Support GPT-5.6 max and ultra reasoning levels

src/api/codexGateway.test.ts

@@ -1,5 +1,5 @@
 import { afterEach, describe, expect, it, vi } from 'vitest'
-import { getAvailableModelIds, getThreadDetail, listDirectoryComposioConnectors, resumeThread, startThreadTurn } from './codexGateway'
+import { getAvailableModelIds, getCurrentModelConfig, getThreadDetail, listDirectoryComposioConnectors, resumeThread, startThreadTurn } from './codexGateway'
 
 function mockRpcFetch(): { requests: Array<{ method: string, params: Record<string, unknown> }> } {
   const requests: Array<{ method: string, params: Record<string, unknown> }> = []
@@ -59,6 +59,48 @@ describe('startThreadTurn collaboration mode payloads', () => {
       },
     })
   })
+
+  it('passes GPT-5.6 ultra reasoning through to Codex', async () => {
+    const { requests } = mockRpcFetch()
+
+    await startThreadTurn('thread-1', 'solve it', [], 'gpt-5.6-sol', 'ultra', undefined, [], 'default')
+
+    expect(requests[0].params.effort).toBe('ultra')
+    expect(requests[0].params.collaborationMode).toEqual({
+      mode: 'default',
+      settings: {
+        model: 'gpt-5.6-sol',
+        reasoning_effort: 'ultra',
+        developer_instructions: null,
+      },
+    })
+  })
+})
+
+describe('getCurrentModelConfig', () => {
+  afterEach(() => {
+    vi.unstubAllGlobals()
+  })
+
+  it.each(['max', 'ultra'] as const)('keeps the GPT-5.6 %s reasoning level', async (reasoningEffort) => {
+    vi.stubGlobal('fetch', vi.fn(async () => new Response(JSON.stringify({
+      result: {
+        config: {
+          model: 'gpt-5.6-sol',
+          model_provider: 'openai',
+          model_reasoning_effort: reasoningEffort,
+        },
+      },
+    }), {
+      status: 200,
+      headers: { 'Content-Type': 'application/json' },
+    })))
+
+    await expect(getCurrentModelConfig()).resolves.toMatchObject({
+      model: 'gpt-5.6-sol',
+      reasoningEffort,
+    })
+  })
 })
 
 describe('listDirectoryComposioConnectors', () => {

src/api/codexGateway.ts

@@ -12,14 +12,14 @@ import type {
   ConfigReadResponse,
   GetAccountRateLimitsResponse,
   ModelListResponse,
-  ReasoningEffort,
   ThreadForkResponse,
   ThreadListResponse,
   ThreadReadResponse,
   ThreadResumeResponse,
   ThreadStartResponse,
   Turn,
 } from './appServerDtos'
+import { isReasoningEffort } from '../types/codex'
 import { extractErrorMessage, normalizeCodexApiError } from './codexErrors'
 import {
   readActiveTurnIdFromResponse,
@@ -53,6 +53,7 @@ import type {
   UiReviewWorkspaceView,
   UiRateLimitSnapshot,
   UiRateLimitWindow,
+  ReasoningEffort,
   UiThreadAutomation,
   UiThreadAutomationStatus,
 } from '../types/codex'
@@ -700,10 +701,7 @@ async function enrichThreadMessagesWithFallback(threadId: string, messages: UiMe
 }
 
 function normalizeReasoningEffort(value: unknown): ReasoningEffort | '' {
-  const allowed: ReasoningEffort[] = ['none', 'minimal', 'low', 'medium', 'high', 'xhigh']
-  return typeof value === 'string' && allowed.includes(value as ReasoningEffort)
-    ? (value as ReasoningEffort)
-    : ''
+  return isReasoningEffort(value) ? value : ''
 }
 
 function normalizeSpeedMode(value: unknown): SpeedMode {

src/components/content/ThreadComposer.vue

@@ -287,7 +287,7 @@
           />
 
           <ComposerDropdown
-            class="thread-composer-control"
+            class="thread-composer-control thread-composer-thinking-control"
             :model-value="selectedReasoningEffort"
             :options="reasoningOptions"
             :placeholder="t('Thinking')"
@@ -592,6 +592,8 @@ const reasoningOptions: Array<{ value: ReasoningEffort; label: string }> = [
   { value: 'medium', label: 'Medium' },
   { value: 'high', label: 'High' },
   { value: 'xhigh', label: 'Extra high' },
+  { value: 'max', label: 'Max' },
+  { value: 'ultra', label: 'Ultra' },
 ]
 function formatModelLabel(modelId: string): string {
   return modelId.trim().replace(/^gpt/i, 'GPT')
@@ -2214,6 +2216,9 @@ watch(
   @apply truncate;
 }
 
+.thread-composer-thinking-control :deep(.composer-dropdown-options) {
+  @apply max-h-64;
+}
 
