Merge PR #213: feat(openai): 支持 OpenAI Responses API 标准内容格式

* fix(auth): 修复 RefreshToken 使用过期 token 时的 nil pointer panic

问题分析：
- RefreshToken 允许过期 token 继续流程（用于无感刷新）
- 但 ValidateToken 在 token 过期时返回 nil claims
- 导致后续访问 claims.UserID 时触发 panic

修复方案：
- 修改 ValidateToken，在检测到 ErrTokenExpired 时仍然返回 claims
- jwt-go 在解析时即使遇到过期错误，token.Claims 仍会被填充
- 这样 RefreshToken 可以正常获取用户信息并生成新 token

新增测试：
- TestAuthService_ValidateToken_ExpiredReturnsClaimsWithError
- TestAuthService_RefreshToken_ExpiredTokenNoPanic

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(auth): 修复邮件验证服务未配置时可绕过验证的安全漏洞

当邮件验证开启但 emailService 未配置时，原逻辑允许用户绕过验证直接注册。
现在会返回 ErrServiceUnavailable 拒绝注册，确保配置错误不会导致安全问题。

- 在验证码检查前先检查 emailService 是否配置
- 添加日志记录帮助发现配置问题
- 新增单元测试覆盖该场景

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: yangjianbo <yangjianbo@leagsoft.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

backend/ent/group.go

@@ -51,6 +51,10 @@ type Group struct {
 	ImagePrice2k *float64 `json:"image_price_2k,omitempty"`
 	// ImagePrice4k holds the value of the "image_price_4k" field.
 	ImagePrice4k *float64 `json:"image_price_4k,omitempty"`
+	// 是否仅允许 Claude Code 客户端
+	ClaudeCodeOnly bool `json:"claude_code_only,omitempty"`
+	// 非 Claude Code 请求降级使用的分组 ID
+	FallbackGroupID *int64 `json:"fallback_group_id,omitempty"`
 	// Edges holds the relations/edges for other nodes in the graph.
 	// The values are being populated by the GroupQuery when eager-loading is set.
 	Edges        GroupEdges `json:"edges"`
@@ -157,11 +161,11 @@ func (*Group) scanValues(columns []string) ([]any, error) {
 	values := make([]any, len(columns))
 	for i := range columns {
 		switch columns[i] {
-		case group.FieldIsExclusive:
+		case group.FieldIsExclusive, group.FieldClaudeCodeOnly:
 			values[i] = new(sql.NullBool)
 		case group.FieldRateMultiplier, group.FieldDailyLimitUsd, group.FieldWeeklyLimitUsd, group.FieldMonthlyLimitUsd, group.FieldImagePrice1k, group.FieldImagePrice2k, group.FieldImagePrice4k:
 			values[i] = new(sql.NullFloat64)
-		case group.FieldID, group.FieldDefaultValidityDays:
+		case group.FieldID, group.FieldDefaultValidityDays, group.FieldFallbackGroupID:
 			values[i] = new(sql.NullInt64)
 		case group.FieldName, group.FieldDescription, group.FieldStatus, group.FieldPlatform, group.FieldSubscriptionType:
 			values[i] = new(sql.NullString)
@@ -298,6 +302,19 @@ func (_m *Group) assignValues(columns []string, values []any) error {
 				_m.ImagePrice4k = new(float64)
 				*_m.ImagePrice4k = value.Float64
 			}
+		case group.FieldClaudeCodeOnly:
+			if value, ok := values[i].(*sql.NullBool); !ok {
+				return fmt.Errorf("unexpected type %T for field claude_code_only", values[i])
+			} else if value.Valid {
+				_m.ClaudeCodeOnly = value.Bool
+			}
+		case group.FieldFallbackGroupID:
+			if value, ok := values[i].(*sql.NullInt64); !ok {
+				return fmt.Errorf("unexpected type %T for field fallback_group_id", values[i])
+			} else if value.Valid {
+				_m.FallbackGroupID = new(int64)
+				*_m.FallbackGroupID = value.Int64
+			}
 		default:
 			_m.selectValues.Set(columns[i], values[i])
 		}
@@ -440,6 +457,14 @@ func (_m *Group) String() string {
 		builder.WriteString("image_price_4k=")
 		builder.WriteString(fmt.Sprintf("%v", *v))
 	}
+	builder.WriteString(", ")
+	builder.WriteString("claude_code_only=")
+	builder.WriteString(fmt.Sprintf("%v", _m.ClaudeCodeOnly))
+	builder.WriteString(", ")
+	if v := _m.FallbackGroupID; v != nil {
+		builder.WriteString("fallback_group_id=")
+		builder.WriteString(fmt.Sprintf("%v", *v))
+	}
 	builder.WriteByte(')')
 	return builder.String()
 }

backend/ent/group/group.go

@@ -49,6 +49,10 @@ const (
 	FieldImagePrice2k = "image_price_2k"
 	// FieldImagePrice4k holds the string denoting the image_price_4k field in the database.
 	FieldImagePrice4k = "image_price_4k"
+	// FieldClaudeCodeOnly holds the string denoting the claude_code_only field in the database.
+	FieldClaudeCodeOnly = "claude_code_only"
+	// FieldFallbackGroupID holds the string denoting the fallback_group_id field in the database.
+	FieldFallbackGroupID = "fallback_group_id"
 	// EdgeAPIKeys holds the string denoting the api_keys edge name in mutations.
 	EdgeAPIKeys = "api_keys"
 	// EdgeRedeemCodes holds the string denoting the redeem_codes edge name in mutations.
@@ -141,6 +145,8 @@ var Columns = []string{
 	FieldImagePrice1k,
 	FieldImagePrice2k,
 	FieldImagePrice4k,
+	FieldClaudeCodeOnly,
+	FieldFallbackGroupID,
 }
 
 var (
@@ -196,6 +202,8 @@ var (
 	SubscriptionTypeValidator func(string) error
 	// DefaultDefaultValidityDays holds the default value on creation for the "default_validity_days" field.
 	DefaultDefaultValidityDays int
+	// DefaultClaudeCodeOnly holds the default value on creation for the "claude_code_only" field.
+	DefaultClaudeCodeOnly bool
 )
 
 // OrderOption defines the ordering options for the Group queries.
@@ -291,6 +299,16 @@ func ByImagePrice4k(opts ...sql.OrderTermOption) OrderOption {
 	return sql.OrderByField(FieldImagePrice4k, opts...).ToFunc()
 }
 
+// ByClaudeCodeOnly orders the results by the claude_code_only field.
+func ByClaudeCodeOnly(opts ...sql.OrderTermOption) OrderOption {
+	return sql.OrderByField(FieldClaudeCodeOnly, opts...).ToFunc()
+}
+
+// ByFallbackGroupID orders the results by the fallback_group_id field.
+func ByFallbackGroupID(opts ...sql.OrderTermOption) OrderOption {
+	return sql.OrderByField(FieldFallbackGroupID, opts...).ToFunc()
+}
+
 // ByAPIKeysCount orders the results by api_keys count.
 func ByAPIKeysCount(opts ...sql.OrderTermOption) OrderOption {
 	return func(s *sql.Selector) {

backend/ent/group/where.go

@@ -140,6 +140,16 @@ func ImagePrice4k(v float64) predicate.Group {
 	return predicate.Group(sql.FieldEQ(FieldImagePrice4k, v))
 }
 
+// ClaudeCodeOnly applies equality check predicate on the "claude_code_only" field. It's identical to ClaudeCodeOnlyEQ.
+func ClaudeCodeOnly(v bool) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldClaudeCodeOnly, v))
+}
+
+// FallbackGroupID applies equality check predicate on the "fallback_group_id" field. It's identical to FallbackGroupIDEQ.
+func FallbackGroupID(v int64) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldFallbackGroupID, v))
+}
+
 // CreatedAtEQ applies the EQ predicate on the "created_at" field.
 func CreatedAtEQ(v time.Time) predicate.Group {
 	return predicate.Group(sql.FieldEQ(FieldCreatedAt, v))
@@ -995,6 +1005,66 @@ func ImagePrice4kNotNil() predicate.Group {
 	return predicate.Group(sql.FieldNotNull(FieldImagePrice4k))
 }
 
+// ClaudeCodeOnlyEQ applies the EQ predicate on the "claude_code_only" field.
+func ClaudeCodeOnlyEQ(v bool) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldClaudeCodeOnly, v))
+}
+
+// ClaudeCodeOnlyNEQ applies the NEQ predicate on the "claude_code_only" field.
+func ClaudeCodeOnlyNEQ(v bool) predicate.Group {
+	return predicate.Group(sql.FieldNEQ(FieldClaudeCodeOnly, v))
+}
+
+// FallbackGroupIDEQ applies the EQ predicate on the "fallback_group_id" field.
+func FallbackGroupIDEQ(v int64) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldFallbackGroupID, v))
+}
+
+// FallbackGroupIDNEQ applies the NEQ predicate on the "fallback_group_id" field.
+func FallbackGroupIDNEQ(v int64) predicate.Group {
+	return predicate.Group(sql.FieldNEQ(FieldFallbackGroupID, v))
+}
+
+// FallbackGroupIDIn applies the In predicate on the "fallback_group_id" field.
+func FallbackGroupIDIn(vs ...int64) predicate.Group {
+	return predicate.Group(sql.FieldIn(FieldFallbackGroupID, vs...))
+}
+
+// FallbackGroupIDNotIn applies the NotIn predicate on the "fallback_group_id" field.
+func FallbackGroupIDNotIn(vs ...int64) predicate.Group {
+	return predicate.Group(sql.FieldNotIn(FieldFallbackGroupID, vs...))
+}
+
+// FallbackGroupIDGT applies the GT predicate on the "fallback_group_id" field.
+func FallbackGroupIDGT(v int64) predicate.Group {
+	return predicate.Group(sql.FieldGT(FieldFallbackGroupID, v))
+}
+
+// FallbackGroupIDGTE applies the GTE predicate on the "fallback_group_id" field.
+func FallbackGroupIDGTE(v int64) predicate.Group {
+	return predicate.Group(sql.FieldGTE(FieldFallbackGroupID, v))
+}
+
+// FallbackGroupIDLT applies the LT predicate on the "fallback_group_id" field.
+func FallbackGroupIDLT(v int64) predicate.Group {
+	return predicate.Group(sql.FieldLT(FieldFallbackGroupID, v))
+}
+
+// FallbackGroupIDLTE applies the LTE predicate on the "fallback_group_id" field.
+func FallbackGroupIDLTE(v int64) predicate.Group {
+	return predicate.Group(sql.FieldLTE(FieldFallbackGroupID, v))
+}
+
+// FallbackGroupIDIsNil applies the IsNil predicate on the "fallback_group_id" field.
+func FallbackGroupIDIsNil() predicate.Group {
+	return predicate.Group(sql.FieldIsNull(FieldFallbackGroupID))
+}
+
+// FallbackGroupIDNotNil applies the NotNil predicate on the "fallback_group_id" field.
+func FallbackGroupIDNotNil() predicate.Group {
+	return predicate.Group(sql.FieldNotNull(FieldFallbackGroupID))
+}
+
 // HasAPIKeys applies the HasEdge predicate on the "api_keys" edge.
 func HasAPIKeys() predicate.Group {
 	return predicate.Group(func(s *sql.Selector) {

backend/ent/group_create.go

@@ -258,6 +258,34 @@ func (_c *GroupCreate) SetNillableImagePrice4k(v *float64) *GroupCreate {
 	return _c
 }
 
+// SetClaudeCodeOnly sets the "claude_code_only" field.
+func (_c *GroupCreate) SetClaudeCodeOnly(v bool) *GroupCreate {
+	_c.mutation.SetClaudeCodeOnly(v)
+	return _c
+}
+
+// SetNillableClaudeCodeOnly sets the "claude_code_only" field if the given value is not nil.
+func (_c *GroupCreate) SetNillableClaudeCodeOnly(v *bool) *GroupCreate {
+	if v != nil {
+		_c.SetClaudeCodeOnly(*v)
+	}
+	return _c
+}
+
+// SetFallbackGroupID sets the "fallback_group_id" field.
+func (_c *GroupCreate) SetFallbackGroupID(v int64) *GroupCreate {
+	_c.mutation.SetFallbackGroupID(v)
+	return _c
+}
+
+// SetNillableFallbackGroupID sets the "fallback_group_id" field if the given value is not nil.
+func (_c *GroupCreate) SetNillableFallbackGroupID(v *int64) *GroupCreate {
+	if v != nil {
+		_c.SetFallbackGroupID(*v)
+	}
+	return _c
+}
+
 // AddAPIKeyIDs adds the "api_keys" edge to the APIKey entity by IDs.
 func (_c *GroupCreate) AddAPIKeyIDs(ids ...int64) *GroupCreate {
 	_c.mutation.AddAPIKeyIDs(ids...)
@@ -423,6 +451,10 @@ func (_c *GroupCreate) defaults() error {
 		v := group.DefaultDefaultValidityDays
 		_c.mutation.SetDefaultValidityDays(v)
 	}
+	if _, ok := _c.mutation.ClaudeCodeOnly(); !ok {
+		v := group.DefaultClaudeCodeOnly
+		_c.mutation.SetClaudeCodeOnly(v)
+	}
 	return nil
 }
 
@@ -475,6 +507,9 @@ func (_c *GroupCreate) check() error {
 	if _, ok := _c.mutation.DefaultValidityDays(); !ok {
 		return &ValidationError{Name: "default_validity_days", err: errors.New(`ent: missing required field "Group.default_validity_days"`)}
 	}
+	if _, ok := _c.mutation.ClaudeCodeOnly(); !ok {
+		return &ValidationError{Name: "claude_code_only", err: errors.New(`ent: missing required field "Group.claude_code_only"`)}
+	}
 	return nil
 }
 
@@ -570,6 +605,14 @@ func (_c *GroupCreate) createSpec() (*Group, *sqlgraph.CreateSpec) {
 		_spec.SetField(group.FieldImagePrice4k, field.TypeFloat64, value)
 		_node.ImagePrice4k = &value
 	}
+	if value, ok := _c.mutation.ClaudeCodeOnly(); ok {
+		_spec.SetField(group.FieldClaudeCodeOnly, field.TypeBool, value)
+		_node.ClaudeCodeOnly = value
+	}
+	if value, ok := _c.mutation.FallbackGroupID(); ok {
+		_spec.SetField(group.FieldFallbackGroupID, field.TypeInt64, value)
+		_node.FallbackGroupID = &value
+	}
 	if nodes := _c.mutation.APIKeysIDs(); len(nodes) > 0 {
 		edge := &sqlgraph.EdgeSpec{
 			Rel:     sqlgraph.O2M,
@@ -1014,6 +1057,42 @@ func (u *GroupUpsert) ClearImagePrice4k() *GroupUpsert {
 	return u
 }
 
+// SetClaudeCodeOnly sets the "claude_code_only" field.
+func (u *GroupUpsert) SetClaudeCodeOnly(v bool) *GroupUpsert {
+	u.Set(group.FieldClaudeCodeOnly, v)
+	return u
+}
+
+// UpdateClaudeCodeOnly sets the "claude_code_only" field to the value that was provided on create.
+func (u *GroupUpsert) UpdateClaudeCodeOnly() *GroupUpsert {
+	u.SetExcluded(group.FieldClaudeCodeOnly)
+	return u
+}
+
+// SetFallbackGroupID sets the "fallback_group_id" field.
+func (u *GroupUpsert) SetFallbackGroupID(v int64) *GroupUpsert {
+	u.Set(group.FieldFallbackGroupID, v)
+	return u
+}
+
+// UpdateFallbackGroupID sets the "fallback_group_id" field to the value that was provided on create.
+func (u *GroupUpsert) UpdateFallbackGroupID() *GroupUpsert {
+	u.SetExcluded(group.FieldFallbackGroupID)
+	return u
+}
+
+// AddFallbackGroupID adds v to the "fallback_group_id" field.
+func (u *GroupUpsert) AddFallbackGroupID(v int64) *GroupUpsert {
+	u.Add(group.FieldFallbackGroupID, v)
+	return u
+}
+
+// ClearFallbackGroupID clears the value of the "fallback_group_id" field.
+func (u *GroupUpsert) ClearFallbackGroupID() *GroupUpsert {
+	u.SetNull(group.FieldFallbackGroupID)
+	return u
+}
+
 // UpdateNewValues updates the mutable fields using the new values that were set on create.
 // Using this option is equivalent to using:
 //
@@ -1395,6 +1474,48 @@ func (u *GroupUpsertOne) ClearImagePrice4k() *GroupUpsertOne {
 	})
 }
 
+// SetClaudeCodeOnly sets the "claude_code_only" field.
+func (u *GroupUpsertOne) SetClaudeCodeOnly(v bool) *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.SetClaudeCodeOnly(v)
+	})
+}
+
+// UpdateClaudeCodeOnly sets the "claude_code_only" field to the value that was provided on create.
+func (u *GroupUpsertOne) UpdateClaudeCodeOnly() *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.UpdateClaudeCodeOnly()
+	})
+}
+
+// SetFallbackGroupID sets the "fallback_group_id" field.
+func (u *GroupUpsertOne) SetFallbackGroupID(v int64) *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.SetFallbackGroupID(v)
+	})
+}
+
+// AddFallbackGroupID adds v to the "fallback_group_id" field.
+func (u *GroupUpsertOne) AddFallbackGroupID(v int64) *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.AddFallbackGroupID(v)
+	})
+}
+
+// UpdateFallbackGroupID sets the "fallback_group_id" field to the value that was provided on create.
+func (u *GroupUpsertOne) UpdateFallbackGroupID() *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.UpdateFallbackGroupID()
+	})
+}
+
+// ClearFallbackGroupID clears the value of the "fallback_group_id" field.
+func (u *GroupUpsertOne) ClearFallbackGroupID() *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.ClearFallbackGroupID()
+	})
+}
+
 // Exec executes the query.
 func (u *GroupUpsertOne) Exec(ctx context.Context) error {
 	if len(u.create.conflict) == 0 {
@@ -1942,6 +2063,48 @@ func (u *GroupUpsertBulk) ClearImagePrice4k() *GroupUpsertBulk {
 	})
 }
 
+// SetClaudeCodeOnly sets the "claude_code_only" field.
+func (u *GroupUpsertBulk) SetClaudeCodeOnly(v bool) *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.SetClaudeCodeOnly(v)
+	})
+}
+
+// UpdateClaudeCodeOnly sets the "claude_code_only" field to the value that was provided on create.
+func (u *GroupUpsertBulk) UpdateClaudeCodeOnly() *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.UpdateClaudeCodeOnly()
+	})
+}
+
+// SetFallbackGroupID sets the "fallback_group_id" field.
+func (u *GroupUpsertBulk) SetFallbackGroupID(v int64) *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.SetFallbackGroupID(v)
+	})
+}
+
+// AddFallbackGroupID adds v to the "fallback_group_id" field.
+func (u *GroupUpsertBulk) AddFallbackGroupID(v int64) *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.AddFallbackGroupID(v)
+	})
+}
+
+// UpdateFallbackGroupID sets the "fallback_group_id" field to the value that was provided on create.
+func (u *GroupUpsertBulk) UpdateFallbackGroupID() *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.UpdateFallbackGroupID()
+	})
+}
+
+// ClearFallbackGroupID clears the value of the "fallback_group_id" field.
+func (u *GroupUpsertBulk) ClearFallbackGroupID() *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.ClearFallbackGroupID()
+	})
+}
+
 // Exec executes the query.
 func (u *GroupUpsertBulk) Exec(ctx context.Context) error {
 	if u.create.err != nil {

backend/ent/group_update.go

@@ -354,6 +354,47 @@ func (_u *GroupUpdate) ClearImagePrice4k() *GroupUpdate {
 	return _u
 }
 
+// SetClaudeCodeOnly sets the "claude_code_only" field.
+func (_u *GroupUpdate) SetClaudeCodeOnly(v bool) *GroupUpdate {
+	_u.mutation.SetClaudeCodeOnly(v)
+	return _u
+}
+
+// SetNillableClaudeCodeOnly sets the "claude_code_only" field if the given value is not nil.
+func (_u *GroupUpdate) SetNillableClaudeCodeOnly(v *bool) *GroupUpdate {
+	if v != nil {
+		_u.SetClaudeCodeOnly(*v)
+	}
+	return _u
+}
+
+// SetFallbackGroupID sets the "fallback_group_id" field.
+func (_u *GroupUpdate) SetFallbackGroupID(v int64) *GroupUpdate {
+	_u.mutation.ResetFallbackGroupID()
+	_u.mutation.SetFallbackGroupID(v)
+	return _u
+}
+
+// SetNillableFallbackGroupID sets the "fallback_group_id" field if the given value is not nil.
+func (_u *GroupUpdate) SetNillableFallbackGroupID(v *int64) *GroupUpdate {
+	if v != nil {
+		_u.SetFallbackGroupID(*v)
+	}
+	return _u
+}
+
+// AddFallbackGroupID adds value to the "fallback_group_id" field.
+func (_u *GroupUpdate) AddFallbackGroupID(v int64) *GroupUpdate {
+	_u.mutation.AddFallbackGroupID(v)
+	return _u
+}
+
+// ClearFallbackGroupID clears the value of the "fallback_group_id" field.
+func (_u *GroupUpdate) ClearFallbackGroupID() *GroupUpdate {
+	_u.mutation.ClearFallbackGroupID()
+	return _u
+}
+
 // AddAPIKeyIDs adds the "api_keys" edge to the APIKey entity by IDs.
 func (_u *GroupUpdate) AddAPIKeyIDs(ids ...int64) *GroupUpdate {
 	_u.mutation.AddAPIKeyIDs(ids...)
@@ -750,6 +791,18 @@ func (_u *GroupUpdate) sqlSave(ctx context.Context) (_node int, err error) {
 	if _u.mutation.ImagePrice4kCleared() {
 		_spec.ClearField(group.FieldImagePrice4k, field.TypeFloat64)
 	}
+	if value, ok := _u.mutation.ClaudeCodeOnly(); ok {
+		_spec.SetField(group.FieldClaudeCodeOnly, field.TypeBool, value)
+	}
+	if value, ok := _u.mutation.FallbackGroupID(); ok {
+		_spec.SetField(group.FieldFallbackGroupID, field.TypeInt64, value)
+	}
+	if value, ok := _u.mutation.AddedFallbackGroupID(); ok {
+		_spec.AddField(group.FieldFallbackGroupID, field.TypeInt64, value)
+	}
+	if _u.mutation.FallbackGroupIDCleared() {
+		_spec.ClearField(group.FieldFallbackGroupID, field.TypeInt64)
+	}
 	if _u.mutation.APIKeysCleared() {
 		edge := &sqlgraph.EdgeSpec{
 			Rel:     sqlgraph.O2M,
@@ -1384,6 +1437,47 @@ func (_u *GroupUpdateOne) ClearImagePrice4k() *GroupUpdateOne {
 	return _u
 }
 
