diff --git a/backend/internal/handler/admin/setting_handler.go b/backend/internal/handler/admin/setting_handler.go
index 9907d441..f73e4486 100644
--- a/backend/internal/handler/admin/setting_handler.go
+++ b/backend/internal/handler/admin/setting_handler.go
@@ -247,6 +247,7 @@ func (h *SettingHandler) GetSettings(c *gin.Context) {
 		EnableAnthropicCacheTTL1hInjection:     settings.EnableAnthropicCacheTTL1hInjection,
 		RewriteMessageCacheControl:             settings.RewriteMessageCacheControl,
 		AntigravityUserAgentVersion:            settings.AntigravityUserAgentVersion,
+		OpenAICodexUserAgent:                   settings.OpenAICodexUserAgent,
 		WebSearchEmulationEnabled:              settings.WebSearchEmulationEnabled,
 		PaymentVisibleMethodAlipaySource:       settings.PaymentVisibleMethodAlipaySource,
 		PaymentVisibleMethodWxpaySource:        settings.PaymentVisibleMethodWxpaySource,
@@ -563,6 +564,7 @@ type UpdateSettingsRequest struct {
 	EnableAnthropicCacheTTL1hInjection *bool   `json:"enable_anthropic_cache_ttl_1h_injection"`
 	RewriteMessageCacheControl         *bool   `json:"rewrite_message_cache_control"`
 	AntigravityUserAgentVersion        *string `json:"antigravity_user_agent_version"`
+	OpenAICodexUserAgent               *string `json:"openai_codex_user_agent"`
 
 	// Payment visible method routing
 	PaymentVisibleMethodAlipaySource  *string `json:"payment_visible_method_alipay_source"`
@@ -1404,6 +1406,15 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 			return
 		}
 	}
+	if req.OpenAICodexUserAgent != nil {
+		normalized := strings.TrimSpace(*req.OpenAICodexUserAgent)
+		req.OpenAICodexUserAgent = &normalized
+		// 仅做长度上限保护，不限制具体格式（运维需要可自由调整 codex 版本号）
+		if len(normalized) > 512 {
+			response.Error(c, http.StatusBadRequest, "openai_codex_user_agent must be at most 512 characters")
+			return
+		}
+	}
 
 	// 交叉验证：如果同时设置了最低和最高版本号，最高版本号必须 >= 最低版本号
 	if req.MinClaudeCodeVersion != "" && req.MaxClaudeCodeVersion != "" {
@@ -1597,6 +1608,12 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 			}
 			return previousSettings.AntigravityUserAgentVersion
 		}(),
+		OpenAICodexUserAgent: func() string {
+			if req.OpenAICodexUserAgent != nil {
+				return *req.OpenAICodexUserAgent
+			}
+			return previousSettings.OpenAICodexUserAgent
+		}(),
 		PaymentVisibleMethodAlipaySource: func() string {
 			if req.PaymentVisibleMethodAlipaySource != nil {
 				return strings.TrimSpace(*req.PaymentVisibleMethodAlipaySource)
@@ -1956,6 +1973,7 @@ func (h *SettingHandler) UpdateSettings(c *gin.Context) {
 		EnableAnthropicCacheTTL1hInjection:     updatedSettings.EnableAnthropicCacheTTL1hInjection,
 		RewriteMessageCacheControl:             updatedSettings.RewriteMessageCacheControl,
 		AntigravityUserAgentVersion:            updatedSettings.AntigravityUserAgentVersion,
+		OpenAICodexUserAgent:                   updatedSettings.OpenAICodexUserAgent,
 		PaymentVisibleMethodAlipaySource:       updatedSettings.PaymentVisibleMethodAlipaySource,
 		PaymentVisibleMethodWxpaySource:        updatedSettings.PaymentVisibleMethodWxpaySource,
 		PaymentVisibleMethodAlipayEnabled:      updatedSettings.PaymentVisibleMethodAlipayEnabled,
@@ -2411,6 +2429,9 @@ func diffSettings(before *service.SystemSettings, after *service.SystemSettings,
 	if before.AntigravityUserAgentVersion != after.AntigravityUserAgentVersion {
 		changed = append(changed, "antigravity_user_agent_version")
 	}
+	if before.OpenAICodexUserAgent != after.OpenAICodexUserAgent {
+		changed = append(changed, "openai_codex_user_agent")
+	}
 	if before.PaymentVisibleMethodAlipaySource != after.PaymentVisibleMethodAlipaySource {
 		changed = append(changed, "payment_visible_method_alipay_source")
 	}
diff --git a/backend/internal/handler/dto/settings.go b/backend/internal/handler/dto/settings.go
index 45ad7a70..fd3a90b3 100644
--- a/backend/internal/handler/dto/settings.go
+++ b/backend/internal/handler/dto/settings.go
@@ -181,6 +181,7 @@ type SystemSettings struct {
 	EnableAnthropicCacheTTL1hInjection bool   `json:"enable_anthropic_cache_ttl_1h_injection"`
 	RewriteMessageCacheControl         bool   `json:"rewrite_message_cache_control"`
 	AntigravityUserAgentVersion        string `json:"antigravity_user_agent_version"`
+	OpenAICodexUserAgent               string `json:"openai_codex_user_agent"`
 
