diff --git a/src/components/studio/views/graph-view-coverage.test.tsx b/src/components/studio/views/graph-view-coverage.test.tsx
new file mode 100644
index 00000000..a4c729be
--- /dev/null
+++ b/src/components/studio/views/graph-view-coverage.test.tsx
@@ -0,0 +1,314 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest'
+import type { ReactNode } from 'react'
+import { render, screen, fireEvent, cleanup } from '@testing-library/react'
+
+vi.mock('lucide-react', () => {
+  const I = ({ className }: { className?: string }) => (
+    <span data-testid="icon" className={className} />
+  )
+  return {
+    CircleDot: I,
+    Circle: I,
+    GitFork: I,
+    Layers: I,
+    Focus: I,
+    Camera: I,
+    RotateCcw: I,
+    RotateCw: I,
+    Download: I,
+  }
+})
+
+vi.mock('@/lib/studio/use-reduced-motion', () => ({
+  useReducedMotion: () => true,
+}))
+
+vi.mock('@/lib/utils', () => ({
+  cn: (...args: (string | undefined | false | null)[]) => args.filter(Boolean).join(' '),
+}))
+
+vi.mock('../ui/shared-primitives', () => ({
+  ToggleButtonGroup: ({ children, label }: { children?: ReactNode; label?: string }) => (
+    <div data-testid="toggle-button-group" aria-label={label}>{children}</div>
+  ),
+  Divider: () => <hr data-testid="divider" />,
+}))
+
+vi.mock('sonner', () => ({
+  toast: { success: vi.fn(), error: vi.fn(), info: vi.fn() },
+}))
+
+const mockSelectEntity = vi.fn()
+const mockUndo = vi.fn()
+const mockRedo = vi.fn()
+
+const mockEntities = [
+  {
+    id: 'ent-1',
+    name: 'Test Entity',
+    type: 'note' as const,
+    description: 'desc',
+    content: '',
+    tags: [],
+    createdAt: new Date().toISOString(),
+    updatedAt: new Date().toISOString(),
+    links: [{ targetId: 'ent-2', relation: 'related' }],
+  },
+  {
+    id: 'ent-2',
+    name: 'Linked Entity',
+    type: 'concept' as const,
+    description: 'desc',
+    content: '',
+    tags: [],
+    createdAt: new Date().toISOString(),
+    updatedAt: new Date().toISOString(),
+    links: [],
+  },
+]
+
+let currentEntities = mockEntities
+let currentSelectedEntityId: string | null = null
+let currentHistoryIndex = 0
+let currentEntityHistory: unknown[][] = [[]]
+
+vi.mock('@/lib/studio/store', () => ({
+  useStudioStore: (selector: (s: Record<string, unknown>) => unknown) =>
+    selector({
+      entities: currentEntities,
+      selectedEntityId: currentSelectedEntityId,
+      selectEntity: mockSelectEntity,
+      undo: mockUndo,
+      redo: mockRedo,
+      entityHistory: currentEntityHistory,
+      historyIndex: currentHistoryIndex,
+    }),
+}))
+
+import { GraphView } from './graph-view'
+
+describe('GraphView branch coverage', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    currentEntities = mockEntities
+    currentSelectedEntityId = null
+    currentHistoryIndex = 0
+    currentEntityHistory = [[]]
+    vi.spyOn(Storage.prototype, 'setItem').mockImplementation(() => {})
+    vi.spyOn(Storage.prototype, 'getItem').mockReturnValue(null)
+  })
+
+  afterEach(() => {
+    cleanup()
+    vi.restoreAllMocks()
+  })
+
+  it('renders empty state when no entities', () => {
+    currentEntities = []
+    render(<GraphView />)
+    expect(screen.getByText('No entities to graph yet.')).toBeDefined()
+  })
+
+  it('switches to circular layout when button clicked', () => {
+    render(<GraphView />)
+    const circularBtn = screen.getByText('circular')
+    fireEvent.click(circularBtn)
+    expect(circularBtn).toHaveAttribute('aria-pressed', 'true')
+  })
+
+  it('switches to hierarchical layout when button clicked', () => {
+    render(<GraphView />)
+    const hierBtn = screen.getByText('hierarchical')
+    fireEvent.click(hierBtn)
+    expect(hierBtn).toHaveAttribute('aria-pressed', 'true')
+  })
+
+  it('switches back to force layout when force button clicked', () => {
+    render(<GraphView />)
+    fireEvent.click(screen.getByText('circular'))
+    fireEvent.click(screen.getByText('force'))
+    expect(screen.getByText('force')).toHaveAttribute('aria-pressed', 'true')
+  })
+
+  it('toggles focus mode on and off', () => {
+    currentSelectedEntityId = 'ent-1'
+    render(<GraphView />)
+    const focusBtn = screen.getByLabelText('Focus neighborhood')
+    fireEvent.click(focusBtn)
+    expect(focusBtn).toHaveAttribute('aria-pressed', 'true')
+    fireEvent.click(focusBtn)
+    expect(focusBtn).toHaveAttribute('aria-pressed', 'false')
+  })
+
+  it('selects entity on node click', () => {
+    render(<GraphView />)
+    const node = screen.getByRole('button', { name: /Test Entity/ })
+    fireEvent.click(node)
+    expect(mockSelectEntity).toHaveBeenCalledWith('ent-1')
+  })
+
+  it('deselects entity on click when already selected', () => {
+    currentSelectedEntityId = 'ent-1'
+    render(<GraphView />)
+    const node = screen.getByRole('button', { name: /Test Entity/ })
+    fireEvent.click(node)
+    expect(mockSelectEntity).toHaveBeenCalledWith(null)
+  })
+
+  it('selects entity on Enter key', () => {
+    render(<GraphView />)
+    const node = screen.getByRole('button', { name: /Test Entity/ })