+// SetClaudeCodeOnly sets the "claude_code_only" field.
+func (_u *GroupUpdateOne) SetClaudeCodeOnly(v bool) *GroupUpdateOne {
+	_u.mutation.SetClaudeCodeOnly(v)
+	return _u
+}
+
+// SetNillableClaudeCodeOnly sets the "claude_code_only" field if the given value is not nil.
+func (_u *GroupUpdateOne) SetNillableClaudeCodeOnly(v *bool) *GroupUpdateOne {
+	if v != nil {
+		_u.SetClaudeCodeOnly(*v)
+	}
+	return _u
+}
+
+// SetFallbackGroupID sets the "fallback_group_id" field.
+func (_u *GroupUpdateOne) SetFallbackGroupID(v int64) *GroupUpdateOne {
+	_u.mutation.ResetFallbackGroupID()
+	_u.mutation.SetFallbackGroupID(v)
+	return _u
+}
+
+// SetNillableFallbackGroupID sets the "fallback_group_id" field if the given value is not nil.
+func (_u *GroupUpdateOne) SetNillableFallbackGroupID(v *int64) *GroupUpdateOne {
+	if v != nil {
+		_u.SetFallbackGroupID(*v)
+	}
+	return _u
+}
+
+// AddFallbackGroupID adds value to the "fallback_group_id" field.
+func (_u *GroupUpdateOne) AddFallbackGroupID(v int64) *GroupUpdateOne {
+	_u.mutation.AddFallbackGroupID(v)
+	return _u
+}
+
+// ClearFallbackGroupID clears the value of the "fallback_group_id" field.
+func (_u *GroupUpdateOne) ClearFallbackGroupID() *GroupUpdateOne {
+	_u.mutation.ClearFallbackGroupID()
+	return _u
+}
+
 // AddAPIKeyIDs adds the "api_keys" edge to the APIKey entity by IDs.
 func (_u *GroupUpdateOne) AddAPIKeyIDs(ids ...int64) *GroupUpdateOne {
 	_u.mutation.AddAPIKeyIDs(ids...)
@@ -1810,6 +1904,18 @@ func (_u *GroupUpdateOne) sqlSave(ctx context.Context) (_node *Group, err error)
 	if _u.mutation.ImagePrice4kCleared() {
 		_spec.ClearField(group.FieldImagePrice4k, field.TypeFloat64)
 	}
+	if value, ok := _u.mutation.ClaudeCodeOnly(); ok {
+		_spec.SetField(group.FieldClaudeCodeOnly, field.TypeBool, value)
+	}
+	if value, ok := _u.mutation.FallbackGroupID(); ok {
+		_spec.SetField(group.FieldFallbackGroupID, field.TypeInt64, value)
+	}
+	if value, ok := _u.mutation.AddedFallbackGroupID(); ok {
+		_spec.AddField(group.FieldFallbackGroupID, field.TypeInt64, value)
+	}
+	if _u.mutation.FallbackGroupIDCleared() {
+		_spec.ClearField(group.FieldFallbackGroupID, field.TypeInt64)
+	}
 	if _u.mutation.APIKeysCleared() {
 		edge := &sqlgraph.EdgeSpec{
 			Rel:     sqlgraph.O2M,

backend/ent/migrate/schema.go

@@ -221,6 +221,8 @@ var (
 		{Name: "image_price_1k", Type: field.TypeFloat64, Nullable: true, SchemaType: map[string]string{"postgres": "decimal(20,8)"}},
 		{Name: "image_price_2k", Type: field.TypeFloat64, Nullable: true, SchemaType: map[string]string{"postgres": "decimal(20,8)"}},
 		{Name: "image_price_4k", Type: field.TypeFloat64, Nullable: true, SchemaType: map[string]string{"postgres": "decimal(20,8)"}},
+		{Name: "claude_code_only", Type: field.TypeBool, Default: false},
+		{Name: "fallback_group_id", Type: field.TypeInt64, Nullable: true},
 	}
 	// GroupsTable holds the schema information for the "groups" table.
 	GroupsTable = &schema.Table{

backend/ent/mutation.go

@@ -3590,6 +3590,9 @@ type GroupMutation struct {
 	addimage_price_2k        *float64
 	image_price_4k           *float64
 	addimage_price_4k        *float64
+	claude_code_only         *bool
+	fallback_group_id        *int64
+	addfallback_group_id     *int64
 	clearedFields            map[string]struct{}
 	api_keys                 map[int64]struct{}
 	removedapi_keys          map[int64]struct{}
@@ -4594,6 +4597,112 @@ func (m *GroupMutation) ResetImagePrice4k() {
 	delete(m.clearedFields, group.FieldImagePrice4k)
 }
 
+// SetClaudeCodeOnly sets the "claude_code_only" field.
+func (m *GroupMutation) SetClaudeCodeOnly(b bool) {
+	m.claude_code_only = &b
+}
+
+// ClaudeCodeOnly returns the value of the "claude_code_only" field in the mutation.
+func (m *GroupMutation) ClaudeCodeOnly() (r bool, exists bool) {
+	v := m.claude_code_only
+	if v == nil {
+		return
+	}
+	return *v, true
+}
+
+// OldClaudeCodeOnly returns the old "claude_code_only" field's value of the Group entity.
+// If the Group object wasn't provided to the builder, the object is fetched from the database.
+// An error is returned if the mutation operation is not UpdateOne, or the database query fails.
+func (m *GroupMutation) OldClaudeCodeOnly(ctx context.Context) (v bool, err error) {
+	if !m.op.Is(OpUpdateOne) {
+		return v, errors.New("OldClaudeCodeOnly is only allowed on UpdateOne operations")
+	}
+	if m.id == nil || m.oldValue == nil {
+		return v, errors.New("OldClaudeCodeOnly requires an ID field in the mutation")
+	}
+	oldValue, err := m.oldValue(ctx)
+	if err != nil {
+		return v, fmt.Errorf("querying old value for OldClaudeCodeOnly: %w", err)
+	}
+	return oldValue.ClaudeCodeOnly, nil
+}
+
+// ResetClaudeCodeOnly resets all changes to the "claude_code_only" field.
+func (m *GroupMutation) ResetClaudeCodeOnly() {
+	m.claude_code_only = nil
+}
+
+// SetFallbackGroupID sets the "fallback_group_id" field.
+func (m *GroupMutation) SetFallbackGroupID(i int64) {
+	m.fallback_group_id = &i
+	m.addfallback_group_id = nil
+}
+
+// FallbackGroupID returns the value of the "fallback_group_id" field in the mutation.
+func (m *GroupMutation) FallbackGroupID() (r int64, exists bool) {
+	v := m.fallback_group_id
+	if v == nil {
+		return
+	}
+	return *v, true
+}
+
+// OldFallbackGroupID returns the old "fallback_group_id" field's value of the Group entity.
+// If the Group object wasn't provided to the builder, the object is fetched from the database.
+// An error is returned if the mutation operation is not UpdateOne, or the database query fails.
+func (m *GroupMutation) OldFallbackGroupID(ctx context.Context) (v *int64, err error) {
+	if !m.op.Is(OpUpdateOne) {
+		return v, errors.New("OldFallbackGroupID is only allowed on UpdateOne operations")
+	}
+	if m.id == nil || m.oldValue == nil {
+		return v, errors.New("OldFallbackGroupID requires an ID field in the mutation")
+	}
+	oldValue, err := m.oldValue(ctx)
+	if err != nil {
+		return v, fmt.Errorf("querying old value for OldFallbackGroupID: %w", err)
+	}
+	return oldValue.FallbackGroupID, nil
+}
+
+// AddFallbackGroupID adds i to the "fallback_group_id" field.
+func (m *GroupMutation) AddFallbackGroupID(i int64) {
+	if m.addfallback_group_id != nil {
+		*m.addfallback_group_id += i
+	} else {
+		m.addfallback_group_id = &i
+	}
+}
+
+// AddedFallbackGroupID returns the value that was added to the "fallback_group_id" field in this mutation.
+func (m *GroupMutation) AddedFallbackGroupID() (r int64, exists bool) {
+	v := m.addfallback_group_id
+	if v == nil {
+		return
+	}
+	return *v, true
+}
+
+// ClearFallbackGroupID clears the value of the "fallback_group_id" field.
+func (m *GroupMutation) ClearFallbackGroupID() {
+	m.fallback_group_id = nil
+	m.addfallback_group_id = nil
+	m.clearedFields[group.FieldFallbackGroupID] = struct{}{}
+}
+
+// FallbackGroupIDCleared returns if the "fallback_group_id" field was cleared in this mutation.
+func (m *GroupMutation) FallbackGroupIDCleared() bool {
+	_, ok := m.clearedFields[group.FieldFallbackGroupID]
+	return ok
+}
+
+// ResetFallbackGroupID resets all changes to the "fallback_group_id" field.
+func (m *GroupMutation) ResetFallbackGroupID() {
+	m.fallback_group_id = nil
+	m.addfallback_group_id = nil
+	delete(m.clearedFields, group.FieldFallbackGroupID)
+}
+
 // AddAPIKeyIDs adds the "api_keys" edge to the APIKey entity by ids.
 func (m *GroupMutation) AddAPIKeyIDs(ids ...int64) {
 	if m.api_keys == nil {
@@ -4952,7 +5061,7 @@ func (m *GroupMutation) Type() string {
 // order to get all numeric fields that were incremented/decremented, call
 // AddedFields().
 func (m *GroupMutation) Fields() []string {
-	fields := make([]string, 0, 17)
+	fields := make([]string, 0, 19)
 	if m.created_at != nil {
 		fields = append(fields, group.FieldCreatedAt)
 	}
@@ -5004,6 +5113,12 @@ func (m *GroupMutation) Fields() []string {
 	if m.image_price_4k != nil {
 		fields = append(fields, group.FieldImagePrice4k)
 	}
+	if m.claude_code_only != nil {
+		fields = append(fields, group.FieldClaudeCodeOnly)
+	}
+	if m.fallback_group_id != nil {
+		fields = append(fields, group.FieldFallbackGroupID)
+	}
 	return fields
 }
 
@@ -5046,6 +5161,10 @@ func (m *GroupMutation) Field(name string) (ent.Value, bool) {
 		return m.ImagePrice2k()
 	case group.FieldImagePrice4k:
 		return m.ImagePrice4k()
+	case group.FieldClaudeCodeOnly:
+		return m.ClaudeCodeOnly()
+	case group.FieldFallbackGroupID:
+		return m.FallbackGroupID()
 	}
 	return nil, false
 }
@@ -5089,6 +5208,10 @@ func (m *GroupMutation) OldField(ctx context.Context, name string) (ent.Value, e
 		return m.OldImagePrice2k(ctx)
 	case group.FieldImagePrice4k:
 		return m.OldImagePrice4k(ctx)
+	case group.FieldClaudeCodeOnly:
+		return m.OldClaudeCodeOnly(ctx)
+	case group.FieldFallbackGroupID:
+		return m.OldFallbackGroupID(ctx)
 	}
 	return nil, fmt.Errorf("unknown Group field %s", name)
 }
@@ -5217,6 +5340,20 @@ func (m *GroupMutation) SetField(name string, value ent.Value) error {
 		}
 		m.SetImagePrice4k(v)
 		return nil
+	case group.FieldClaudeCodeOnly:
+		v, ok := value.(bool)
+		if !ok {
+			return fmt.Errorf("unexpected type %T for field %s", value, name)
+		}
+		m.SetClaudeCodeOnly(v)
+		return nil
+	case group.FieldFallbackGroupID:
+		v, ok := value.(int64)
+		if !ok {
+			return fmt.Errorf("unexpected type %T for field %s", value, name)
+		}
+		m.SetFallbackGroupID(v)
+		return nil
 	}
 	return fmt.Errorf("unknown Group field %s", name)
 }
@@ -5249,6 +5386,9 @@ func (m *GroupMutation) AddedFields() []string {
 	if m.addimage_price_4k != nil {
 		fields = append(fields, group.FieldImagePrice4k)
 	}
+	if m.addfallback_group_id != nil {
+		fields = append(fields, group.FieldFallbackGroupID)
+	}
 	return fields
 }
 
@@ -5273,6 +5413,8 @@ func (m *GroupMutation) AddedField(name string) (ent.Value, bool) {
 		return m.AddedImagePrice2k()
 	case group.FieldImagePrice4k:
 		return m.AddedImagePrice4k()
+	case group.FieldFallbackGroupID:
+		return m.AddedFallbackGroupID()
 	}
 	return nil, false
 }
@@ -5338,6 +5480,13 @@ func (m *GroupMutation) AddField(name string, value ent.Value) error {
 		}
 		m.AddImagePrice4k(v)
 		return nil
+	case group.FieldFallbackGroupID:
+		v, ok := value.(int64)
+		if !ok {
+			return fmt.Errorf("unexpected type %T for field %s", value, name)
+		}
+		m.AddFallbackGroupID(v)
+		return nil
 	}
 	return fmt.Errorf("unknown Group numeric field %s", name)
 }
@@ -5370,6 +5519,9 @@ func (m *GroupMutation) ClearedFields() []string {
 	if m.FieldCleared(group.FieldImagePrice4k) {
 		fields = append(fields, group.FieldImagePrice4k)
 	}
+	if m.FieldCleared(group.FieldFallbackGroupID) {
+		fields = append(fields, group.FieldFallbackGroupID)
+	}
 	return fields
 }
 
@@ -5408,6 +5560,9 @@ func (m *GroupMutation) ClearField(name string) error {
 	case group.FieldImagePrice4k:
 		m.ClearImagePrice4k()
 		return nil
+	case group.FieldFallbackGroupID:
+		m.ClearFallbackGroupID()
+		return nil
 	}
 	return fmt.Errorf("unknown Group nullable field %s", name)
 }
@@ -5467,6 +5622,12 @@ func (m *GroupMutation) ResetField(name string) error {
 	case group.FieldImagePrice4k:
 		m.ResetImagePrice4k()
 		return nil
+	case group.FieldClaudeCodeOnly:
+		m.ResetClaudeCodeOnly()
+		return nil
+	case group.FieldFallbackGroupID:
+		m.ResetFallbackGroupID()
+		return nil
 	}
 	return fmt.Errorf("unknown Group field %s", name)
 }

backend/ent/runtime/runtime.go

@@ -270,6 +270,10 @@ func init() {
 	groupDescDefaultValidityDays := groupFields[10].Descriptor()
 	// group.DefaultDefaultValidityDays holds the default value on creation for the default_validity_days field.
 	group.DefaultDefaultValidityDays = groupDescDefaultValidityDays.Default.(int)
+	// groupDescClaudeCodeOnly is the schema descriptor for claude_code_only field.
+	groupDescClaudeCodeOnly := groupFields[14].Descriptor()
+	// group.DefaultClaudeCodeOnly holds the default value on creation for the claude_code_only field.
+	group.DefaultClaudeCodeOnly = groupDescClaudeCodeOnly.Default.(bool)
 	proxyMixin := schema.Proxy{}.Mixin()
 	proxyMixinHooks1 := proxyMixin[1].Hooks()
 	proxy.Hooks[0] = proxyMixinHooks1[0]

backend/ent/schema/group.go

@@ -86,6 +86,15 @@ func (Group) Fields() []ent.Field {
 			Optional().
 			Nillable().
 			SchemaType(map[string]string{dialect.Postgres: "decimal(20,8)"}),
+
+		// Claude Code 客户端限制 (added by migration 029)
+		field.Bool("claude_code_only").
+			Default(false).
+			Comment("是否仅允许 Claude Code 客户端"),
+		field.Int64("fallback_group_id").
+			Optional().
+			Nillable().
+			Comment("非 Claude Code 请求降级使用的分组 ID"),
 	}
 }
 
@@ -101,6 +110,8 @@ func (Group) Edges() []ent.Edge {
 		edge.From("allowed_users", User.Type).
 			Ref("allowed_groups").
 			Through("user_allowed_groups", UserAllowedGroup.Type),
+		// 注意：fallback_group_id 直接作为字段使用，不定义 edge
+		// 这样允许多个分组指向同一个降级分组（M2O 关系）
 	}
 }
 

backend/internal/handler/admin/group_handler.go

@@ -34,9 +34,11 @@ type CreateGroupRequest struct {
 	WeeklyLimitUSD   *float64 `json:"weekly_limit_usd"`
 	MonthlyLimitUSD  *float64 `json:"monthly_limit_usd"`
 	// 图片生成计费配置（antigravity 和 gemini 平台使用，负数表示清除配置）
-	ImagePrice1K *float64 `json:"image_price_1k"`
-	ImagePrice2K *float64 `json:"image_price_2k"`
-	ImagePrice4K *float64 `json:"image_price_4k"`
+	ImagePrice1K    *float64 `json:"image_price_1k"`
+	ImagePrice2K    *float64 `json:"image_price_2k"`
+	ImagePrice4K    *float64 `json:"image_price_4k"`
+	ClaudeCodeOnly  bool     `json:"claude_code_only"`
+	FallbackGroupID *int64   `json:"fallback_group_id"`
 }
 
 // UpdateGroupRequest represents update group request
@@ -52,9 +54,11 @@ type UpdateGroupRequest struct {
 	WeeklyLimitUSD   *float64 `json:"weekly_limit_usd"`
 	MonthlyLimitUSD  *float64 `json:"monthly_limit_usd"`
 	// 图片生成计费配置（antigravity 和 gemini 平台使用，负数表示清除配置）
-	ImagePrice1K *float64 `json:"image_price_1k"`
-	ImagePrice2K *float64 `json:"image_price_2k"`
-	ImagePrice4K *float64 `json:"image_price_4k"`
+	ImagePrice1K    *float64 `json:"image_price_1k"`
+	ImagePrice2K    *float64 `json:"image_price_2k"`
+	ImagePrice4K    *float64 `json:"image_price_4k"`
+	ClaudeCodeOnly  *bool    `json:"claude_code_only"`
+	FallbackGroupID *int64   `json:"fallback_group_id"`
 }
 
 // List handles listing all groups with pagination
@@ -150,6 +154,8 @@ func (h *GroupHandler) Create(c *gin.Context) {
 		ImagePrice1K:     req.ImagePrice1K,
 		ImagePrice2K:     req.ImagePrice2K,
 		ImagePrice4K:     req.ImagePrice4K,
+		ClaudeCodeOnly:   req.ClaudeCodeOnly,
+		FallbackGroupID:  req.FallbackGroupID,
 	})
 	if err != nil {
 		response.ErrorFrom(c, err)
@@ -188,6 +194,8 @@ func (h *GroupHandler) Update(c *gin.Context) {
 		ImagePrice1K:     req.ImagePrice1K,
 		ImagePrice2K:     req.ImagePrice2K,
 		ImagePrice4K:     req.ImagePrice4K,
+		ClaudeCodeOnly:   req.ClaudeCodeOnly,
+		FallbackGroupID:  req.FallbackGroupID,
 	})
 	if err != nil {
 		response.ErrorFrom(c, err)

backend/internal/handler/admin/proxy_handler.go

@@ -52,15 +52,15 @@ func (h *ProxyHandler) List(c *gin.Context) {
 	status := c.Query("status")
 	search := c.Query("search")
 
-	proxies, total, err := h.adminService.ListProxies(c.Request.Context(), page, pageSize, protocol, status, search)
+	proxies, total, err := h.adminService.ListProxiesWithAccountCount(c.Request.Context(), page, pageSize, protocol, status, search)
 	if err != nil {
 		response.ErrorFrom(c, err)
 		return
 	}
 
-	out := make([]dto.Proxy, 0, len(proxies))
+	out := make([]dto.ProxyWithAccountCount, 0, len(proxies))
 	for i := range proxies {
-		out = append(out, *dto.ProxyFromService(&proxies[i]))
+		out = append(out, *dto.ProxyWithAccountCountFromService(&proxies[i]))
 	}
 	response.Paginated(c, out, total, page, pageSize)
 }

backend/internal/handler/admin/usage_handler.go

@@ -144,7 +144,7 @@ func (h *UsageHandler) List(c *gin.Context) {
 
 	out := make([]dto.UsageLog, 0, len(records))
 	for i := range records {
-		out = append(out, *dto.UsageLogFromService(&records[i]))
+		out = append(out, *dto.UsageLogFromServiceAdmin(&records[i]))
 	}
 	response.Paginated(c, out, result.Total, page, pageSize)
 }

backend/internal/handler/dto/mappers.go

@@ -85,6 +85,8 @@ func GroupFromServiceShallow(g *service.Group) *Group {
 		ImagePrice1K:     g.ImagePrice1K,
 		ImagePrice2K:     g.ImagePrice2K,
 		ImagePrice4K:     g.ImagePrice4K,
+		ClaudeCodeOnly:   g.ClaudeCodeOnly,
+		FallbackGroupID:  g.FallbackGroupID,
 		CreatedAt:        g.CreatedAt,
 		UpdatedAt:        g.UpdatedAt,
 		AccountCount:     g.AccountCount,
@@ -234,7 +236,21 @@ func RedeemCodeFromService(rc *service.RedeemCode) *RedeemCode {
 	}
 }
 
-func UsageLogFromService(l *service.UsageLog) *UsageLog {
+// AccountSummaryFromService returns a minimal AccountSummary for usage log display.
+// Only includes ID and Name - no sensitive fields like Credentials, Proxy, etc.
+func AccountSummaryFromService(a *service.Account) *AccountSummary {
+	if a == nil {
+		return nil
+	}
+	return &AccountSummary{
+		ID:   a.ID,
+		Name: a.Name,
+	}
+}
+
+// usageLogFromServiceBase is a helper that converts service UsageLog to DTO.
+// The account parameter allows caller to control what Account info is included.
+func usageLogFromServiceBase(l *service.UsageLog, account *AccountSummary) *UsageLog {
 	if l == nil {
 		return nil
 	}
@@ -266,15 +282,31 @@ func UsageLogFromService(l *service.UsageLog) *UsageLog {
 		FirstTokenMs:          l.FirstTokenMs,
 		ImageCount:            l.ImageCount,
 		ImageSize:             l.ImageSize,
+		UserAgent:             l.UserAgent,
 		CreatedAt:             l.CreatedAt,
 		User:                  UserFromServiceShallow(l.User),
 		APIKey:                APIKeyFromService(l.APIKey),
-		Account:               AccountFromService(l.Account),
+		Account:               account,
 		Group:                 GroupFromServiceShallow(l.Group),
 		Subscription:          UserSubscriptionFromService(l.Subscription),
 	}
 }
 
+// UsageLogFromService converts a service UsageLog to DTO for regular users.
+// It excludes Account details - users should not see account information.
+func UsageLogFromService(l *service.UsageLog) *UsageLog {
+	return usageLogFromServiceBase(l, nil)
+}
+
+// UsageLogFromServiceAdmin converts a service UsageLog to DTO for admin users.
+// It includes minimal Account info (ID, Name only).
+func UsageLogFromServiceAdmin(l *service.UsageLog) *UsageLog {
+	if l == nil {
+		return nil
+	}
+	return usageLogFromServiceBase(l, AccountSummaryFromService(l.Account))
+}
+
 func SettingFromService(s *service.Setting) *Setting {
 	if s == nil {
 		return nil

backend/internal/handler/dto/types.go

@@ -52,6 +52,10 @@ type Group struct {
 	ImagePrice2K *float64 `json:"image_price_2k"`
 	ImagePrice4K *float64 `json:"image_price_4k"`
 
+	// Claude Code 客户端限制
+	ClaudeCodeOnly  bool   `json:"claude_code_only"`
+	FallbackGroupID *int64 `json:"fallback_group_id"`
+
 	CreatedAt time.Time `json:"created_at"`
 	UpdatedAt time.Time `json:"updated_at"`
 
@@ -180,15 +184,25 @@ type UsageLog struct {
 	ImageCount int     `json:"image_count"`
 	ImageSize  *string `json:"image_size"`
 
+	// User-Agent
+	UserAgent *string `json:"user_agent"`
+
 	CreatedAt time.Time `json:"created_at"`
 
 	User         *User             `json:"user,omitempty"`
 	APIKey       *APIKey           `json:"api_key,omitempty"`
-	Account      *Account          `json:"account,omitempty"`
+	Account      *AccountSummary   `json:"account,omitempty"` // Use minimal AccountSummary to prevent data leakage
 	Group        *Group            `json:"group,omitempty"`
 	Subscription *UserSubscription `json:"subscription,omitempty"`
 }
 
+// AccountSummary is a minimal account info for usage log display.
+// It intentionally excludes sensitive fields like Credentials, Proxy, etc.
+type AccountSummary struct {
+	ID   int64  `json:"id"`
+	Name string `json:"name"`
+}
+
 type Setting struct {
 	ID        int64     `json:"id"`
 	Key       string    `json:"key"`

backend/internal/handler/gateway_handler.go

@@ -96,6 +96,9 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 	reqModel := parsedReq.Model
 	reqStream := parsedReq.Stream
 
+	// 设置 Claude Code 客户端标识到 context（用于分组限制检查）
+	SetClaudeCodeClientContext(c, body)
+
 	// 验证 model 必填
 	if reqModel == "" {
 		h.errorResponse(c, http.StatusBadRequest, "invalid_request_error", "model is required")
@@ -229,7 +232,7 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 					h.handleConcurrencyError(c, err, "account", streamStarted)
 					return
 				}
-				if err := h.gatewayService.BindStickySession(c.Request.Context(), sessionKey, account.ID); err != nil {
+				if err := h.gatewayService.BindStickySession(c.Request.Context(), apiKey.GroupID, sessionKey, account.ID); err != nil {
 					log.Printf("Bind sticky session failed: %v", err)
 				}
 			}
@@ -357,7 +360,7 @@ func (h *GatewayHandler) Messages(c *gin.Context) {
 				h.handleConcurrencyError(c, err, "account", streamStarted)
 				return
 			}
-			if err := h.gatewayService.BindStickySession(c.Request.Context(), sessionKey, account.ID); err != nil {
+			if err := h.gatewayService.BindStickySession(c.Request.Context(), apiKey.GroupID, sessionKey, account.ID); err != nil {
 				log.Printf("Bind sticky session failed: %v", err)
 			}
 		}
@@ -683,6 +686,9 @@ func (h *GatewayHandler) CountTokens(c *gin.Context) {
 		return
 	}
 
