diff --git a/frontend/src/components/keys/UseKeyModal.vue b/frontend/src/components/keys/UseKeyModal.vue
index 18440c60111..3077f2ed7e3 100644
--- a/frontend/src/components/keys/UseKeyModal.vue
+++ b/frontend/src/components/keys/UseKeyModal.vue
@@ -418,9 +418,9 @@ const currentFiles = computed((): FileConfig[] => {
         return generateAnthropicFiles(baseUrl, apiKey)
       }
       if (activeClientTab.value === 'codex-ws') {
-        return generateOpenAIWsFiles(baseUrl, apiKey)
+        return generateOpenAIWsFiles(apiBase, apiKey)
       }
-      return generateOpenAIFiles(baseUrl, apiKey)
+      return generateOpenAIFiles(apiBase, apiKey)
     case 'gemini':
       return [generateGeminiCliContent(baseUrl, apiKey)]
     case 'antigravity':
@@ -528,39 +528,40 @@ ${keyword('$env:')}${variable('GEMINI_MODEL')}${operator('=')}${string(`"${model
 function generateOpenAIFiles(baseUrl: string, apiKey: string): FileConfig[] {
   const isWindows = activeTab.value === 'windows'
   const configDir = isWindows ? '%userprofile%\\.codex' : '~/.codex'
+  const configPath = isWindows ? `${configDir}\\config.toml` : `${configDir}/config.toml`
+  const envCommand = isWindows
+    ? `setx OPENAI_API_KEY "${apiKey}"`
+    : `export OPENAI_API_KEY="${apiKey}"`
+  const envPath = isWindows ? 'Command Prompt / PowerShell' : 'Terminal'
 
   // config.toml content
-  const configContent = `model_provider = "OpenAI"
+  const configContent = `preferred_auth_method = "apikey"
 model = "gpt-5.5"
 review_model = "gpt-5.5"
+model_provider = "proxy"
 model_reasoning_effort = "xhigh"
 disable_response_storage = true
 network_access = "enabled"
 windows_wsl_setup_acknowledged = true
 
-[model_providers.OpenAI]
-name = "OpenAI"
+[model_providers.proxy]
+name = "OpenAi"
 base_url = "${baseUrl}"
+env_key = "OPENAI_API_KEY"
 wire_api = "responses"
-requires_openai_auth = true
 
 [features]
 goals = true`
 
-  // auth.json content
-  const authContent = `{
-  "OPENAI_API_KEY": "${apiKey}"
-}`
-
   return [
     {
-      path: `${configDir}/config.toml`,
+      path: configPath,
       content: configContent,
       hint: t('keys.useKeyModal.openai.configTomlHint')
     },
     {
-      path: `${configDir}/auth.json`,
-      content: authContent
+      path: envPath,
+      content: envCommand
     }
   ]
 }
@@ -568,41 +569,42 @@ goals = true`
 function generateOpenAIWsFiles(baseUrl: string, apiKey: string): FileConfig[] {
   const isWindows = activeTab.value === 'windows'
   const configDir = isWindows ? '%userprofile%\\.codex' : '~/.codex'
+  const configPath = isWindows ? `${configDir}\\config.toml` : `${configDir}/config.toml`
+  const envCommand = isWindows
+    ? `setx OPENAI_API_KEY "${apiKey}"`
+    : `export OPENAI_API_KEY="${apiKey}"`
+  const envPath = isWindows ? 'Command Prompt / PowerShell' : 'Terminal'
 
   // config.toml content with WebSocket v2
-  const configContent = `model_provider = "OpenAI"
+  const configContent = `preferred_auth_method = "apikey"
 model = "gpt-5.5"
 review_model = "gpt-5.5"
+model_provider = "proxy"
 model_reasoning_effort = "xhigh"
 disable_response_storage = true
 network_access = "enabled"
 windows_wsl_setup_acknowledged = true
 
-[model_providers.OpenAI]
-name = "OpenAI"
+[model_providers.proxy]
+name = "OpenAi"
 base_url = "${baseUrl}"
+env_key = "OPENAI_API_KEY"
 wire_api = "responses"
 supports_websockets = true
-requires_openai_auth = true
 
