diff --git a/web/frontend/src/__tests__/execution-mode-unification.test.ts b/web/frontend/src/__tests__/execution-mode-unification.test.ts
index 3beec72..6b526cf 100644
--- a/web/frontend/src/__tests__/execution-mode-unification.test.ts
+++ b/web/frontend/src/__tests__/execution-mode-unification.test.ts
@@ -144,7 +144,7 @@ describe('KIN-FIX-002: execution_mode унификация на "auto_complete"'
       const router = makeRouter()
       await router.push('/task/KIN-001')
 
-      const wrapper = mount(TaskDetail, {
+      mount(TaskDetail, {
         props: { id: 'KIN-001' },
         global: { plugins: [router] },
       })
@@ -191,7 +191,7 @@ describe('KIN-FIX-002: execution_mode унификация на "auto_complete"'
       const router = makeRouter()
       await router.push('/project/KIN')
 
-      const wrapper = mount(ProjectView, {
+      mount(ProjectView, {
         props: { id: 'KIN' },
         global: { plugins: [router] },
       })
@@ -278,7 +278,7 @@ describe('KIN-FIX-002: execution_mode унификация на "auto_complete"'
       const router = makeRouter()
       await router.push('/task/KIN-001')
 
-      const wrapper = mount(TaskDetail, {
+      mount(TaskDetail, {
         props: { id: 'KIN-001' },
         global: { plugins: [router] },
       })
@@ -291,3 +291,159 @@ describe('KIN-FIX-002: execution_mode унификация на "auto_complete"'
     })
   })
 })
+
+describe('KIN-077: кнопка Review/Auto — regression (400 Bad Request fix)', () => {
+  describe('ProjectView — patchProject вызывается с корректным enum-значением', () => {
+    it('при переключении review→auto отправляет "auto_complete", не "auto"', async () => {
+      const projectReview = { ...MOCK_PROJECT, execution_mode: 'review' }
+      vi.mocked(api.project).mockResolvedValue(projectReview as any)
+      vi.mocked(api.patchProject).mockResolvedValue({ execution_mode: 'auto_complete' } as any)
+
+      const router = makeRouter()
+      await router.push('/project/KIN')
+
+      const wrapper = mount(ProjectView, {
+        props: { id: 'KIN' },
+        global: { plugins: [router] },
+      })
+      await flushPromises()
+
+      const toggleBtn = wrapper.findAll('button').find(b =>
+        b.text().includes('Review') || b.text().includes('Auto')
+      )
+      expect(toggleBtn, 'кнопка тоггла должна быть найдена').toBeDefined()
+
+      await toggleBtn!.trigger('click')
+      await flushPromises()
+
+      // Главная проверка: patchProject вызван с 'auto_complete', не 'auto' (причина 400)
+      expect(vi.mocked(api.patchProject)).toHaveBeenCalledWith('KIN', {
+        execution_mode: 'auto_complete',
+      })
+      const callArg = vi.mocked(api.patchProject).mock.calls[0][1] as { execution_mode: string }
+      expect(callArg.execution_mode).not.toBe('auto')
+    })
+
+    it('при переключении auto→review отправляет "review"', async () => {
+      const projectAuto = { ...MOCK_PROJECT, execution_mode: 'auto_complete' }
+      vi.mocked(api.project).mockResolvedValue(projectAuto as any)
+      vi.mocked(api.patchProject).mockResolvedValue({ execution_mode: 'review' } as any)
+
+      const router = makeRouter()
+      await router.push('/project/KIN')
+
+      const wrapper = mount(ProjectView, {
+        props: { id: 'KIN' },
+        global: { plugins: [router] },
+      })
+      await flushPromises()
+
+      const toggleBtn = wrapper.findAll('button').find(b =>
+        b.text().includes('Auto') || b.text().includes('Review')
+      )
+      expect(toggleBtn).toBeDefined()
+
+      await toggleBtn!.trigger('click')
+      await flushPromises()
+
