diff --git a/backend/go.mod b/backend/go.mod
index 941f519d08..1c735301d6 100644
--- a/backend/go.mod
+++ b/backend/go.mod
@@ -19,6 +19,7 @@ require (
 	github.com/coder/websocket v1.8.14
 	github.com/dgraph-io/ristretto v0.2.0
 	github.com/gin-gonic/gin v1.9.1
+	github.com/go-playground/validator/v10 v10.14.0
 	github.com/go-webauthn/webauthn v0.17.4
 	github.com/golang-jwt/jwt/v5 v5.3.1
 	github.com/google/uuid v1.6.0
@@ -120,7 +121,6 @@ require (
 	github.com/go-openapi/inflect v0.19.0 // indirect
 	github.com/go-playground/locales v0.14.1 // indirect
 	github.com/go-playground/universal-translator v0.18.1 // indirect
-	github.com/go-playground/validator/v10 v10.14.0 // indirect
 	github.com/go-viper/mapstructure/v2 v2.5.0 // indirect
 	github.com/go-webauthn/x v0.2.6 // indirect
 	github.com/goccy/go-json v0.10.2 // indirect
diff --git a/backend/internal/domain/platforms.go b/backend/internal/domain/platforms.go
new file mode 100644
index 0000000000..f84801ad6b
--- /dev/null
+++ b/backend/internal/domain/platforms.go
@@ -0,0 +1,135 @@
+package domain
+
+// 平台清单：平台的单一数据来源。"所有平台"类列表（分组平台、用户额度、组合
+// 路由目标、调度快照、定价匹配等）与"某网关族"类列表都从这里派生；新增平台
+// 登记一条即可在这些位置生效，无需逐处修改或新增数据库约束迁移。
+//
+// 依赖具体实现的能力（OAuth、渠道监控、余额 / Coding Plan 探测、用量窗口、
+// Codex 模型目录等）仍由各自的代码显式列出，不在此处声明。
+
+// PlatformGateway 标识平台请求由哪个网关服务处理。
+type PlatformGateway string
+
+const (
+	// PlatformGatewayAnthropic 由 GatewayService 处理（Claude Messages 协议，以及 TypeSafe 的 /v1/systemone）。
+	PlatformGatewayAnthropic PlatformGateway = "anthropic"
+	// PlatformGatewayOpenAI 由 OpenAIGatewayService 处理（OpenAI、Grok 与多协议 API Key 供应商）。
+	PlatformGatewayOpenAI PlatformGateway = "openai"
+	// PlatformGatewayGemini 由 Gemini 兼容网关处理。
+	PlatformGatewayGemini PlatformGateway = "gemini"
+	// PlatformGatewayAntigravity 由 Antigravity 网关处理。
+	PlatformGatewayAntigravity PlatformGateway = "antigravity"
+)
+
+// PlatformSpec 描述一个具体（非 composite）平台。
+type PlatformSpec struct {
+	ID          string          `json:"id"`
+	DisplayName string          `json:"display_name"`
+	Gateway     PlatformGateway `json:"gateway"`
+	// CNProvider 标识国产单一厂商（Kimi / 智谱 / DeepSeek / MiniMax），共享国产
+	// 供应商的余额 / Coding Plan 等能力。
+	CNProvider bool `json:"cn_provider"`
+	// LiteLLMProvider 是定价目录中的 provider 名；空表示不支持从定价目录同步模型。
+	LiteLLMProvider string `json:"litellm_provider,omitempty"`
+}
+
+// platformList 的顺序即平台的展示顺序。
+var platformList = []PlatformSpec{
+	{ID: PlatformAnthropic, DisplayName: "Anthropic", Gateway: PlatformGatewayAnthropic, LiteLLMProvider: "anthropic"},
+	{ID: PlatformOpenAI, DisplayName: "OpenAI", Gateway: PlatformGatewayOpenAI, LiteLLMProvider: "openai"},
+	{ID: PlatformGemini, DisplayName: "Gemini", Gateway: PlatformGatewayGemini, LiteLLMProvider: "gemini"},
+	{ID: PlatformAntigravity, DisplayName: "Antigravity", Gateway: PlatformGatewayAntigravity, LiteLLMProvider: "anthropic"},
+	{ID: PlatformGrok, DisplayName: "Grok", Gateway: PlatformGatewayOpenAI, LiteLLMProvider: "xai"},
+	{ID: PlatformKimi, DisplayName: "Kimi", Gateway: PlatformGatewayOpenAI, CNProvider: true, LiteLLMProvider: "moonshot"},
+	{ID: PlatformZhipu, DisplayName: "Zhipu GLM", Gateway: PlatformGatewayOpenAI, CNProvider: true, LiteLLMProvider: "zhipu"},
+	{ID: PlatformDeepseek, DisplayName: "DeepSeek", Gateway: PlatformGatewayOpenAI, CNProvider: true, LiteLLMProvider: "deepseek"},
+	{ID: PlatformMiniMax, DisplayName: "MiniMax", Gateway: PlatformGatewayOpenAI, CNProvider: true, LiteLLMProvider: "minimax"},
