feat(group): 添加 MCP XML 注入开关

- Group 新增 mcp_xml_inject 字段，控制 Antigravity 平台的 MCP XML 协议注入
- 默认启用，可在分组设置中关闭
- 修复 GetByKeyForAuth 遗漏查询 mcp_xml_inject 字段导致认证缓存值始终为 false 的问题

backend/ent/group.go

@@ -62,6 +62,8 @@ type Group struct {
 	ModelRouting map[string][]int64 `json:"model_routing,omitempty"`
 	// 是否启用模型路由配置
 	ModelRoutingEnabled bool `json:"model_routing_enabled,omitempty"`
+	// 是否注入 MCP XML 调用协议提示词（仅 antigravity 平台）
+	McpXMLInject bool `json:"mcp_xml_inject,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"`
@@ -170,7 +172,7 @@ func (*Group) scanValues(columns []string) ([]any, error) {
 		switch columns[i] {
 		case group.FieldModelRouting:
 			values[i] = new([]byte)
-		case group.FieldIsExclusive, group.FieldClaudeCodeOnly, group.FieldModelRoutingEnabled:
+		case group.FieldIsExclusive, group.FieldClaudeCodeOnly, group.FieldModelRoutingEnabled, group.FieldMcpXMLInject:
 			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)
@@ -345,6 +347,12 @@ func (_m *Group) assignValues(columns []string, values []any) error {
 			} else if value.Valid {
 				_m.ModelRoutingEnabled = value.Bool
 			}
+		case group.FieldMcpXMLInject:
+			if value, ok := values[i].(*sql.NullBool); !ok {
+				return fmt.Errorf("unexpected type %T for field mcp_xml_inject", values[i])
+			} else if value.Valid {
+				_m.McpXMLInject = value.Bool
+			}
 		default:
 			_m.selectValues.Set(columns[i], values[i])
 		}
@@ -506,6 +514,9 @@ func (_m *Group) String() string {
 	builder.WriteString(", ")
 	builder.WriteString("model_routing_enabled=")
 	builder.WriteString(fmt.Sprintf("%v", _m.ModelRoutingEnabled))
+	builder.WriteString(", ")
+	builder.WriteString("mcp_xml_inject=")
+	builder.WriteString(fmt.Sprintf("%v", _m.McpXMLInject))
 	builder.WriteByte(')')
 	return builder.String()
 }

backend/ent/group/group.go

@@ -59,6 +59,8 @@ const (
 	FieldModelRouting = "model_routing"
 	// FieldModelRoutingEnabled holds the string denoting the model_routing_enabled field in the database.
 	FieldModelRoutingEnabled = "model_routing_enabled"
+	// FieldMcpXMLInject holds the string denoting the mcp_xml_inject field in the database.
+	FieldMcpXMLInject = "mcp_xml_inject"
 	// 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.
@@ -156,6 +158,7 @@ var Columns = []string{
 	FieldFallbackGroupIDOnInvalidRequest,
 	FieldModelRouting,
 	FieldModelRoutingEnabled,
+	FieldMcpXMLInject,
 }
 
 var (
@@ -215,6 +218,8 @@ var (
 	DefaultClaudeCodeOnly bool
 	// DefaultModelRoutingEnabled holds the default value on creation for the "model_routing_enabled" field.
 	DefaultModelRoutingEnabled bool
+	// DefaultMcpXMLInject holds the default value on creation for the "mcp_xml_inject" field.
+	DefaultMcpXMLInject bool
 )
 
 // OrderOption defines the ordering options for the Group queries.
@@ -330,6 +335,11 @@ func ByModelRoutingEnabled(opts ...sql.OrderTermOption) OrderOption {
 	return sql.OrderByField(FieldModelRoutingEnabled, opts...).ToFunc()
 }
 
+// ByMcpXMLInject orders the results by the mcp_xml_inject field.
+func ByMcpXMLInject(opts ...sql.OrderTermOption) OrderOption {
+	return sql.OrderByField(FieldMcpXMLInject, 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