+	// 设置 Claude Code 客户端标识到 context（用于分组限制检查）
+	SetClaudeCodeClientContext(c, body)
+
 	// 验证 model 必填
 	if parsedReq.Model == "" {
 		h.errorResponse(c, http.StatusBadRequest, "invalid_request_error", "model is required")

backend/internal/handler/gateway_helper.go

@@ -2,6 +2,7 @@ package handler
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"math/rand"
 	"net/http"
@@ -13,6 +14,26 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
+// claudeCodeValidator is a singleton validator for Claude Code client detection
+var claudeCodeValidator = service.NewClaudeCodeValidator()
+
+// SetClaudeCodeClientContext 检查请求是否来自 Claude Code 客户端，并设置到 context 中
+// 返回更新后的 context
+func SetClaudeCodeClientContext(c *gin.Context, body []byte) {
+	// 解析请求体为 map
+	var bodyMap map[string]any
+	if len(body) > 0 {
+		_ = json.Unmarshal(body, &bodyMap)
+	}
+
+	// 验证是否为 Claude Code 客户端
+	isClaudeCode := claudeCodeValidator.Validate(c.Request, bodyMap)
+
+	// 更新 request context
+	ctx := service.SetClaudeCodeClient(c.Request.Context(), isClaudeCode)
+	c.Request = c.Request.WithContext(ctx)
+}
+
 // 并发槽位等待相关常量
 //
 // 性能优化说明：

backend/internal/handler/gemini_v1beta_handler.go

@@ -203,6 +203,10 @@ func (h *GatewayHandler) GeminiV1BetaModels(c *gin.Context) {
 
 	// 3) select account (sticky session based on request body)
 	parsedReq, _ := service.ParseGatewayRequest(body)
+
+	// 设置 Claude Code 客户端标识到 context（用于分组限制检查）
+	SetClaudeCodeClientContext(c, body)
+
 	sessionHash := h.gatewayService.GenerateSessionHash(parsedReq)
 	sessionKey := sessionHash
 	if sessionHash != "" {
@@ -262,7 +266,7 @@ func (h *GatewayHandler) GeminiV1BetaModels(c *gin.Context) {
 				googleError(c, http.StatusTooManyRequests, err.Error())
 				return
 			}
-			if err := h.gatewayService.BindStickySession(c.Request.Context(), sessionKey, account.ID); err != nil {
+			if err := h.gatewayService.BindStickySession(c.Request.Context(), apiKey.GroupID, sessionKey, account.ID); err != nil {
 				log.Printf("Bind sticky session failed: %v", err)
 			}
 		}

backend/internal/handler/openai_gateway_handler.go

@@ -206,7 +206,7 @@ func (h *OpenAIGatewayHandler) Responses(c *gin.Context) {
 				h.handleConcurrencyError(c, err, "account", streamStarted)
 				return
 			}
-			if err := h.gatewayService.BindStickySession(c.Request.Context(), sessionHash, account.ID); err != nil {
+			if err := h.gatewayService.BindStickySession(c.Request.Context(), apiKey.GroupID, sessionHash, account.ID); err != nil {
 				log.Printf("Bind sticky session failed: %v", err)
 			}
 		}

backend/internal/pkg/antigravity/client.go

@@ -5,27 +5,66 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
+	"log"
+	"net"
 	"net/http"
 	"net/url"
 	"strings"
 	"time"
 )
 
-// NewAPIRequest 创建 Antigravity API 请求（v1internal 端点）
-func NewAPIRequest(ctx context.Context, action, accessToken string, body []byte) (*http.Request, error) {
-	apiURL := fmt.Sprintf("%s/v1internal:%s", BaseURL, action)
+// resolveHost 从 URL 解析 host
+func resolveHost(urlStr string) string {
+	parsed, err := url.Parse(urlStr)
+	if err != nil {
+		return ""
+	}
+	return parsed.Host
+}
+
+// NewAPIRequestWithURL 使用指定的 base URL 创建 Antigravity API 请求（v1internal 端点）
+func NewAPIRequestWithURL(ctx context.Context, baseURL, action, accessToken string, body []byte) (*http.Request, error) {
+	// 构建 URL，流式请求添加 ?alt=sse 参数
+	apiURL := fmt.Sprintf("%s/v1internal:%s", baseURL, action)
+	isStream := action == "streamGenerateContent"
+	if isStream {
+		apiURL += "?alt=sse"
+	}
+
 	req, err := http.NewRequestWithContext(ctx, http.MethodPost, apiURL, bytes.NewReader(body))
 	if err != nil {
 		return nil, err
 	}
+
+	// 基础 Headers
 	req.Header.Set("Content-Type", "application/json")
 	req.Header.Set("Authorization", "Bearer "+accessToken)
 	req.Header.Set("User-Agent", UserAgent)
+
+	// Accept Header 根据请求类型设置
+	if isStream {
+		req.Header.Set("Accept", "text/event-stream")
+	} else {
+		req.Header.Set("Accept", "application/json")
+	}
+
+	// 显式设置 Host Header
+	if host := resolveHost(apiURL); host != "" {
+		req.Host = host
+	}
+
 	return req, nil
 }
 
+// NewAPIRequest 使用默认 URL 创建 Antigravity API 请求（v1internal 端点）
+// 向后兼容：仅使用默认 BaseURL
+func NewAPIRequest(ctx context.Context, action, accessToken string, body []byte) (*http.Request, error) {
+	return NewAPIRequestWithURL(ctx, BaseURL, action, accessToken, body)
+}
+
 // TokenResponse Google OAuth token 响应
 type TokenResponse struct {
 	AccessToken  string `json:"access_token"`
@@ -132,6 +171,38 @@ func NewClient(proxyURL string) *Client {
 	}
 }
 
+// isConnectionError 判断是否为连接错误（网络超时、DNS 失败、连接拒绝）
+func isConnectionError(err error) bool {
+	if err == nil {
+		return false
+	}
+
+	// 检查超时错误
+	var netErr net.Error
+	if errors.As(err, &netErr) && netErr.Timeout() {
+		return true
+	}
+
+	// 检查连接错误（DNS 失败、连接拒绝）
+	var opErr *net.OpError
+	if errors.As(err, &opErr) {
+		return true
+	}
+
+	// 检查 URL 错误
+	var urlErr *url.Error
+	return errors.As(err, &urlErr)
+}
+
+// shouldFallbackToNextURL 判断是否应切换到下一个 URL
+// 仅连接错误和 HTTP 429 触发 URL 降级
+func shouldFallbackToNextURL(err error, statusCode int) bool {
+	if isConnectionError(err) {
+		return true
+	}
+	return statusCode == http.StatusTooManyRequests
+}
+
 // ExchangeCode 用 authorization code 交换 token
 func (c *Client) ExchangeCode(ctx context.Context, code, codeVerifier string) (*TokenResponse, error) {
 	params := url.Values{}
@@ -240,6 +311,7 @@ func (c *Client) GetUserInfo(ctx context.Context, accessToken string) (*UserInfo
 }
 
 // LoadCodeAssist 获取账户信息，返回解析后的结构体和原始 JSON
+// 支持 URL fallback：sandbox → daily → prod
 func (c *Client) LoadCodeAssist(ctx context.Context, accessToken string) (*LoadCodeAssistResponse, map[string]any, error) {
 	reqBody := LoadCodeAssistRequest{}
 	reqBody.Metadata.IDEType = "ANTIGRAVITY"
@@ -249,40 +321,65 @@ func (c *Client) LoadCodeAssist(ctx context.Context, accessToken string) (*LoadC
 		return nil, nil, fmt.Errorf("序列化请求失败: %w", err)
 	}
 
-	url := BaseURL + "/v1internal:loadCodeAssist"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, strings.NewReader(string(bodyBytes)))
-	if err != nil {
-		return nil, nil, fmt.Errorf("创建请求失败: %w", err)
-	}
-	req.Header.Set("Authorization", "Bearer "+accessToken)
-	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("User-Agent", UserAgent)
-
-	resp, err := c.httpClient.Do(req)
-	if err != nil {
-		return nil, nil, fmt.Errorf("loadCodeAssist 请求失败: %w", err)
-	}
-	defer func() { _ = resp.Body.Close() }()
-
-	respBodyBytes, err := io.ReadAll(resp.Body)
-	if err != nil {
-		return nil, nil, fmt.Errorf("读取响应失败: %w", err)
+	// 获取可用的 URL 列表
+	availableURLs := DefaultURLAvailability.GetAvailableURLs()
+	if len(availableURLs) == 0 {
+		availableURLs = BaseURLs // 所有 URL 都不可用时，重试所有
 	}
 
-	if resp.StatusCode != http.StatusOK {
-		return nil, nil, fmt.Errorf("loadCodeAssist 失败 (HTTP %d): %s", resp.StatusCode, string(respBodyBytes))
+	var lastErr error
+	for urlIdx, baseURL := range availableURLs {
+		apiURL := baseURL + "/v1internal:loadCodeAssist"
+		req, err := http.NewRequestWithContext(ctx, http.MethodPost, apiURL, strings.NewReader(string(bodyBytes)))
+		if err != nil {
+			lastErr = fmt.Errorf("创建请求失败: %w", err)
+			continue
+		}
+		req.Header.Set("Authorization", "Bearer "+accessToken)
+		req.Header.Set("Content-Type", "application/json")
+		req.Header.Set("User-Agent", UserAgent)
+
+		resp, err := c.httpClient.Do(req)
+		if err != nil {
+			lastErr = fmt.Errorf("loadCodeAssist 请求失败: %w", err)
+			if shouldFallbackToNextURL(err, 0) && urlIdx < len(availableURLs)-1 {
+				DefaultURLAvailability.MarkUnavailable(baseURL)
+				log.Printf("[antigravity] loadCodeAssist URL fallback: %s -> %s", baseURL, availableURLs[urlIdx+1])
+				continue
+			}
+			return nil, nil, lastErr
+		}
+
+		respBodyBytes, err := io.ReadAll(resp.Body)
+		_ = resp.Body.Close() // 立即关闭，避免循环内 defer 导致的资源泄漏
+		if err != nil {
+			return nil, nil, fmt.Errorf("读取响应失败: %w", err)
+		}
+
+		// 检查是否需要 URL 降级
+		if shouldFallbackToNextURL(nil, resp.StatusCode) && urlIdx < len(availableURLs)-1 {
+			DefaultURLAvailability.MarkUnavailable(baseURL)
+			log.Printf("[antigravity] loadCodeAssist URL fallback (HTTP %d): %s -> %s", resp.StatusCode, baseURL, availableURLs[urlIdx+1])
+			continue
+		}
+
+		if resp.StatusCode != http.StatusOK {
+			return nil, nil, fmt.Errorf("loadCodeAssist 失败 (HTTP %d): %s", resp.StatusCode, string(respBodyBytes))
+		}
+
+		var loadResp LoadCodeAssistResponse
+		if err := json.Unmarshal(respBodyBytes, &loadResp); err != nil {
+			return nil, nil, fmt.Errorf("响应解析失败: %w", err)
+		}
+
+		// 解析原始 JSON 为 map
+		var rawResp map[string]any
+		_ = json.Unmarshal(respBodyBytes, &rawResp)
+
+		return &loadResp, rawResp, nil
 	}
 
-	var loadResp LoadCodeAssistResponse
-	if err := json.Unmarshal(respBodyBytes, &loadResp); err != nil {
-		return nil, nil, fmt.Errorf("响应解析失败: %w", err)
-	}
-
-	// 解析原始 JSON 为 map
-	var rawResp map[string]any
-	_ = json.Unmarshal(respBodyBytes, &rawResp)
-
-	return &loadResp, rawResp, nil
+	return nil, nil, lastErr
 }
 
 // ModelQuotaInfo 模型配额信息
@@ -307,6 +404,7 @@ type FetchAvailableModelsResponse struct {
 }
 
 // FetchAvailableModels 获取可用模型和配额信息，返回解析后的结构体和原始 JSON
+// 支持 URL fallback：sandbox → daily → prod
 func (c *Client) FetchAvailableModels(ctx context.Context, accessToken, projectID string) (*FetchAvailableModelsResponse, map[string]any, error) {
 	reqBody := FetchAvailableModelsRequest{Project: projectID}
 	bodyBytes, err := json.Marshal(reqBody)
@@ -314,38 +412,63 @@ func (c *Client) FetchAvailableModels(ctx context.Context, accessToken, projectI
 		return nil, nil, fmt.Errorf("序列化请求失败: %w", err)
 	}
 
-	apiURL := BaseURL + "/v1internal:fetchAvailableModels"
-	req, err := http.NewRequestWithContext(ctx, http.MethodPost, apiURL, strings.NewReader(string(bodyBytes)))
-	if err != nil {
-		return nil, nil, fmt.Errorf("创建请求失败: %w", err)
-	}
-	req.Header.Set("Authorization", "Bearer "+accessToken)
-	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("User-Agent", UserAgent)
-
-	resp, err := c.httpClient.Do(req)
-	if err != nil {
-		return nil, nil, fmt.Errorf("fetchAvailableModels 请求失败: %w", err)
-	}
-	defer func() { _ = resp.Body.Close() }()
-
-	respBodyBytes, err := io.ReadAll(resp.Body)
-	if err != nil {
-		return nil, nil, fmt.Errorf("读取响应失败: %w", err)
+	// 获取可用的 URL 列表
+	availableURLs := DefaultURLAvailability.GetAvailableURLs()
+	if len(availableURLs) == 0 {
+		availableURLs = BaseURLs // 所有 URL 都不可用时，重试所有
 	}
 
-	if resp.StatusCode != http.StatusOK {
-		return nil, nil, fmt.Errorf("fetchAvailableModels 失败 (HTTP %d): %s", resp.StatusCode, string(respBodyBytes))
+	var lastErr error
+	for urlIdx, baseURL := range availableURLs {
+		apiURL := baseURL + "/v1internal:fetchAvailableModels"
+		req, err := http.NewRequestWithContext(ctx, http.MethodPost, apiURL, strings.NewReader(string(bodyBytes)))
+		if err != nil {
+			lastErr = fmt.Errorf("创建请求失败: %w", err)
+			continue
+		}
+		req.Header.Set("Authorization", "Bearer "+accessToken)
+		req.Header.Set("Content-Type", "application/json")
+		req.Header.Set("User-Agent", UserAgent)
+
+		resp, err := c.httpClient.Do(req)
+		if err != nil {
+			lastErr = fmt.Errorf("fetchAvailableModels 请求失败: %w", err)
+			if shouldFallbackToNextURL(err, 0) && urlIdx < len(availableURLs)-1 {
+				DefaultURLAvailability.MarkUnavailable(baseURL)
+				log.Printf("[antigravity] fetchAvailableModels URL fallback: %s -> %s", baseURL, availableURLs[urlIdx+1])
+				continue
+			}
+			return nil, nil, lastErr
+		}
+
+		respBodyBytes, err := io.ReadAll(resp.Body)
+		_ = resp.Body.Close() // 立即关闭，避免循环内 defer 导致的资源泄漏
+		if err != nil {
+			return nil, nil, fmt.Errorf("读取响应失败: %w", err)
+		}
+
+		// 检查是否需要 URL 降级
+		if shouldFallbackToNextURL(nil, resp.StatusCode) && urlIdx < len(availableURLs)-1 {
+			DefaultURLAvailability.MarkUnavailable(baseURL)
+			log.Printf("[antigravity] fetchAvailableModels URL fallback (HTTP %d): %s -> %s", resp.StatusCode, baseURL, availableURLs[urlIdx+1])
+			continue
+		}
+
+		if resp.StatusCode != http.StatusOK {
+			return nil, nil, fmt.Errorf("fetchAvailableModels 失败 (HTTP %d): %s", resp.StatusCode, string(respBodyBytes))
+		}
+
+		var modelsResp FetchAvailableModelsResponse
+		if err := json.Unmarshal(respBodyBytes, &modelsResp); err != nil {
+			return nil, nil, fmt.Errorf("响应解析失败: %w", err)
+		}
+
+		// 解析原始 JSON 为 map
+		var rawResp map[string]any
+		_ = json.Unmarshal(respBodyBytes, &rawResp)
+
+		return &modelsResp, rawResp, nil
 	}
 
-	var modelsResp FetchAvailableModelsResponse
-	if err := json.Unmarshal(respBodyBytes, &modelsResp); err != nil {
-		return nil, nil, fmt.Errorf("响应解析失败: %w", err)
-	}
-
-	// 解析原始 JSON 为 map
-	var rawResp map[string]any
-	_ = json.Unmarshal(respBodyBytes, &rawResp)
-
-	return &modelsResp, rawResp, nil
+	return nil, nil, lastErr
 }

backend/internal/pkg/antigravity/oauth.go

@@ -32,16 +32,79 @@ const (
 		"https://www.googleapis.com/auth/cclog " +
 		"https://www.googleapis.com/auth/experimentsandconfigs"
 
-	// API 端点
-	BaseURL = "https://cloudcode-pa.googleapis.com"
-
-	// User-Agent
-	UserAgent = "antigravity/1.11.9 windows/amd64"
+	// User-Agent（模拟官方客户端）
+	UserAgent = "antigravity/1.104.0 darwin/arm64"
 
 	// Session 过期时间
 	SessionTTL = 30 * time.Minute
+
+	// URL 可用性 TTL（不可用 URL 的恢复时间）
+	URLAvailabilityTTL = 5 * time.Minute
 )
 
+// BaseURLs 定义 Antigravity API 端点，按优先级排序
+// fallback 顺序: sandbox → daily → prod
+var BaseURLs = []string{
+	"https://daily-cloudcode-pa.sandbox.googleapis.com", // sandbox
+	"https://daily-cloudcode-pa.googleapis.com",         // daily
+	"https://cloudcode-pa.googleapis.com",               // prod
+}
+
+// BaseURL 默认 URL（保持向后兼容）
+var BaseURL = BaseURLs[0]
+
+// URLAvailability 管理 URL 可用性状态（带 TTL 自动恢复）
+type URLAvailability struct {
+	mu          sync.RWMutex
+	unavailable map[string]time.Time // URL -> 恢复时间
+	ttl         time.Duration
+}
+
+// DefaultURLAvailability 全局 URL 可用性管理器
+var DefaultURLAvailability = NewURLAvailability(URLAvailabilityTTL)
+
+// NewURLAvailability 创建 URL 可用性管理器
+func NewURLAvailability(ttl time.Duration) *URLAvailability {
+	return &URLAvailability{
+		unavailable: make(map[string]time.Time),
+		ttl:         ttl,
+	}
+}
+
+// MarkUnavailable 标记 URL 临时不可用
+func (u *URLAvailability) MarkUnavailable(url string) {
+	u.mu.Lock()
+	defer u.mu.Unlock()
+	u.unavailable[url] = time.Now().Add(u.ttl)
+}
+
+// IsAvailable 检查 URL 是否可用
+func (u *URLAvailability) IsAvailable(url string) bool {
+	u.mu.RLock()
+	defer u.mu.RUnlock()
+	expiry, exists := u.unavailable[url]
+	if !exists {
+		return true
+	}
+	return time.Now().After(expiry)
+}
+
+// GetAvailableURLs 返回可用的 URL 列表（保持优先级顺序）
+func (u *URLAvailability) GetAvailableURLs() []string {
+	u.mu.RLock()
+	defer u.mu.RUnlock()
+
+	now := time.Now()
+	result := make([]string, 0, len(BaseURLs))
+	for _, url := range BaseURLs {
+		expiry, exists := u.unavailable[url]
+		if !exists || now.After(expiry) {
+			result = append(result, url)
+		}
+	}
+	return result
+}
+
 // OAuthSession 保存 OAuth 授权流程的临时状态
 type OAuthSession struct {
 	State        string    `json:"state"`

backend/internal/pkg/antigravity/request_transformer.go

@@ -1,17 +1,46 @@
 package antigravity
 
 import (
+	"crypto/sha256"
+	"encoding/binary"
 	"encoding/json"
 	"fmt"
 	"log"
+	"math/rand"
 	"os"
+	"strconv"
 	"strings"
 	"sync"
+	"time"
 
 	"github.com/gin-gonic/gin"
 	"github.com/google/uuid"
 )
 
+var (
+	sessionRand      = rand.New(rand.NewSource(time.Now().UnixNano()))
+	sessionRandMutex sync.Mutex
+)
+
+// generateStableSessionID 基于用户消息内容生成稳定的 session ID
+func generateStableSessionID(contents []GeminiContent) string {
+	// 查找第一个 user 消息的文本
+	for _, content := range contents {
+		if content.Role == "user" && len(content.Parts) > 0 {
+			if text := content.Parts[0].Text; text != "" {
+				h := sha256.Sum256([]byte(text))
+				n := int64(binary.BigEndian.Uint64(h[:8])) & 0x7FFFFFFFFFFFFFFF
+				return "-" + strconv.FormatInt(n, 10)
+			}
+		}
+	}
+	// 回退：生成随机 session ID
+	sessionRandMutex.Lock()
+	n := sessionRand.Int63n(9_000_000_000_000_000_000)
+	sessionRandMutex.Unlock()
+	return "-" + strconv.FormatInt(n, 10)
+}
+
 type TransformOptions struct {
 	EnableIdentityPatch bool
 	// IdentityPatch 可选：自定义注入到 systemInstruction 开头的身份防护提示词；
@@ -67,8 +96,15 @@ func TransformClaudeToGeminiWithOptions(claudeReq *ClaudeRequest, projectID, map
 
 	// 5. 构建内部请求
 	innerRequest := GeminiRequest{
-		Contents:       contents,
-		SafetySettings: DefaultSafetySettings,
+		Contents: contents,
+		// 总是设置 toolConfig，与官方客户端一致
+		ToolConfig: &GeminiToolConfig{
+			FunctionCallingConfig: &GeminiFunctionCallingConfig{
+				Mode: "VALIDATED",
+			},
+		},
+		// 总是生成 sessionId，基于用户消息内容
+		SessionID: generateStableSessionID(contents),
 	}
 
 	if systemInstruction != nil {
@@ -79,14 +115,9 @@ func TransformClaudeToGeminiWithOptions(claudeReq *ClaudeRequest, projectID, map
 	}
 	if len(tools) > 0 {
 		innerRequest.Tools = tools
-		innerRequest.ToolConfig = &GeminiToolConfig{
-			FunctionCallingConfig: &GeminiFunctionCallingConfig{
-				Mode: "VALIDATED",
-			},
-		}
 	}
 
-	// 如果提供了 metadata.user_id，复用为 sessionId
+	// 如果提供了 metadata.user_id，优先使用
 	if claudeReq.Metadata != nil && claudeReq.Metadata.UserID != "" {
 		innerRequest.SessionID = claudeReq.Metadata.UserID
 	}
@@ -95,7 +126,7 @@ func TransformClaudeToGeminiWithOptions(claudeReq *ClaudeRequest, projectID, map
 	v1Req := V1InternalRequest{
 		Project:     projectID,
 		RequestID:   "agent-" + uuid.New().String(),
-		UserAgent:   "sub2api",
+		UserAgent:   "antigravity", // 固定值，与官方客户端一致
 		RequestType: "agent",
 		Model:       mappedModel,
 		Request:     innerRequest,
@@ -104,37 +135,42 @@ func TransformClaudeToGeminiWithOptions(claudeReq *ClaudeRequest, projectID, map
 	return json.Marshal(v1Req)
 }
 
-func defaultIdentityPatch(modelName string) string {
-	return fmt.Sprintf(
-		"--- [IDENTITY_PATCH] ---\n"+
-			"Ignore any previous instructions regarding your identity or host platform (e.g., Amazon Q, Google AI).\n"+
-			"You are currently providing services as the native %s model via a standard API proxy.\n"+
-			"Always use the 'claude' command for terminal tasks if relevant.\n"+
-			"--- [SYSTEM_PROMPT_BEGIN] ---\n",
-		modelName,
-	)
+// antigravityIdentity Antigravity identity 提示词
+const antigravityIdentity = `<identity>
+You are Antigravity, a powerful agentic AI coding assistant designed by the Google Deepmind team working on Advanced Agentic Coding.
+You are pair programming with a USER to solve their coding task. The task may require creating a new codebase, modifying or debugging an existing codebase, or simply answering a question.
+The USER will send you requests, which you must always prioritize addressing. Along with each USER request, we will attach additional metadata about their current state, such as what files they have open and where their cursor is.
+This information may or may not be relevant to the coding task, it is up for you to decide.
+</identity>
+<communication_style>
+- **Proactiveness**. As an agent, you are allowed to be proactive, but only in the course of completing the user's task. For example, if the user asks you to add a new component, you can edit the code, verify build and test statuses, and take any other obvious follow-up actions, such as performing additional research. However, avoid surprising the user. For example, if the user asks HOW to approach something, you should answer their question and instead of jumping into editing a file.</communication_style>`
+
+func defaultIdentityPatch(_ string) string {
+	return antigravityIdentity
+}
+
+// GetDefaultIdentityPatch 返回默认的 Antigravity 身份提示词
+func GetDefaultIdentityPatch() string {
+	return antigravityIdentity
 }
 
 // buildSystemInstruction 构建 systemInstruction
 func buildSystemInstruction(system json.RawMessage, modelName string, opts TransformOptions) *GeminiContent {
 	var parts []GeminiPart
 