 	// Web Search Emulation
 	WebSearchEmulationEnabled bool `json:"web_search_emulation_enabled"`
diff --git a/backend/internal/pkg/openai/request.go b/backend/internal/pkg/openai/request.go
index dd8fe566..ae3886d6 100644
--- a/backend/internal/pkg/openai/request.go
+++ b/backend/internal/pkg/openai/request.go
@@ -30,6 +30,17 @@ var CodexOfficialClientOriginatorPrefixes = []string{
 	"codex ",
 }
 
+// IsBrowserUserAgent 判断 User-Agent 是否来自浏览器（Chrome/Firefox/Safari/Edge/Opera 等）。
+// 所有现代浏览器的 UA 均以 "Mozilla/" 作为前缀，CLI 工具（codex/claude/curl/postman/python-requests 等）不会。
+// 该判定用于避免 Cloudflare 对浏览器型 UA 在 OpenAI 上游接口上触发 JS 质询。
+func IsBrowserUserAgent(userAgent string) bool {
+	ua := strings.TrimSpace(userAgent)
+	if ua == "" {
+		return false
+	}
+	return strings.HasPrefix(strings.ToLower(ua), "mozilla/")
+}
+
 // IsCodexCLIRequest checks if the User-Agent indicates a Codex CLI request
 func IsCodexCLIRequest(userAgent string) bool {
 	ua := normalizeCodexClientHeader(userAgent)
diff --git a/backend/internal/service/domain_constants.go b/backend/internal/service/domain_constants.go
index f39c5d7e..e697f459 100644
--- a/backend/internal/service/domain_constants.go
+++ b/backend/internal/service/domain_constants.go
@@ -400,6 +400,10 @@ const (
 	SettingKeyRewriteMessageCacheControl = "rewrite_message_cache_control"
 	// SettingKeyAntigravityUserAgentVersion Antigravity 上游 User-Agent 版本号（空值使用环境变量/默认值）
 	SettingKeyAntigravityUserAgentVersion = "antigravity_user_agent_version"
+	// SettingKeyOpenAICodexUserAgent OpenAI Codex 完整 User-Agent（空值使用内置默认）
+	// 当客户端 UA 被识别为浏览器（Chrome/Firefox/Safari/Edge 等）时，转发给 OpenAI 上游前会替换为此值，
+	// 用于避免 Cloudflare 对浏览器型 UA 的质询拦截。
+	SettingKeyOpenAICodexUserAgent = "openai_codex_user_agent"
 
 	// Balance Low Notification
 	SettingKeyBalanceLowNotifyEnabled     = "balance_low_notify_enabled"      // 全局开关
diff --git a/backend/internal/service/openai_gateway_service.go b/backend/internal/service/openai_gateway_service.go
index cfaf5bff..bf3318a3 100644
--- a/backend/internal/service/openai_gateway_service.go
+++ b/backend/internal/service/openai_gateway_service.go
@@ -3231,6 +3231,10 @@ func (s *OpenAIGatewayService) buildUpstreamRequestOpenAIPassthrough(
 		req.Header.Set("user-agent", codexCLIUserAgent)
 	}
 
+	// 浏览器型 UA 兜底：仅 OAuth（ChatGPT 内部接口）账号生效，若最终 user-agent 仍为浏览器
+	// （Chrome/Firefox/Safari/Edge 等），替换为后台配置的 Codex UA，避免 Cloudflare 触发 JS 质询。
+	s.overrideBrowserUserAgent(ctx, account, req)
+
 	if req.Header.Get("content-type") == "" {
 		req.Header.Set("content-type", "application/json")
 	}
@@ -3947,6 +3951,10 @@ func (s *OpenAIGatewayService) buildUpstreamRequest(ctx context.Context, c *gin.
 		req.Header.Set("user-agent", codexCLIUserAgent)
 	}
 
