executeWorkflow when 'Run entire workflow' is clicked", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Run options")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByTitle("Run options"));
+      fireEvent.click(screen.getByText("Run entire workflow"));
+
+      expect(mockExecuteWorkflow).toHaveBeenCalled();
+    });
+
+    it("should disable 'Run from selected node' when no node is selected", async () => {
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Run options")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByTitle("Run options"));
+
+      const runFromSelectedButton = screen.getByText("Run from selected node").closest("button");
+      expect(runFromSelectedButton).toHaveClass("cursor-not-allowed");
+    });
+
+    it("should enable 'Run from selected node' when a single node is selected", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [{ id: "node-1", selected: true, type: "prompt" }],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Run options")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByTitle("Run options"));
+
+      const runFromSelectedButton = screen.getByText("Run from selected node").closest("button");
+      expect(runFromSelectedButton).not.toHaveClass("cursor-not-allowed");
+    });
+
+    it("should call executeWorkflow with node id when 'Run from selected node' is clicked", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [{ id: "node-1", selected: true, type: "prompt" }],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Run options")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByTitle("Run options"));
+      fireEvent.click(screen.getByText("Run from selected node"));
+
+      expect(mockExecuteWorkflow).toHaveBeenCalledWith("node-1");
+    });
+
+    it("should call regenerateNode when 'Run selected node only' is clicked", async () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [{ id: "node-1", selected: true, type: "prompt" }],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <FloatingActionBar />
+        </TestWrapper>
+      );
+
+      await waitFor(() => {
+        expect(screen.getByTitle("Run options")).toBeInTheDocument();
+      });
+
+      fireEvent.click(screen.getByTitle("Run options"));
+      fireEvent.click(screen.getByText("Run selected node only"));
+
+      expect(mockRegenerateNode).toHaveBeenCalledWith("node-1");
+    });
+  });
+});
diff --git a/src/components/__tests__/MultiSelectToolbar.test.tsx b/src/components/__tests__/MultiSelectToolbar.test.tsx
new file mode 100644
index 00000000..f14273c0
--- /dev/null
+++ b/src/components/__tests__/MultiSelectToolbar.test.tsx
@@ -0,0 +1,538 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen, fireEvent } from "@testing-library/react";
+import { MultiSelectToolbar } from "@/components/MultiSelectToolbar";
+import { ReactFlowProvider } from "@xyflow/react";
+
+// Mock JSZip
+vi.mock("jszip", () => ({
+  default: vi.fn().mockImplementation(() => ({
+    file: vi.fn(),
+    generateAsync: vi.fn().mockResolvedValue(new Blob()),
+  })),
+}));
+
+// Mock the workflow store
+const mockOnNodesChange = vi.fn();
+const mockCreateGroup = vi.fn();
+const mockRemoveNodesFromGroup = vi.fn();
+const mockUseWorkflowStore = vi.fn();
+
+vi.mock("@/store/workflowStore", () => ({
+  useWorkflowStore: (selector?: (state: unknown) => unknown) => {
+    if (selector) {
+      return mockUseWorkflowStore(selector);
+    }
+    return mockUseWorkflowStore((s: unknown) => s);
+  },
+}));
+
+// Mock useReactFlow
+const mockGetViewport = vi.fn(() => ({ x: 0, y: 0, zoom: 1 }));
+
+vi.mock("@xyflow/react", async () => {
+  const actual = await vi.importActual("@xyflow/react");
+  return {
+    ...actual,
+    useReactFlow: () => ({
+      getViewport: mockGetViewport,
+    }),
+  };
+});
+
+// Wrapper component for React Flow context
+function TestWrapper({ children }: { children: React.ReactNode }) {
+  return <ReactFlowProvider>{children}</ReactFlowProvider>;
+}
+
+// Create mock nodes for testing
+const createMockNode = (id: string, overrides = {}) => ({
+  id,
+  type: "prompt",
+  position: { x: 100, y: 100 },
+  data: {},
+  selected: true,
+  measured: { width: 220, height: 200 },
+  ...overrides,
+});
+
+// Default store state factory
+const createDefaultState = (overrides = {}) => ({
+  nodes: [],
+  onNodesChange: mockOnNodesChange,
+  createGroup: mockCreateGroup,
+  removeNodesFromGroup: mockRemoveNodesFromGroup,
+  ...overrides,
+});
+
+describe("MultiSelectToolbar", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    // Default mock implementation - no nodes selected
+    mockUseWorkflowStore.mockImplementation((selector) => {
+      return selector(createDefaultState());
+    });
+  });
+
+  describe("Visibility", () => {
+    it("should not render when no nodes are selected", () => {
+      const { container } = render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(container.firstChild).toBeNull();
+    });