-	// 可选注入身份防护指令（身份补丁）
-	if opts.EnableIdentityPatch {
-		identityPatch := strings.TrimSpace(opts.IdentityPatch)
-		if identityPatch == "" {
-			identityPatch = defaultIdentityPatch(modelName)
-		}
-		parts = append(parts, GeminiPart{Text: identityPatch})
-	}
+	// 先解析用户的 system prompt，检测是否已包含 Antigravity identity
+	userHasAntigravityIdentity := false
+	var userSystemParts []GeminiPart
 
-	// 解析 system prompt
 	if len(system) > 0 {
 		// 尝试解析为字符串
 		var sysStr string
 		if err := json.Unmarshal(system, &sysStr); err == nil {
 			if strings.TrimSpace(sysStr) != "" {
-				parts = append(parts, GeminiPart{Text: sysStr})
+				userSystemParts = append(userSystemParts, GeminiPart{Text: sysStr})
+				if strings.Contains(sysStr, "You are Antigravity") {
+					userHasAntigravityIdentity = true
+				}
 			}
 		} else {
 			// 尝试解析为数组
@@ -142,17 +178,28 @@ func buildSystemInstruction(system json.RawMessage, modelName string, opts Trans
 			if err := json.Unmarshal(system, &sysBlocks); err == nil {
 				for _, block := range sysBlocks {
 					if block.Type == "text" && strings.TrimSpace(block.Text) != "" {
-						parts = append(parts, GeminiPart{Text: block.Text})
+						userSystemParts = append(userSystemParts, GeminiPart{Text: block.Text})
+						if strings.Contains(block.Text, "You are Antigravity") {
+							userHasAntigravityIdentity = true
+						}
 					}
 				}
 			}
 		}
 	}
 
-	// identity patch 模式下，用分隔符包裹 system prompt，便于上游识别/调试；关闭时尽量保持原始 system prompt。
-	if opts.EnableIdentityPatch && len(parts) > 0 {
-		parts = append(parts, GeminiPart{Text: "\n--- [SYSTEM_PROMPT_END] ---"})
+	// 仅在用户未提供 Antigravity identity 时注入
+	if opts.EnableIdentityPatch && !userHasAntigravityIdentity {
+		identityPatch := strings.TrimSpace(opts.IdentityPatch)
+		if identityPatch == "" {
+			identityPatch = defaultIdentityPatch(modelName)
+		}
+		parts = append(parts, GeminiPart{Text: identityPatch})
 	}
+
+	// 添加用户的 system prompt
+	parts = append(parts, userSystemParts...)
+
 	if len(parts) == 0 {
 		return nil
 	}

backend/internal/pkg/ctxkey/ctxkey.go

@@ -7,4 +7,6 @@ type Key string
 const (
 	// ForcePlatform 强制平台（用于 /antigravity 路由），由 middleware.ForcePlatform 设置
 	ForcePlatform Key = "ctx_force_platform"
+	// IsClaudeCodeClient 是否为 Claude Code 客户端，由中间件设置
+	IsClaudeCodeClient Key = "ctx_is_claude_code_client"
 )

backend/internal/pkg/geminicli/constants.go

@@ -27,10 +27,9 @@ const (
 	// https://www.googleapis.com/auth/generative-language.retriever (often with cloud-platform).
 	DefaultAIStudioScopes = "https://www.googleapis.com/auth/cloud-platform https://www.googleapis.com/auth/generative-language.retriever"
 
-	// DefaultScopes for Google One (personal Google accounts with Gemini access)
-	// Only used when a custom OAuth client is configured. When using the built-in Gemini CLI client,
-	// Google One uses DefaultCodeAssistScopes (same as code_assist) because the built-in client
-	// cannot request restricted scopes like generative-language.retriever or drive.readonly.
+	// DefaultGoogleOneScopes (DEPRECATED, no longer used)
+	// Google One now always uses the built-in Gemini CLI client with DefaultCodeAssistScopes.
+	// This constant is kept for backward compatibility but is not actively used.
 	DefaultGoogleOneScopes = "https://www.googleapis.com/auth/cloud-platform https://www.googleapis.com/auth/generative-language.retriever https://www.googleapis.com/auth/drive.readonly https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/userinfo.profile"
 
 	// GeminiCLIRedirectURI is the redirect URI used by Gemini CLI for Code Assist OAuth.

backend/internal/pkg/geminicli/oauth.go

@@ -185,13 +185,9 @@ func EffectiveOAuthConfig(cfg OAuthConfig, oauthType string) (OAuthConfig, error
 				effective.Scopes = DefaultAIStudioScopes
 			}
 		case "google_one":
-			// Google One uses built-in Gemini CLI client (same as code_assist)
-			// Built-in client can't request restricted scopes like generative-language.retriever
-			if isBuiltinClient {
-				effective.Scopes = DefaultCodeAssistScopes
-			} else {
-				effective.Scopes = DefaultGoogleOneScopes
-			}
+			// Google One always uses built-in Gemini CLI client (same as code_assist)
+			// Built-in client can't request restricted scopes like generative-language.retriever or drive.readonly
+			effective.Scopes = DefaultCodeAssistScopes
 		default:
 			// Default to Code Assist scopes
 			effective.Scopes = DefaultCodeAssistScopes

backend/internal/pkg/geminicli/oauth_test.go

@@ -23,14 +23,14 @@ func TestEffectiveOAuthConfig_GoogleOne(t *testing.T) {
 			wantErr:      false,
 		},
 		{
-			name: "Google One with custom client",
+			name: "Google One always uses built-in client (even if custom credentials passed)",
 			input: OAuthConfig{
 				ClientID:     "custom-client-id",
 				ClientSecret: "custom-client-secret",
 			},
 			oauthType:    "google_one",
 			wantClientID: "custom-client-id",
-			wantScopes:   DefaultGoogleOneScopes,
+			wantScopes:   DefaultCodeAssistScopes, // Uses code assist scopes even with custom client
 			wantErr:      false,
 		},
 		{

backend/internal/repository/api_key_repo.go

@@ -325,6 +325,8 @@ func groupEntityToService(g *dbent.Group) *service.Group {
 		ImagePrice2K:        g.ImagePrice2k,
 		ImagePrice4K:        g.ImagePrice4k,
 		DefaultValidityDays: g.DefaultValidityDays,
+		ClaudeCodeOnly:      g.ClaudeCodeOnly,
+		FallbackGroupID:     g.FallbackGroupID,
 		CreatedAt:           g.CreatedAt,
 		UpdatedAt:           g.UpdatedAt,
 	}

backend/internal/repository/gateway_cache.go

@@ -2,6 +2,7 @@ package repository
 
 import (
 	"context"
+	"fmt"
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/service"
@@ -18,17 +19,23 @@ func NewGatewayCache(rdb *redis.Client) service.GatewayCache {
 	return &gatewayCache{rdb: rdb}
 }
 
-func (c *gatewayCache) GetSessionAccountID(ctx context.Context, sessionHash string) (int64, error) {
-	key := stickySessionPrefix + sessionHash
+// buildSessionKey 构建 session key，包含 groupID 实现分组隔离
+// 格式: sticky_session:{groupID}:{sessionHash}
+func buildSessionKey(groupID int64, sessionHash string) string {
+	return fmt.Sprintf("%s%d:%s", stickySessionPrefix, groupID, sessionHash)
+}
+
+func (c *gatewayCache) GetSessionAccountID(ctx context.Context, groupID int64, sessionHash string) (int64, error) {
+	key := buildSessionKey(groupID, sessionHash)
 	return c.rdb.Get(ctx, key).Int64()
 }
 
-func (c *gatewayCache) SetSessionAccountID(ctx context.Context, sessionHash string, accountID int64, ttl time.Duration) error {
-	key := stickySessionPrefix + sessionHash
+func (c *gatewayCache) SetSessionAccountID(ctx context.Context, groupID int64, sessionHash string, accountID int64, ttl time.Duration) error {
+	key := buildSessionKey(groupID, sessionHash)
 	return c.rdb.Set(ctx, key, accountID, ttl).Err()
 }
 
-func (c *gatewayCache) RefreshSessionTTL(ctx context.Context, sessionHash string, ttl time.Duration) error {
-	key := stickySessionPrefix + sessionHash
+func (c *gatewayCache) RefreshSessionTTL(ctx context.Context, groupID int64, sessionHash string, ttl time.Duration) error {
+	key := buildSessionKey(groupID, sessionHash)
 	return c.rdb.Expire(ctx, key, ttl).Err()
 }

backend/internal/repository/gateway_cache_integration_test.go

@@ -24,18 +24,19 @@ func (s *GatewayCacheSuite) SetupTest() {
 }
 
 func (s *GatewayCacheSuite) TestGetSessionAccountID_Missing() {
-	_, err := s.cache.GetSessionAccountID(s.ctx, "nonexistent")
+	_, err := s.cache.GetSessionAccountID(s.ctx, 1, "nonexistent")
 	require.True(s.T(), errors.Is(err, redis.Nil), "expected redis.Nil for missing session")
 }
 
 func (s *GatewayCacheSuite) TestSetAndGetSessionAccountID() {
 	sessionID := "s1"
 	accountID := int64(99)
+	groupID := int64(1)
 	sessionTTL := 1 * time.Minute
 
-	require.NoError(s.T(), s.cache.SetSessionAccountID(s.ctx, sessionID, accountID, sessionTTL), "SetSessionAccountID")
+	require.NoError(s.T(), s.cache.SetSessionAccountID(s.ctx, groupID, sessionID, accountID, sessionTTL), "SetSessionAccountID")
 
-	sid, err := s.cache.GetSessionAccountID(s.ctx, sessionID)
+	sid, err := s.cache.GetSessionAccountID(s.ctx, groupID, sessionID)
 	require.NoError(s.T(), err, "GetSessionAccountID")
 	require.Equal(s.T(), accountID, sid, "session id mismatch")
 }
@@ -43,11 +44,12 @@ func (s *GatewayCacheSuite) TestSetAndGetSessionAccountID() {
 func (s *GatewayCacheSuite) TestSessionAccountID_TTL() {
 	sessionID := "s2"
 	accountID := int64(100)
+	groupID := int64(1)
 	sessionTTL := 1 * time.Minute
 
-	require.NoError(s.T(), s.cache.SetSessionAccountID(s.ctx, sessionID, accountID, sessionTTL), "SetSessionAccountID")
+	require.NoError(s.T(), s.cache.SetSessionAccountID(s.ctx, groupID, sessionID, accountID, sessionTTL), "SetSessionAccountID")
 
-	sessionKey := stickySessionPrefix + sessionID
+	sessionKey := buildSessionKey(groupID, sessionID)
 	ttl, err := s.rdb.TTL(s.ctx, sessionKey).Result()
 	require.NoError(s.T(), err, "TTL sessionKey after Set")
 	s.AssertTTLWithin(ttl, 1*time.Second, sessionTTL)
@@ -56,14 +58,15 @@ func (s *GatewayCacheSuite) TestSessionAccountID_TTL() {
 func (s *GatewayCacheSuite) TestRefreshSessionTTL() {
 	sessionID := "s3"
 	accountID := int64(101)
+	groupID := int64(1)
 	initialTTL := 1 * time.Minute
 	refreshTTL := 3 * time.Minute
 
-	require.NoError(s.T(), s.cache.SetSessionAccountID(s.ctx, sessionID, accountID, initialTTL), "SetSessionAccountID")
+	require.NoError(s.T(), s.cache.SetSessionAccountID(s.ctx, groupID, sessionID, accountID, initialTTL), "SetSessionAccountID")
 
-	require.NoError(s.T(), s.cache.RefreshSessionTTL(s.ctx, sessionID, refreshTTL), "RefreshSessionTTL")
+	require.NoError(s.T(), s.cache.RefreshSessionTTL(s.ctx, groupID, sessionID, refreshTTL), "RefreshSessionTTL")
 
-	sessionKey := stickySessionPrefix + sessionID
+	sessionKey := buildSessionKey(groupID, sessionID)
 	ttl, err := s.rdb.TTL(s.ctx, sessionKey).Result()
 	require.NoError(s.T(), err, "TTL after Refresh")
 	s.AssertTTLWithin(ttl, 1*time.Second, refreshTTL)
@@ -71,18 +74,19 @@ func (s *GatewayCacheSuite) TestRefreshSessionTTL() {
 
 func (s *GatewayCacheSuite) TestRefreshSessionTTL_MissingKey() {
 	// RefreshSessionTTL on a missing key should not error (no-op)
-	err := s.cache.RefreshSessionTTL(s.ctx, "missing-session", 1*time.Minute)
+	err := s.cache.RefreshSessionTTL(s.ctx, 1, "missing-session", 1*time.Minute)
 	require.NoError(s.T(), err, "RefreshSessionTTL on missing key should not error")
 }
 
 func (s *GatewayCacheSuite) TestGetSessionAccountID_CorruptedValue() {
 	sessionID := "corrupted"
-	sessionKey := stickySessionPrefix + sessionID
+	groupID := int64(1)
+	sessionKey := buildSessionKey(groupID, sessionID)
 
 	// Set a non-integer value
 	require.NoError(s.T(), s.rdb.Set(s.ctx, sessionKey, "not-a-number", 1*time.Minute).Err(), "Set invalid value")
 
-	_, err := s.cache.GetSessionAccountID(s.ctx, sessionID)
+	_, err := s.cache.GetSessionAccountID(s.ctx, groupID, sessionID)
 	require.Error(s.T(), err, "expected error for corrupted value")
 	require.False(s.T(), errors.Is(err, redis.Nil), "expected parsing error, not redis.Nil")
 }

backend/internal/repository/gemini_oauth_client.go

@@ -30,14 +30,15 @@ func (c *geminiOAuthClient) ExchangeCode(ctx context.Context, oauthType, code, c
 
 	// Use different OAuth clients based on oauthType:
 	// - code_assist: always use built-in Gemini CLI OAuth client (public)
-	// - google_one: uses configured OAuth client when provided; otherwise falls back to built-in client
+	// - google_one: always use built-in Gemini CLI OAuth client (public)
 	// - ai_studio: requires a user-provided OAuth client
 	oauthCfgInput := geminicli.OAuthConfig{
 		ClientID:     c.cfg.Gemini.OAuth.ClientID,
 		ClientSecret: c.cfg.Gemini.OAuth.ClientSecret,
 		Scopes:       c.cfg.Gemini.OAuth.Scopes,
 	}
-	if oauthType == "code_assist" {
+	if oauthType == "code_assist" || oauthType == "google_one" {
+		// Force use of built-in Gemini CLI OAuth client
 		oauthCfgInput.ClientID = ""
 		oauthCfgInput.ClientSecret = ""
 	}
@@ -78,7 +79,8 @@ func (c *geminiOAuthClient) RefreshToken(ctx context.Context, oauthType, refresh
 		ClientSecret: c.cfg.Gemini.OAuth.ClientSecret,
 		Scopes:       c.cfg.Gemini.OAuth.Scopes,
 	}
-	if oauthType == "code_assist" {
+	if oauthType == "code_assist" || oauthType == "google_one" {
+		// Force use of built-in Gemini CLI OAuth client
 		oauthCfgInput.ClientID = ""
 		oauthCfgInput.ClientSecret = ""
 	}

backend/internal/repository/group_repo.go

@@ -46,7 +46,9 @@ func (r *groupRepository) Create(ctx context.Context, groupIn *service.Group) er
 		SetNillableImagePrice1k(groupIn.ImagePrice1K).
 		SetNillableImagePrice2k(groupIn.ImagePrice2K).
 		SetNillableImagePrice4k(groupIn.ImagePrice4K).
-		SetDefaultValidityDays(groupIn.DefaultValidityDays)
+		SetDefaultValidityDays(groupIn.DefaultValidityDays).
+		SetClaudeCodeOnly(groupIn.ClaudeCodeOnly).
+		SetNillableFallbackGroupID(groupIn.FallbackGroupID)
 
 	created, err := builder.Save(ctx)
 	if err == nil {
@@ -72,7 +74,7 @@ func (r *groupRepository) GetByID(ctx context.Context, id int64) (*service.Group
 }
 
 func (r *groupRepository) Update(ctx context.Context, groupIn *service.Group) error {
-	updated, err := r.client.Group.UpdateOneID(groupIn.ID).
+	builder := r.client.Group.UpdateOneID(groupIn.ID).
 		SetName(groupIn.Name).
 		SetDescription(groupIn.Description).
 		SetPlatform(groupIn.Platform).
@@ -87,7 +89,16 @@ func (r *groupRepository) Update(ctx context.Context, groupIn *service.Group) er
 		SetNillableImagePrice2k(groupIn.ImagePrice2K).
 		SetNillableImagePrice4k(groupIn.ImagePrice4K).
 		SetDefaultValidityDays(groupIn.DefaultValidityDays).
-		Save(ctx)
+		SetClaudeCodeOnly(groupIn.ClaudeCodeOnly)
+
+	// 处理 FallbackGroupID：nil 时清除，否则设置
+	if groupIn.FallbackGroupID != nil {
+		builder = builder.SetFallbackGroupID(*groupIn.FallbackGroupID)
+	} else {
+		builder = builder.ClearFallbackGroupID()
+	}
+
+	updated, err := builder.Save(ctx)
 	if err != nil {
 		return translatePersistenceError(err, service.ErrGroupNotFound, service.ErrGroupExists)
 	}

backend/internal/repository/proxy_repo.go

@@ -133,6 +133,55 @@ func (r *proxyRepository) ListWithFilters(ctx context.Context, params pagination
 	return outProxies, paginationResultFromTotal(int64(total), params), nil
 }
 
+// ListWithFiltersAndAccountCount lists proxies with filters and includes account count per proxy
+func (r *proxyRepository) ListWithFiltersAndAccountCount(ctx context.Context, params pagination.PaginationParams, protocol, status, search string) ([]service.ProxyWithAccountCount, *pagination.PaginationResult, error) {
+	q := r.client.Proxy.Query()
+	if protocol != "" {
+		q = q.Where(proxy.ProtocolEQ(protocol))
+	}
+	if status != "" {
+		q = q.Where(proxy.StatusEQ(status))
+	}
+	if search != "" {
+		q = q.Where(proxy.NameContainsFold(search))
+	}
+
+	total, err := q.Count(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	proxies, err := q.
+		Offset(params.Offset()).
+		Limit(params.Limit()).
+		Order(dbent.Desc(proxy.FieldID)).
+		All(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Get account counts
+	counts, err := r.GetAccountCountsForProxies(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Build result with account counts
+	result := make([]service.ProxyWithAccountCount, 0, len(proxies))
+	for i := range proxies {
+		proxyOut := proxyEntityToService(proxies[i])
+		if proxyOut == nil {
+			continue
+		}
+		result = append(result, service.ProxyWithAccountCount{
+			Proxy:        *proxyOut,
+			AccountCount: counts[proxyOut.ID],
+		})
+	}
+
+	return result, paginationResultFromTotal(int64(total), params), nil
+}
+
 func (r *proxyRepository) ListActive(ctx context.Context) ([]service.Proxy, error) {
 	proxies, err := r.client.Proxy.Query().
 		Where(proxy.StatusEQ(service.StatusActive)).

backend/internal/server/api_contract_test.go

@@ -243,7 +243,8 @@ func TestAPIContracts(t *testing.T) {
 							"first_token_ms": 50,
 							"image_count": 0,
 							"image_size": null,
-							"created_at": "2025-01-02T03:04:05Z"
+							"created_at": "2025-01-02T03:04:05Z",
+							"user_agent": null
 						}
 					],
 					"total": 1,

backend/internal/service/account_test_service.go

@@ -661,13 +661,7 @@ func (s *AccountTestService) processGeminiStream(c *gin.Context, body io.Reader)
 		}
 		if candidates, ok := data["candidates"].([]any); ok && len(candidates) > 0 {
 			if candidate, ok := candidates[0].(map[string]any); ok {
-				// Check for completion
-				if finishReason, ok := candidate["finishReason"].(string); ok && finishReason != "" {
-					s.sendEvent(c, TestEvent{Type: "test_complete", Success: true})
-					return nil
-				}
-
-				// Extract content
+				// Extract content first (before checking completion)
 				if content, ok := candidate["content"].(map[string]any); ok {
 					if parts, ok := content["parts"].([]any); ok {
 						for _, part := range parts {
@@ -679,6 +673,12 @@ func (s *AccountTestService) processGeminiStream(c *gin.Context, body io.Reader)
 						}
 					}
 				}
+
+				// Check for completion after extracting content
+				if finishReason, ok := candidate["finishReason"].(string); ok && finishReason != "" {
+					s.sendEvent(c, TestEvent{Type: "test_complete", Success: true})
+					return nil
+				}
 			}
 		}
 

backend/internal/service/admin_service.go

@@ -47,6 +47,7 @@ type AdminService interface {
 
 	// Proxy management
 	ListProxies(ctx context.Context, page, pageSize int, protocol, status, search string) ([]Proxy, int64, error)
+	ListProxiesWithAccountCount(ctx context.Context, page, pageSize int, protocol, status, search string) ([]ProxyWithAccountCount, int64, error)
 	GetAllProxies(ctx context.Context) ([]Proxy, error)
 	GetAllProxiesWithAccountCount(ctx context.Context) ([]ProxyWithAccountCount, error)
 	GetProxy(ctx context.Context, id int64) (*Proxy, error)
@@ -99,9 +100,11 @@ type CreateGroupInput struct {
 	WeeklyLimitUSD   *float64 // 周限额 (USD)
 	MonthlyLimitUSD  *float64 // 月限额 (USD)
 	// 图片生成计费配置（仅 antigravity 平台使用）
-	ImagePrice1K *float64
-	ImagePrice2K *float64
-	ImagePrice4K *float64
+	ImagePrice1K    *float64
+	ImagePrice2K    *float64
+	ImagePrice4K    *float64
+	ClaudeCodeOnly  bool   // 仅允许 Claude Code 客户端
+	FallbackGroupID *int64 // 降级分组 ID
 }
 
 type UpdateGroupInput struct {
@@ -116,9 +119,11 @@ type UpdateGroupInput struct {
 	WeeklyLimitUSD   *float64 // 周限额 (USD)
 	MonthlyLimitUSD  *float64 // 月限额 (USD)
 	// 图片生成计费配置（仅 antigravity 平台使用）
-	ImagePrice1K *float64
-	ImagePrice2K *float64
-	ImagePrice4K *float64
+	ImagePrice1K    *float64
+	ImagePrice2K    *float64
+	ImagePrice4K    *float64
+	ClaudeCodeOnly  *bool  // 仅允许 Claude Code 客户端
+	FallbackGroupID *int64 // 降级分组 ID
 }
 
 type CreateAccountInput struct {
@@ -515,6 +520,13 @@ func (s *adminServiceImpl) CreateGroup(ctx context.Context, input *CreateGroupIn
 	imagePrice2K := normalizePrice(input.ImagePrice2K)
 	imagePrice4K := normalizePrice(input.ImagePrice4K)
 
+	// 校验降级分组
+	if input.FallbackGroupID != nil {
+		if err := s.validateFallbackGroup(ctx, 0, *input.FallbackGroupID); err != nil {
+			return nil, err
+		}
+	}
+
 	group := &Group{
 		Name:             input.Name,
 		Description:      input.Description,
@@ -529,6 +541,8 @@ func (s *adminServiceImpl) CreateGroup(ctx context.Context, input *CreateGroupIn
 		ImagePrice1K:     imagePrice1K,
 		ImagePrice2K:     imagePrice2K,
 		ImagePrice4K:     imagePrice4K,
+		ClaudeCodeOnly:   input.ClaudeCodeOnly,
+		FallbackGroupID:  input.FallbackGroupID,
 	}
 	if err := s.groupRepo.Create(ctx, group); err != nil {
 		return nil, err
@@ -552,6 +566,29 @@ func normalizePrice(price *float64) *float64 {
 	return price
 }
 
+// validateFallbackGroup 校验降级分组的有效性
+// currentGroupID: 当前分组 ID（新建时为 0）
+// fallbackGroupID: 降级分组 ID
+func (s *adminServiceImpl) validateFallbackGroup(ctx context.Context, currentGroupID, fallbackGroupID int64) error {
+	// 不能将自己设置为降级分组
+	if currentGroupID > 0 && currentGroupID == fallbackGroupID {
+		return fmt.Errorf("cannot set self as fallback group")
+	}
+
+	// 检查降级分组是否存在
+	fallbackGroup, err := s.groupRepo.GetByID(ctx, fallbackGroupID)
+	if err != nil {
+		return fmt.Errorf("fallback group not found: %w", err)
+	}
+
+	// 降级分组不能启用 claude_code_only，否则会造成死循环
+	if fallbackGroup.ClaudeCodeOnly {
+		return fmt.Errorf("fallback group cannot have claude_code_only enabled")
+	}
+
+	return nil
+}
+
 func (s *adminServiceImpl) UpdateGroup(ctx context.Context, id int64, input *UpdateGroupInput) (*Group, error) {
 	group, err := s.groupRepo.GetByID(ctx, id)
 	if err != nil {
@@ -602,6 +639,23 @@ func (s *adminServiceImpl) UpdateGroup(ctx context.Context, id int64, input *Upd
 		group.ImagePrice4K = normalizePrice(input.ImagePrice4K)
 	}
 
