Wei-Shaw · Wei-Shaw · Jun 1, 2026 · Jun 1, 2026
diff --git a/backend/internal/handler/admin/user_handler.go b/backend/internal/handler/admin/user_handler.go
@@ -34,14 +34,14 @@ func NewUserHandler(adminService service.AdminService, concurrencyService *servi
 
 // CreateUserRequest represents admin create user request
 type CreateUserRequest struct {
-	Email         string  `json:"email" binding:"required,email"`
-	Password      string  `json:"password" binding:"required,min=6"`
-	Username      string  `json:"username"`
-	Notes         string  `json:"notes"`
-	Balance       float64 `json:"balance"`
-	Concurrency   int     `json:"concurrency"`
-	RPMLimit      int     `json:"rpm_limit"`
-	AllowedGroups []int64 `json:"allowed_groups"`
+	Email         string   `json:"email" binding:"required,email"`
+	Password      string   `json:"password" binding:"required,min=6"`
+	Username      string   `json:"username"`
+	Notes         string   `json:"notes"`
+	Balance       *float64 `json:"balance"`
+	Concurrency   int      `json:"concurrency"`
+	RPMLimit      int      `json:"rpm_limit"`
+	AllowedGroups []int64  `json:"allowed_groups"`
 }
 
 // UpdateUserRequest represents admin update user request

diff --git a/backend/internal/service/admin_service.go b/backend/internal/service/admin_service.go
@@ -120,7 +120,7 @@ type CreateUserInput struct {
 	Password      string
 	Username      string
 	Notes         string
-	Balance       float64
+	Balance       *float64
 	Concurrency   int
 	RPMLimit      int
 	AllowedGroups []int64
@@ -661,12 +661,19 @@ func (s *adminServiceImpl) GetUser(ctx context.Context, id int64) (*User, error)
 }
 
 func (s *adminServiceImpl) CreateUser(ctx context.Context, input *CreateUserInput) (*User, error) {
+	balance := 0.0
+	if input.Balance != nil {
+		balance = *input.Balance
+	} else if s.settingService != nil {
+		balance = s.settingService.GetDefaultBalance(ctx)
+	}
+
 	user := &User{
 		Email:         input.Email,
 		Username:      input.Username,
 		Notes:         input.Notes,
 		Role:          RoleUser, // Always create as regular user, never admin
-		Balance:       input.Balance,
+		Balance:       balance,
 		Concurrency:   input.Concurrency,
 		RPMLimit:      input.RPMLimit,
 		Status:        StatusActive,

diff --git a/backend/internal/service/admin_service_create_user_test.go b/backend/internal/service/admin_service_create_user_test.go
@@ -14,13 +14,14 @@ import (
 func TestAdminService_CreateUser_Success(t *testing.T) {
 	repo := &userRepoStub{nextID: 10}
 	svc := &adminServiceImpl{userRepo: repo}
+	balance := 12.5
 
 	input := &CreateUserInput{
 		Email:         "user@test.com",
 		Password:      "strong-pass",
 		Username:      "tester",
 		Notes:         "note",
-		Balance:       12.5,
+		Balance:       &balance,
 		Concurrency:   7,
 		AllowedGroups: []int64{3, 5},
 	}
@@ -32,7 +33,7 @@ func TestAdminService_CreateUser_Success(t *testing.T) {
 	require.Equal(t, input.Email, user.Email)
 	require.Equal(t, input.Username, user.Username)
 	require.Equal(t, input.Notes, user.Notes)
-	require.Equal(t, input.Balance, user.Balance)
+	require.Equal(t, balance, user.Balance)
 	require.Equal(t, input.Concurrency, user.Concurrency)
 	require.Equal(t, input.AllowedGroups, user.AllowedGroups)
 	require.Equal(t, RoleUser, user.Role)
@@ -42,6 +43,56 @@ func TestAdminService_CreateUser_Success(t *testing.T) {
 	require.Equal(t, user, repo.created[0])
 }
 