+	{ID: PlatformOpenCodeGo, DisplayName: "OpenCode", Gateway: PlatformGatewayOpenAI, LiteLLMProvider: "opencode-go"},
+	{ID: PlatformTypeSafe, DisplayName: "TypeSafe / Jev", Gateway: PlatformGatewayAnthropic, LiteLLMProvider: "typesafe"},
+}
+
+var platformIndex = func() map[string]int {
+	index := make(map[string]int, len(platformList))
+	for i, spec := range platformList {
+		index[spec.ID] = i
+	}
+	return index
+}()
+
+// Platforms 返回全部具体平台（副本），按展示顺序。
+func Platforms() []PlatformSpec {
+	out := make([]PlatformSpec, len(platformList))
+	copy(out, platformList)
+	return out
+}
+
+// LookupPlatform 返回具体平台的登记信息；composite 与未知值返回 false。
+func LookupPlatform(id string) (PlatformSpec, bool) {
+	i, ok := platformIndex[id]
+	if !ok {
+		return PlatformSpec{}, false
+	}
+	return platformList[i], true
+}
+
+// IsConcretePlatform 报告 id 是否为已登记的具体平台（不含 composite）。
+func IsConcretePlatform(id string) bool {
+	_, ok := platformIndex[id]
+	return ok
+}
+
+// IsGroupPlatform 报告 id 是否可作为分组平台（具体平台或 composite）。
+func IsGroupPlatform(id string) bool {
+	return id == PlatformComposite || IsConcretePlatform(id)
+}
+
+// ConcretePlatformIDs 返回全部具体平台标识，按展示顺序。
+func ConcretePlatformIDs() []string {
+	return PlatformIDsWhere(func(PlatformSpec) bool { return true })
+}
+
+// PlatformIDsWhere 返回满足条件的具体平台标识，按展示顺序。
+func PlatformIDsWhere(match func(PlatformSpec) bool) []string {
+	out := make([]string, 0, len(platformList))
+	for _, spec := range platformList {
+		if match(spec) {
+			out = append(out, spec.ID)
+		}
+	}
+	return out
+}
+
+// compositePrecedenceHead 是组合分组查找顺序的固定前缀（历史顺序：Gemini 先于 OpenAI）。
+var compositePrecedenceHead = []string{PlatformAnthropic, PlatformGemini, PlatformOpenAI}
+
+// CompositePrecedencePlatformIDs 返回按平台依次回退时的顺序：组合分组在请求目标
+// 解析前逐平台查找定价 / 模型映射（先命中者生效）、拼接默认模型列表，以及调度快照
+// 遍历。沿用历史顺序 anthropic、gemini、openai，其余按展示顺序，新登记的平台追加在末尾。
+func CompositePrecedencePlatformIDs() []string {
+	out := make([]string, 0, len(platformList))
+	seen := make(map[string]struct{}, len(platformList))
+	for _, id := range compositePrecedenceHead {
+		if IsConcretePlatform(id) {
+			out = append(out, id)
+			seen[id] = struct{}{}
+		}
+	}
+	for _, spec := range platformList {
+		if _, ok := seen[spec.ID]; !ok {
+			out = append(out, spec.ID)
+		}
+	}
+	return out
+}
+
+// UsesOpenAIGateway 报告平台是否由 OpenAI 网关处理。
+func UsesOpenAIGateway(id string) bool {
+	spec, ok := LookupPlatform(id)
+	return ok && spec.Gateway == PlatformGatewayOpenAI
+}
+
+// IsCNProviderPlatform 报告平台是否为国产单一厂商。
+func IsCNProviderPlatform(id string) bool {
+	spec, ok := LookupPlatform(id)
+	return ok && spec.CNProvider
+}
diff --git a/backend/internal/domain/platforms_test.go b/backend/internal/domain/platforms_test.go
new file mode 100644
index 0000000000..327fc1c315
--- /dev/null
+++ b/backend/internal/domain/platforms_test.go
@@ -0,0 +1,67 @@
+package domain
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+// 重构前各处手写的平台列表，作为平台清单派生结果的等价基准。
+var (
+	legacyDisplayOrder = []string{
+		PlatformAnthropic, PlatformOpenAI, PlatformGemini, PlatformAntigravity, PlatformGrok,
+		PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe,
+	}
+	legacyCompositePrecedence = []string{
+		PlatformAnthropic, PlatformGemini, PlatformOpenAI, PlatformAntigravity, PlatformGrok,
+		PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe,
+	}
+	legacyOpenAIGateway = []string{
+		PlatformOpenAI, PlatformGrok, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo,