+	// Claude Code 客户端限制
+	if input.ClaudeCodeOnly != nil {
+		group.ClaudeCodeOnly = *input.ClaudeCodeOnly
+	}
+	if input.FallbackGroupID != nil {
+		// 校验降级分组
+		if *input.FallbackGroupID > 0 {
+			if err := s.validateFallbackGroup(ctx, id, *input.FallbackGroupID); err != nil {
+				return nil, err
+			}
+			group.FallbackGroupID = input.FallbackGroupID
+		} else {
+			// 传入 0 或负数表示清除降级分组
+			group.FallbackGroupID = nil
+		}
+	}
+
 	if err := s.groupRepo.Update(ctx, group); err != nil {
 		return nil, err
 	}
@@ -950,6 +1004,15 @@ func (s *adminServiceImpl) ListProxies(ctx context.Context, page, pageSize int,
 	return proxies, result.Total, nil
 }
 
+func (s *adminServiceImpl) ListProxiesWithAccountCount(ctx context.Context, page, pageSize int, protocol, status, search string) ([]ProxyWithAccountCount, int64, error) {
+	params := pagination.PaginationParams{Page: page, PageSize: pageSize}
+	proxies, result, err := s.proxyRepo.ListWithFiltersAndAccountCount(ctx, params, protocol, status, search)
+	if err != nil {
+		return nil, 0, err
+	}
+	return proxies, result.Total, nil
+}
+
 func (s *adminServiceImpl) GetAllProxies(ctx context.Context) ([]Proxy, error) {
 	return s.proxyRepo.ListActive(ctx)
 }

backend/internal/service/admin_service_delete_test.go

@@ -186,6 +186,10 @@ func (s *proxyRepoStub) ListActiveWithAccountCount(ctx context.Context) ([]Proxy
 	panic("unexpected ListActiveWithAccountCount call")
 }
 
+func (s *proxyRepoStub) ListWithFiltersAndAccountCount(ctx context.Context, params pagination.PaginationParams, protocol, status, search string) ([]ProxyWithAccountCount, *pagination.PaginationResult, error) {
+	panic("unexpected ListWithFiltersAndAccountCount call")
+}
+
 func (s *proxyRepoStub) ExistsByHostPortAuth(ctx context.Context, host string, port int, username, password string) (bool, error) {
 	panic("unexpected ExistsByHostPortAuth call")
 }

backend/internal/service/auth_service.go

@@ -82,14 +82,18 @@ func (s *AuthService) RegisterWithVerification(ctx context.Context, email, passw
 
 	// 检查是否需要邮件验证
 	if s.settingService != nil && s.settingService.IsEmailVerifyEnabled(ctx) {
+		// 如果邮件验证已开启但邮件服务未配置，拒绝注册
+		// 这是一个配置错误，不应该允许绕过验证
+		if s.emailService == nil {
+			log.Println("[Auth] Email verification enabled but email service not configured, rejecting registration")
+			return "", nil, ErrServiceUnavailable
+		}
 		if verifyCode == "" {
 			return "", nil, ErrEmailVerifyRequired
 		}
 		// 验证邮箱验证码
-		if s.emailService != nil {
-			if err := s.emailService.VerifyCode(ctx, email, verifyCode); err != nil {
-				return "", nil, fmt.Errorf("verify code: %w", err)
-			}
+		if err := s.emailService.VerifyCode(ctx, email, verifyCode); err != nil {
+			return "", nil, fmt.Errorf("verify code: %w", err)
 		}
 	}
 
@@ -336,6 +340,11 @@ func (s *AuthService) ValidateToken(tokenString string) (*JWTClaims, error) {
 
 	if err != nil {
 		if errors.Is(err, jwt.ErrTokenExpired) {
+			// token 过期但仍返回 claims（用于 RefreshToken 等场景）
+			// jwt-go 在解析时即使遇到过期错误，token.Claims 仍会被填充
+			if claims, ok := token.Claims.(*JWTClaims); ok {
+				return claims, ErrTokenExpired
+			}
 			return nil, ErrTokenExpired
 		}
 		return nil, ErrInvalidToken

backend/internal/service/auth_service_register_test.go

@@ -113,13 +113,27 @@ func TestAuthService_Register_Disabled(t *testing.T) {
 	require.ErrorIs(t, err, ErrRegDisabled)
 }
 
-func TestAuthService_Register_EmailVerifyRequired(t *testing.T) {
+func TestAuthService_Register_EmailVerifyEnabledButServiceNotConfigured(t *testing.T) {
 	repo := &userRepoStub{}
+	// 邮件验证开启但 emailCache 为 nil（emailService 未配置）
 	service := newAuthService(repo, map[string]string{
 		SettingKeyRegistrationEnabled: "true",
 		SettingKeyEmailVerifyEnabled:  "true",
 	}, nil)
 
+	// 应返回服务不可用错误，而不是允许绕过验证
+	_, _, err := service.RegisterWithVerification(context.Background(), "user@test.com", "password", "any-code")
+	require.ErrorIs(t, err, ErrServiceUnavailable)
+}
+
+func TestAuthService_Register_EmailVerifyRequired(t *testing.T) {
+	repo := &userRepoStub{}
+	cache := &emailCacheStub{} // 配置 emailService
+	service := newAuthService(repo, map[string]string{
+		SettingKeyRegistrationEnabled: "true",
+		SettingKeyEmailVerifyEnabled:  "true",
+	}, cache)
+
 	_, _, err := service.RegisterWithVerification(context.Background(), "user@test.com", "password", "")
 	require.ErrorIs(t, err, ErrEmailVerifyRequired)
 }
@@ -180,3 +194,63 @@ func TestAuthService_Register_Success(t *testing.T) {
 	require.Len(t, repo.created, 1)
 	require.True(t, user.CheckPassword("password"))
 }
+
+func TestAuthService_ValidateToken_ExpiredReturnsClaimsWithError(t *testing.T) {
+	repo := &userRepoStub{}
+	service := newAuthService(repo, nil, nil)
+
+	// 创建用户并生成 token
+	user := &User{
+		ID:           1,
+		Email:        "test@test.com",
+		Role:         RoleUser,
+		Status:       StatusActive,
+		TokenVersion: 1,
+	}
+	token, err := service.GenerateToken(user)
+	require.NoError(t, err)
+
+	// 验证有效 token
+	claims, err := service.ValidateToken(token)
+	require.NoError(t, err)
+	require.NotNil(t, claims)
+	require.Equal(t, int64(1), claims.UserID)
+
+	// 模拟过期 token（通过创建一个过期很久的 token）
+	service.cfg.JWT.ExpireHour = -1 // 设置为负数使 token 立即过期
+	expiredToken, err := service.GenerateToken(user)
+	require.NoError(t, err)
+	service.cfg.JWT.ExpireHour = 1 // 恢复
+
+	// 验证过期 token 应返回 claims 和 ErrTokenExpired
+	claims, err = service.ValidateToken(expiredToken)
+	require.ErrorIs(t, err, ErrTokenExpired)
+	require.NotNil(t, claims, "claims should not be nil when token is expired")
+	require.Equal(t, int64(1), claims.UserID)
+	require.Equal(t, "test@test.com", claims.Email)
+}
+
+func TestAuthService_RefreshToken_ExpiredTokenNoPanic(t *testing.T) {
+	user := &User{
+		ID:           1,
+		Email:        "test@test.com",
+		Role:         RoleUser,
+		Status:       StatusActive,
+		TokenVersion: 1,
+	}
+	repo := &userRepoStub{user: user}
+	service := newAuthService(repo, nil, nil)
+
+	// 创建过期 token
+	service.cfg.JWT.ExpireHour = -1
+	expiredToken, err := service.GenerateToken(user)
+	require.NoError(t, err)
+	service.cfg.JWT.ExpireHour = 1
+
+	// RefreshToken 使用过期 token 不应 panic
+	require.NotPanics(t, func() {
+		newToken, err := service.RefreshToken(context.Background(), expiredToken)
+		require.NoError(t, err)
+		require.NotEmpty(t, newToken)
+	})
+}

backend/internal/service/claude_code_validator.go

@@ -0,0 +1,265 @@
+package service
+
+import (
+	"context"
+	"net/http"
+	"regexp"
+	"strings"
+
+	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
+)
+
+// ClaudeCodeValidator 验证请求是否来自 Claude Code 客户端
+// 完全学习自 claude-relay-service 项目的验证逻辑
+type ClaudeCodeValidator struct{}
+
+var (
+	// User-Agent 匹配: claude-cli/x.x.x (仅支持官方 CLI，大小写不敏感)
+	claudeCodeUAPattern = regexp.MustCompile(`(?i)^claude-cli/\d+\.\d+\.\d+`)
+
+	// metadata.user_id 格式: user_{64位hex}_account__session_{uuid}
+	userIDPattern = regexp.MustCompile(`^user_[a-fA-F0-9]{64}_account__session_[\w-]+$`)
+
+	// System prompt 相似度阈值（默认 0.5，和 claude-relay-service 一致）
+	systemPromptThreshold = 0.5
+)
+
+// Claude Code 官方 System Prompt 模板
+// 从 claude-relay-service/src/utils/contents.js 提取
+var claudeCodeSystemPrompts = []string{
+	// claudeOtherSystemPrompt1 - Primary
+	"You are Claude Code, Anthropic's official CLI for Claude.",
+
+	// claudeOtherSystemPrompt3 - Agent SDK
+	"You are a Claude agent, built on Anthropic's Claude Agent SDK.",
+
+	// claudeOtherSystemPrompt4 - Compact Agent SDK
+	"You are Claude Code, Anthropic's official CLI for Claude, running within the Claude Agent SDK.",
+
+	// exploreAgentSystemPrompt
+	"You are a file search specialist for Claude Code, Anthropic's official CLI for Claude.",
+
+	// claudeOtherSystemPromptCompact - Compact (用于对话摘要)
+	"You are a helpful AI assistant tasked with summarizing conversations.",
+
+	// claudeOtherSystemPrompt2 - Secondary (长提示词的关键部分)
+	"You are an interactive CLI tool that helps users",
+}
+
+// NewClaudeCodeValidator 创建验证器实例
+func NewClaudeCodeValidator() *ClaudeCodeValidator {
+	return &ClaudeCodeValidator{}
+}
+
+// Validate 验证请求是否来自 Claude Code CLI
+// 采用与 claude-relay-service 完全一致的验证策略：
+//
+//	Step 1: User-Agent 检查 (必需) - 必须是 claude-cli/x.x.x
+//	Step 2: 对于非 messages 路径，只要 UA 匹配就通过
+//	Step 3: 对于 messages 路径，进行严格验证：
+//	        - System prompt 相似度检查
+//	        - X-App header 检查
+//	        - anthropic-beta header 检查
+//	        - anthropic-version header 检查
+//	        - metadata.user_id 格式验证
+func (v *ClaudeCodeValidator) Validate(r *http.Request, body map[string]any) bool {
+	// Step 1: User-Agent 检查
+	ua := r.Header.Get("User-Agent")
+	if !claudeCodeUAPattern.MatchString(ua) {
+		return false
+	}
+
+	// Step 2: 非 messages 路径，只要 UA 匹配就通过
+	path := r.URL.Path
+	if !strings.Contains(path, "messages") {
+		return true
+	}
+
+	// Step 3: messages 路径，进行严格验证
+
+	// 3.1 检查 system prompt 相似度
+	if !v.hasClaudeCodeSystemPrompt(body) {
+		return false
+	}
+
+	// 3.2 检查必需的 headers（值不为空即可）
+	xApp := r.Header.Get("X-App")
+	if xApp == "" {
+		return false
+	}
+
+	anthropicBeta := r.Header.Get("anthropic-beta")
+	if anthropicBeta == "" {
+		return false
+	}
+
+	anthropicVersion := r.Header.Get("anthropic-version")
+	if anthropicVersion == "" {
+		return false
+	}
+
+	// 3.3 验证 metadata.user_id
+	if body == nil {
+		return false
+	}
+
+	metadata, ok := body["metadata"].(map[string]any)
+	if !ok {
+		return false
+	}
+
+	userID, ok := metadata["user_id"].(string)
+	if !ok || userID == "" {
+		return false
+	}
+
+	if !userIDPattern.MatchString(userID) {
+		return false
+	}
+
+	return true
+}
+
+// hasClaudeCodeSystemPrompt 检查请求是否包含 Claude Code 系统提示词
+// 使用字符串相似度匹配（Dice coefficient）
+func (v *ClaudeCodeValidator) hasClaudeCodeSystemPrompt(body map[string]any) bool {
+	if body == nil {
+		return false
+	}
+
+	// 检查 model 字段
+	if _, ok := body["model"].(string); !ok {
+		return false
+	}
+
+	// 获取 system 字段
+	systemEntries, ok := body["system"].([]any)
+	if !ok {
+		return false
+	}
+
+	// 检查每个 system entry
+	for _, entry := range systemEntries {
+		entryMap, ok := entry.(map[string]any)
+		if !ok {
+			continue
+		}
+
+		text, ok := entryMap["text"].(string)
+		if !ok || text == "" {
+			continue
+		}
+
+		// 计算与所有模板的最佳相似度
+		bestScore := v.bestSimilarityScore(text)
+		if bestScore >= systemPromptThreshold {
+			return true
+		}
+	}
+
+	return false
+}
+
+// bestSimilarityScore 计算文本与所有 Claude Code 模板的最佳相似度
+func (v *ClaudeCodeValidator) bestSimilarityScore(text string) float64 {
+	normalizedText := normalizePrompt(text)
+	bestScore := 0.0
+
+	for _, template := range claudeCodeSystemPrompts {
+		normalizedTemplate := normalizePrompt(template)
+		score := diceCoefficient(normalizedText, normalizedTemplate)
+		if score > bestScore {
+			bestScore = score
+		}
+	}
+
+	return bestScore
+}
+
+// normalizePrompt 标准化提示词文本（去除多余空白）
+func normalizePrompt(text string) string {
+	// 将所有空白字符替换为单个空格，并去除首尾空白
+	return strings.Join(strings.Fields(text), " ")
+}
+
+// diceCoefficient 计算两个字符串的 Dice 系数（Sørensen–Dice coefficient）
+// 这是 string-similarity 库使用的算法
+// 公式: 2 * |intersection| / (|bigrams(a)| + |bigrams(b)|)
+func diceCoefficient(a, b string) float64 {
+	if a == b {
+		return 1.0
+	}
+
+	if len(a) < 2 || len(b) < 2 {
+		return 0.0
+	}
+
+	// 生成 bigrams
+	bigramsA := getBigrams(a)
+	bigramsB := getBigrams(b)
+
+	if len(bigramsA) == 0 || len(bigramsB) == 0 {
+		return 0.0
+	}
+
+	// 计算交集大小
+	intersection := 0
+	for bigram, countA := range bigramsA {
+		if countB, exists := bigramsB[bigram]; exists {
+			if countA < countB {
+				intersection += countA
+			} else {
+				intersection += countB
+			}
+		}
+	}
+
+	// 计算总 bigram 数量
+	totalA := 0
+	for _, count := range bigramsA {
+		totalA += count
+	}
+	totalB := 0
+	for _, count := range bigramsB {
+		totalB += count
+	}
+
+	return float64(2*intersection) / float64(totalA+totalB)
+}
+
+// getBigrams 获取字符串的所有 bigrams（相邻字符对）
+func getBigrams(s string) map[string]int {
+	bigrams := make(map[string]int)
+	runes := []rune(strings.ToLower(s))
+
+	for i := 0; i < len(runes)-1; i++ {
+		bigram := string(runes[i : i+2])
+		bigrams[bigram]++
+	}
+
+	return bigrams
+}
+
+// ValidateUserAgent 仅验证 User-Agent（用于不需要解析请求体的场景）
+func (v *ClaudeCodeValidator) ValidateUserAgent(ua string) bool {
+	return claudeCodeUAPattern.MatchString(ua)
+}
+
+// IncludesClaudeCodeSystemPrompt 检查请求体是否包含 Claude Code 系统提示词
+// 只要存在匹配的系统提示词就返回 true（用于宽松检测）
+func (v *ClaudeCodeValidator) IncludesClaudeCodeSystemPrompt(body map[string]any) bool {
+	return v.hasClaudeCodeSystemPrompt(body)
+}
+
+// IsClaudeCodeClient 从 context 中获取 Claude Code 客户端标识
+func IsClaudeCodeClient(ctx context.Context) bool {
+	if v, ok := ctx.Value(ctxkey.IsClaudeCodeClient).(bool); ok {
+		return v
+	}
+	return false
+}
+
+// SetClaudeCodeClient 将 Claude Code 客户端标识设置到 context 中
+func SetClaudeCodeClient(ctx context.Context, isClaudeCode bool) context.Context {
+	return context.WithValue(ctx, ctxkey.IsClaudeCodeClient, isClaudeCode)
+}

backend/internal/service/gateway_multiplatform_test.go

@@ -166,14 +166,14 @@ type mockGatewayCacheForPlatform struct {
 	sessionBindings map[string]int64
 }
 
-func (m *mockGatewayCacheForPlatform) GetSessionAccountID(ctx context.Context, sessionHash string) (int64, error) {
+func (m *mockGatewayCacheForPlatform) GetSessionAccountID(ctx context.Context, groupID int64, sessionHash string) (int64, error) {
 	if id, ok := m.sessionBindings[sessionHash]; ok {
 		return id, nil
 	}
 	return 0, errors.New("not found")
 }
 
-func (m *mockGatewayCacheForPlatform) SetSessionAccountID(ctx context.Context, sessionHash string, accountID int64, ttl time.Duration) error {
+func (m *mockGatewayCacheForPlatform) SetSessionAccountID(ctx context.Context, groupID int64, sessionHash string, accountID int64, ttl time.Duration) error {
 	if m.sessionBindings == nil {
 		m.sessionBindings = make(map[string]int64)
 	}
@@ -181,7 +181,7 @@ func (m *mockGatewayCacheForPlatform) SetSessionAccountID(ctx context.Context, s
 	return nil
 }
 
-func (m *mockGatewayCacheForPlatform) RefreshSessionTTL(ctx context.Context, sessionHash string, ttl time.Duration) error {
+func (m *mockGatewayCacheForPlatform) RefreshSessionTTL(ctx context.Context, groupID int64, sessionHash string, ttl time.Duration) error {
 	return nil
 }
 

backend/internal/service/gateway_service.go

@@ -56,6 +56,9 @@ var (
 	}
 )
 
+// ErrClaudeCodeOnly 表示分组仅允许 Claude Code 客户端访问
+var ErrClaudeCodeOnly = errors.New("this group only allows Claude Code clients")
+
 // allowedHeaders 白名单headers（参考CRS项目）
 var allowedHeaders = map[string]bool{
 	"accept":                                    true,
@@ -80,9 +83,17 @@ var allowedHeaders = map[string]bool{
 
 // GatewayCache defines cache operations for gateway service
 type GatewayCache interface {
-	GetSessionAccountID(ctx context.Context, sessionHash string) (int64, error)
-	SetSessionAccountID(ctx context.Context, sessionHash string, accountID int64, ttl time.Duration) error
-	RefreshSessionTTL(ctx context.Context, sessionHash string, ttl time.Duration) error
+	GetSessionAccountID(ctx context.Context, groupID int64, sessionHash string) (int64, error)
+	SetSessionAccountID(ctx context.Context, groupID int64, sessionHash string, accountID int64, ttl time.Duration) error
+	RefreshSessionTTL(ctx context.Context, groupID int64, sessionHash string, ttl time.Duration) error
+}
+
+// derefGroupID safely dereferences *int64 to int64, returning 0 if nil
+func derefGroupID(groupID *int64) int64 {
+	if groupID == nil {
+		return 0
+	}
+	return *groupID
 }
 
 type AccountWaitPlan struct {
@@ -109,12 +120,13 @@ type ClaudeUsage struct {
 
 // ForwardResult 转发结果
 type ForwardResult struct {
-	RequestID    string
-	Usage        ClaudeUsage
-	Model        string
-	Stream       bool
-	Duration     time.Duration
-	FirstTokenMs *int // 首字时间（流式请求）
+	RequestID        string
+	Usage            ClaudeUsage
+	Model            string
+	Stream           bool
+	Duration         time.Duration
+	FirstTokenMs     *int // 首字时间（流式请求）
+	ClientDisconnect bool // 客户端是否在流式传输过程中断开
 
 	// 图片生成计费字段（仅 gemini-3-pro-image 使用）
 	ImageCount int    // 生成的图片数量
@@ -224,11 +236,11 @@ func (s *GatewayService) GenerateSessionHash(parsed *ParsedRequest) string {
 }
 
 // BindStickySession sets session -> account binding with standard TTL.
-func (s *GatewayService) BindStickySession(ctx context.Context, sessionHash string, accountID int64) error {
+func (s *GatewayService) BindStickySession(ctx context.Context, groupID *int64, sessionHash string, accountID int64) error {
 	if sessionHash == "" || accountID <= 0 || s.cache == nil {
 		return nil
 	}
-	return s.cache.SetSessionAccountID(ctx, sessionHash, accountID, stickySessionTTL)
+	return s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), sessionHash, accountID, stickySessionTTL)
 }
 
 func (s *GatewayService) extractCacheableContent(parsed *ParsedRequest) string {
@@ -355,6 +367,21 @@ func (s *GatewayService) SelectAccountForModelWithExclusions(ctx context.Context
 			return nil, fmt.Errorf("get group failed: %w", err)
 		}
 		platform = group.Platform
+
+		// 检查 Claude Code 客户端限制
+		if group.ClaudeCodeOnly {
+			isClaudeCode := IsClaudeCodeClient(ctx)
+			if !isClaudeCode {
+				// 非 Claude Code 客户端，检查是否有降级分组
+				if group.FallbackGroupID != nil {
+					// 使用降级分组重新调度
+					fallbackGroupID := *group.FallbackGroupID
+					return s.SelectAccountForModelWithExclusions(ctx, &fallbackGroupID, sessionHash, requestedModel, excludedIDs)
+				}
+				// 无降级分组，拒绝访问
+				return nil, ErrClaudeCodeOnly
+			}
+		}
 	} else {
 		// 无分组时只使用原生 anthropic 平台
 		platform = PlatformAnthropic
@@ -376,10 +403,17 @@ func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, gro
 	cfg := s.schedulingConfig()
 	var stickyAccountID int64
 	if sessionHash != "" && s.cache != nil {
-		if accountID, err := s.cache.GetSessionAccountID(ctx, sessionHash); err == nil {
+		if accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), sessionHash); err == nil {
 			stickyAccountID = accountID
 		}
 	}
+
+	// 检查 Claude Code 客户端限制（可能会替换 groupID 为降级分组）
+	groupID, err := s.checkClaudeCodeRestriction(ctx, groupID)
+	if err != nil {
+		return nil, err
+	}
+
 	if s.concurrencyService == nil || !cfg.LoadBatchEnabled {
 		account, err := s.SelectAccountForModelWithExclusions(ctx, groupID, sessionHash, requestedModel, excludedIDs)
 		if err != nil {
@@ -442,7 +476,7 @@ func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, gro
 
 	// ============ Layer 1: 粘性会话优先 ============
 	if sessionHash != "" && s.cache != nil {
-		accountID, err := s.cache.GetSessionAccountID(ctx, sessionHash)
+		accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), sessionHash)
 		if err == nil && accountID > 0 && !isExcluded(accountID) {
 			account, err := s.accountRepo.GetByID(ctx, accountID)
 			if err == nil && s.isAccountInGroup(account, groupID) &&
@@ -451,7 +485,7 @@ func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, gro
 				(requestedModel == "" || s.isModelSupportedByAccount(account, requestedModel)) {
 				result, err := s.tryAcquireAccountSlot(ctx, accountID, account.Concurrency)
 				if err == nil && result.Acquired {
-					_ = s.cache.RefreshSessionTTL(ctx, sessionHash, stickySessionTTL)
+					_ = s.cache.RefreshSessionTTL(ctx, derefGroupID(groupID), sessionHash, stickySessionTTL)
 					return &AccountSelectionResult{
 						Account:     account,
 						Acquired:    true,
@@ -505,7 +539,7 @@ func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, gro
 
 	loadMap, err := s.concurrencyService.GetAccountsLoadBatch(ctx, accountLoads)
 	if err != nil {
-		if result, ok := s.tryAcquireByLegacyOrder(ctx, candidates, sessionHash, preferOAuth); ok {
+		if result, ok := s.tryAcquireByLegacyOrder(ctx, candidates, groupID, sessionHash, preferOAuth); ok {
 			return result, nil
 		}
 	} else {
@@ -555,7 +589,7 @@ func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, gro
 				result, err := s.tryAcquireAccountSlot(ctx, item.account.ID, item.account.Concurrency)
 				if err == nil && result.Acquired {
 					if sessionHash != "" && s.cache != nil {
-						_ = s.cache.SetSessionAccountID(ctx, sessionHash, item.account.ID, stickySessionTTL)
+						_ = s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), sessionHash, item.account.ID, stickySessionTTL)
 					}
 					return &AccountSelectionResult{
 						Account:     item.account,
@@ -583,7 +617,7 @@ func (s *GatewayService) SelectAccountWithLoadAwareness(ctx context.Context, gro
 	return nil, errors.New("no available accounts")
 }
 
