diff --git a/frontend/src/components/InlineEditCell.test.tsx b/frontend/src/components/InlineEditCell.test.tsx
index 3b43af3..8e7f1ec 100644
--- a/frontend/src/components/InlineEditCell.test.tsx
+++ b/frontend/src/components/InlineEditCell.test.tsx
@@ -103,4 +103,89 @@ describe('InlineEditCell', () => {
 
     expect(onSave).toHaveBeenCalledWith(99)
   })
+
+  // New tests for pencil icon and callbacks
+  it('renders a pencil icon in display mode', () => {
+    render(
+      <Wrapper>
+        <InlineEditCell {...defaultProps} />
+      </Wrapper>
+    )
+    // Pencil icon from lucide-react renders as an SVG — query by its test-id or aria role
+    // The Pencil icon should be present in the DOM (opacity-0, shown on hover via CSS)
+    const pencilIcon = document.querySelector('svg[data-testid="pencil-icon"]') ||
+      document.querySelector('.lucide-pencil')
+    expect(pencilIcon).not.toBeNull()
+  })
+
+  it('calls onSaveSuccess callback after successful save', async () => {
+    const user = userEvent.setup()
+    const onSave = vi.fn().mockResolvedValue(undefined)
+    const onSaveSuccess = vi.fn()
+    render(
+      <Wrapper>
+        <InlineEditCell {...defaultProps} onSave={onSave} onSaveSuccess={onSaveSuccess} />
+      </Wrapper>
+    )
+    const span = screen.getByText(/42/)
+    await user.click(span)
+
+    const input = screen.getByRole('spinbutton')
+    await user.clear(input)
+    await user.type(input, '100')
+    fireEvent.blur(input)
+
+    // Wait for async operations
+    await vi.waitFor(() => {
+      expect(onSaveSuccess).toHaveBeenCalledTimes(1)
+    })
+  })
+
+  it('calls onSaveError and reverts value when onSave rejects', async () => {
+    const user = userEvent.setup()
+    const onSave = vi.fn().mockRejectedValue(new Error('Save failed'))
+    const onSaveError = vi.fn()
+    render(
+      <Wrapper>
+        <InlineEditCell {...defaultProps} value={42.5} onSave={onSave} onSaveError={onSaveError} />
+      </Wrapper>
+    )
+    const span = screen.getByText(/42/)
+    await user.click(span)
+
+    const input = screen.getByRole('spinbutton')
+    await user.clear(input)
+    await user.type(input, '999')
+    fireEvent.blur(input)
+
+    // Wait for async operations
+    await vi.waitFor(() => {
+      expect(onSaveError).toHaveBeenCalledTimes(1)
+    })
+
+    // Value should revert back to original — display mode shows original value
+    await vi.waitFor(() => {
+      expect(screen.getByText(/42/)).toBeInTheDocument()
+    })
+  })
+
+  it('does not call onSaveSuccess when value is unchanged', async () => {
+    const user = userEvent.setup()
+    const onSave = vi.fn().mockResolvedValue(undefined)
+    const onSaveSuccess = vi.fn()
+    render(
+      <Wrapper>
+        <InlineEditCell {...defaultProps} onSave={onSave} onSaveSuccess={onSaveSuccess} />
+      </Wrapper>
+    )
+    const span = screen.getByText(/42/)
+    await user.click(span)
+
+    // Don't change the value, just blur
+    const input = screen.getByRole('spinbutton')
+    fireEvent.blur(input)
+
+    expect(onSave).not.toHaveBeenCalled()
+    expect(onSaveSuccess).not.toHaveBeenCalled()
+  })
 })