+	}
+	legacyCNProviders    = []string{PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax}
+	legacyLiteLLMByPlatf = map[string]string{
+		PlatformAnthropic: "anthropic", PlatformOpenAI: "openai", PlatformGemini: "gemini",
+		PlatformAntigravity: "anthropic", PlatformGrok: "xai", PlatformKimi: "moonshot",
+		PlatformZhipu: "zhipu", PlatformDeepseek: "deepseek", PlatformMiniMax: "minimax",
+		PlatformOpenCodeGo: "opencode-go", PlatformTypeSafe: "typesafe",
+	}
+)
+
+func TestPlatformListMatchesLegacyLists(t *testing.T) {
+	require.Equal(t, legacyDisplayOrder, ConcretePlatformIDs())
+	require.Equal(t, legacyCompositePrecedence, CompositePrecedencePlatformIDs())
+	require.Equal(t, legacyOpenAIGateway, PlatformIDsWhere(func(spec PlatformSpec) bool {
+		return spec.Gateway == PlatformGatewayOpenAI
+	}))
+	require.Equal(t, legacyCNProviders, PlatformIDsWhere(func(spec PlatformSpec) bool { return spec.CNProvider }))
+	for platform, provider := range legacyLiteLLMByPlatf {
+		spec, ok := LookupPlatform(platform)
+		require.True(t, ok, platform)
+		require.Equal(t, provider, spec.LiteLLMProvider, platform)
+	}
+}
+
+func TestPlatformListPredicates(t *testing.T) {
+	for _, platform := range legacyDisplayOrder {
+		require.True(t, IsConcretePlatform(platform), platform)
+		require.True(t, IsGroupPlatform(platform), platform)
+		spec, ok := LookupPlatform(platform)
+		require.True(t, ok, platform)
+		require.NotEmpty(t, spec.DisplayName, platform)
+		require.NotEmpty(t, spec.Gateway, platform)
+	}
+	require.False(t, IsConcretePlatform(PlatformComposite))
+	require.True(t, IsGroupPlatform(PlatformComposite))
+	for _, invalid := range []string{"", "moonshot", "Kimi", "openai ", "glm", "bogus"} {
+		require.False(t, IsConcretePlatform(invalid), invalid)
+		require.False(t, IsGroupPlatform(invalid), invalid)
+		require.False(t, UsesOpenAIGateway(invalid), invalid)
+	}
+}
+
+func TestPlatformsReturnsCopy(t *testing.T) {
+	platforms := Platforms()
+	platforms[0].ID = "mutated"
+	require.Equal(t, PlatformAnthropic, Platforms()[0].ID)
+}
diff --git a/backend/internal/handler/admin/channel_handler.go b/backend/internal/handler/admin/channel_handler.go
index 065aedb2f4..4d2aa03e15 100644
--- a/backend/internal/handler/admin/channel_handler.go
+++ b/backend/internal/handler/admin/channel_handler.go
@@ -5,6 +5,7 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/pagination"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/response"
@@ -631,20 +632,14 @@ func (h *ChannelHandler) GetModelDefaultPricing(c *gin.Context) {
 	})
 }
 
-// platformToLiteLLMProvider maps a channel platform name to the corresponding
-// LiteLLM provider string used as the key in the pricing catalog.
-var platformToLiteLLMProvider = map[string]string{
-	service.PlatformAnthropic:   "anthropic",
-	service.PlatformOpenAI:      "openai",
-	service.PlatformGemini:      "gemini",
-	service.PlatformAntigravity: "anthropic",
-	service.PlatformGrok:        "xai",
-	service.PlatformKimi:        "moonshot",
-	service.PlatformZhipu:       "zhipu",
-	service.PlatformDeepseek:    "deepseek",
-	service.PlatformMiniMax:     "minimax",
-	service.PlatformOpenCodeGo:  "opencode-go",
-	service.PlatformTypeSafe:    "typesafe",
+// platformLiteLLMProvider maps a channel platform name to the corresponding
+// LiteLLM provider string used as the key in the pricing catalog (platform list).