-func (s *GatewayService) tryAcquireByLegacyOrder(ctx context.Context, candidates []*Account, sessionHash string, preferOAuth bool) (*AccountSelectionResult, bool) {
+func (s *GatewayService) tryAcquireByLegacyOrder(ctx context.Context, candidates []*Account, groupID *int64, sessionHash string, preferOAuth bool) (*AccountSelectionResult, bool) {
 	ordered := append([]*Account(nil), candidates...)
 	sortAccountsByPriorityAndLastUsed(ordered, preferOAuth)
 
@@ -591,7 +625,7 @@ func (s *GatewayService) tryAcquireByLegacyOrder(ctx context.Context, candidates
 		result, err := s.tryAcquireAccountSlot(ctx, acc.ID, acc.Concurrency)
 		if err == nil && result.Acquired {
 			if sessionHash != "" && s.cache != nil {
-				_ = s.cache.SetSessionAccountID(ctx, sessionHash, acc.ID, stickySessionTTL)
+				_ = s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), sessionHash, acc.ID, stickySessionTTL)
 			}
 			return &AccountSelectionResult{
 				Account:     acc,
@@ -618,6 +652,42 @@ func (s *GatewayService) schedulingConfig() config.GatewaySchedulingConfig {
 	}
 }
 
+// checkClaudeCodeRestriction 检查分组的 Claude Code 客户端限制
+// 如果分组启用了 claude_code_only 且请求不是来自 Claude Code 客户端：
+//   - 有降级分组：返回降级分组的 ID
+//   - 无降级分组：返回 ErrClaudeCodeOnly 错误
+func (s *GatewayService) checkClaudeCodeRestriction(ctx context.Context, groupID *int64) (*int64, error) {
+	if groupID == nil {
+		return groupID, nil
+	}
+
+	// 强制平台模式不检查 Claude Code 限制
+	if _, hasForcePlatform := ctx.Value(ctxkey.ForcePlatform).(string); hasForcePlatform {
+		return groupID, nil
+	}
+
+	group, err := s.groupRepo.GetByID(ctx, *groupID)
+	if err != nil {
+		return nil, fmt.Errorf("get group failed: %w", err)
+	}
+
+	if !group.ClaudeCodeOnly {
+		return groupID, nil
+	}
+
+	// 分组启用了 Claude Code 限制
+	if IsClaudeCodeClient(ctx) {
+		return groupID, nil
+	}
+
+	// 非 Claude Code 客户端，检查降级分组
+	if group.FallbackGroupID != nil {
+		return group.FallbackGroupID, nil
+	}
+
+	return nil, ErrClaudeCodeOnly
+}
+
 func (s *GatewayService) resolvePlatform(ctx context.Context, groupID *int64) (string, bool, error) {
 	forcePlatform, hasForcePlatform := ctx.Value(ctxkey.ForcePlatform).(string)
 	if hasForcePlatform && forcePlatform != "" {
@@ -737,13 +807,13 @@ func (s *GatewayService) selectAccountForModelWithPlatform(ctx context.Context,
 	preferOAuth := platform == PlatformGemini
 	// 1. 查询粘性会话
 	if sessionHash != "" && s.cache != nil {
-		accountID, err := s.cache.GetSessionAccountID(ctx, sessionHash)
+		accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), sessionHash)
 		if err == nil && accountID > 0 {
 			if _, excluded := excludedIDs[accountID]; !excluded {
 				account, err := s.accountRepo.GetByID(ctx, accountID)
 				// 检查账号分组归属和平台匹配（确保粘性会话不会跨分组或跨平台）
 				if err == nil && s.isAccountInGroup(account, groupID) && account.Platform == platform && account.IsSchedulable() && (requestedModel == "" || s.isModelSupportedByAccount(account, requestedModel)) {
-					if err := s.cache.RefreshSessionTTL(ctx, sessionHash, stickySessionTTL); err != nil {
+					if err := s.cache.RefreshSessionTTL(ctx, derefGroupID(groupID), sessionHash, stickySessionTTL); err != nil {
 						log.Printf("refresh session ttl failed: session=%s err=%v", sessionHash, err)
 					}
 					return account, nil
@@ -810,7 +880,7 @@ func (s *GatewayService) selectAccountForModelWithPlatform(ctx context.Context,
 
 	// 4. 建立粘性绑定
 	if sessionHash != "" && s.cache != nil {
-		if err := s.cache.SetSessionAccountID(ctx, sessionHash, selected.ID, stickySessionTTL); err != nil {
+		if err := s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), sessionHash, selected.ID, stickySessionTTL); err != nil {
 			log.Printf("set session account failed: session=%s account_id=%d err=%v", sessionHash, selected.ID, err)
 		}
 	}
@@ -826,14 +896,14 @@ func (s *GatewayService) selectAccountWithMixedScheduling(ctx context.Context, g
 
 	// 1. 查询粘性会话
 	if sessionHash != "" && s.cache != nil {
-		accountID, err := s.cache.GetSessionAccountID(ctx, sessionHash)
+		accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), sessionHash)
 		if err == nil && accountID > 0 {
 			if _, excluded := excludedIDs[accountID]; !excluded {
 				account, err := s.accountRepo.GetByID(ctx, accountID)
 				// 检查账号分组归属和有效性：原生平台直接匹配，antigravity 需要启用混合调度
 				if err == nil && s.isAccountInGroup(account, groupID) && account.IsSchedulable() && (requestedModel == "" || s.isModelSupportedByAccount(account, requestedModel)) {
 					if account.Platform == nativePlatform || (account.Platform == PlatformAntigravity && account.IsMixedSchedulingEnabled()) {
-						if err := s.cache.RefreshSessionTTL(ctx, sessionHash, stickySessionTTL); err != nil {
+						if err := s.cache.RefreshSessionTTL(ctx, derefGroupID(groupID), sessionHash, stickySessionTTL); err != nil {
 							log.Printf("refresh session ttl failed: session=%s err=%v", sessionHash, err)
 						}
 						return account, nil
@@ -902,7 +972,7 @@ func (s *GatewayService) selectAccountWithMixedScheduling(ctx context.Context, g
 
 	// 4. 建立粘性绑定
 	if sessionHash != "" && s.cache != nil {
-		if err := s.cache.SetSessionAccountID(ctx, sessionHash, selected.ID, stickySessionTTL); err != nil {
+		if err := s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), sessionHash, selected.ID, stickySessionTTL); err != nil {
 			log.Printf("set session account failed: session=%s account_id=%d err=%v", sessionHash, selected.ID, err)
 		}
 	}
@@ -1465,6 +1535,7 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 	// 处理正常响应
 	var usage *ClaudeUsage
 	var firstTokenMs *int
+	var clientDisconnect bool
 	if reqStream {
 		streamResult, err := s.handleStreamingResponse(ctx, resp, c, account, startTime, originalModel, reqModel)
 		if err != nil {
@@ -1477,6 +1548,7 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 		}
 		usage = streamResult.usage
 		firstTokenMs = streamResult.firstTokenMs
+		clientDisconnect = streamResult.clientDisconnect
 	} else {
 		usage, err = s.handleNonStreamingResponse(ctx, resp, c, account, originalModel, reqModel)
 		if err != nil {
@@ -1485,12 +1557,13 @@ func (s *GatewayService) Forward(ctx context.Context, c *gin.Context, account *A
 	}
 
 	return &ForwardResult{
-		RequestID:    resp.Header.Get("x-request-id"),
-		Usage:        *usage,
-		Model:        originalModel, // 使用原始模型用于计费和日志
-		Stream:       reqStream,
-		Duration:     time.Since(startTime),
-		FirstTokenMs: firstTokenMs,
+		RequestID:        resp.Header.Get("x-request-id"),
+		Usage:            *usage,
+		Model:            originalModel, // 使用原始模型用于计费和日志
+		Stream:           reqStream,
+		Duration:         time.Since(startTime),
+		FirstTokenMs:     firstTokenMs,
+		ClientDisconnect: clientDisconnect,
 	}, nil
 }
 
@@ -1845,8 +1918,9 @@ func (s *GatewayService) handleRetryExhaustedError(ctx context.Context, resp *ht
 
 // streamingResult 流式响应结果
 type streamingResult struct {
-	usage        *ClaudeUsage
-	firstTokenMs *int
+	usage            *ClaudeUsage
+	firstTokenMs     *int
+	clientDisconnect bool // 客户端是否在流式传输过程中断开
 }
 
 func (s *GatewayService) handleStreamingResponse(ctx context.Context, resp *http.Response, c *gin.Context, account *Account, startTime time.Time, originalModel, mappedModel string) (*streamingResult, error) {
@@ -1942,14 +2016,27 @@ func (s *GatewayService) handleStreamingResponse(ctx context.Context, resp *http
 	}
 
 	needModelReplace := originalModel != mappedModel
+	clientDisconnected := false // 客户端断开标志，断开后继续读取上游以获取完整usage
 
 	for {
 		select {
 		case ev, ok := <-events:
 			if !ok {
-				return &streamingResult{usage: usage, firstTokenMs: firstTokenMs}, nil
+				// 上游完成，返回结果
+				return &streamingResult{usage: usage, firstTokenMs: firstTokenMs, clientDisconnect: clientDisconnected}, nil
 			}
 			if ev.err != nil {
+				// 检测 context 取消（客户端断开会导致 context 取消，进而影响上游读取）
+				if errors.Is(ev.err, context.Canceled) || errors.Is(ev.err, context.DeadlineExceeded) {
+					log.Printf("Context canceled during streaming, returning collected usage")
+					return &streamingResult{usage: usage, firstTokenMs: firstTokenMs, clientDisconnect: true}, nil
+				}
+				// 客户端已通过写入失败检测到断开，上游也出错了，返回已收集的 usage
+				if clientDisconnected {
+					log.Printf("Upstream read error after client disconnect: %v, returning collected usage", ev.err)
+					return &streamingResult{usage: usage, firstTokenMs: firstTokenMs, clientDisconnect: true}, nil
+				}
+				// 客户端未断开，正常的错误处理
 				if errors.Is(ev.err, bufio.ErrTooLong) {
 					log.Printf("SSE line too long: account=%d max_size=%d error=%v", account.ID, maxLineSize, ev.err)
 					sendErrorEvent("response_too_large")
@@ -1960,38 +2047,40 @@ func (s *GatewayService) handleStreamingResponse(ctx context.Context, resp *http
 			}
 			line := ev.line
 			if line == "event: error" {
+				// 上游返回错误事件，如果客户端已断开仍返回已收集的 usage
+				if clientDisconnected {
+					return &streamingResult{usage: usage, firstTokenMs: firstTokenMs, clientDisconnect: true}, nil
+				}
 				return nil, errors.New("have error in stream")
 			}
 
 			// Extract data from SSE line (supports both "data: " and "data:" formats)
+			var data string
 			if sseDataRe.MatchString(line) {
-				data := sseDataRe.ReplaceAllString(line, "")
-
+				data = sseDataRe.ReplaceAllString(line, "")
 				// 如果有模型映射，替换响应中的model字段
 				if needModelReplace {
 					line = s.replaceModelInSSELine(line, mappedModel, originalModel)
 				}
+			}
 
-				// 转发行
+			// 写入客户端（统一处理 data 行和非 data 行）
+			if !clientDisconnected {
 				if _, err := fmt.Fprintf(w, "%s\n", line); err != nil {
-					sendErrorEvent("write_failed")
-					return &streamingResult{usage: usage, firstTokenMs: firstTokenMs}, err
+					clientDisconnected = true
+					log.Printf("Client disconnected during streaming, continuing to drain upstream for billing")
+				} else {
+					flusher.Flush()
 				}
-				flusher.Flush()
+			}
 
-				// 记录首字时间：第一个有效的 content_block_delta 或 message_start
-				if firstTokenMs == nil && data != "" && data != "[DONE]" {
+			// 无论客户端是否断开，都解析 usage（仅对 data 行）
+			if data != "" {
+				if firstTokenMs == nil && data != "[DONE]" {
 					ms := int(time.Since(startTime).Milliseconds())
 					firstTokenMs = &ms
 				}
 				s.parseSSEUsage(data, usage)
-			} else {
-				// 非 data 行直接转发
-				if _, err := fmt.Fprintf(w, "%s\n", line); err != nil {
-					sendErrorEvent("write_failed")
-					return &streamingResult{usage: usage, firstTokenMs: firstTokenMs}, err
-				}
-				flusher.Flush()
 			}
 
 		case <-intervalCh:
@@ -1999,6 +2088,11 @@ func (s *GatewayService) handleStreamingResponse(ctx context.Context, resp *http
 			if time.Since(lastRead) < streamInterval {
 				continue
 			}
+			if clientDisconnected {
+				// 客户端已断开，上游也超时了，返回已收集的 usage
+				log.Printf("Upstream timeout after client disconnect, returning collected usage")
+				return &streamingResult{usage: usage, firstTokenMs: firstTokenMs, clientDisconnect: true}, nil
+			}
 			log.Printf("Stream data interval timeout: account=%d model=%s interval=%s", account.ID, originalModel, streamInterval)
 			sendErrorEvent("stream_timeout")
 			return &streamingResult{usage: usage, firstTokenMs: firstTokenMs}, fmt.Errorf("stream data interval timeout")

backend/internal/service/gemini_messages_compat_service.go

@@ -109,7 +109,7 @@ func (s *GeminiMessagesCompatService) SelectAccountForModelWithExclusions(ctx co
 	cacheKey := "gemini:" + sessionHash
 
 	if sessionHash != "" {
-		accountID, err := s.cache.GetSessionAccountID(ctx, cacheKey)
+		accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), cacheKey)
 		if err == nil && accountID > 0 {
 			if _, excluded := excludedIDs[accountID]; !excluded {
 				account, err := s.accountRepo.GetByID(ctx, accountID)
@@ -133,7 +133,7 @@ func (s *GeminiMessagesCompatService) SelectAccountForModelWithExclusions(ctx co
 							}
 						}
 						if usable {
-							_ = s.cache.RefreshSessionTTL(ctx, cacheKey, geminiStickySessionTTL)
+							_ = s.cache.RefreshSessionTTL(ctx, derefGroupID(groupID), cacheKey, geminiStickySessionTTL)
 							return account, nil
 						}
 					}
@@ -217,7 +217,7 @@ func (s *GeminiMessagesCompatService) SelectAccountForModelWithExclusions(ctx co
 	}
 
 	if sessionHash != "" {
-		_ = s.cache.SetSessionAccountID(ctx, cacheKey, selected.ID, geminiStickySessionTTL)
+		_ = s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), cacheKey, selected.ID, geminiStickySessionTTL)
 	}
 
 	return selected, nil

backend/internal/service/gemini_multiplatform_test.go

@@ -190,14 +190,14 @@ type mockGatewayCacheForGemini struct {
 	sessionBindings map[string]int64
 }
 
-func (m *mockGatewayCacheForGemini) GetSessionAccountID(ctx context.Context, sessionHash string) (int64, error) {
+func (m *mockGatewayCacheForGemini) GetSessionAccountID(ctx context.Context, groupID int64, sessionHash string) (int64, error) {
 	if id, ok := m.sessionBindings[sessionHash]; ok {
 		return id, nil
 	}
 	return 0, errors.New("not found")
 }
 
-func (m *mockGatewayCacheForGemini) SetSessionAccountID(ctx context.Context, sessionHash string, accountID int64, ttl time.Duration) error {
+func (m *mockGatewayCacheForGemini) SetSessionAccountID(ctx context.Context, groupID int64, sessionHash string, accountID int64, ttl time.Duration) error {
 	if m.sessionBindings == nil {
 		m.sessionBindings = make(map[string]int64)
 	}
@@ -205,7 +205,7 @@ func (m *mockGatewayCacheForGemini) SetSessionAccountID(ctx context.Context, ses
 	return nil
 }
 
-func (m *mockGatewayCacheForGemini) RefreshSessionTTL(ctx context.Context, sessionHash string, ttl time.Duration) error {
+func (m *mockGatewayCacheForGemini) RefreshSessionTTL(ctx context.Context, groupID int64, sessionHash string, ttl time.Duration) error {
 	return nil
 }
 

backend/internal/service/gemini_oauth_service.go

@@ -120,15 +120,16 @@ func (s *GeminiOAuthService) GenerateAuthURL(ctx context.Context, proxyID *int64
 	}
 
 	// OAuth client selection:
-	// - code_assist: always use built-in Gemini CLI OAuth client (public), regardless of configured client_id/secret.
-	// - google_one: uses configured OAuth client when provided; otherwise falls back to built-in client.
-	// - ai_studio: requires a user-provided OAuth client.
+	// - code_assist: always use built-in Gemini CLI OAuth client (public)
+	// - google_one: always use built-in Gemini CLI OAuth client (public)
+	// - ai_studio: requires a user-provided OAuth client
 	oauthCfg := geminicli.OAuthConfig{
 		ClientID:     s.cfg.Gemini.OAuth.ClientID,
 		ClientSecret: s.cfg.Gemini.OAuth.ClientSecret,
 		Scopes:       s.cfg.Gemini.OAuth.Scopes,
 	}
-	if oauthType == "code_assist" {
+	if oauthType == "code_assist" || oauthType == "google_one" {
+		// Force use of built-in Gemini CLI OAuth client
 		oauthCfg.ClientID = ""
 		oauthCfg.ClientSecret = ""
 	}
@@ -576,6 +577,20 @@ func (s *GeminiOAuthService) ExchangeCode(ctx context.Context, input *GeminiExch
 
 	case "google_one":
 		log.Printf("[GeminiOAuth] Processing google_one OAuth type")
+
+		// Google One accounts use cloudaicompanion API, which requires a project_id.
+		// For personal accounts, Google auto-assigns a project_id via the LoadCodeAssist API.
+		if projectID == "" {
+			log.Printf("[GeminiOAuth] No project_id provided, attempting to fetch from LoadCodeAssist API...")
+			var err error
+			projectID, _, err = s.fetchProjectID(ctx, tokenResp.AccessToken, proxyURL)
+			if err != nil {
+				log.Printf("[GeminiOAuth] ERROR: Failed to fetch project_id: %v", err)
+				return nil, fmt.Errorf("google One accounts require a project_id, failed to auto-detect: %w", err)
+			}
+			log.Printf("[GeminiOAuth] Successfully fetched project_id: %s", projectID)
+		}
+
 		log.Printf("[GeminiOAuth] Attempting to fetch Google One tier from Drive API...")
 		// Attempt to fetch Drive storage tier
 		var storageInfo *geminicli.DriveStorageInfo

backend/internal/service/gemini_oauth_service_test.go

@@ -40,7 +40,7 @@ func TestGeminiOAuthService_GenerateAuthURL_RedirectURIStrategy(t *testing.T) {
 			wantProjectID: "",
 		},
 		{
-			name: "google_one uses custom client when configured and redirects to localhost",
+			name: "google_one always forces built-in client even when custom client configured",
 			cfg: &config.Config{
 				Gemini: config.GeminiConfig{
 					OAuth: config.GeminiOAuthConfig{
@@ -50,9 +50,9 @@ func TestGeminiOAuthService_GenerateAuthURL_RedirectURIStrategy(t *testing.T) {
 				},
 			},
 			oauthType:     "google_one",
-			wantClientID:  "custom-client-id",
-			wantRedirect:  geminicli.AIStudioOAuthRedirectURI,
-			wantScope:     geminicli.DefaultGoogleOneScopes,
+			wantClientID:  geminicli.GeminiCLIOAuthClientID,
+			wantRedirect:  geminicli.GeminiCLIRedirectURI,
+			wantScope:     geminicli.DefaultCodeAssistScopes,
 			wantProjectID: "",
 		},
 		{

backend/internal/service/group.go

@@ -22,6 +22,10 @@ type Group struct {
 	ImagePrice2K *float64
 	ImagePrice4K *float64
 
+	// Claude Code 客户端限制
+	ClaudeCodeOnly  bool
+	FallbackGroupID *int64
+
 	CreatedAt time.Time
 	UpdatedAt time.Time
 

backend/internal/service/openai_gateway_service.go

@@ -134,11 +134,11 @@ func (s *OpenAIGatewayService) GenerateSessionHash(c *gin.Context) string {
 }
 
 // BindStickySession sets session -> account binding with standard TTL.
-func (s *OpenAIGatewayService) BindStickySession(ctx context.Context, sessionHash string, accountID int64) error {
+func (s *OpenAIGatewayService) BindStickySession(ctx context.Context, groupID *int64, sessionHash string, accountID int64) error {
 	if sessionHash == "" || accountID <= 0 {
 		return nil
 	}
-	return s.cache.SetSessionAccountID(ctx, "openai:"+sessionHash, accountID, openaiStickySessionTTL)
+	return s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), "openai:"+sessionHash, accountID, openaiStickySessionTTL)
 }
 
 // SelectAccount selects an OpenAI account with sticky session support
@@ -155,13 +155,13 @@ func (s *OpenAIGatewayService) SelectAccountForModel(ctx context.Context, groupI
 func (s *OpenAIGatewayService) SelectAccountForModelWithExclusions(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}) (*Account, error) {
 	// 1. Check sticky session
 	if sessionHash != "" {
-		accountID, err := s.cache.GetSessionAccountID(ctx, "openai:"+sessionHash)
+		accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), "openai:"+sessionHash)
 		if err == nil && accountID > 0 {
 			if _, excluded := excludedIDs[accountID]; !excluded {
 				account, err := s.accountRepo.GetByID(ctx, accountID)
 				if err == nil && account.IsSchedulable() && account.IsOpenAI() && (requestedModel == "" || account.IsModelSupported(requestedModel)) {
 					// Refresh sticky session TTL
-					_ = s.cache.RefreshSessionTTL(ctx, "openai:"+sessionHash, openaiStickySessionTTL)
+					_ = s.cache.RefreshSessionTTL(ctx, derefGroupID(groupID), "openai:"+sessionHash, openaiStickySessionTTL)
 					return account, nil
 				}
 			}
@@ -227,7 +227,7 @@ func (s *OpenAIGatewayService) SelectAccountForModelWithExclusions(ctx context.C
 
 	// 4. Set sticky session
 	if sessionHash != "" {
-		_ = s.cache.SetSessionAccountID(ctx, "openai:"+sessionHash, selected.ID, openaiStickySessionTTL)
+		_ = s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), "openai:"+sessionHash, selected.ID, openaiStickySessionTTL)
 	}
 
 	return selected, nil
@@ -238,7 +238,7 @@ func (s *OpenAIGatewayService) SelectAccountWithLoadAwareness(ctx context.Contex
 	cfg := s.schedulingConfig()
 	var stickyAccountID int64
 	if sessionHash != "" && s.cache != nil {
-		if accountID, err := s.cache.GetSessionAccountID(ctx, "openai:"+sessionHash); err == nil {
+		if accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), "openai:"+sessionHash); err == nil {
 			stickyAccountID = accountID
 		}
 	}
@@ -298,14 +298,14 @@ func (s *OpenAIGatewayService) SelectAccountWithLoadAwareness(ctx context.Contex
 
 	// ============ Layer 1: Sticky session ============
 	if sessionHash != "" {
-		accountID, err := s.cache.GetSessionAccountID(ctx, "openai:"+sessionHash)
+		accountID, err := s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), "openai:"+sessionHash)
 		if err == nil && accountID > 0 && !isExcluded(accountID) {
 			account, err := s.accountRepo.GetByID(ctx, accountID)
 			if err == nil && account.IsSchedulable() && account.IsOpenAI() &&
 				(requestedModel == "" || account.IsModelSupported(requestedModel)) {
 				result, err := s.tryAcquireAccountSlot(ctx, accountID, account.Concurrency)
 				if err == nil && result.Acquired {
-					_ = s.cache.RefreshSessionTTL(ctx, "openai:"+sessionHash, openaiStickySessionTTL)
+					_ = s.cache.RefreshSessionTTL(ctx, derefGroupID(groupID), "openai:"+sessionHash, openaiStickySessionTTL)
 					return &AccountSelectionResult{
 						Account:     account,
 						Acquired:    true,
@@ -362,7 +362,7 @@ func (s *OpenAIGatewayService) SelectAccountWithLoadAwareness(ctx context.Contex
 			result, err := s.tryAcquireAccountSlot(ctx, acc.ID, acc.Concurrency)
 			if err == nil && result.Acquired {
 				if sessionHash != "" {
-					_ = s.cache.SetSessionAccountID(ctx, "openai:"+sessionHash, acc.ID, openaiStickySessionTTL)
+					_ = s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), "openai:"+sessionHash, acc.ID, openaiStickySessionTTL)
 				}
 				return &AccountSelectionResult{
 					Account:     acc,
@@ -415,7 +415,7 @@ func (s *OpenAIGatewayService) SelectAccountWithLoadAwareness(ctx context.Contex
 				result, err := s.tryAcquireAccountSlot(ctx, item.account.ID, item.account.Concurrency)
 				if err == nil && result.Acquired {
 					if sessionHash != "" {
-						_ = s.cache.SetSessionAccountID(ctx, "openai:"+sessionHash, item.account.ID, openaiStickySessionTTL)
+						_ = s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), "openai:"+sessionHash, item.account.ID, openaiStickySessionTTL)
 					}
 					return &AccountSelectionResult{
 						Account:     item.account,
@@ -540,10 +540,19 @@ func (s *OpenAIGatewayService) Forward(ctx context.Context, c *gin.Context, acco
 		bodyModified = true
 	}
 