 .thread-composer-actions {
   @apply ml-auto flex min-w-0 items-center gap-2;

src/composables/useDesktopState.ts

@@ -39,6 +39,7 @@ import {
 } from '../api/codexGateway'
 import { CodexApiError } from '../api/codexErrors'
 import { normalizeFileChangeStatus, toUiFileChanges } from '../api/normalizers/v2'
+import { REASONING_EFFORTS } from '../types/codex'
 import type {
   CollaborationModeKind,
   CollaborationModeOption,
@@ -91,7 +92,7 @@ const TURN_START_FOLLOW_UP_SYNC_DELAY_MS = 3000
 const RECENT_THREAD_MESSAGE_LOAD_REUSE_MS = 2000
 const RECENT_THREAD_LIST_LOAD_REUSE_MS = 2000
 const RECENT_SKILLS_LOAD_REUSE_MS = 2000
-const REASONING_EFFORT_OPTIONS: ReasoningEffort[] = ['none', 'minimal', 'low', 'medium', 'high', 'xhigh']
+const REASONING_EFFORT_OPTIONS: readonly ReasoningEffort[] = REASONING_EFFORTS
 const GLOBAL_SERVER_REQUEST_SCOPE = '__global__'
 const MODEL_FALLBACK_ID = 'gpt-5.4-mini'
 const OPENCODE_ZEN_DEFAULT_MODEL = 'big-pickle'

src/server/codexAppServerBridge.ts

@@ -46,7 +46,7 @@ import {
   resolveCodexCommand,
   resolveRipgrepCommand,
 } from '../commandResolution.js'
-import type { CollaborationModeKind, ReasoningEffort } from '../types/codex.js'
+import { isReasoningEffort, type CollaborationModeKind, type ReasoningEffort } from '../types/codex.js'
 import { isAbsoluteLikePath } from '../pathUtils.js'
 
 type JsonRpcCall = {
@@ -5674,10 +5674,7 @@ async function appendThreadQueuedMessage(threadId: string, message: StoredQueued
 }
 
 function normalizeReasoningEffort(value: unknown): ReasoningEffort | '' {
-  const allowed: ReasoningEffort[] = ['none', 'minimal', 'low', 'medium', 'high', 'xhigh']
-  return typeof value === 'string' && allowed.includes(value as ReasoningEffort)
-    ? (value as ReasoningEffort)
-    : ''
+  return isReasoningEffort(value) ? value : ''
 }
 
 function normalizeCollaborationModeReasoningEffort(value: ReasoningEffort | '' | null | undefined): ReasoningEffort | null {

src/types/codex.ts

@@ -2,7 +2,22 @@ export type RpcEnvelope<T> = {
   result: T
 }
 
-export type ReasoningEffort = 'none' | 'minimal' | 'low' | 'medium' | 'high' | 'xhigh'
+export const REASONING_EFFORTS = [
+  'none',
+  'minimal',
+  'low',
+  'medium',
+  'high',
+  'xhigh',
+  'max',
+  'ultra',
+] as const
+
+export type ReasoningEffort = (typeof REASONING_EFFORTS)[number]
+
+export function isReasoningEffort(value: unknown): value is ReasoningEffort {
+  return typeof value === 'string' && REASONING_EFFORTS.some((effort) => effort === value)
+}
 export type SpeedMode = 'standard' | 'fast'
 export type CollaborationModeKind = 'default' | 'plan'
 

tests/providers-models/gpt-5-6-max-and-ultra-thinking-levels.md

@@ -0,0 +1,28 @@
+### GPT-5.6 Max and Ultra thinking levels
+
+#### Feature/Change Name
+GPT-5.6 reasoning-level selection supports the new `max` and `ultra` values.
+
+#### Prerequisites/Setup
+1. Install a Codex CLI version whose model catalog includes GPT-5.6 and its new reasoning levels.
+2. Sign in with an account that can use a GPT-5.6 model.
+3. Build and start the app.
+
+#### Steps
+1. Start a new chat and select `GPT-5.6-Sol` or another available GPT-5.6 model.
+2. Open the Thinking selector in light theme and confirm `Max` and `Ultra` are present.
+3. Select `Max`, send a prompt, and confirm the turn starts without an invalid reasoning-effort error.
+4. Select `Ultra`, send a second prompt, and confirm the turn starts without an invalid reasoning-effort error.
+5. Switch to dark theme and repeat the selector visibility check.
+6. Reload the page while `Ultra` is configured and confirm the selector still displays `Ultra`.
+
+#### Expected Results
+- The Thinking selector includes `Max` and `Ultra` after `Extra high`.
+- Selecting either value passes the exact lowercase `max` or `ultra` value to Codex.
+- A configured `max` or `ultra` value survives config normalization and appears selected after refresh.
+- The options remain readable in light and dark themes.
+
+#### Rollback/Cleanup
+- Restore the preferred model and thinking level.
+
+---

tests/providers-models/index.md

@@ -34,3 +34,4 @@ Return to the [manual test index](../../tests.md).
 | [Thread-locked providers across Zen, Codex, and OpenRouter](thread-locked-providers-across-zen-codex-and-openrouter.md) |
 | [Selected thread loads do not refetch provider models](selected-thread-loads-do-not-refetch-provider-models.md) |
 | [Provider-backed scheduled refreshes keep model menus populated](provider-backed-scheduled-refreshes-keep-model-menus-populated.md) |
+| [GPT-5.6 Max and Ultra thinking levels](gpt-5-6-max-and-ultra-thinking-levels.md) |