@@ -160,6 +160,11 @@ func ModelRoutingEnabled(v bool) predicate.Group {
 	return predicate.Group(sql.FieldEQ(FieldModelRoutingEnabled, v))
 }
 
+// McpXMLInject applies equality check predicate on the "mcp_xml_inject" field. It's identical to McpXMLInjectEQ.
+func McpXMLInject(v bool) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldMcpXMLInject, 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))
@@ -1145,6 +1150,16 @@ func ModelRoutingEnabledNEQ(v bool) predicate.Group {
 	return predicate.Group(sql.FieldNEQ(FieldModelRoutingEnabled, v))
 }
 
+// McpXMLInjectEQ applies the EQ predicate on the "mcp_xml_inject" field.
+func McpXMLInjectEQ(v bool) predicate.Group {
+	return predicate.Group(sql.FieldEQ(FieldMcpXMLInject, v))
+}
+
+// McpXMLInjectNEQ applies the NEQ predicate on the "mcp_xml_inject" field.
+func McpXMLInjectNEQ(v bool) predicate.Group {
+	return predicate.Group(sql.FieldNEQ(FieldMcpXMLInject, v))
+}
+
 // 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

@@ -320,6 +320,20 @@ func (_c *GroupCreate) SetNillableModelRoutingEnabled(v *bool) *GroupCreate {
 	return _c
 }
 
+// SetMcpXMLInject sets the "mcp_xml_inject" field.
+func (_c *GroupCreate) SetMcpXMLInject(v bool) *GroupCreate {
+	_c.mutation.SetMcpXMLInject(v)
+	return _c
+}
+
+// SetNillableMcpXMLInject sets the "mcp_xml_inject" field if the given value is not nil.
+func (_c *GroupCreate) SetNillableMcpXMLInject(v *bool) *GroupCreate {
+	if v != nil {
+		_c.SetMcpXMLInject(*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...)
@@ -493,6 +507,10 @@ func (_c *GroupCreate) defaults() error {
 		v := group.DefaultModelRoutingEnabled
 		_c.mutation.SetModelRoutingEnabled(v)
 	}
+	if _, ok := _c.mutation.McpXMLInject(); !ok {
+		v := group.DefaultMcpXMLInject
+		_c.mutation.SetMcpXMLInject(v)
+	}
 	return nil
 }
 
@@ -551,6 +569,9 @@ func (_c *GroupCreate) check() error {
 	if _, ok := _c.mutation.ModelRoutingEnabled(); !ok {
 		return &ValidationError{Name: "model_routing_enabled", err: errors.New(`ent: missing required field "Group.model_routing_enabled"`)}
 	}
+	if _, ok := _c.mutation.McpXMLInject(); !ok {
+		return &ValidationError{Name: "mcp_xml_inject", err: errors.New(`ent: missing required field "Group.mcp_xml_inject"`)}
+	}
 	return nil
 }
 
@@ -666,6 +687,10 @@ func (_c *GroupCreate) createSpec() (*Group, *sqlgraph.CreateSpec) {
 		_spec.SetField(group.FieldModelRoutingEnabled, field.TypeBool, value)
 		_node.ModelRoutingEnabled = value
 	}
+	if value, ok := _c.mutation.McpXMLInject(); ok {
+		_spec.SetField(group.FieldMcpXMLInject, field.TypeBool, value)
+		_node.McpXMLInject = value
+	}
 	if nodes := _c.mutation.APIKeysIDs(); len(nodes) > 0 {
 		edge := &sqlgraph.EdgeSpec{
 			Rel:     sqlgraph.O2M,
@@ -1200,6 +1225,18 @@ func (u *GroupUpsert) UpdateModelRoutingEnabled() *GroupUpsert {
 	return u
 }
 