+      expect(vi.mocked(api.patchProject)).toHaveBeenCalledWith('KIN', {
+        execution_mode: 'review',
+      })
+    })
+  })
+
+  describe('ProjectView — кнопка отображает актуальный режим', () => {
+    it('когда проект в режиме "review" — кнопка показывает "Review"', async () => {
+      const projectReview = { ...MOCK_PROJECT, execution_mode: 'review' }
+      vi.mocked(api.project).mockResolvedValue(projectReview as any)
+
+      const router = makeRouter()
+      await router.push('/project/KIN')
+
+      const wrapper = mount(ProjectView, {
+        props: { id: 'KIN' },
+        global: { plugins: [router] },
+      })
+      await flushPromises()
+
+      const toggleBtn = wrapper.findAll('button').find(b =>
+        b.text().includes('Review') || b.text().includes('Auto')
+      )
+      expect(toggleBtn).toBeDefined()
+      expect(toggleBtn!.text()).toContain('Review')
+    })
+
+    it('когда проект в режиме "auto_complete" — кнопка показывает "Auto"', async () => {
+      const projectAuto = { ...MOCK_PROJECT, execution_mode: 'auto_complete' }
+      vi.mocked(api.project).mockResolvedValue(projectAuto as any)
+
+      const router = makeRouter()
+      await router.push('/project/KIN')
+
+      const wrapper = mount(ProjectView, {
+        props: { id: 'KIN' },
+        global: { plugins: [router] },
+      })
+      await flushPromises()
+
+      const toggleBtn = wrapper.findAll('button').find(b =>
+        b.text().includes('Auto') || b.text().includes('Review')
+      )
+      expect(toggleBtn).toBeDefined()
+      expect(toggleBtn!.text()).toContain('Auto')
+    })
+
+    it('после клика review→auto кнопка меняет текст на "Auto"', async () => {
+      const projectReview = { ...MOCK_PROJECT, execution_mode: 'review' }
+      vi.mocked(api.project).mockResolvedValue(projectReview as any)
+      vi.mocked(api.patchProject).mockResolvedValue({ execution_mode: 'auto_complete' } as any)
+
+      const router = makeRouter()
+      await router.push('/project/KIN')
+
+      const wrapper = mount(ProjectView, {
+        props: { id: 'KIN' },
+        global: { plugins: [router] },
+      })
+      await flushPromises()
+
+      const findToggleBtn = () =>
+        wrapper.findAll('button').find(b => b.text().includes('Auto') || b.text().includes('Review'))
+
+      expect(findToggleBtn()!.text()).toContain('Review')
+
+      await findToggleBtn()!.trigger('click')
+      await flushPromises()
+
+      expect(findToggleBtn()!.text()).toContain('Auto')
+    })
+
+    it('двойной клик возвращает кнопку обратно в "Review"', async () => {
+      const projectReview = { ...MOCK_PROJECT, execution_mode: 'review' }
+      vi.mocked(api.project).mockResolvedValue(projectReview as any)
+      vi.mocked(api.patchProject)
+        .mockResolvedValueOnce({ execution_mode: 'auto_complete' } as any)
+        .mockResolvedValueOnce({ execution_mode: 'review' } as any)
+
+      const router = makeRouter()
+      await router.push('/project/KIN')
+
+      const wrapper = mount(ProjectView, {
+        props: { id: 'KIN' },
+        global: { plugins: [router] },
+      })
+      await flushPromises()
+
+      const findToggleBtn = () =>
+        wrapper.findAll('button').find(b => b.text().includes('Auto') || b.text().includes('Review'))
+
+      await findToggleBtn()!.trigger('click')
+      await flushPromises()
+      expect(findToggleBtn()!.text()).toContain('Auto')
+
+      await findToggleBtn()!.trigger('click')
+      await flushPromises()
+      expect(findToggleBtn()!.text()).toContain('Review')
+    })
+  })
+})