+func platformLiteLLMProvider(platform string) (string, bool) {
+	spec, ok := domain.LookupPlatform(platform)
+	if !ok || spec.LiteLLMProvider == "" {
+		return "", false
+	}
+	return spec.LiteLLMProvider, true
 }
 
 // SyncPricingModels 返回 LiteLLM 定价目录中指定平台的最新模型列表
@@ -657,7 +652,7 @@ func (h *ChannelHandler) SyncPricingModels(c *gin.Context) {
 		return
 	}
 
-	provider, ok := platformToLiteLLMProvider[platform]
+	provider, ok := platformLiteLLMProvider(platform)
 	if !ok {
 		response.ErrorFrom(c, infraerrors.BadRequest("UNSUPPORTED_PLATFORM",
 			fmt.Sprintf("unsupported platform: %s", platform)).
diff --git a/backend/internal/handler/admin/group_handler.go b/backend/internal/handler/admin/group_handler.go
index 774a00f882..e35ed66571 100644
--- a/backend/internal/handler/admin/group_handler.go
+++ b/backend/internal/handler/admin/group_handler.go
@@ -184,7 +184,7 @@ func sanitizeUpdateGroupRequestForSimpleMode(req *UpdateGroupRequest) {
 type CreateGroupRequest struct {
 	Name                      string                        `json:"name" binding:"required"`
 	Description               string                        `json:"description"`
-	Platform                  string                        `json:"platform" binding:"omitempty,oneof=anthropic openai gemini antigravity grok kimi zhipu deepseek minimax opencode_go typesafe composite"`
+	Platform                  string                        `json:"platform" binding:"omitempty,group_platform"`
 	RateMultiplier            float64                       `json:"rate_multiplier"`
 	IsExclusive               bool                          `json:"is_exclusive"`
 	SubscriptionType          string                        `json:"subscription_type" binding:"omitempty,oneof=standard subscription"`
@@ -258,7 +258,7 @@ type CreateGroupRequest struct {
 type UpdateGroupRequest struct {
 	Name                      string                         `json:"name"`
 	Description               *string                        `json:"description"`
-	Platform                  string                         `json:"platform" binding:"omitempty,oneof=anthropic openai gemini antigravity grok kimi zhipu deepseek minimax opencode_go typesafe composite"`
+	Platform                  string                         `json:"platform" binding:"omitempty,group_platform"`
 	RateMultiplier            *float64                       `json:"rate_multiplier"`
 	IsExclusive               *bool                          `json:"is_exclusive"`
 	Status                    string                         `json:"status" binding:"omitempty,oneof=active inactive"`
@@ -332,7 +332,7 @@ type UpdateGroupRequest struct {
 type CompositeRouteRequest struct {
 	PublicModel    string `json:"public_model" binding:"required"`
 	MatchType      string `json:"match_type" binding:"omitempty,oneof=exact prefix"`
-	TargetPlatform string `json:"target_platform" binding:"required,oneof=anthropic openai gemini antigravity grok kimi zhipu deepseek minimax opencode_go typesafe"`
+	TargetPlatform string `json:"target_platform" binding:"required,concrete_platform"`
 	UpstreamModel  string `json:"upstream_model"`
 	Endpoint       string `json:"endpoint" binding:"omitempty,oneof=any messages count_tokens responses chat_completions embeddings images gemini"`
 	Priority       int    `json:"priority"`
diff --git a/backend/internal/handler/admin/platform_validation.go b/backend/internal/handler/admin/platform_validation.go
new file mode 100644
index 0000000000..7eff99b88d
--- /dev/null
+++ b/backend/internal/handler/admin/platform_validation.go
@@ -0,0 +1,24 @@
+package admin
+
+import (
+	"github.com/Wei-Shaw/sub2api/internal/domain"
+	"github.com/gin-gonic/gin/binding"
+	"github.com/go-playground/validator/v10"
+)
+
+// 平台相关的请求绑定校验标签，由平台清单（domain/platforms.go）驱动，替代在
+// binding 标签里手写 oneof 白名单（新增平台时易漏加，导致分组无法创建）：
+//   - group_platform：已登记的具体平台或 composite；