+// SetMcpXMLInject sets the "mcp_xml_inject" field.
+func (u *GroupUpsert) SetMcpXMLInject(v bool) *GroupUpsert {
+	u.Set(group.FieldMcpXMLInject, v)
+	return u
+}
+
+// UpdateMcpXMLInject sets the "mcp_xml_inject" field to the value that was provided on create.
+func (u *GroupUpsert) UpdateMcpXMLInject() *GroupUpsert {
+	u.SetExcluded(group.FieldMcpXMLInject)
+	return u
+}
+
 // UpdateNewValues updates the mutable fields using the new values that were set on create.
 // Using this option is equivalent to using:
 //
@@ -1686,6 +1723,20 @@ func (u *GroupUpsertOne) UpdateModelRoutingEnabled() *GroupUpsertOne {
 	})
 }
 
+// SetMcpXMLInject sets the "mcp_xml_inject" field.
+func (u *GroupUpsertOne) SetMcpXMLInject(v bool) *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.SetMcpXMLInject(v)
+	})
+}
+
+// UpdateMcpXMLInject sets the "mcp_xml_inject" field to the value that was provided on create.
+func (u *GroupUpsertOne) UpdateMcpXMLInject() *GroupUpsertOne {
+	return u.Update(func(s *GroupUpsert) {
+		s.UpdateMcpXMLInject()
+	})
+}
+
 // Exec executes the query.
 func (u *GroupUpsertOne) Exec(ctx context.Context) error {
 	if len(u.create.conflict) == 0 {
@@ -2338,6 +2389,20 @@ func (u *GroupUpsertBulk) UpdateModelRoutingEnabled() *GroupUpsertBulk {
 	})
 }
 
+// SetMcpXMLInject sets the "mcp_xml_inject" field.
+func (u *GroupUpsertBulk) SetMcpXMLInject(v bool) *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.SetMcpXMLInject(v)
+	})
+}
+
+// UpdateMcpXMLInject sets the "mcp_xml_inject" field to the value that was provided on create.
+func (u *GroupUpsertBulk) UpdateMcpXMLInject() *GroupUpsertBulk {
+	return u.Update(func(s *GroupUpsert) {
+		s.UpdateMcpXMLInject()
+	})
+}
+
 // Exec executes the query.
 func (u *GroupUpsertBulk) Exec(ctx context.Context) error {
 	if u.create.err != nil {

backend/ent/group_update.go

@@ -448,6 +448,20 @@ func (_u *GroupUpdate) SetNillableModelRoutingEnabled(v *bool) *GroupUpdate {
 	return _u
 }
 
+// SetMcpXMLInject sets the "mcp_xml_inject" field.
+func (_u *GroupUpdate) SetMcpXMLInject(v bool) *GroupUpdate {
+	_u.mutation.SetMcpXMLInject(v)
+	return _u
+}
+
+// SetNillableMcpXMLInject sets the "mcp_xml_inject" field if the given value is not nil.
+func (_u *GroupUpdate) SetNillableMcpXMLInject(v *bool) *GroupUpdate {
+	if v != nil {
+		_u.SetMcpXMLInject(*v)
+	}
+	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...)
@@ -874,6 +888,9 @@ func (_u *GroupUpdate) sqlSave(ctx context.Context) (_node int, err error) {
 	if value, ok := _u.mutation.ModelRoutingEnabled(); ok {
 		_spec.SetField(group.FieldModelRoutingEnabled, field.TypeBool, value)
 	}
+	if value, ok := _u.mutation.McpXMLInject(); ok {
+		_spec.SetField(group.FieldMcpXMLInject, field.TypeBool, value)
+	}
 	if _u.mutation.APIKeysCleared() {
 		edge := &sqlgraph.EdgeSpec{
 			Rel:     sqlgraph.O2M,
@@ -1602,6 +1619,20 @@ func (_u *GroupUpdateOne) SetNillableModelRoutingEnabled(v *bool) *GroupUpdateOn
 	return _u
 }
 