+    fireEvent.keyDown(node, { key: 'Enter' })
+    expect(mockSelectEntity).toHaveBeenCalledWith('ent-1')
+  })
+
+  it('selects entity on Space key', () => {
+    render(<GraphView />)
+    const node = screen.getByRole('button', { name: /Test Entity/ })
+    fireEvent.keyDown(node, { key: ' ' })
+    expect(mockSelectEntity).toHaveBeenCalledWith('ent-1')
+  })
+
+  it('focuses node and tracks focusedNodeId', () => {
+    render(<GraphView />)
+    const node = screen.getByRole('button', { name: /Test Entity/ })
+    fireEvent.focus(node)
+    // Focus sets focusedNodeId to the node id
+    expect(node).toHaveAttribute('tabIndex', '0')
+  })
+
+  it('calls undo when undo button clicked', () => {
+    currentHistoryIndex = 1
+    currentEntityHistory = [[], []]
+    render(<GraphView />)
+    const undoBtn = screen.getByLabelText('Undo')
+    fireEvent.click(undoBtn)
+    expect(mockUndo).toHaveBeenCalled()
+  })
+
+  it('calls redo when redo button clicked', () => {
+    currentEntityHistory = [[], []]
+    render(<GraphView />)
+    const redoBtn = screen.getByLabelText('Redo')
+    fireEvent.click(redoBtn)
+    expect(mockRedo).toHaveBeenCalled()
+  })
+
+  it('saves snapshot when save snapshot button clicked', () => {
+    render(<GraphView />)
+    const snapshotBtn = screen.getByLabelText('Save snapshot')
+    fireEvent.click(snapshotBtn)
+    expect(localStorage.setItem).toHaveBeenCalledWith(
+      'dks-graph-snapshot',
+      expect.any(String),
+    )
+  })
+
+  it('renders entity type legend', () => {
+    render(<GraphView />)
+    expect(screen.getByText('Entity types')).toBeDefined()
+    expect(screen.getByText('Note')).toBeDefined()
+    expect(screen.getByText('Concept')).toBeDefined()
+    expect(screen.getByText('Person')).toBeDefined()
+    expect(screen.getByText('Project')).toBeDefined()
+  })
+
+  it('shows correct node and edge counts', () => {
+    render(<GraphView />)
+    expect(screen.getByText(/2 nodes · 1 edges/)).toBeDefined()
+  })
+
+  it('shows correct counts with focus mode enabled (only selected + neighbors)', () => {
+    currentSelectedEntityId = 'ent-1'
+    render(<GraphView />)
+    const focusBtn = screen.getByLabelText('Focus neighborhood')
+    fireEvent.click(focusBtn)
+    expect(screen.getByText(/2 nodes · 1 edges/)).toBeDefined()
+  })
+
+  it('removes edges when entity type is filtered', () => {
+    // When a node has a link to a non-existent target, the link should be filtered out
+    const entitiesWithBadLink = [
+      {
+        id: 'ent-1',
+        name: 'Entity 1',
+        type: 'note' as const,
+        description: '',
+        content: '',
+        tags: [],
+        createdAt: new Date().toISOString(),
+        updatedAt: new Date().toISOString(),
+        links: [{ targetId: 'non-existent', relation: 'related' }],
+      },
+    ]
+    currentEntities = entitiesWithBadLink
+    render(<GraphView />)
+    expect(screen.getByText(/1 nodes · 0 edges/)).toBeDefined()
+  })
+
+  it('removes duplicate edges between same nodes', () => {
+    const entitiesWithDupLinks = [
+      {
+        id: 'ent-1',
+        name: 'Entity 1',
+        type: 'note' as const,
+        description: '',
+        content: '',
+        tags: [],
+        createdAt: new Date().toISOString(),
+        updatedAt: new Date().toISOString(),
+        links: [
+          { targetId: 'ent-2', relation: 'related' },
+          { targetId: 'ent-2', relation: 'related' },
+        ],
+      },
+      {
+        id: 'ent-2',
+        name: 'Entity 2',
+        type: 'note' as const,
+        description: '',
+        content: '',
+        tags: [],
+        createdAt: new Date().toISOString(),
+        updatedAt: new Date().toISOString(),
+        links: [],
+      },
+    ]
+    currentEntities = entitiesWithDupLinks
+    render(<GraphView />)
+    expect(screen.getByText(/2 nodes · 1 edges/)).toBeDefined()
+  })
+
+  it('renders edge label when a node is selected (highlighted edge)', () => {
+    currentSelectedEntityId = 'ent-1'
+    render(<GraphView />)
+    // The relation label is rendered as SVG <text> in the highlighted edge
+    expect(screen.getByRole('img', { name: /knowledge graph/ })).toBeDefined()
+  })
+
+  it('shows label truncation for long names', () => {
+    const longNameEntity = [
+      {
+        id: 'ent-1',
+        name: 'A very long entity name that should be truncated at 24 characters',
+        type: 'note' as const,
+        description: '',
+        content: '',
+        tags: [],
+        createdAt: new Date().toISOString(),
+        updatedAt: new Date().toISOString(),
+        links: [],
+      },
+    ]
+    currentEntities = longNameEntity
+    render(<GraphView />)
+    const node = screen.getByRole('button', { name: /A very long entity/ })
+    expect(node).toBeDefined()
+  })
+
+  it('renders no edges for empty entity list', () => {
+    currentEntities = []
+    render(<GraphView />)
+    expect(screen.getByText('No entities to graph yet.')).toBeDefined()
+  })
+})