 [features]
 responses_websockets_v2 = true
 goals = true`
 
-  // auth.json content
-  const authContent = `{
-  "OPENAI_API_KEY": "${apiKey}"
-}`
-
   return [
     {
-      path: `${configDir}/config.toml`,
+      path: configPath,
       content: configContent,
       hint: t('keys.useKeyModal.openai.configTomlHint')
     },
     {
-      path: `${configDir}/auth.json`,
-      content: authContent
+      path: envPath,
+      content: envCommand
     }
   ]
 }
diff --git a/frontend/src/components/keys/__tests__/UseKeyModal.spec.ts b/frontend/src/components/keys/__tests__/UseKeyModal.spec.ts
index b3fdeb937ab..cc5ca4dac16 100644
--- a/frontend/src/components/keys/__tests__/UseKeyModal.spec.ts
+++ b/frontend/src/components/keys/__tests__/UseKeyModal.spec.ts
@@ -38,23 +38,57 @@ describe('UseKeyModal', () => {
     })
 
     const codeBlocks = wrapper.findAll('pre code').map((code) => code.text())
-    const configToml = codeBlocks.find((content) => content.includes('model_provider = "OpenAI"'))
+    const configToml = codeBlocks.find((content) => content.includes('model_provider = "proxy"'))
 
     expect(configToml).toBeDefined()
+    expect(configToml).toContain('preferred_auth_method = "apikey"')
     expect(configToml).toContain('model = "gpt-5.5"')
     expect(configToml).toContain('review_model = "gpt-5.5"')
+    expect(configToml).toContain('[model_providers.proxy]')
+    expect(configToml).toContain('base_url = "https://example.com/v1"')
+    expect(configToml).toContain('env_key = "OPENAI_API_KEY"')
     expect(configToml).not.toContain('model = "gpt-5.4"')
     expect(configToml).not.toContain('model_context_window')
     expect(configToml).not.toContain('model_auto_compact_token_limit')
+    expect(configToml).not.toContain('requires_openai_auth')
     expect(configToml).toContain('[features]\ngoals = true')
+
+    const envCommand = codeBlocks.find((content) => content.startsWith('export OPENAI_API_KEY'))
+    expect(envCommand).toBe('export OPENAI_API_KEY="sk-test"')
   })
 
-  it('renders GPT-5.5 and goals feature in OpenAI Codex WebSocket config', async () => {
+  it('normalizes root URLs in OpenAI Codex config', () => {
     const wrapper = mount(UseKeyModal, {
       props: {
         show: true,
         apiKey: 'sk-test',
-        baseUrl: 'https://example.com/v1',
+        baseUrl: 'https://example.com',
+        platform: 'openai'
+      },
+      global: {
+        stubs: {
+          BaseDialog: {
+            template: '<div><slot /><slot name="footer" /></div>'
+          },
+          Icon: {
+            template: '<span />'
+          }
+        }
+      }
+    })
+
+    const codeBlocks = wrapper.findAll('pre code').map((code) => code.text())
+    const configToml = codeBlocks.find((content) => content.includes('model_provider = "proxy"'))
+
+    expect(configToml).toContain('base_url = "https://example.com/v1"')
+  })
+
+  it('renders GPT-5.5 and goals feature in OpenAI Codex WebSocket config on Windows', async () => {
+    const wrapper = mount(UseKeyModal, {
+      props: {
+        show: true,
+        apiKey: 'sk-test',
+        baseUrl: 'https://example.com',
         platform: 'openai'
       },
       global: {
@@ -77,16 +111,34 @@ describe('UseKeyModal', () => {
     await wsTab!.trigger('click')
     await nextTick()
 
+    const windowsTab = wrapper.findAll('button').find((button) =>
+      button.text().includes('Windows')
+    )
+
+    expect(windowsTab).toBeDefined()
+    await windowsTab!.trigger('click')
+    await nextTick()
+
     const codeBlocks = wrapper.findAll('pre code').map((code) => code.text())
     const configToml = codeBlocks.find((content) => content.includes('supports_websockets = true'))
 
