diff --git a/src/hooks/auto-update-checker/hook.test.ts b/src/hooks/auto-update-checker/hook.test.ts
index b7d8e5232..4a8096bb9 100644
--- a/src/hooks/auto-update-checker/hook.test.ts
+++ b/src/hooks/auto-update-checker/hook.test.ts
@@ -1,8 +1,13 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { describe, expect, mock, test } from "bun:test"
 
+type CreateAutoUpdateCheckerHook = typeof import("./hook").createAutoUpdateCheckerHook
+type HookOptions = Parameters<CreateAutoUpdateCheckerHook>[1]
+type HookDeps = NonNullable<Parameters<CreateAutoUpdateCheckerHook>[2]>
+
 let latestVersionCallCount = 0
 let scheduleDeferredIdleCheckCallCount = 0
+
 const flushMicrotasks = async (count: number): Promise<void> => {
   for (let index = 0; index < count; index += 1) {
     await Promise.resolve()
@@ -29,72 +34,192 @@ mock.module("./hook/deferred-idle-check", () => ({
   scheduleDeferredIdleCheck: scheduleDeferredIdleCheckMock,
 }))
 
-const createHook = async () => {
+const createPluginInput = (): PluginInput => ({
+  client: {} as PluginInput["client"],
+  directory: "/tmp/project",
+  project: {} as PluginInput["project"],
+  worktree: "/tmp/project",
+  serverUrl: new URL("https://example.com"),
+  $: {} as PluginInput["$"],
+} satisfies PluginInput)
+
+const createDeps = (overrides: Partial<HookDeps> = {}) => {
+  const showConfigErrorsIfAny = mock(async () => undefined)
+  const updateAndShowConnectedProvidersCacheStatus = mock(async () => undefined)
+  const refreshModelCapabilitiesOnStartup = mock(async () => undefined)
+  const showModelCacheWarningIfNeeded = mock(async () => undefined)
+  const showLocalDevToast = mock(async () => undefined)
+  const showVersionToast = mock(async () => undefined)
+  const runBackgroundUpdateCheck = mock(async () => {
+    await latestVersionMock()
+  })
+
+  const deps: HookDeps = {
+    getCachedVersion: () => "3.0.0",
+    getLocalDevVersion: () => null,
+    showConfigErrorsIfAny,
+    updateAndShowConnectedProvidersCacheStatus,
+    refreshModelCapabilitiesOnStartup,
+    showModelCacheWarningIfNeeded,
+    showLocalDevToast,
+    showVersionToast,
+    runBackgroundUpdateCheck,
+    log: () => undefined,
+    ...overrides,
+  }
+
+  return {
+    deps,
+    mocks: {
+      showConfigErrorsIfAny,
+      updateAndShowConnectedProvidersCacheStatus,
+      refreshModelCapabilitiesOnStartup,
+      showModelCacheWarningIfNeeded,
+      showLocalDevToast,
+      showVersionToast,
+      runBackgroundUpdateCheck,
+    },
+  }
+}
+
+const createHook = async (
+  options: HookOptions = {},
+  overrides: Partial<HookDeps> = {},
+) => {
   const module = await import("./hook")
-  return module.createAutoUpdateCheckerHook(
-    {
-      directory: "/tmp/project",
-      client: {
-        tui: {
-          showToast: async () => undefined,
-        },
+  const { deps, mocks } = createDeps(overrides)
+
+  return {
+    hook: module.createAutoUpdateCheckerHook(
+      createPluginInput(),
+      {
+        showStartupToast: true,
+        autoUpdate: false,
+        ...options,
       },
-    } satisfies PluginInput,
-    {
-      showStartupToast: false,
-      autoUpdate: false,
-    },
-    {
-      getCachedVersion: () => "3.0.0",
-      getLocalDevVersion: () => null,
-      showConfigErrorsIfAny: async () => undefined,
-      updateAndShowConnectedProvidersCacheStatus: async () => undefined,
-      refreshModelCapabilitiesOnStartup: async () => undefined,
-      showModelCacheWarningIfNeeded: async () => undefined,
-      showLocalDevToast: async () => undefined,
-      showVersionToast: async () => undefined,
-      runBackgroundUpdateCheck: async () => {
-        await latestVersionMock()
-      },
-      log: () => undefined,
-    },
-  )
+      deps,
+    ),
+    mocks,
+  }
+}
+
+const resetDeferredState = (): void => {
+  latestVersionCallCount = 0
+  scheduleDeferredIdleCheckCallCount = 0
+  scheduledCheck = null
+}
+
+const triggerDeferredIdleCheck = async (
+  hook: ReturnType<CreateAutoUpdateCheckerHook>,
+): Promise<void> => {
+  hook.event({ event: { type: "session.idle" } })
+  scheduledCheck?.()
+  await flushMicrotasks(8)
 }
 
 describe("auto-update-checker hook", () => {
   test("defers update check until first session idle", async () => {
     // given
-    latestVersionCallCount = 0
-    scheduleDeferredIdleCheckCallCount = 0
-    scheduledCheck = null
-    const hook = await createHook()
+    resetDeferredState()
+    const { hook, mocks } = await createHook()
 