+	// 浏览器型 UA 兜底：仅 OAuth（ChatGPT 内部接口）账号生效，若最终 user-agent 仍为浏览器
+	// （Chrome/Firefox/Safari/Edge 等），替换为后台配置的 Codex UA，避免 Cloudflare 触发 JS 质询。
+	s.overrideBrowserUserAgent(ctx, account, req)
+
 	// Ensure required headers exist
 	if req.Header.Get("content-type") == "" {
 		req.Header.Set("content-type", "application/json")
@@ -3955,6 +3963,30 @@ func (s *OpenAIGatewayService) buildUpstreamRequest(ctx context.Context, c *gin.
 	return req, nil
 }
 
+// overrideBrowserUserAgent 检查请求的最终 user-agent，若为浏览器 UA 则替换为后台配置的 Codex UA。
+// 用于规避 Cloudflare 对浏览器型 UA 在 ChatGPT 内部接口上的访问质询。
+// 影响范围严格限定：仅 OAuth（Codex/ChatGPT 内部接口）账号生效；API Key 等其他账号原样透传。
+// 仅在识别为浏览器（Mozilla/...）时改写，其他 CLI/工具 UA 不动。
+func (s *OpenAIGatewayService) overrideBrowserUserAgent(ctx context.Context, account *Account, req *http.Request) {
+	if req == nil || account == nil {
+		return
+	}
+	if account.Type != AccountTypeOAuth {
+		return
+	}
+	currentUA := req.Header.Get("user-agent")
+	if !openai.IsBrowserUserAgent(currentUA) {
+		return
+	}
+	codexUA := DefaultOpenAICodexUserAgent
+	if s != nil && s.settingService != nil {
+		if v := strings.TrimSpace(s.settingService.GetOpenAICodexUserAgent(ctx)); v != "" {
+			codexUA = v
+		}
+	}
+	req.Header.Set("user-agent", codexUA)
+}
+
 func (s *OpenAIGatewayService) handleErrorResponse(
 	ctx context.Context,
 	resp *http.Response,
diff --git a/backend/internal/service/setting_service.go b/backend/internal/service/setting_service.go
index a5c16b1f..bd99e341 100644
--- a/backend/internal/service/setting_service.go
+++ b/backend/internal/service/setting_service.go
@@ -128,6 +128,19 @@ const antigravityUserAgentVersionCacheTTL = 60 * time.Second
 const antigravityUserAgentVersionErrorTTL = 5 * time.Second
 const antigravityUserAgentVersionDBTimeout = 5 * time.Second
 
+// DefaultOpenAICodexUserAgent OpenAI Codex 默认 User-Agent（用于规避 Cloudflare 对浏览器 UA 的质询）
+const DefaultOpenAICodexUserAgent = "codex-tui/0.125.0 (Ubuntu 22.4.0; x86_64) xterm-256color (codex-tui; 0.125.0)"
+
+// cachedOpenAICodexUserAgent 缓存 OpenAI Codex UA（进程内缓存，60s TTL）
+type cachedOpenAICodexUserAgent struct {
+	value     string
+	expiresAt int64 // unix nano
+}
+
+const openAICodexUserAgentCacheTTL = 60 * time.Second
+const openAICodexUserAgentErrorTTL = 5 * time.Second
+const openAICodexUserAgentDBTimeout = 5 * time.Second
+
 // DefaultSubscriptionGroupReader validates group references used by default subscriptions.
 type DefaultSubscriptionGroupReader interface {
 	GetByID(ctx context.Context, id int64) (*Group, error)
@@ -148,6 +161,8 @@ type SettingService struct {
 	webSearchManagerBuilder   WebSearchManagerBuilder
 	antigravityUAVersionCache atomic.Value // *cachedAntigravityUserAgentVersion
 	antigravityUAVersionSF    singleflight.Group
+	openAICodexUACache        atomic.Value // *cachedOpenAICodexUserAgent
+	openAICodexUASF           singleflight.Group
 }
 
 type ProviderDefaultGrantSettings struct {
@@ -907,6 +922,55 @@ func (s *SettingService) GetAntigravityUserAgentVersion(ctx context.Context) str
 	return fallback
 }
 