+// SetMcpXMLInject sets the "mcp_xml_inject" field.
+func (_u *GroupUpdateOne) SetMcpXMLInject(v bool) *GroupUpdateOne {
+	_u.mutation.SetMcpXMLInject(v)
+	return _u
+}
+
+// SetNillableMcpXMLInject sets the "mcp_xml_inject" field if the given value is not nil.
+func (_u *GroupUpdateOne) SetNillableMcpXMLInject(v *bool) *GroupUpdateOne {
+	if v != nil {
+		_u.SetMcpXMLInject(*v)
+	}
+	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...)
@@ -2058,6 +2089,9 @@ func (_u *GroupUpdateOne) sqlSave(ctx context.Context) (_node *Group, err error)
 	if value, ok := _u.mutation.ModelRoutingEnabled(); ok {
 		_spec.SetField(group.FieldModelRoutingEnabled, field.TypeBool, value)
 	}
+	if value, ok := _u.mutation.McpXMLInject(); ok {
+		_spec.SetField(group.FieldMcpXMLInject, field.TypeBool, value)
+	}
 	if _u.mutation.APIKeysCleared() {
 		edge := &sqlgraph.EdgeSpec{
 			Rel:     sqlgraph.O2M,

backend/ent/migrate/schema.go

@@ -229,6 +229,7 @@ var (
 		{Name: "fallback_group_id_on_invalid_request", Type: field.TypeInt64, Nullable: true},
 		{Name: "model_routing", Type: field.TypeJSON, Nullable: true, SchemaType: map[string]string{"postgres": "jsonb"}},
 		{Name: "model_routing_enabled", Type: field.TypeBool, Default: false},
+		{Name: "mcp_xml_inject", Type: field.TypeBool, Default: true},
 	}
 	// GroupsTable holds the schema information for the "groups" table.
 	GroupsTable = &schema.Table{