     // when
     hook.event({ event: { type: "session.created" } })
 
     // then
     expect(scheduleDeferredIdleCheckCallCount).toBe(0)
+    expect(mocks.showVersionToast).not.toHaveBeenCalled()
+    expect(mocks.runBackgroundUpdateCheck).not.toHaveBeenCalled()
     expect(latestVersionCallCount).toBe(0)
 
+    // when
+    await triggerDeferredIdleCheck(hook)
+
+    // then
+    expect(scheduleDeferredIdleCheckCallCount).toBe(1)
+    expect(mocks.showVersionToast).toHaveBeenCalledTimes(1)
+    expect(mocks.runBackgroundUpdateCheck).toHaveBeenCalledTimes(1)
+    expect(latestVersionCallCount).toBe(1)
+
     // when
     hook.event({ event: { type: "session.idle" } })
 
     // then
     expect(scheduleDeferredIdleCheckCallCount).toBe(1)
-    expect(latestVersionCallCount).toBe(0)
+    expect(mocks.runBackgroundUpdateCheck).toHaveBeenCalledTimes(1)
+  })
+
+  test("runs all startup checks on normal session.idle", async () => {
+    // given
+    resetDeferredState()
+    const { hook, mocks } = await createHook()
 
     // when
-    await scheduledCheck?.()
+    await triggerDeferredIdleCheck(hook)
+
+    // then
+    expect(mocks.showConfigErrorsIfAny).toHaveBeenCalledTimes(1)
+    expect(mocks.updateAndShowConnectedProvidersCacheStatus).toHaveBeenCalledTimes(1)
+    expect(mocks.refreshModelCapabilitiesOnStartup).toHaveBeenCalledTimes(1)
+    expect(mocks.showModelCacheWarningIfNeeded).toHaveBeenCalledTimes(1)
+    expect(mocks.showVersionToast).toHaveBeenCalledTimes(1)
+    expect(mocks.runBackgroundUpdateCheck).toHaveBeenCalledTimes(1)
+  })
+
+  test("runs only once (hasChecked guard)", async () => {
+    // given
+    resetDeferredState()
+    const { hook, mocks } = await createHook()
+
+    // when
+    hook.event({ event: { type: "session.idle" } })
+    hook.event({ event: { type: "session.idle" } })
+    scheduledCheck?.()
     await flushMicrotasks(8)
 
     // then
-    expect(latestVersionCallCount).toBe(1)
+    expect(scheduleDeferredIdleCheckCallCount).toBe(1)
+    expect(mocks.showConfigErrorsIfAny).toHaveBeenCalledTimes(1)
+    expect(mocks.updateAndShowConnectedProvidersCacheStatus).toHaveBeenCalledTimes(1)
+    expect(mocks.showModelCacheWarningIfNeeded).toHaveBeenCalledTimes(1)
+    expect(mocks.showVersionToast).toHaveBeenCalledTimes(1)
+    expect(mocks.runBackgroundUpdateCheck).toHaveBeenCalledTimes(1)
+  })
+
+  test("shows localDevToast when local dev version exists", async () => {
+    // given
+    resetDeferredState()
+    const { hook, mocks } = await createHook({}, {
+      getLocalDevVersion: () => "3.0.0-dev",
+    })
 
     // when
-    hook.event({ event: { type: "session.idle" } })
+    await triggerDeferredIdleCheck(hook)
 
     // then
-    expect(scheduleDeferredIdleCheckCallCount).toBe(1)
-    expect(latestVersionCallCount).toBe(1)
+    expect(mocks.showConfigErrorsIfAny).toHaveBeenCalledTimes(1)
+    expect(mocks.updateAndShowConnectedProvidersCacheStatus).toHaveBeenCalledTimes(1)
+    expect(mocks.showModelCacheWarningIfNeeded).toHaveBeenCalledTimes(1)
+    expect(mocks.showLocalDevToast).toHaveBeenCalledTimes(1)
+    expect(mocks.showVersionToast).not.toHaveBeenCalled()
+    expect(mocks.runBackgroundUpdateCheck).not.toHaveBeenCalled()
+    expect(latestVersionCallCount).toBe(0)
+  })
+
+  test("passes correct toast message with sisyphus enabled", async () => {
+    // given
+    resetDeferredState()
+    const { hook, mocks } = await createHook({ isSisyphusEnabled: true })
+
+    // when
+    await triggerDeferredIdleCheck(hook)
+
+    // then
+    expect(mocks.showVersionToast).toHaveBeenCalledTimes(1)
+    expect(mocks.showVersionToast).toHaveBeenCalledWith(
+      expect.anything(),
+      "3.0.0",
+      expect.stringContaining("Sisyphus"),
+    )
   })
 })