+
+    it("should not render when only one node is selected", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [createMockNode("node-1")],
+        }));
+      });
+
+      const { container } = render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(container.firstChild).toBeNull();
+    });
+
+    it("should render when two or more nodes are selected", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 } }),
+            createMockNode("node-2", { position: { x: 300, y: 0 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Stack horizontally (H)")).toBeInTheDocument();
+    });
+
+    it("should not render when nodes are selected but less than 2", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1"),
+            createMockNode("node-2", { selected: false }),
+          ],
+        }));
+      });
+
+      const { container } = render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(container.firstChild).toBeNull();
+    });
+  });
+
+  describe("Basic Rendering", () => {
+    beforeEach(() => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 } }),
+            createMockNode("node-2", { position: { x: 300, y: 0 } }),
+          ],
+        }));
+      });
+    });
+
+    it("should render stack horizontally button", () => {
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Stack horizontally (H)")).toBeInTheDocument();
+    });
+
+    it("should render stack vertically button", () => {
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Stack vertically (V)")).toBeInTheDocument();
+    });
+
+    it("should render arrange as grid button", () => {
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Arrange as grid (G)")).toBeInTheDocument();
+    });
+
+    it("should render create group button when nodes are not in a group", () => {
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Create group")).toBeInTheDocument();
+    });
+
+    it("should render download images button", () => {
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Download images as ZIP")).toBeInTheDocument();
+    });
+  });
+
+  describe("Stack Horizontally", () => {
+    it("should call onNodesChange when stack horizontally button is clicked", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 50 } }),
+            createMockNode("node-2", { position: { x: 300, y: 0 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const stackHorizontalButton = screen.getByTitle("Stack horizontally (H)");
+      fireEvent.click(stackHorizontalButton);
+
+      // Should be called for each node
+      expect(mockOnNodesChange).toHaveBeenCalled();
+    });
+
+    it("should position nodes from left to right based on their original x position", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 500, y: 100 } }),
+            createMockNode("node-2", { position: { x: 100, y: 50 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      fireEvent.click(screen.getByTitle("Stack horizontally (H)"));
+
+      // First call should position node-2 (at x=100, so it comes first)
+      expect(mockOnNodesChange).toHaveBeenCalledWith([
+        expect.objectContaining({
+          type: "position",
+          id: "node-2",
+          position: expect.objectContaining({ y: 50 }), // Aligned to topmost y
+        }),
+      ]);
+    });
+  });
+
+  describe("Stack Vertically", () => {
+    it("should call onNodesChange when stack vertically button is clicked", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 50, y: 0 } }),
+            createMockNode("node-2", { position: { x: 0, y: 300 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const stackVerticalButton = screen.getByTitle("Stack vertically (V)");
+      fireEvent.click(stackVerticalButton);
+
+      expect(mockOnNodesChange).toHaveBeenCalled();
+    });
+
+    it("should position nodes from top to bottom based on their original y position", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 100, y: 500 } }),
+            createMockNode("node-2", { position: { x: 50, y: 100 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      fireEvent.click(screen.getByTitle("Stack vertically (V)"));
+
+      // First call should position node-2 (at y=100, so it comes first)
+      expect(mockOnNodesChange).toHaveBeenCalledWith([
+        expect.objectContaining({
+          type: "position",
+          id: "node-2",
+          position: expect.objectContaining({ x: 50 }), // Aligned to leftmost x
+        }),
+      ]);
+    });
+  });
+
+  describe("Arrange as Grid", () => {
+    it("should call onNodesChange when arrange as grid button is clicked", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 } }),
+            createMockNode("node-2", { position: { x: 100, y: 100 } }),
+            createMockNode("node-3", { position: { x: 200, y: 200 } }),
+            createMockNode("node-4", { position: { x: 300, y: 300 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const gridButton = screen.getByTitle("Arrange as grid (G)");