+// GetOpenAICodexUserAgent 返回 OpenAI Codex 上游请求使用的 User-Agent。
+// 后台设置优先；为空时回退到内置默认值。
+func (s *SettingService) GetOpenAICodexUserAgent(ctx context.Context) string {
+	fallback := DefaultOpenAICodexUserAgent
+	if s == nil || s.settingRepo == nil {
+		return fallback
+	}
+	if cached, ok := s.openAICodexUACache.Load().(*cachedOpenAICodexUserAgent); ok && cached != nil {
+		if time.Now().UnixNano() < cached.expiresAt {
+			return cached.value
+		}
+	}
+
+	result, _, _ := s.openAICodexUASF.Do("openai_codex_user_agent", func() (any, error) {
+		if cached, ok := s.openAICodexUACache.Load().(*cachedOpenAICodexUserAgent); ok && cached != nil {
+			if time.Now().UnixNano() < cached.expiresAt {
+				return cached.value, nil
+			}
+		}
+		if ctx == nil {
+			ctx = context.Background()
+		}
+		dbCtx, cancel := context.WithTimeout(context.WithoutCancel(ctx), openAICodexUserAgentDBTimeout)
+		defer cancel()
+		value, err := s.settingRepo.GetValue(dbCtx, SettingKeyOpenAICodexUserAgent)
+		if err != nil && !errors.Is(err, ErrSettingNotFound) {
+			slog.Warn("failed to get openai codex user agent setting", "error", err)
+			s.openAICodexUACache.Store(&cachedOpenAICodexUserAgent{
+				value:     fallback,
+				expiresAt: time.Now().Add(openAICodexUserAgentErrorTTL).UnixNano(),
+			})
+			return fallback, nil
+		}
+		ua := strings.TrimSpace(value)
+		if ua == "" {
+			ua = fallback
+		}
+		s.openAICodexUACache.Store(&cachedOpenAICodexUserAgent{
+			value:     ua,
+			expiresAt: time.Now().Add(openAICodexUserAgentCacheTTL).UnixNano(),
+		})
+		return ua, nil
+	})
+	if ua, ok := result.(string); ok && ua != "" {
+		return ua
+	}
+	return fallback
+}
+
 // SetOnUpdateCallback sets a callback function to be called when settings are updated
 // This is used for cache invalidation (e.g., HTML cache in frontend server)
 func (s *SettingService) SetOnUpdateCallback(callback func()) {
@@ -1706,6 +1770,7 @@ func (s *SettingService) buildSystemSettingsUpdates(ctx context.Context, setting
 	updates[SettingKeyEnableAnthropicCacheTTL1hInjection] = strconv.FormatBool(settings.EnableAnthropicCacheTTL1hInjection)
 	updates[SettingKeyRewriteMessageCacheControl] = strconv.FormatBool(settings.RewriteMessageCacheControl)
 	updates[SettingKeyAntigravityUserAgentVersion] = antigravity.NormalizeUserAgentVersion(settings.AntigravityUserAgentVersion)
+	updates[SettingKeyOpenAICodexUserAgent] = strings.TrimSpace(settings.OpenAICodexUserAgent)
 	updates[SettingPaymentVisibleMethodAlipaySource] = settings.PaymentVisibleMethodAlipaySource
 	updates[SettingPaymentVisibleMethodWxpaySource] = settings.PaymentVisibleMethodWxpaySource
 	updates[SettingPaymentVisibleMethodAlipayEnabled] = strconv.FormatBool(settings.PaymentVisibleMethodAlipayEnabled)
@@ -1788,6 +1853,15 @@ func (s *SettingService) refreshCachedSettings(settings *SystemSettings) {
 		version:   antigravityUserAgentVersion,
 		expiresAt: time.Now().Add(antigravityUserAgentVersionCacheTTL).UnixNano(),
 	})
+	s.openAICodexUASF.Forget("openai_codex_user_agent")
+	codexUA := strings.TrimSpace(settings.OpenAICodexUserAgent)
+	if codexUA == "" {
+		codexUA = DefaultOpenAICodexUserAgent
+	}
+	s.openAICodexUACache.Store(&cachedOpenAICodexUserAgent{
+		value:     codexUA,
+		expiresAt: time.Now().Add(openAICodexUserAgentCacheTTL).UnixNano(),
+	})
 	openAIAdvancedSchedulerSettingSF.Forget(openAIAdvancedSchedulerSettingKey)
 	openAIAdvancedSchedulerSettingCache.Store(&cachedOpenAIAdvancedSchedulerSetting{
 		enabled:   settings.OpenAIAdvancedSchedulerEnabled,
@@ -2529,6 +2603,7 @@ func (s *SettingService) InitializeDefaultSettings(ctx context.Context) error {
 		SettingKeyEnableAnthropicCacheTTL1hInjection: "false",
 		SettingKeyRewriteMessageCacheControl:         strconv.FormatBool(s.defaultRewriteMessageCacheControl()),
 		SettingKeyAntigravityUserAgentVersion:        "",
+		SettingKeyOpenAICodexUserAgent:               "",
 		SettingPaymentVisibleMethodAlipaySource:      "",
 		SettingPaymentVisibleMethodWxpaySource:       "",
 		SettingPaymentVisibleMethodAlipayEnabled:     "false",
@@ -3041,6 +3116,7 @@ func (s *SettingService) parseSettings(settings map[string]string) *SystemSettin
 		result.RewriteMessageCacheControl = s.defaultRewriteMessageCacheControl()
 	}
 	result.AntigravityUserAgentVersion = antigravity.NormalizeUserAgentVersion(settings[SettingKeyAntigravityUserAgentVersion])
+	result.OpenAICodexUserAgent = strings.TrimSpace(settings[SettingKeyOpenAICodexUserAgent])
 