backend/ent/mutation.go

@@ -3868,6 +3868,7 @@ type GroupMutation struct {
 	addfallback_group_id_on_invalid_request *int64
 	model_routing                           *map[string][]int64
 	model_routing_enabled                   *bool
+	mcp_xml_inject                          *bool
 	clearedFields                           map[string]struct{}
 	api_keys                                map[int64]struct{}
 	removedapi_keys                         map[int64]struct{}
@@ -5133,6 +5134,42 @@ func (m *GroupMutation) ResetModelRoutingEnabled() {
 	m.model_routing_enabled = nil
 }
+// SetMcpXMLInject sets the "mcp_xml_inject" field.
+func (m *GroupMutation) SetMcpXMLInject(b bool) {
+	m.mcp_xml_inject = &b
+}
+
+// McpXMLInject returns the value of the "mcp_xml_inject" field in the mutation.
+func (m *GroupMutation) McpXMLInject() (r bool, exists bool) {
+	v := m.mcp_xml_inject
+	if v == nil {
+		return
+	}
+	return *v, true
+}
+
+// OldMcpXMLInject returns the old "mcp_xml_inject" 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) OldMcpXMLInject(ctx context.Context) (v bool, err error) {
+	if !m.op.Is(OpUpdateOne) {
+		return v, errors.New("OldMcpXMLInject is only allowed on UpdateOne operations")
+	}
+	if m.id == nil || m.oldValue == nil {
+		return v, errors.New("OldMcpXMLInject requires an ID field in the mutation")
+	}
+	oldValue, err := m.oldValue(ctx)
+	if err != nil {
+		return v, fmt.Errorf("querying old value for OldMcpXMLInject: %w", err)
+	}
+	return oldValue.McpXMLInject, nil
+}
+
+// ResetMcpXMLInject resets all changes to the "mcp_xml_inject" field.
+func (m *GroupMutation) ResetMcpXMLInject() {
+	m.mcp_xml_inject = nil
+}
+
 // AddAPIKeyIDs adds the "api_keys" edge to the APIKey entity by ids.
 func (m *GroupMutation) AddAPIKeyIDs(ids ...int64) {
 	if m.api_keys == nil {
@@ -5491,7 +5528,7 @@ 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, 22)
+	fields := make([]string, 0, 23)
 	if m.created_at != nil {
 		fields = append(fields, group.FieldCreatedAt)
 	}
@@ -5558,6 +5595,9 @@ func (m *GroupMutation) Fields() []string {
 	if m.model_routing_enabled != nil {
 		fields = append(fields, group.FieldModelRoutingEnabled)
 	}
+	if m.mcp_xml_inject != nil {
+		fields = append(fields, group.FieldMcpXMLInject)
+	}
 	return fields
 }
@@ -5610,6 +5650,8 @@ func (m *GroupMutation) Field(name string) (ent.Value, bool) {
 		return m.ModelRouting()
 	case group.FieldModelRoutingEnabled:
 		return m.ModelRoutingEnabled()
+	case group.FieldMcpXMLInject:
+		return m.McpXMLInject()
 	}
 	return nil, false
 }
@@ -5663,6 +5705,8 @@ func (m *GroupMutation) OldField(ctx context.Context, name string) (ent.Value, e
 		return m.OldModelRouting(ctx)
 	case group.FieldModelRoutingEnabled:
 		return m.OldModelRoutingEnabled(ctx)
+	case group.FieldMcpXMLInject:
+		return m.OldMcpXMLInject(ctx)
 	}
 	return nil, fmt.Errorf("unknown Group field %s", name)
 }
@@ -5826,6 +5870,13 @@ func (m *GroupMutation) SetField(name string, value ent.Value) error {
 		}
 		m.SetModelRoutingEnabled(v)
 		return nil
+	case group.FieldMcpXMLInject:
+		v, ok := value.(bool)
+		if !ok {
+			return fmt.Errorf("unexpected type %T for field %s", value, name)
+		}
+		m.SetMcpXMLInject(v)
+		return nil
 	}
 	return fmt.Errorf("unknown Group field %s", name)
 }
@@ -6133,6 +6184,9 @@ func (m *GroupMutation) ResetField(name string) error {
 	case group.FieldModelRoutingEnabled:
 		m.ResetModelRoutingEnabled()
 		return nil
+	case group.FieldMcpXMLInject:
+		m.ResetMcpXMLInject()
+		return nil
 	}
 	return fmt.Errorf("unknown Group field %s", name)
 }

backend/ent/runtime/runtime.go

@@ -284,6 +284,10 @@ func init() {
 	groupDescModelRoutingEnabled := groupFields[18].Descriptor()
 	// group.DefaultModelRoutingEnabled holds the default value on creation for the model_routing_enabled field.
 	group.DefaultModelRoutingEnabled = groupDescModelRoutingEnabled.Default.(bool)
+	// groupDescMcpXMLInject is the schema descriptor for mcp_xml_inject field.
+	groupDescMcpXMLInject := groupFields[19].Descriptor()
+	// group.DefaultMcpXMLInject holds the default value on creation for the mcp_xml_inject field.
+	group.DefaultMcpXMLInject = groupDescMcpXMLInject.Default.(bool)
 	promocodeFields := schema.PromoCode{}.Fields()
 	_ = promocodeFields
 	// promocodeDescCode is the schema descriptor for code field.

backend/ent/schema/group.go

@@ -110,6 +110,11 @@ func (Group) Fields() []ent.Field {
 		field.Bool("model_routing_enabled").
 			Default(false).
 			Comment("是否启用模型路由配置"),
+
+		// MCP XML 协议注入开关 (added by migration 042)
+		field.Bool("mcp_xml_inject").
+			Default(true).
+			Comment("是否注入 MCP XML 调用协议提示词（仅 antigravity 平台）"),
 	}
 }
 

backend/internal/handler/admin/group_handler.go

@@ -44,6 +44,7 @@ type CreateGroupRequest struct {
 	// 模型路由配置（仅 anthropic 平台使用）
 	ModelRouting        map[string][]int64 `json:"model_routing"`
 	ModelRoutingEnabled bool               `json:"model_routing_enabled"`
+	MCPXMLInject        *bool              `json:"mcp_xml_inject"`
 }
 