-	// For OAuth accounts using ChatGPT internal API, add store: false
+	// For OAuth accounts using ChatGPT internal API:
+	// 1. Add store: false
+	// 2. Normalize input format for Codex API compatibility
 	if account.Type == AccountTypeOAuth {
 		reqBody["store"] = false
 		bodyModified = true
+
+		// Normalize input format: convert AI SDK multi-part content format to simplified format
+		// AI SDK sends: {"content": [{"type": "input_text", "text": "..."}]}
+		// Codex API expects: {"content": "..."}
+		if normalizeInputForCodexAPI(reqBody) {
+			bodyModified = true
+		}
 	}
 
 	// Re-serialize body only if modified
@@ -1085,6 +1094,101 @@ func (s *OpenAIGatewayService) replaceModelInResponseBody(body []byte, fromModel
 	return newBody
 }
 
+// normalizeInputForCodexAPI converts AI SDK multi-part content format to simplified format
+// that the ChatGPT internal Codex API expects.
+//
+// AI SDK sends content as an array of typed objects:
+//
+//	{"content": [{"type": "input_text", "text": "hello"}]}
+//
+// ChatGPT Codex API expects content as a simple string:
+//
+//	{"content": "hello"}
+//
+// This function modifies reqBody in-place and returns true if any modification was made.
+func normalizeInputForCodexAPI(reqBody map[string]any) bool {
+	input, ok := reqBody["input"]
+	if !ok {
+		return false
+	}
+
+	// Handle case where input is a simple string (already compatible)
+	if _, isString := input.(string); isString {
+		return false
+	}
+
+	// Handle case where input is an array of messages
+	inputArray, ok := input.([]any)
+	if !ok {
+		return false
+	}
+
+	modified := false
+	for _, item := range inputArray {
+		message, ok := item.(map[string]any)
+		if !ok {
+			continue
+		}
+
+		content, ok := message["content"]
+		if !ok {
+			continue
+		}
+
+		// If content is already a string, no conversion needed
+		if _, isString := content.(string); isString {
+			continue
+		}
+
+		// If content is an array (AI SDK format), convert to string
+		contentArray, ok := content.([]any)
+		if !ok {
+			continue
+		}
+
+		// Extract text from content array
+		var textParts []string
+		for _, part := range contentArray {
+			partMap, ok := part.(map[string]any)
+			if !ok {
+				continue
+			}
+
+			// Handle different content types
+			partType, _ := partMap["type"].(string)
+			switch partType {
+			case "input_text", "text":
+				// Extract text from input_text or text type
+				if text, ok := partMap["text"].(string); ok {
+					textParts = append(textParts, text)
+				}
+			case "input_image", "image":
+				// For images, we need to preserve the original format
+				// as ChatGPT Codex API may support images in a different way
+				// For now, skip image parts (they will be lost in conversion)
+				// TODO: Consider preserving image data or handling it separately
+				continue
+			case "input_file", "file":
+				// Similar to images, file inputs may need special handling
+				continue
+			default:
+				// For unknown types, try to extract text if available
+				if text, ok := partMap["text"].(string); ok {
+					textParts = append(textParts, text)
+				}
+			}
+		}
+
+		// Convert content array to string
+		if len(textParts) > 0 {
+			message["content"] = strings.Join(textParts, "\n")
+			modified = true
+		}
+	}
+
+	return modified
+}
+
 // OpenAIRecordUsageInput input for recording usage
 type OpenAIRecordUsageInput struct {
 	Result       *OpenAIForwardResult

backend/internal/service/proxy_service.go

@@ -20,6 +20,7 @@ type ProxyRepository interface {
 
 	List(ctx context.Context, params pagination.PaginationParams) ([]Proxy, *pagination.PaginationResult, error)
 	ListWithFilters(ctx context.Context, params pagination.PaginationParams, protocol, status, search string) ([]Proxy, *pagination.PaginationResult, error)
+	ListWithFiltersAndAccountCount(ctx context.Context, params pagination.PaginationParams, protocol, status, search string) ([]ProxyWithAccountCount, *pagination.PaginationResult, error)
 	ListActive(ctx context.Context) ([]Proxy, error)
 	ListActiveWithAccountCount(ctx context.Context) ([]ProxyWithAccountCount, error)
 

backend/migrations/029_add_group_claude_code_restriction.sql

@@ -0,0 +1,21 @@
+-- 029_add_group_claude_code_restriction.sql
+-- 添加分组级别的 Claude Code 客户端限制功能
+
+-- 添加 claude_code_only 字段：是否仅允许 Claude Code 客户端
+ALTER TABLE groups
+ADD COLUMN IF NOT EXISTS claude_code_only BOOLEAN NOT NULL DEFAULT FALSE;
+
+-- 添加 fallback_group_id 字段：非 Claude Code 请求降级到的分组
+ALTER TABLE groups
+ADD COLUMN IF NOT EXISTS fallback_group_id BIGINT REFERENCES groups(id) ON DELETE SET NULL;
+
+-- 添加索引优化查询
+CREATE INDEX IF NOT EXISTS idx_groups_claude_code_only
+ON groups(claude_code_only) WHERE deleted_at IS NULL;
+
+CREATE INDEX IF NOT EXISTS idx_groups_fallback_group_id
+ON groups(fallback_group_id) WHERE deleted_at IS NULL AND fallback_group_id IS NOT NULL;
+
+-- 添加字段注释
+COMMENT ON COLUMN groups.claude_code_only IS '是否仅允许 Claude Code 客户端访问此分组';
+COMMENT ON COLUMN groups.fallback_group_id IS '非 Claude Code 请求降级使用的分组 ID';

frontend/src/components/account/CreateAccountModal.vue

@@ -166,7 +166,7 @@
           >
             <div
               :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
+                'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                 accountCategory === 'oauth-based'
                   ? 'bg-orange-500 text-white'
                   : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -196,7 +196,7 @@
           >
             <div
               :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
+                'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                 accountCategory === 'apikey'
                   ? 'bg-purple-500 text-white'
                   : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -232,7 +232,7 @@
           >
             <div
               :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
+                'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                 accountCategory === 'oauth-based'
                   ? 'bg-green-500 text-white'
                   : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -258,7 +258,7 @@
           >
             <div
               :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
+                'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                 accountCategory === 'apikey'
                   ? 'bg-purple-500 text-white'
                   : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -302,7 +302,7 @@
           >
             <div
               :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
+                'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                 accountCategory === 'oauth-based'
                   ? 'bg-blue-500 text-white'
                   : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -332,7 +332,7 @@
           >
             <div
               :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
+                'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                 accountCategory === 'apikey'
                   ? 'bg-purple-500 text-white'
                   : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -397,7 +397,7 @@
             >
               <div
                 :class="[
-                  'flex h-8 w-8 items-center justify-center rounded-lg',
+                  'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                   geminiOAuthType === 'google_one'
                     ? 'bg-purple-500 text-white'
                     : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -440,7 +440,7 @@
             >
               <div
                 :class="[
-                  'flex h-8 w-8 items-center justify-center rounded-lg',
+                  'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                   geminiOAuthType === 'code_assist'
                     ? 'bg-blue-500 text-white'
                     : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -518,7 +518,7 @@
             >
               <div
                 :class="[
-                  'flex h-8 w-8 items-center justify-center rounded-lg',
+                  'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
                   geminiOAuthType === 'ai_studio'
                     ? 'bg-amber-500 text-white'
                     : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
@@ -621,7 +621,7 @@
           <div
             class="flex items-center gap-3 rounded-lg border-2 border-purple-500 bg-purple-50 p-3 dark:bg-purple-900/20"
           >
-            <div class="flex h-8 w-8 items-center justify-center rounded-lg bg-purple-500 text-white">
+            <div class="flex h-8 w-8 shrink-0 items-center justify-center rounded-lg bg-purple-500 text-white">
               <Icon name="key" size="sm" />
             </div>
             <div>

frontend/src/components/account/ReAuthAccountModal.vue

@@ -73,113 +73,48 @@
         </div>
       </fieldset>
 
-      <!-- Gemini OAuth Type Selection -->
-      <fieldset v-if="isGemini" class="border-0 p-0">
-        <legend class="input-label">{{ t('admin.accounts.oauth.gemini.oauthTypeLabel') }}</legend>
-        <div class="mt-2 grid grid-cols-3 gap-3">
-          <button
-            type="button"
-            @click="handleSelectGeminiOAuthType('google_one')"
-            :class="[
-              'flex items-center gap-3 rounded-lg border-2 p-3 text-left transition-all',
-              geminiOAuthType === 'google_one'
-                ? 'border-purple-500 bg-purple-50 dark:bg-purple-900/20'
-                : 'border-gray-200 hover:border-purple-300 dark:border-dark-600 dark:hover:border-purple-700'
-            ]"
-          >
-            <div
-              :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
-                geminiOAuthType === 'google_one'
-                  ? 'bg-purple-500 text-white'
-                  : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
-              ]"
-            >
-              <svg class="h-4 w-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" stroke-width="1.5">
-                <path stroke-linecap="round" stroke-linejoin="round" d="M15.75 6a3.75 3.75 0 11-7.5 0 3.75 3.75 0 017.5 0zM4.501 20.118a7.5 7.5 0 0114.998 0A17.933 17.933 0 0112 21.75c-2.676 0-5.216-.584-7.499-1.632z" />
-              </svg>
-            </div>
-            <div class="min-w-0">
-              <span class="block text-sm font-medium text-gray-900 dark:text-white">Google One</span>
-              <span class="text-xs text-gray-500 dark:text-gray-400">个人账号</span>
-            </div>
-          </button>
-
-          <button
-            type="button"
-            @click="handleSelectGeminiOAuthType('code_assist')"
-            :class="[
-              'flex items-center gap-3 rounded-lg border-2 p-3 text-left transition-all',
-              geminiOAuthType === 'code_assist'
-                ? 'border-blue-500 bg-blue-50 dark:bg-blue-900/20'
-                : 'border-gray-200 hover:border-blue-300 dark:border-dark-600 dark:hover:border-blue-700'
-            ]"
-          >
-            <div
-              :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
-                geminiOAuthType === 'code_assist'
-                  ? 'bg-blue-500 text-white'
-                  : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
-              ]"
-            >
-              <Icon name="cloud" size="sm" />
-            </div>
-            <div class="min-w-0">
-              <span class="block text-sm font-medium text-gray-900 dark:text-white">
-                {{ t('admin.accounts.gemini.oauthType.builtInTitle') }}
-              </span>
-              <span class="text-xs text-gray-500 dark:text-gray-400">
-                {{ t('admin.accounts.gemini.oauthType.builtInDesc') }}
-              </span>
-            </div>
-          </button>
-
-          <button
-            type="button"
-            :disabled="!geminiAIStudioOAuthEnabled"
-            @click="handleSelectGeminiOAuthType('ai_studio')"
-            :class="[
-              'flex items-center gap-3 rounded-lg border-2 p-3 text-left transition-all',
-              !geminiAIStudioOAuthEnabled ? 'cursor-not-allowed opacity-60' : '',
-              geminiOAuthType === 'ai_studio'
-                ? 'border-purple-500 bg-purple-50 dark:bg-purple-900/20'
-                : 'border-gray-200 hover:border-purple-300 dark:border-dark-600 dark:hover:border-purple-700'
-            ]"
-          >
-            <div
-              :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
-                geminiOAuthType === 'ai_studio'
-                  ? 'bg-purple-500 text-white'
-                  : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
-              ]"
-            >
-              <Icon name="sparkles" size="sm" />
-            </div>
-            <div class="min-w-0">
-              <span class="block text-sm font-medium text-gray-900 dark:text-white">
-                {{ t('admin.accounts.gemini.oauthType.customTitle') }}
-              </span>
-              <span class="text-xs text-gray-500 dark:text-gray-400">
-                {{ t('admin.accounts.gemini.oauthType.customDesc') }}
-              </span>
-              <div v-if="!geminiAIStudioOAuthEnabled" class="group relative mt-1 inline-block">
-                <span
-                  class="rounded bg-amber-100 px-2 py-0.5 text-xs text-amber-700 dark:bg-amber-900/30 dark:text-amber-300"
-                >
-                  {{ t('admin.accounts.oauth.gemini.aiStudioNotConfiguredShort') }}
-                </span>
-                <div
-                  class="pointer-events-none absolute left-0 top-full z-10 mt-2 w-[28rem] rounded-md border border-amber-200 bg-amber-50 px-3 py-2 text-xs text-amber-800 opacity-0 shadow-sm transition-opacity group-hover:opacity-100 dark:border-amber-700 dark:bg-amber-900/40 dark:text-amber-200"
-                >
-                  {{ t('admin.accounts.oauth.gemini.aiStudioNotConfiguredTip') }}
-                </div>
-              </div>
-            </div>
-          </button>
+      <!-- Gemini OAuth Type Display (read-only) -->
+      <div v-if="isGemini" class="rounded-lg border border-gray-200 bg-gray-50 p-4 dark:border-dark-600 dark:bg-dark-700">
+        <div class="mb-2 text-sm font-medium text-gray-700 dark:text-gray-300">
+          {{ t('admin.accounts.oauth.gemini.oauthTypeLabel') }}
         </div>
-      </fieldset>
+        <div class="flex items-center gap-3">
+          <div
+            :class="[
+              'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
+              geminiOAuthType === 'google_one'
+                ? 'bg-purple-500 text-white'
+                : geminiOAuthType === 'code_assist'
+                  ? 'bg-blue-500 text-white'
+                  : 'bg-amber-500 text-white'
+            ]"
+          >
+            <Icon v-if="geminiOAuthType === 'google_one'" name="user" size="sm" />
+            <Icon v-else-if="geminiOAuthType === 'code_assist'" name="cloud" size="sm" />
+            <Icon v-else name="sparkles" size="sm" />
+          </div>
+          <div>
+            <span class="block text-sm font-medium text-gray-900 dark:text-white">
+              {{
+                geminiOAuthType === 'google_one'
+                  ? 'Google One'
+                  : geminiOAuthType === 'code_assist'
+                    ? t('admin.accounts.gemini.oauthType.builtInTitle')
+                    : t('admin.accounts.gemini.oauthType.customTitle')
+              }}
+            </span>
+            <span class="text-xs text-gray-500 dark:text-gray-400">
+              {{
+                geminiOAuthType === 'google_one'
+                  ? '个人账号'
+                  : geminiOAuthType === 'code_assist'
+                    ? t('admin.accounts.gemini.oauthType.builtInDesc')
+                    : t('admin.accounts.gemini.oauthType.customDesc')
+              }}
+            </span>
+          </div>
+        </div>
+      </div>
 
       <OAuthAuthorizationFlow
         ref="oauthFlowRef"
@@ -299,7 +234,6 @@ const oauthFlowRef = ref<OAuthFlowExposed | null>(null)
 // State
 const addMethod = ref<AddMethod>('oauth')
 const geminiOAuthType = ref<'code_assist' | 'google_one' | 'ai_studio'>('code_assist')
-const geminiAIStudioOAuthEnabled = ref(false)
 
 // Computed - check platform
 const isOpenAI = computed(() => props.account?.platform === 'openai')
@@ -367,14 +301,6 @@ watch(
               ? 'ai_studio'
               : 'code_assist'
       }
-      if (isGemini.value) {
-        geminiOAuth.getCapabilities().then((caps) => {
-          geminiAIStudioOAuthEnabled.value = !!caps?.ai_studio_oauth_enabled
-          if (!geminiAIStudioOAuthEnabled.value && geminiOAuthType.value === 'ai_studio') {
-            geminiOAuthType.value = 'code_assist'
-          }
-        })
-      }
     } else {
       resetState()
     }
@@ -385,7 +311,6 @@ watch(
 const resetState = () => {
   addMethod.value = 'oauth'
   geminiOAuthType.value = 'code_assist'
-  geminiAIStudioOAuthEnabled.value = false
   claudeOAuth.resetState()
   openaiOAuth.resetState()
   geminiOAuth.resetState()
@@ -393,14 +318,6 @@ const resetState = () => {
   oauthFlowRef.value?.reset()
 }
 
-const handleSelectGeminiOAuthType = (oauthType: 'code_assist' | 'google_one' | 'ai_studio') => {
-  if (oauthType === 'ai_studio' && !geminiAIStudioOAuthEnabled.value) {
-    appStore.showError(t('admin.accounts.oauth.gemini.aiStudioNotConfigured'))
-    return
-  }
-  geminiOAuthType.value = oauthType
-}
-
 const handleClose = () => {
   emit('close')
 }

frontend/src/components/admin/account/ReAuthAccountModal.vue

@@ -73,111 +73,48 @@
         </div>
       </fieldset>
 
-      <!-- Gemini OAuth Type Selection -->
-      <fieldset v-if="isGemini" class="border-0 p-0">
-        <legend class="input-label">{{ t('admin.accounts.oauth.gemini.oauthTypeLabel') }}</legend>
-        <div class="mt-2 grid grid-cols-3 gap-3">
-          <button
-            type="button"
-            @click="handleSelectGeminiOAuthType('google_one')"
-            :class="[
-              'flex items-center gap-3 rounded-lg border-2 p-3 text-left transition-all',
-              geminiOAuthType === 'google_one'
-                ? 'border-purple-500 bg-purple-50 dark:bg-purple-900/20'
-                : 'border-gray-200 hover:border-purple-300 dark:border-dark-600 dark:hover:border-purple-700'
-            ]"
-          >
-            <div
-              :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
-                geminiOAuthType === 'google_one'
-                  ? 'bg-purple-500 text-white'
-                  : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
-              ]"
-            >
-              <Icon name="user" size="sm" />
-            </div>
-            <div class="min-w-0">
-              <span class="block text-sm font-medium text-gray-900 dark:text-white">Google One</span>
-              <span class="text-xs text-gray-500 dark:text-gray-400">个人账号</span>
-            </div>
-          </button>
-
-          <button
-            type="button"
-            @click="handleSelectGeminiOAuthType('code_assist')"
-            :class="[
-              'flex items-center gap-3 rounded-lg border-2 p-3 text-left transition-all',
-              geminiOAuthType === 'code_assist'
-                ? 'border-blue-500 bg-blue-50 dark:bg-blue-900/20'
-                : 'border-gray-200 hover:border-blue-300 dark:border-dark-600 dark:hover:border-blue-700'
-            ]"
-          >
-            <div
-              :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
-                geminiOAuthType === 'code_assist'
-                  ? 'bg-blue-500 text-white'
-                  : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
-              ]"
-            >
-              <Icon name="cloud" size="sm" />
-            </div>
-            <div class="min-w-0">
-              <span class="block text-sm font-medium text-gray-900 dark:text-white">
-                {{ t('admin.accounts.gemini.oauthType.builtInTitle') }}
-              </span>
-              <span class="text-xs text-gray-500 dark:text-gray-400">
-                {{ t('admin.accounts.gemini.oauthType.builtInDesc') }}
-              </span>
-            </div>
-          </button>
-
-          <button
-            type="button"
-            :disabled="!geminiAIStudioOAuthEnabled"
-            @click="handleSelectGeminiOAuthType('ai_studio')"
-            :class="[
-              'flex items-center gap-3 rounded-lg border-2 p-3 text-left transition-all',
-              !geminiAIStudioOAuthEnabled ? 'cursor-not-allowed opacity-60' : '',
-              geminiOAuthType === 'ai_studio'
-                ? 'border-purple-500 bg-purple-50 dark:bg-purple-900/20'
-                : 'border-gray-200 hover:border-purple-300 dark:border-dark-600 dark:hover:border-purple-700'
-            ]"
-          >
-            <div
-              :class="[
-                'flex h-8 w-8 items-center justify-center rounded-lg',
-                geminiOAuthType === 'ai_studio'
-                  ? 'bg-purple-500 text-white'
-                  : 'bg-gray-100 text-gray-500 dark:bg-dark-600 dark:text-gray-400'
-              ]"
-            >
-              <Icon name="sparkles" size="sm" />
-            </div>
-            <div class="min-w-0">
-              <span class="block text-sm font-medium text-gray-900 dark:text-white">
-                {{ t('admin.accounts.gemini.oauthType.customTitle') }}
-              </span>
-              <span class="text-xs text-gray-500 dark:text-gray-400">
-                {{ t('admin.accounts.gemini.oauthType.customDesc') }}
-              </span>
-              <div v-if="!geminiAIStudioOAuthEnabled" class="group relative mt-1 inline-block">
-                <span
-                  class="rounded bg-amber-100 px-2 py-0.5 text-xs text-amber-700 dark:bg-amber-900/30 dark:text-amber-300"
-                >
-                  {{ t('admin.accounts.oauth.gemini.aiStudioNotConfiguredShort') }}
-                </span>
-                <div
-                  class="pointer-events-none absolute left-0 top-full z-10 mt-2 w-[28rem] rounded-md border border-amber-200 bg-amber-50 px-3 py-2 text-xs text-amber-800 opacity-0 shadow-sm transition-opacity group-hover:opacity-100 dark:border-amber-700 dark:bg-amber-900/40 dark:text-amber-200"
-                >
-                  {{ t('admin.accounts.oauth.gemini.aiStudioNotConfiguredTip') }}
-                </div>
-              </div>
-            </div>
-          </button>
+      <!-- Gemini OAuth Type Display (read-only) -->
+      <div v-if="isGemini" class="rounded-lg border border-gray-200 bg-gray-50 p-4 dark:border-dark-600 dark:bg-dark-700">
+        <div class="mb-2 text-sm font-medium text-gray-700 dark:text-gray-300">
+          {{ t('admin.accounts.oauth.gemini.oauthTypeLabel') }}
         </div>
-      </fieldset>
+        <div class="flex items-center gap-3">
+          <div
+            :class="[
+              'flex h-8 w-8 shrink-0 items-center justify-center rounded-lg',
+              geminiOAuthType === 'google_one'
+                ? 'bg-purple-500 text-white'
+                : geminiOAuthType === 'code_assist'
+                  ? 'bg-blue-500 text-white'
+                  : 'bg-amber-500 text-white'
+            ]"
+          >
+            <Icon v-if="geminiOAuthType === 'google_one'" name="user" size="sm" />
+            <Icon v-else-if="geminiOAuthType === 'code_assist'" name="cloud" size="sm" />
+            <Icon v-else name="sparkles" size="sm" />
+          </div>
+          <div>
+            <span class="block text-sm font-medium text-gray-900 dark:text-white">
+              {{
+                geminiOAuthType === 'google_one'
+                  ? 'Google One'
+                  : geminiOAuthType === 'code_assist'
+                    ? t('admin.accounts.gemini.oauthType.builtInTitle')
+                    : t('admin.accounts.gemini.oauthType.customTitle')
+              }}
+            </span>
+            <span class="text-xs text-gray-500 dark:text-gray-400">
+              {{
+                geminiOAuthType === 'google_one'
+                  ? '个人账号'
+                  : geminiOAuthType === 'code_assist'
+                    ? t('admin.accounts.gemini.oauthType.builtInDesc')
+                    : t('admin.accounts.gemini.oauthType.customDesc')
+              }}
+            </span>
+          </div>
+        </div>
+      </div>
 
       <OAuthAuthorizationFlow
         ref="oauthFlowRef"
@@ -297,7 +234,6 @@ const oauthFlowRef = ref<OAuthFlowExposed | null>(null)
 // State
 const addMethod = ref<AddMethod>('oauth')
 const geminiOAuthType = ref<'code_assist' | 'google_one' | 'ai_studio'>('code_assist')
-const geminiAIStudioOAuthEnabled = ref(false)
 