 	// Web search emulation: quick enabled check from the JSON config
 	if raw := settings[SettingKeyWebSearchEmulationConfig]; raw != "" {
diff --git a/backend/internal/service/settings_view.go b/backend/internal/service/settings_view.go
index ea5fa57c..1e5e8b1c 100644
--- a/backend/internal/service/settings_view.go
+++ b/backend/internal/service/settings_view.go
@@ -193,6 +193,7 @@ type SystemSettings struct {
 	EnableAnthropicCacheTTL1hInjection bool   // 是否对 Anthropic OAuth/SetupToken 请求体注入 1h cache_control ttl（默认 false）
 	RewriteMessageCacheControl         bool   // 是否改写 messages[*].content[*].cache_control（默认 false）
 	AntigravityUserAgentVersion        string // Antigravity 上游 User-Agent 版本号；空值使用配置/默认值
+	OpenAICodexUserAgent               string // OpenAI Codex 上游完整 User-Agent；空值使用内置默认
 
 	// Web Search Emulation
 	WebSearchEmulationEnabled bool // 是否启用 web search 模拟
diff --git a/frontend/src/api/admin/settings.ts b/frontend/src/api/admin/settings.ts
index dfef451d..fd9e2b8d 100644
--- a/frontend/src/api/admin/settings.ts
+++ b/frontend/src/api/admin/settings.ts
@@ -504,6 +504,7 @@ export interface SystemSettings {
   enable_anthropic_cache_ttl_1h_injection: boolean;
   rewrite_message_cache_control: boolean;
   antigravity_user_agent_version: string;
+  openai_codex_user_agent: string;
   web_search_emulation_enabled?: boolean;
 