 // UpdateGroupRequest represents update group request
@@ -68,6 +69,7 @@ type UpdateGroupRequest struct {
 	// 模型路由配置（仅 anthropic 平台使用）
 	ModelRouting        map[string][]int64 `json:"model_routing"`
 	ModelRoutingEnabled *bool              `json:"model_routing_enabled"`
+	MCPXMLInject        *bool              `json:"mcp_xml_inject"`
 }
 
 // List handles listing all groups with pagination
@@ -174,6 +176,7 @@ func (h *GroupHandler) Create(c *gin.Context) {
 		FallbackGroupIDOnInvalidRequest: req.FallbackGroupIDOnInvalidRequest,
 		ModelRouting:                    req.ModelRouting,
 		ModelRoutingEnabled:             req.ModelRoutingEnabled,
+		MCPXMLInject:                    req.MCPXMLInject,
 	})
 	if err != nil {
 		response.ErrorFrom(c, err)
@@ -217,6 +220,7 @@ func (h *GroupHandler) Update(c *gin.Context) {
 		FallbackGroupIDOnInvalidRequest: req.FallbackGroupIDOnInvalidRequest,
 		ModelRouting:                    req.ModelRouting,
 		ModelRoutingEnabled:             req.ModelRoutingEnabled,
+		MCPXMLInject:                    req.MCPXMLInject,
 	})
 	if err != nil {
 		response.ErrorFrom(c, err)

backend/internal/handler/dto/mappers.go

@@ -92,6 +92,7 @@ func GroupFromServiceShallow(g *service.Group) *Group {
 		FallbackGroupIDOnInvalidRequest: g.FallbackGroupIDOnInvalidRequest,
 		ModelRouting:                    g.ModelRouting,
 		ModelRoutingEnabled:             g.ModelRoutingEnabled,
+		MCPXMLInject:                    g.MCPXMLInject,
 		CreatedAt:                       g.CreatedAt,
 		UpdatedAt:                       g.UpdatedAt,
 		AccountCount:                    g.AccountCount,

backend/internal/handler/dto/types.go

@@ -69,6 +69,9 @@ type Group struct {
 	ModelRouting        map[string][]int64 `json:"model_routing"`
 	ModelRoutingEnabled bool               `json:"model_routing_enabled"`
 
+	// MCP XML 协议注入（仅 antigravity 平台使用）
+	MCPXMLInject bool `json:"mcp_xml_inject"`
+
 	CreatedAt time.Time `json:"created_at"`
 	UpdatedAt time.Time `json:"updated_at"`
 

backend/internal/pkg/antigravity/request_transformer.go

@@ -44,11 +44,13 @@ type TransformOptions struct {
 	// IdentityPatch 可选：自定义注入到 systemInstruction 开头的身份防护提示词；
 	// 为空时使用默认模板（包含 [IDENTITY_PATCH] 及 SYSTEM_PROMPT_BEGIN 标记）。
 	IdentityPatch string
+	EnableMCPXML  bool
 }
 
 func DefaultTransformOptions() TransformOptions {
 	return TransformOptions{
 		EnableIdentityPatch: true,
+		EnableMCPXML:        true,
 	}
 }
 
@@ -257,8 +259,8 @@ func buildSystemInstruction(system json.RawMessage, modelName string, opts Trans
 	// 添加用户的 system prompt
 	parts = append(parts, userSystemParts...)
 