     expect(configToml).toBeDefined()
+    expect(configToml).toContain('preferred_auth_method = "apikey"')
     expect(configToml).toContain('model = "gpt-5.5"')
     expect(configToml).toContain('review_model = "gpt-5.5"')
+    expect(configToml).toContain('model_provider = "proxy"')
+    expect(configToml).toContain('[model_providers.proxy]')
+    expect(configToml).toContain('base_url = "https://example.com/v1"')
+    expect(configToml).toContain('env_key = "OPENAI_API_KEY"')
     expect(configToml).not.toContain('model = "gpt-5.4"')
     expect(configToml).not.toContain('model_context_window')
     expect(configToml).not.toContain('model_auto_compact_token_limit')
+    expect(configToml).not.toContain('requires_openai_auth')
     expect(configToml).toContain('[features]\nresponses_websockets_v2 = true\ngoals = true')
+
+    expect(wrapper.text()).toContain('%userprofile%\\.codex\\config.toml')
+    const envCommand = codeBlocks.find((content) => content.startsWith('setx OPENAI_API_KEY'))
+    expect(envCommand).toBe('setx OPENAI_API_KEY "sk-test"')
   })
 
   it('renders GPT-5.4 mini entry in OpenCode config', async () => {
@@ -119,6 +171,7 @@ describe('UseKeyModal', () => {
 
     const codeBlock = wrapper.find('pre code')
     expect(codeBlock.exists()).toBe(true)
+    expect(codeBlock.text()).toContain('"baseURL": "https://example.com/v1"')
     expect(codeBlock.text()).toContain('"name": "GPT-5.4 Mini"')
     expect(codeBlock.text()).not.toContain('"name": "GPT-5.4 Nano"')
   })
diff --git a/frontend/src/i18n/locales/en.ts b/frontend/src/i18n/locales/en.ts
index b2aeb2f83f5..ef75db12ffb 100644
--- a/frontend/src/i18n/locales/en.ts
+++ b/frontend/src/i18n/locales/en.ts
@@ -742,10 +742,10 @@ export default {
       noGroupTitle: 'Please assign a group first',
       noGroupDescription: 'This API key has not been assigned to a group. Please click the group column in the key list to assign one before viewing the configuration.',
       openai: {
-        description: 'Add the following configuration files to your Codex CLI config directory.',
+        description: 'Add config.toml to your Codex CLI config directory and set the OPENAI_API_KEY environment variable.',
         configTomlHint: 'Make sure the following content is at the beginning of the config.toml file',
-        note: 'Make sure the config directory exists. macOS/Linux users can run mkdir -p ~/.codex to create it.',
-        noteWindows: 'Press Win+R and enter %userprofile%\\.codex to open the config directory. Create it manually if it does not exist.',
+        note: 'Make sure the config directory exists. macOS/Linux users can run mkdir -p ~/.codex to create it. The environment variable command applies to the current terminal session; add it to your shell profile for a permanent setup.',
+        noteWindows: 'Press Win+R and enter %userprofile%\\.codex to open the config directory. Create it manually if it does not exist. Reopen your terminal after setting the environment variable.',
       },
       cliTabs: {
         claudeCode: 'Claude Code',
diff --git a/frontend/src/i18n/locales/zh.ts b/frontend/src/i18n/locales/zh.ts
index 85d1feee456..9a8a6cb7a0c 100644
--- a/frontend/src/i18n/locales/zh.ts
+++ b/frontend/src/i18n/locales/zh.ts
@@ -741,11 +741,11 @@ export default {
       noGroupDescription:
         '此 API 密钥尚未分配分组，请先在密钥列表中点击分组列进行分配，然后才能查看使用配置。',
       openai: {
-        description: '将以下配置文件添加到 Codex CLI 配置目录中。',
+        description: '将 config.toml 添加到 Codex CLI 配置目录，并设置 OPENAI_API_KEY 环境变量。',
         configTomlHint: '请确保以下内容位于 config.toml 文件的开头部分',
-        note: '请确保配置目录存在。macOS/Linux 用户可运行 mkdir -p ~/.codex 创建目录。',
+        note: '请确保配置目录存在。macOS/Linux 用户可运行 mkdir -p ~/.codex 创建目录。环境变量命令会在当前终端会话中生效，如需永久配置请添加到 shell 配置文件。',
         noteWindows:
-          '按 Win+R，输入 %userprofile%\\.codex 打开配置目录。如目录不存在，请先手动创建。'
+          '按 Win+R，输入 %userprofile%\\.codex 打开配置目录。如目录不存在，请先手动创建。设置环境变量后请重新打开终端。'
       },
       cliTabs: {
         claudeCode: 'Claude Code',