+      fireEvent.click(gridButton);
+
+      expect(mockOnNodesChange).toHaveBeenCalled();
+    });
+
+    it("should arrange nodes in a grid pattern", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 } }),
+            createMockNode("node-2", { position: { x: 500, y: 0 } }),
+            createMockNode("node-3", { position: { x: 0, y: 500 } }),
+            createMockNode("node-4", { position: { x: 500, y: 500 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      fireEvent.click(screen.getByTitle("Arrange as grid (G)"));
+
+      // With 4 nodes, should create a 2x2 grid
+      expect(mockOnNodesChange).toHaveBeenCalled();
+    });
+  });
+
+  describe("Create Group", () => {
+    it("should call createGroup with selected node IDs when create group button is clicked", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 } }),
+            createMockNode("node-2", { position: { x: 300, y: 0 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const createGroupButton = screen.getByTitle("Create group");
+      fireEvent.click(createGroupButton);
+
+      expect(mockCreateGroup).toHaveBeenCalledWith(["node-1", "node-2"]);
+    });
+
+    it("should show ungroup button when selected nodes are in a group", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 }, groupId: "group-1" }),
+            createMockNode("node-2", { position: { x: 300, y: 0 }, groupId: "group-1" }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Remove from group")).toBeInTheDocument();
+      expect(screen.queryByTitle("Create group")).not.toBeInTheDocument();
+    });
+
+    it("should call removeNodesFromGroup when ungroup button is clicked", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 }, groupId: "group-1" }),
+            createMockNode("node-2", { position: { x: 300, y: 0 }, groupId: "group-1" }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const ungroupButton = screen.getByTitle("Remove from group");
+      fireEvent.click(ungroupButton);
+
+      expect(mockRemoveNodesFromGroup).toHaveBeenCalledWith(["node-1", "node-2"]);
+    });
+
+    it("should show ungroup button when at least one selected node is in a group", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 }, groupId: "group-1" }),
+            createMockNode("node-2", { position: { x: 300, y: 0 } }), // Not in a group
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Remove from group")).toBeInTheDocument();
+    });
+  });
+
+  describe("Download Images", () => {
+    it("should render download images button", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 } }),
+            createMockNode("node-2", { position: { x: 300, y: 0 } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      expect(screen.getByTitle("Download images as ZIP")).toBeInTheDocument();
+    });
+
+    it("should not download when no images are available", async () => {
+      // Mock URL.createObjectURL and URL.revokeObjectURL
+      const createObjectURLSpy = vi.fn();
+      const revokeObjectURLSpy = vi.fn();
+      global.URL.createObjectURL = createObjectURLSpy;
+      global.URL.revokeObjectURL = revokeObjectURLSpy;
+
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { type: "prompt", position: { x: 0, y: 0 }, data: { prompt: "test" } }),
+            createMockNode("node-2", { type: "prompt", position: { x: 300, y: 0 }, data: { prompt: "test2" } }),
+          ],
+        }));
+      });
+
+      render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const downloadButton = screen.getByTitle("Download images as ZIP");
+      fireEvent.click(downloadButton);
+
+      // Should not create object URL when no images
+      expect(createObjectURLSpy).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("Toolbar Position", () => {
+    it("should position toolbar based on selected nodes bounding box", () => {
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 100, y: 200 } }),
+            createMockNode("node-2", { position: { x: 400, y: 200 } }),
+          ],
+        }));
+      });
+
+      const { container } = render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const toolbar = container.firstChild as HTMLElement;
+      expect(toolbar).toHaveStyle({ transform: "translateX(-50%)" });
+    });
+
+    it("should account for viewport zoom in positioning", () => {
+      mockGetViewport.mockReturnValue({ x: 100, y: 50, zoom: 2 });
+
+      mockUseWorkflowStore.mockImplementation((selector) => {
+        return selector(createDefaultState({
+          nodes: [
+            createMockNode("node-1", { position: { x: 0, y: 0 } }),
+            createMockNode("node-2", { position: { x: 200, y: 0 } }),
+          ],
+        }));
+      });
+
+      const { container } = render(
+        <TestWrapper>
+          <MultiSelectToolbar />
+        </TestWrapper>
+      );
+
+      const toolbar = container.firstChild as HTMLElement;
+      expect(toolbar).toBeInTheDocument();
+    });
+  });
+});