-	// 检测是否有 MCP 工具，如有则注入 XML 调用协议
-	if hasMCPTools(tools) {
+	// 检测是否有 MCP 工具，如有且启用了 MCP XML 注入则注入 XML 调用协议
+	if opts.EnableMCPXML && hasMCPTools(tools) {
 		parts = append(parts, GeminiPart{Text: mcpXMLProtocol})
 	}
 
@@ -491,7 +493,7 @@ func parseToolResultContent(content json.RawMessage, isError bool) string {
 
 // buildGenerationConfig 构建 generationConfig
 const (
-	defaultMaxOutputTokens   = 64000
+	defaultMaxOutputTokens    = 64000
 	maxOutputTokensUpperBound = 65000
 	maxOutputTokensClaude     = 64000
 )

backend/internal/repository/api_key_repo.go

@@ -139,6 +139,7 @@ func (r *apiKeyRepository) GetByKeyForAuth(ctx context.Context, key string) (*se
 				group.FieldFallbackGroupIDOnInvalidRequest,
 				group.FieldModelRoutingEnabled,
 				group.FieldModelRouting,
+				group.FieldMcpXMLInject,
 			)
 		}).
 		Only(ctx)
@@ -428,6 +429,7 @@ func groupEntityToService(g *dbent.Group) *service.Group {
 		FallbackGroupIDOnInvalidRequest: g.FallbackGroupIDOnInvalidRequest,
 		ModelRouting:                    g.ModelRouting,
 		ModelRoutingEnabled:             g.ModelRoutingEnabled,
+		MCPXMLInject:                    g.McpXMLInject,
 		CreatedAt:                       g.CreatedAt,
 		UpdatedAt:                       g.UpdatedAt,
 	}

backend/internal/repository/group_repo.go

@@ -51,7 +51,8 @@ func (r *groupRepository) Create(ctx context.Context, groupIn *service.Group) er
 		SetClaudeCodeOnly(groupIn.ClaudeCodeOnly).
 		SetNillableFallbackGroupID(groupIn.FallbackGroupID).
 		SetNillableFallbackGroupIDOnInvalidRequest(groupIn.FallbackGroupIDOnInvalidRequest).
-		SetModelRoutingEnabled(groupIn.ModelRoutingEnabled)
+		SetModelRoutingEnabled(groupIn.ModelRoutingEnabled).
+		SetMcpXMLInject(groupIn.MCPXMLInject)
 
 	// 设置模型路由配置
 	if groupIn.ModelRouting != nil {
@@ -109,7 +110,8 @@ func (r *groupRepository) Update(ctx context.Context, groupIn *service.Group) er
 		SetNillableImagePrice4k(groupIn.ImagePrice4K).
 		SetDefaultValidityDays(groupIn.DefaultValidityDays).
 		SetClaudeCodeOnly(groupIn.ClaudeCodeOnly).
-		SetModelRoutingEnabled(groupIn.ModelRoutingEnabled)
+		SetModelRoutingEnabled(groupIn.ModelRoutingEnabled).
+		SetMcpXMLInject(groupIn.MCPXMLInject)
 
 	// 处理 FallbackGroupID：nil 时清除，否则设置
 	if groupIn.FallbackGroupID != nil {

backend/internal/service/admin_service.go

@@ -113,6 +113,7 @@ type CreateGroupInput struct {
 	// 模型路由配置（仅 anthropic 平台使用）
 	ModelRouting        map[string][]int64
 	ModelRoutingEnabled bool // 是否启用模型路由
+	MCPXMLInject        *bool
 }
 
 type UpdateGroupInput struct {
@@ -137,6 +138,7 @@ type UpdateGroupInput struct {
 	// 模型路由配置（仅 anthropic 平台使用）
 	ModelRouting        map[string][]int64
 	ModelRoutingEnabled *bool // 是否启用模型路由
+	MCPXMLInject        *bool
 }
 
 type CreateAccountInput struct {
@@ -587,6 +589,12 @@ func (s *adminServiceImpl) CreateGroup(ctx context.Context, input *CreateGroupIn
 		}
 	}
 