 // Computed - check platform
 const isOpenAI = computed(() => props.account?.platform === 'openai')
@@ -365,14 +301,6 @@ watch(
               ? 'ai_studio'
               : 'code_assist'
       }
-      if (isGemini.value) {
-        geminiOAuth.getCapabilities().then((caps) => {
-          geminiAIStudioOAuthEnabled.value = !!caps?.ai_studio_oauth_enabled
-          if (!geminiAIStudioOAuthEnabled.value && geminiOAuthType.value === 'ai_studio') {
-            geminiOAuthType.value = 'code_assist'
-          }
-        })
-      }
     } else {
       resetState()
     }
@@ -383,7 +311,6 @@ watch(
 const resetState = () => {
   addMethod.value = 'oauth'
   geminiOAuthType.value = 'code_assist'
-  geminiAIStudioOAuthEnabled.value = false
   claudeOAuth.resetState()
   openaiOAuth.resetState()
   geminiOAuth.resetState()
@@ -391,14 +318,6 @@ const resetState = () => {
   oauthFlowRef.value?.reset()
 }
 
-const handleSelectGeminiOAuthType = (oauthType: 'code_assist' | 'google_one' | 'ai_studio') => {
-  if (oauthType === 'ai_studio' && !geminiAIStudioOAuthEnabled.value) {
-    appStore.showError(t('admin.accounts.oauth.gemini.aiStudioNotConfigured'))
-    return
-  }
-  geminiOAuthType.value = oauthType
-}
-
 const handleClose = () => {
   emit('close')
 }

frontend/src/components/admin/usage/UsageTable.vue

@@ -115,15 +115,9 @@
           <span class="text-sm text-gray-600 dark:text-gray-400">{{ formatDateTime(value) }}</span>
         </template>
 
-        <template #cell-request_id="{ row }">
-          <div v-if="row.request_id" class="flex items-center gap-1.5 max-w-[120px]">
-            <span class="font-mono text-xs text-gray-500 dark:text-gray-400 truncate" :title="row.request_id">{{ row.request_id }}</span>
-            <button @click="copyRequestId(row.request_id)" class="flex-shrink-0 rounded p-0.5 transition-colors hover:bg-gray-100 dark:hover:bg-dark-700" :class="copiedRequestId === row.request_id ? 'text-green-500' : 'text-gray-400 hover:text-gray-600 dark:hover:text-gray-300'" :title="copiedRequestId === row.request_id ? t('keys.copied') : t('keys.copyToClipboard')">
-              <svg v-if="copiedRequestId === row.request_id" class="h-3.5 w-3.5" fill="none" stroke="currentColor" viewBox="0 0 24 24" stroke-width="2"><path stroke-linecap="round" stroke-linejoin="round" d="M5 13l4 4L19 7" /></svg>
-              <Icon v-else name="copy" size="sm" class="h-3.5 w-3.5" />
-            </button>
-          </div>
-          <span v-else class="text-gray-400 dark:text-gray-500">-</span>
+        <template #cell-user_agent="{ row }">
+          <span v-if="row.user_agent" class="text-sm text-gray-600 dark:text-gray-400 max-w-[150px] truncate block" :title="row.user_agent">{{ formatUserAgent(row.user_agent) }}</span>
+          <span v-else class="text-sm text-gray-400 dark:text-gray-500">-</span>
         </template>
 
         <template #empty><EmptyState :message="t('usage.noRecords')" /></template>
@@ -228,7 +222,6 @@
 import { ref, computed } from 'vue'
 import { useI18n } from 'vue-i18n'
 import { formatDateTime } from '@/utils/format'
-import { useAppStore } from '@/stores/app'
 import DataTable from '@/components/common/DataTable.vue'
 import EmptyState from '@/components/common/EmptyState.vue'
 import Icon from '@/components/icons/Icon.vue'
@@ -236,8 +229,6 @@ import type { UsageLog } from '@/types'
 
 defineProps(['data', 'loading'])
 const { t } = useI18n()
-const appStore = useAppStore()
-const copiedRequestId = ref<string | null>(null)
 
 // Tooltip state - cost
 const tooltipVisible = ref(false)
@@ -262,7 +253,7 @@ const cols = computed(() => [
   { key: 'first_token', label: t('usage.firstToken'), sortable: false },
   { key: 'duration', label: t('usage.duration'), sortable: false },
   { key: 'created_at', label: t('usage.time'), sortable: true },
-  { key: 'request_id', label: t('admin.usage.requestId'), sortable: false }
+  { key: 'user_agent', label: t('usage.userAgent'), sortable: false }
 ])
 
 const formatCacheTokens = (tokens: number): string => {
@@ -271,23 +262,25 @@ const formatCacheTokens = (tokens: number): string => {
   return tokens.toString()
 }
 
+const formatUserAgent = (ua: string): string => {
+  // 提取主要客户端标识
+  if (ua.includes('claude-cli')) return ua.match(/claude-cli\/[\d.]+/)?.[0] || 'Claude CLI'
+  if (ua.includes('Cursor')) return 'Cursor'
+  if (ua.includes('VSCode') || ua.includes('vscode')) return 'VS Code'
+  if (ua.includes('Continue')) return 'Continue'
+  if (ua.includes('Cline')) return 'Cline'
+  if (ua.includes('OpenAI')) return 'OpenAI SDK'
+  if (ua.includes('anthropic')) return 'Anthropic SDK'
+  // 截断过长的 UA
+  return ua.length > 30 ? ua.substring(0, 30) + '...' : ua
+}
+
 const formatDuration = (ms: number | null | undefined): string => {
   if (ms == null) return '-'
   if (ms < 1000) return `${ms}ms`
   return `${(ms / 1000).toFixed(2)}s`
 }
 
-const copyRequestId = async (requestId: string) => {
-  try {
-    await navigator.clipboard.writeText(requestId)
-    copiedRequestId.value = requestId
-    appStore.showSuccess(t('admin.usage.requestIdCopied'))
-    setTimeout(() => { copiedRequestId.value = null }, 2000)
-  } catch {
-    appStore.showError(t('common.copyFailed'))
-  }
-}
-
 // Cost tooltip functions
 const showTooltip = (event: MouseEvent, row: UsageLog) => {
   const target = event.currentTarget as HTMLElement

frontend/src/i18n/locales/en.ts

@@ -424,7 +424,8 @@ export default {
     billingType: 'Billing',
     balance: 'Balance',
     subscription: 'Subscription',
-    imageUnit: ' images'
+    imageUnit: ' images',
+    userAgent: 'User-Agent'
   },
 
   // Redeem
@@ -856,6 +857,15 @@ export default {
       imagePricing: {
         title: 'Image Generation Pricing',
         description: 'Configure pricing for gemini-3-pro-image model. Leave empty to use default prices.'
+      },
+      claudeCode: {
+        title: 'Claude Code Client Restriction',
+        tooltip: 'When enabled, this group only allows official Claude Code clients. Non-Claude Code requests will be rejected or fallback to the specified group.',
+        enabled: 'Claude Code Only',
+        disabled: 'Allow All Clients',
+        fallbackGroup: 'Fallback Group',
+        fallbackHint: 'Non-Claude Code requests will use this group. Leave empty to reject directly.',
+        noFallback: 'No Fallback (Reject)'
       }
     },
 
@@ -1560,6 +1570,7 @@ export default {
         protocol: 'Protocol',
         address: 'Address',
         status: 'Status',
+        accounts: 'Accounts',
         actions: 'Actions'
       },
       testConnection: 'Test Connection',

frontend/src/i18n/locales/zh.ts

@@ -421,7 +421,8 @@ export default {
     billingType: '消费类型',
     balance: '余额',
     subscription: '订阅',
-    imageUnit: '张'
+    imageUnit: '张',
+    userAgent: 'User-Agent'
   },
 
   // Redeem
@@ -933,6 +934,15 @@ export default {
       imagePricing: {
         title: '图片生成计费',
         description: '配置 gemini-3-pro-image 模型的图片生成价格，留空则使用默认价格'
+      },
+      claudeCode: {
+        title: 'Claude Code 客户端限制',
+        tooltip: '启用后，此分组仅允许 Claude Code 官方客户端访问。非 Claude Code 请求将被拒绝或降级到指定分组。',
+        enabled: '仅限 Claude Code',
+        disabled: '允许所有客户端',
+        fallbackGroup: '降级分组',
+        fallbackHint: '非 Claude Code 请求将使用此分组，留空则直接拒绝',
+        noFallback: '不降级（直接拒绝）'
       }
     },
 
@@ -1646,6 +1656,7 @@ export default {
         protocol: '协议',
         address: '地址',
         status: '状态',
+        accounts: '账号数',
         actions: '操作',
         nameLabel: '名称',
         namePlaceholder: '请输入代理名称',

frontend/src/types/index.ts

@@ -263,6 +263,9 @@ export interface Group {
   image_price_1k: number | null
   image_price_2k: number | null
   image_price_4k: number | null
+  // Claude Code 客户端限制
+  claude_code_only: boolean
+  fallback_group_id: number | null
   account_count?: number
   created_at: string
   updated_at: string
@@ -298,6 +301,15 @@ export interface CreateGroupRequest {
   platform?: GroupPlatform
   rate_multiplier?: number
   is_exclusive?: boolean
+  subscription_type?: SubscriptionType
+  daily_limit_usd?: number | null
+  weekly_limit_usd?: number | null
+  monthly_limit_usd?: number | null
+  image_price_1k?: number | null
+  image_price_2k?: number | null
+  image_price_4k?: number | null
+  claude_code_only?: boolean
+  fallback_group_id?: number | null
 }
 
 export interface UpdateGroupRequest {
@@ -307,6 +319,15 @@ export interface UpdateGroupRequest {
   rate_multiplier?: number
   is_exclusive?: boolean
   status?: 'active' | 'inactive'
+  subscription_type?: SubscriptionType
+  daily_limit_usd?: number | null
+  weekly_limit_usd?: number | null
+  monthly_limit_usd?: number | null
+  image_price_1k?: number | null
+  image_price_2k?: number | null
+  image_price_4k?: number | null
+  claude_code_only?: boolean
+  fallback_group_id?: number | null
 }
 
 // ==================== Account & Proxy Types ====================
@@ -576,6 +597,9 @@ export interface UsageLog {
   image_count: number
   image_size: string | null
 
+  // User-Agent
+  user_agent: string | null
+
   created_at: string
 
   user?: User

frontend/src/views/HomeView.vue

@@ -61,7 +61,7 @@
           <!-- Login / Dashboard Button -->
           <router-link
             v-if="isAuthenticated"
-            to="/dashboard"
+            :to="dashboardPath"
             class="inline-flex items-center gap-1.5 rounded-full bg-gray-900 py-1 pl-1 pr-2.5 transition-colors hover:bg-gray-800 dark:bg-gray-800 dark:hover:bg-gray-700"
           >
             <span
@@ -114,7 +114,7 @@
             <!-- CTA Button -->
             <div>
               <router-link
-                :to="isAuthenticated ? '/dashboard' : '/login'"
+                :to="isAuthenticated ? dashboardPath : '/login'"
                 class="btn btn-primary px-8 py-3 text-base shadow-lg shadow-primary-500/30"
               >
                 {{ isAuthenticated ? t('home.goToDashboard') : t('home.getStarted') }}
@@ -416,6 +416,8 @@ const githubUrl = 'https://github.com/Wei-Shaw/sub2api'
 
 // Auth state
 const isAuthenticated = computed(() => authStore.isAuthenticated)
+const isAdmin = computed(() => authStore.isAdmin)
+const dashboardPath = computed(() => isAdmin.value ? '/admin/dashboard' : '/dashboard')
 const userInitial = computed(() => {
   const user = authStore.user
   if (!user || !user.email) return ''

frontend/src/views/admin/GroupsView.vue

@@ -403,6 +403,62 @@
           </div>
         </div>
 
+        <!-- Claude Code 客户端限制（仅 anthropic 平台） -->
+        <div v-if="createForm.platform === 'anthropic'" class="border-t pt-4">
+          <div class="mb-1.5 flex items-center gap-1">
+            <label class="text-sm font-medium text-gray-700 dark:text-gray-300">
+              {{ t('admin.groups.claudeCode.title') }}
+            </label>
+            <!-- Help Tooltip -->
+            <div class="group relative inline-flex">
+              <Icon
+                name="questionCircle"
+                size="sm"
+                :stroke-width="2"
+                class="cursor-help text-gray-400 transition-colors hover:text-primary-500 dark:text-gray-500 dark:hover:text-primary-400"
+              />
+              <div class="pointer-events-none absolute bottom-full left-0 z-50 mb-2 w-72 opacity-0 transition-all duration-200 group-hover:pointer-events-auto group-hover:opacity-100">
+                <div class="rounded-lg bg-gray-900 p-3 text-white shadow-lg dark:bg-gray-800">
+                  <p class="text-xs leading-relaxed text-gray-300">
+                    {{ t('admin.groups.claudeCode.tooltip') }}
+                  </p>
+                  <div class="absolute -bottom-1.5 left-3 h-3 w-3 rotate-45 bg-gray-900 dark:bg-gray-800"></div>
+                </div>
+              </div>
+            </div>
+          </div>
+          <div class="flex items-center gap-3">
+            <button
+              type="button"
+              @click="createForm.claude_code_only = !createForm.claude_code_only"
+              :class="[
+                'relative inline-flex h-6 w-11 items-center rounded-full transition-colors',
+                createForm.claude_code_only ? 'bg-primary-500' : 'bg-gray-300 dark:bg-dark-600'
+              ]"
+            >
+              <span
+                :class="[
+                  'inline-block h-4 w-4 transform rounded-full bg-white shadow transition-transform',
+                  createForm.claude_code_only ? 'translate-x-6' : 'translate-x-1'
+                ]"
+              />
+            </button>
+            <span class="text-sm text-gray-500 dark:text-gray-400">
+              {{ createForm.claude_code_only ? t('admin.groups.claudeCode.enabled') : t('admin.groups.claudeCode.disabled') }}
+            </span>
+          </div>
+          <!-- 降级分组选择（仅当启用 claude_code_only 时显示） -->
+          <div v-if="createForm.claude_code_only" class="mt-3">
+            <label class="input-label">{{ t('admin.groups.claudeCode.fallbackGroup') }}</label>
+            <Select
+              v-model="createForm.fallback_group_id"
+              :options="fallbackGroupOptions"
+              :placeholder="t('admin.groups.claudeCode.noFallback')"
+            />
+            <p class="input-hint">{{ t('admin.groups.claudeCode.fallbackHint') }}</p>
+          </div>
+        </div>
+
       </form>
 
       <template #footer>
@@ -648,6 +704,62 @@
           </div>
         </div>
 
+        <!-- Claude Code 客户端限制（仅 anthropic 平台） -->
+        <div v-if="editForm.platform === 'anthropic'" class="border-t pt-4">
+          <div class="mb-1.5 flex items-center gap-1">
+            <label class="text-sm font-medium text-gray-700 dark:text-gray-300">
+              {{ t('admin.groups.claudeCode.title') }}
+            </label>
+            <!-- Help Tooltip -->
+            <div class="group relative inline-flex">
+              <Icon
+                name="questionCircle"
+                size="sm"
+                :stroke-width="2"
+                class="cursor-help text-gray-400 transition-colors hover:text-primary-500 dark:text-gray-500 dark:hover:text-primary-400"
+              />
+              <div class="pointer-events-none absolute bottom-full left-0 z-50 mb-2 w-72 opacity-0 transition-all duration-200 group-hover:pointer-events-auto group-hover:opacity-100">
+                <div class="rounded-lg bg-gray-900 p-3 text-white shadow-lg dark:bg-gray-800">
+                  <p class="text-xs leading-relaxed text-gray-300">
+                    {{ t('admin.groups.claudeCode.tooltip') }}
+                  </p>
+                  <div class="absolute -bottom-1.5 left-3 h-3 w-3 rotate-45 bg-gray-900 dark:bg-gray-800"></div>
+                </div>
+              </div>
+            </div>
+          </div>
+          <div class="flex items-center gap-3">
+            <button
+              type="button"
+              @click="editForm.claude_code_only = !editForm.claude_code_only"
+              :class="[
+                'relative inline-flex h-6 w-11 items-center rounded-full transition-colors',
+                editForm.claude_code_only ? 'bg-primary-500' : 'bg-gray-300 dark:bg-dark-600'
+              ]"
+            >
+              <span
+                :class="[
+                  'inline-block h-4 w-4 transform rounded-full bg-white shadow transition-transform',
+                  editForm.claude_code_only ? 'translate-x-6' : 'translate-x-1'
+                ]"
+              />
+            </button>
+            <span class="text-sm text-gray-500 dark:text-gray-400">
+              {{ editForm.claude_code_only ? t('admin.groups.claudeCode.enabled') : t('admin.groups.claudeCode.disabled') }}
+            </span>
+          </div>
+          <!-- 降级分组选择（仅当启用 claude_code_only 时显示） -->
+          <div v-if="editForm.claude_code_only" class="mt-3">
+            <label class="input-label">{{ t('admin.groups.claudeCode.fallbackGroup') }}</label>
+            <Select
+              v-model="editForm.fallback_group_id"
+              :options="fallbackGroupOptionsForEdit"
+              :placeholder="t('admin.groups.claudeCode.noFallback')"
+            />
+            <p class="input-hint">{{ t('admin.groups.claudeCode.fallbackHint') }}</p>
+          </div>
+        </div>
+
       </form>
 
       <template #footer>
@@ -774,6 +886,35 @@ const subscriptionTypeOptions = computed(() => [
   { value: 'subscription', label: t('admin.groups.subscription.subscription') }
 ])
 
+// 降级分组选项（创建时）- 仅包含 anthropic 平台且未启用 claude_code_only 的分组
+const fallbackGroupOptions = computed(() => {
+  const options: { value: number | null; label: string }[] = [
+    { value: null, label: t('admin.groups.claudeCode.noFallback') }
+  ]
+  const eligibleGroups = groups.value.filter(
+    (g) => g.platform === 'anthropic' && !g.claude_code_only && g.status === 'active'
+  )
+  eligibleGroups.forEach((g) => {
+    options.push({ value: g.id, label: g.name })
+  })
+  return options
+})
+
+// 降级分组选项（编辑时）- 排除自身
+const fallbackGroupOptionsForEdit = computed(() => {
+  const options: { value: number | null; label: string }[] = [
+    { value: null, label: t('admin.groups.claudeCode.noFallback') }
+  ]
+  const currentId = editingGroup.value?.id
+  const eligibleGroups = groups.value.filter(
+    (g) => g.platform === 'anthropic' && !g.claude_code_only && g.status === 'active' && g.id !== currentId
+  )
+  eligibleGroups.forEach((g) => {
+    options.push({ value: g.id, label: g.name })
+  })
+  return options
+})
+
 const groups = ref<Group[]>([])
 const loading = ref(false)
 const searchQuery = ref('')
@@ -821,7 +962,10 @@ const createForm = reactive({
   // 图片生成计费配置（仅 antigravity 平台使用）
   image_price_1k: null as number | null,
   image_price_2k: null as number | null,
-  image_price_4k: null as number | null
+  image_price_4k: null as number | null,
+  // Claude Code 客户端限制（仅 anthropic 平台使用）
+  claude_code_only: false,
+  fallback_group_id: null as number | null
 })
 
 const editForm = reactive({
@@ -838,7 +982,10 @@ const editForm = reactive({
   // 图片生成计费配置（仅 antigravity 平台使用）
   image_price_1k: null as number | null,
   image_price_2k: null as number | null,
-  image_price_4k: null as number | null
+  image_price_4k: null as number | null,
+  // Claude Code 客户端限制（仅 anthropic 平台使用）
+  claude_code_only: false,
+  fallback_group_id: null as number | null
 })
 
 // 根据分组类型返回不同的删除确认消息
@@ -908,6 +1055,8 @@ const closeCreateModal = () => {
   createForm.image_price_1k = null
   createForm.image_price_2k = null
   createForm.image_price_4k = null
+  createForm.claude_code_only = false
+  createForm.fallback_group_id = null
 }
 
 const handleCreateGroup = async () => {
@@ -949,6 +1098,8 @@ const handleEdit = (group: Group) => {
   editForm.image_price_1k = group.image_price_1k
   editForm.image_price_2k = group.image_price_2k
   editForm.image_price_4k = group.image_price_4k
+  editForm.claude_code_only = group.claude_code_only || false
+  editForm.fallback_group_id = group.fallback_group_id
   showEditModal.value = true
 }
 
@@ -966,7 +1117,12 @@ const handleUpdateGroup = async () => {
 
   submitting.value = true
   try {
-    await adminAPI.groups.update(editingGroup.value.id, editForm)
+    // 转换 fallback_group_id: null -> 0 (后端使用 0 表示清除)
+    const payload = {
+      ...editForm,
+      fallback_group_id: editForm.fallback_group_id === null ? 0 : editForm.fallback_group_id
+    }
+    await adminAPI.groups.update(editingGroup.value.id, payload)
     appStore.showSuccess(t('admin.groups.groupUpdated'))
     closeEditModal()
     loadGroups()

frontend/src/views/admin/ProxiesView.vue

@@ -85,6 +85,14 @@
             </span>
           </template>
 
+          <template #cell-account_count="{ value }">
+            <span
+              class="inline-flex items-center rounded bg-gray-100 px-2 py-0.5 text-xs font-medium text-gray-800 dark:bg-dark-600 dark:text-gray-300"
+            >
+              {{ t('admin.groups.accountsCount', { count: value || 0 }) }}
+            </span>
+          </template>
+
           <template #cell-actions="{ row }">
             <div class="flex items-center gap-1">
               <button
@@ -534,6 +542,7 @@ const columns = computed<Column[]>(() => [
   { key: 'name', label: t('admin.proxies.columns.name'), sortable: true },
   { key: 'protocol', label: t('admin.proxies.columns.protocol'), sortable: true },
   { key: 'address', label: t('admin.proxies.columns.address'), sortable: false },
+  { key: 'account_count', label: t('admin.proxies.columns.accounts'), sortable: true },
   { key: 'status', label: t('admin.proxies.columns.status'), sortable: true },
   { key: 'actions', label: t('admin.proxies.columns.actions'), sortable: false }
 ])

frontend/src/views/admin/UsageView.vue

@@ -96,7 +96,7 @@ const exportToExcel = async () => {
         t('admin.usage.cacheReadCost'), t('admin.usage.cacheCreationCost'),
         t('usage.rate'), t('usage.original'), t('usage.billed'),
         t('usage.billingType'), t('usage.firstToken'), t('usage.duration'),
-        t('admin.usage.requestId')
+        t('admin.usage.requestId'), t('usage.userAgent')
       ]
       const rows = all.map(log => [
         log.created_at,
@@ -120,7 +120,8 @@ const exportToExcel = async () => {
         log.billing_type === 1 ? t('usage.subscription') : t('usage.balance'),
         log.first_token_ms ?? '',
         log.duration_ms,
-        log.request_id || ''
+        log.request_id || '',
+        log.user_agent || ''
       ])
       const ws = XLSX.utils.aoa_to_sheet([headers, ...rows])
       const wb = XLSX.utils.book_new()

frontend/src/views/user/UsageView.vue

@@ -308,6 +308,11 @@
             }}</span>
           </template>
 
+          <template #cell-user_agent="{ row }">
+            <span v-if="row.user_agent" class="text-sm text-gray-600 dark:text-gray-400 max-w-[150px] truncate block" :title="row.user_agent">{{ formatUserAgent(row.user_agent) }}</span>
+            <span v-else class="text-sm text-gray-400 dark:text-gray-500">-</span>
+          </template>
+
           <template #empty>
             <EmptyState :message="t('usage.noRecords')" />
           </template>
@@ -480,7 +485,8 @@ const columns = computed<Column[]>(() => [
   { key: 'billing_type', label: t('usage.billingType'), sortable: false },
   { key: 'first_token', label: t('usage.firstToken'), sortable: false },
   { key: 'duration', label: t('usage.duration'), sortable: false },
-  { key: 'created_at', label: t('usage.time'), sortable: true }
+  { key: 'created_at', label: t('usage.time'), sortable: true },
+  { key: 'user_agent', label: t('usage.userAgent'), sortable: false }
 ])
 
 const usageLogs = ref<UsageLog[]>([])
@@ -545,6 +551,19 @@ const formatDuration = (ms: number): string => {
   return `${(ms / 1000).toFixed(2)}s`
 }
 
+const formatUserAgent = (ua: string): string => {
+  // 提取主要客户端标识
+  if (ua.includes('claude-cli')) return ua.match(/claude-cli\/[\d.]+/)?.[0] || 'Claude CLI'
+  if (ua.includes('Cursor')) return 'Cursor'
+  if (ua.includes('VSCode') || ua.includes('vscode')) return 'VS Code'
+  if (ua.includes('Continue')) return 'Continue'
+  if (ua.includes('Cline')) return 'Cline'
+  if (ua.includes('OpenAI')) return 'OpenAI SDK'
+  if (ua.includes('anthropic')) return 'Anthropic SDK'
+  // 截断过长的 UA
+  return ua.length > 30 ? ua.substring(0, 30) + '...' : ua
+}
+
 const formatTokens = (value: number): string => {
   if (value >= 1_000_000_000) {
     return `${(value / 1_000_000_000).toFixed(2)}B`