+func TestAdminService_CreateUser_UsesDefaultBalanceWhenBalanceOmitted(t *testing.T) {
+	repo := &userRepoStub{nextID: 11}
+	cfg := &config.Config{
+		Default: config.DefaultConfig{
+			UserBalance: 0,
+		},
+	}
+	settingService := NewSettingService(&settingRepoStub{values: map[string]string{
+		SettingKeyDefaultBalance: "0.02",
+	}}, cfg)
+	svc := &adminServiceImpl{userRepo: repo, settingService: settingService}
+
+	user, err := svc.CreateUser(context.Background(), &CreateUserInput{
+		Email:    "default-balance@test.com",
+		Password: "strong-pass",
+	})
+
+	require.NoError(t, err)
+	require.NotNil(t, user)
+	require.Equal(t, 0.02, user.Balance)
+	require.Len(t, repo.created, 1)
+	require.Equal(t, 0.02, repo.created[0].Balance)
+}
+
+func TestAdminService_CreateUser_ExplicitZeroBalanceOverridesDefault(t *testing.T) {
+	repo := &userRepoStub{nextID: 12}
+	cfg := &config.Config{
+		Default: config.DefaultConfig{
+			UserBalance: 0,
+		},
+	}
+	settingService := NewSettingService(&settingRepoStub{values: map[string]string{
+		SettingKeyDefaultBalance: "0.02",
+	}}, cfg)
+	svc := &adminServiceImpl{userRepo: repo, settingService: settingService}
+	balance := 0.0
+
+	user, err := svc.CreateUser(context.Background(), &CreateUserInput{
+		Email:    "zero-balance@test.com",
+		Password: "strong-pass",
+		Balance:  &balance,
+	})
+
+	require.NoError(t, err)
+	require.NotNil(t, user)
+	require.Equal(t, 0.0, user.Balance)
+	require.Len(t, repo.created, 1)
+	require.Equal(t, 0.0, repo.created[0].Balance)
+}
+
 func TestAdminService_CreateUser_EmailExists(t *testing.T) {
 	repo := &userRepoStub{createErr: ErrEmailExists}
 	svc := &adminServiceImpl{userRepo: repo}

diff --git a/frontend/src/api/admin/users.ts b/frontend/src/api/admin/users.ts
@@ -115,8 +115,11 @@ export async function getById(id: number): Promise<AdminUser> {
 export async function create(userData: {
   email: string
   password: string
+  username?: string
+  notes?: string
   balance?: number
   concurrency?: number
+  rpm_limit?: number
   allowed_groups?: number[] | null
 }): Promise<AdminUser> {
   const { data } = await apiClient.post<AdminUser>('/admin/users', userData)

diff --git a/frontend/src/components/admin/user/UserCreateModal.vue b/frontend/src/components/admin/user/UserCreateModal.vue
@@ -28,7 +28,7 @@
       <div class="grid grid-cols-1 sm:grid-cols-2 gap-4">
         <div>
           <label class="input-label">{{ t('admin.users.columns.balance') }}</label>
-          <input v-model.number="form.balance" type="number" step="any" class="input" />
+          <input v-model="form.balance" type="number" step="any" class="input" />
         </div>
         <div>
           <label class="input-label">{{ t('admin.users.columns.concurrency') }}</label>
@@ -69,18 +69,24 @@ import Icon from '@/components/icons/Icon.vue'
 const props = defineProps<{ show: boolean }>()
 const emit = defineEmits(['close', 'success']); const { t } = useI18n()
 
-const form = reactive({ email: '', password: '', username: '', notes: '', balance: 0, concurrency: 1, rpm_limit: 0 })
+const form = reactive({ email: '', password: '', username: '', notes: '', balance: '', concurrency: 1, rpm_limit: 0 })
 
 const { loading, submit } = useForm({
   form,
   submitFn: async (data) => {
-    await adminAPI.users.create(data)
+    const { balance: rawBalance, ...rest } = data
+    const balance = String(rawBalance).trim()
+    const payload: typeof rest & { balance?: number } = { ...rest }
+    if (balance !== '') {
+      payload.balance = Number(balance)
+    }
+    await adminAPI.users.create(payload)
     emit('success'); emit('close')
   },
   successMsg: t('admin.users.userCreated')
 })
 
-watch(() => props.show, (v) => { if(v) Object.assign(form, { email: '', password: '', username: '', notes: '', balance: 0, concurrency: 1, rpm_limit: 0 }) })
+watch(() => props.show, (v) => { if(v) Object.assign(form, { email: '', password: '', username: '', notes: '', balance: '', concurrency: 1, rpm_limit: 0 }) })
 
 const generateRandomPassword = () => {
   const chars = 'ABCDEFGHJKLMNPQRSTUVWXYZabcdefghjkmnpqrstuvwxyz23456789!@#$%^&*'