+	// MCPXMLInject：默认为 true，仅当显式传入 false 时关闭
+	mcpXMLInject := true
+	if input.MCPXMLInject != nil {
+		mcpXMLInject = *input.MCPXMLInject
+	}
+
 	group := &Group{
 		Name:                            input.Name,
 		Description:                     input.Description,
@@ -605,6 +613,7 @@ func (s *adminServiceImpl) CreateGroup(ctx context.Context, input *CreateGroupIn
 		FallbackGroupID:                 input.FallbackGroupID,
 		FallbackGroupIDOnInvalidRequest: fallbackOnInvalidRequest,
 		ModelRouting:                    input.ModelRouting,
+		MCPXMLInject:                    mcpXMLInject,
 	}
 	if err := s.groupRepo.Create(ctx, group); err != nil {
 		return nil, err
@@ -785,6 +794,9 @@ func (s *adminServiceImpl) UpdateGroup(ctx context.Context, id int64, input *Upd
 	if input.ModelRoutingEnabled != nil {
 		group.ModelRoutingEnabled = *input.ModelRoutingEnabled
 	}
+	if input.MCPXMLInject != nil {
+		group.MCPXMLInject = *input.MCPXMLInject
+	}
 
 	if err := s.groupRepo.Update(ctx, group); err != nil {
 		return nil, err

backend/internal/service/antigravity_gateway_service.go

@@ -19,6 +19,7 @@ import (
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/pkg/antigravity"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
 	"github.com/gin-gonic/gin"
 	"github.com/google/uuid"
 )
@@ -552,6 +553,10 @@ func (s *AntigravityGatewayService) getClaudeTransformOptions(ctx context.Contex
 	}
 	opts.EnableIdentityPatch = s.settingService.IsIdentityPatchEnabled(ctx)
 	opts.IdentityPatch = s.settingService.GetIdentityPatchPrompt(ctx)
+
+	if group, ok := ctx.Value(ctxkey.Group).(*Group); ok && group != nil {
+		opts.EnableMCPXML = group.MCPXMLInject
+	}
 	return opts
 }
 

backend/internal/service/api_key_auth_cache.go

@@ -43,6 +43,7 @@ type APIKeyAuthGroupSnapshot struct {
 	// Only anthropic groups use these fields; others may leave them empty.
 	ModelRouting        map[string][]int64 `json:"model_routing,omitempty"`
 	ModelRoutingEnabled bool               `json:"model_routing_enabled"`
+	MCPXMLInject        bool               `json:"mcp_xml_inject"`
 }
 
 // APIKeyAuthCacheEntry 缓存条目，支持负缓存

backend/internal/service/api_key_auth_cache_impl.go

@@ -224,6 +224,7 @@ func (s *APIKeyService) snapshotFromAPIKey(apiKey *APIKey) *APIKeyAuthSnapshot {
 			FallbackGroupIDOnInvalidRequest: apiKey.Group.FallbackGroupIDOnInvalidRequest,
 			ModelRouting:                    apiKey.Group.ModelRouting,
 			ModelRoutingEnabled:             apiKey.Group.ModelRoutingEnabled,
+			MCPXMLInject:                    apiKey.Group.MCPXMLInject,
 		}
 	}
 	return snapshot
@@ -269,6 +270,7 @@ func (s *APIKeyService) snapshotToAPIKey(key string, snapshot *APIKeyAuthSnapsho
 			FallbackGroupIDOnInvalidRequest: snapshot.Group.FallbackGroupIDOnInvalidRequest,
 			ModelRouting:                    snapshot.Group.ModelRouting,
 			ModelRoutingEnabled:             snapshot.Group.ModelRoutingEnabled,
+			MCPXMLInject:                    snapshot.Group.MCPXMLInject,
 		}
 	}
 	return apiKey

backend/internal/service/group.go

@@ -38,6 +38,9 @@ type Group struct {
 	ModelRouting        map[string][]int64
 	ModelRoutingEnabled bool
 
+	// MCP XML 协议注入开关（仅 antigravity 平台使用）
+	MCPXMLInject bool
+
 	CreatedAt time.Time
 	UpdatedAt time.Time