   // Payment configuration
@@ -724,6 +725,7 @@ export interface UpdateSettingsRequest {
   enable_anthropic_cache_ttl_1h_injection?: boolean;
   rewrite_message_cache_control?: boolean;
   antigravity_user_agent_version?: string;
+  openai_codex_user_agent?: string;
   // Payment configuration
   payment_enabled?: boolean;
   risk_control_enabled?: boolean;
diff --git a/frontend/src/i18n/locales/en.ts b/frontend/src/i18n/locales/en.ts
index 9ac1466e..70f7724c 100644
--- a/frontend/src/i18n/locales/en.ts
+++ b/frontend/src/i18n/locales/en.ts
@@ -5454,6 +5454,9 @@ export default {
         antigravityUserAgentVersion: 'Antigravity UA Version',
         antigravityUserAgentVersionPlaceholder: '1.23.2',
         antigravityUserAgentVersionHint: 'Leave empty to use ANTIGRAVITY_USER_AGENT_VERSION or the built-in default 1.23.2; when set, the admin setting takes precedence.',
+        openaiCodexUserAgent: 'OpenAI Codex UA',
+        openaiCodexUserAgentPlaceholder: 'codex-tui/0.125.0 (Ubuntu 22.4.0; x86_64) xterm-256color (codex-tui; 0.125.0)',
+        openaiCodexUserAgentHint: 'Used to bypass Cloudflare browser-UA challenges on the OpenAI upstream. Only applies when the client User-Agent is detected as a browser (Mozilla/...). Leave empty to use the built-in default.',
       },
       webSearchEmulation: {
         title: 'Web Search Emulation',
diff --git a/frontend/src/i18n/locales/zh.ts b/frontend/src/i18n/locales/zh.ts
index 3e90405a..3a9a64ff 100644
--- a/frontend/src/i18n/locales/zh.ts
+++ b/frontend/src/i18n/locales/zh.ts
@@ -5612,6 +5612,9 @@ export default {
         antigravityUserAgentVersion: 'Antigravity UA 版本',
         antigravityUserAgentVersionPlaceholder: '1.23.2',
         antigravityUserAgentVersionHint: '留空时使用 ANTIGRAVITY_USER_AGENT_VERSION 或内置默认值 1.23.2；填写后后台设置优先。',
+        openaiCodexUserAgent: 'OpenAI Codex UA',
+        openaiCodexUserAgentPlaceholder: 'codex-tui/0.125.0 (Ubuntu 22.4.0; x86_64) xterm-256color (codex-tui; 0.125.0)',
+        openaiCodexUserAgentHint: '用于规避 OpenAI 上游 Cloudflare 对浏览器 UA 的访问质询。仅在检测到客户端 User-Agent 为浏览器（Mozilla/...）时生效，其他客户端原样透传。留空使用内置默认值。',
       },
       webSearchEmulation: {
         title: 'Web Search 模拟',
diff --git a/frontend/src/views/admin/SettingsView.vue b/frontend/src/views/admin/SettingsView.vue
index e0c3e1d4..118dd1a9 100644
--- a/frontend/src/views/admin/SettingsView.vue
+++ b/frontend/src/views/admin/SettingsView.vue
@@ -3769,6 +3769,36 @@
                   }}
                 </p>
               </div>
+
+              <!-- OpenAI Codex UA -->
+              <div>
+                <label
+                  class="mb-2 block text-sm font-medium text-gray-700 dark:text-gray-300"
+                >
+                  {{
+                    t(
+                      "admin.settings.gatewayForwarding.openaiCodexUserAgent",
+                    )
+                  }}
+                </label>
+                <input
+                  v-model="form.openai_codex_user_agent"
+                  type="text"
+                  class="input w-full font-mono text-sm"
+                  :placeholder="
+                    t(
+                      'admin.settings.gatewayForwarding.openaiCodexUserAgentPlaceholder',
+                    )
+                  "
+                />
+                <p class="mt-1.5 text-xs text-gray-500 dark:text-gray-400">
+                  {{
+                    t(
+                      "admin.settings.gatewayForwarding.openaiCodexUserAgentHint",
+                    )
+                  }}
+                </p>
+              </div>
             </div>
           </div>
           <!-- Web Search Emulation -->
@@ -6942,6 +6972,7 @@ const form = reactive<SettingsForm>({
   enable_anthropic_cache_ttl_1h_injection: false,
   rewrite_message_cache_control: false,
   antigravity_user_agent_version: "",
+  openai_codex_user_agent: "",
   // Balance & quota notification
   balance_low_notify_enabled: false,
   balance_low_notify_threshold: 0,
@@ -8042,6 +8073,8 @@ async function saveSettings() {
       rewrite_message_cache_control: form.rewrite_message_cache_control,
       antigravity_user_agent_version:
         form.antigravity_user_agent_version?.trim() || "",
+      openai_codex_user_agent:
+        form.openai_codex_user_agent?.trim() || "",
       // Payment configuration
       payment_enabled: form.payment_enabled,
       risk_control_enabled: form.risk_control_enabled,
diff --git a/frontend/src/views/admin/__tests__/SettingsView.spec.ts b/frontend/src/views/admin/__tests__/SettingsView.spec.ts
index 275e38c5..0d4ab7d2 100644
--- a/frontend/src/views/admin/__tests__/SettingsView.spec.ts
+++ b/frontend/src/views/admin/__tests__/SettingsView.spec.ts
@@ -371,6 +371,7 @@ const baseSettingsResponse = {
   enable_anthropic_cache_ttl_1h_injection: false,
   rewrite_message_cache_control: false,
   antigravity_user_agent_version: "",
+  openai_codex_user_agent: "",
   payment_enabled: true,
   payment_min_amount: 1,
   payment_max_amount: 10000,