+//   - concrete_platform：已登记的具体平台。
+func init() {
+	engine, ok := binding.Validator.Engine().(*validator.Validate)
+	if !ok {
+		return
+	}
+	_ = engine.RegisterValidation("group_platform", func(fl validator.FieldLevel) bool {
+		return domain.IsGroupPlatform(fl.Field().String())
+	})
+	_ = engine.RegisterValidation("concrete_platform", func(fl validator.FieldLevel) bool {
+		return domain.IsConcretePlatform(fl.Field().String())
+	})
+}
diff --git a/backend/internal/handler/gateway_handler.go b/backend/internal/handler/gateway_handler.go
index beb9400d11..0b58876d8d 100644
--- a/backend/internal/handler/gateway_handler.go
+++ b/backend/internal/handler/gateway_handler.go
@@ -1301,7 +1301,7 @@ func (h *GatewayHandler) compositeAvailableModels(ctx context.Context, groupID *
 	seen := make(map[string]struct{})
 	models := make([]string, 0)
 	schedulablePlatforms := h.gatewayService.GetSchedulablePlatforms(ctx, groupID)
-	for _, platform := range []string{service.PlatformAnthropic, service.PlatformGemini, service.PlatformOpenAI, service.PlatformAntigravity, service.PlatformGrok, service.PlatformKimi, service.PlatformZhipu, service.PlatformDeepseek, service.PlatformMiniMax, service.PlatformOpenCodeGo, service.PlatformTypeSafe} {
+	for _, platform := range domain.CompositePrecedencePlatformIDs() {
 		if platform == service.PlatformTypeSafe && !includeSystemOne {
 			continue
 		}
@@ -1503,10 +1503,13 @@ func defaultModelIDsForPlatform(platform string) []string {
 	case service.PlatformComposite:
 		ids := make([]string, 0)
 		seen := make(map[string]struct{})
-		// TypeSafe is deliberately absent: jev-latest only works through
-		// /v1/systemone, so the static fallback never advertises it to LLM
-		// clients. compositeAvailableModels lists it when the group can serve it.
-		for _, concretePlatform := range []string{service.PlatformAnthropic, service.PlatformGemini, service.PlatformOpenAI, service.PlatformAntigravity, service.PlatformGrok, service.PlatformKimi, service.PlatformZhipu, service.PlatformDeepseek, service.PlatformMiniMax, service.PlatformOpenCodeGo} {
+		for _, concretePlatform := range domain.CompositePrecedencePlatformIDs() {
+			// TypeSafe is deliberately skipped: jev-latest only works through
+			// /v1/systemone, so the static fallback never advertises it to LLM
+			// clients. compositeAvailableModels lists it when the group can serve it.
+			if concretePlatform == service.PlatformTypeSafe {
+				continue
+			}
 			for _, id := range defaultModelIDsForPlatform(concretePlatform) {
 				if _, ok := seen[id]; ok {
 					continue
diff --git a/backend/internal/handler/openai_gateway_handler.go b/backend/internal/handler/openai_gateway_handler.go
index 21f0cace70..65d002e54b 100644
--- a/backend/internal/handler/openai_gateway_handler.go
+++ b/backend/internal/handler/openai_gateway_handler.go
@@ -17,6 +17,7 @@ import (
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/ip"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/logger"
@@ -330,9 +331,9 @@ func allowOpenAICompatibleMessagesDispatch(c *gin.Context, apiKey *service.APIKe
 
 func openAICompatibleTextTargetAllowed(c *gin.Context, apiKey *service.APIKey, model string) bool {
 	return compositeTargetPlatformAllowed(c, apiKey, model,
-		service.PlatformOpenAI, service.PlatformGrok,
-		service.PlatformKimi, service.PlatformZhipu, service.PlatformDeepseek,
-		service.PlatformMiniMax, service.PlatformOpenCodeGo)
+		domain.PlatformIDsWhere(func(spec domain.PlatformSpec) bool {
+			return spec.Gateway == domain.PlatformGatewayOpenAI
+		})...)
 }
 
 // isResponsesWebSocketCompositePlatform 限定 composite 分组在 Responses WebSocket
diff --git a/backend/internal/model/error_passthrough_rule.go b/backend/internal/model/error_passthrough_rule.go
index da928125f2..c4ca164dc0 100644
--- a/backend/internal/model/error_passthrough_rule.go
+++ b/backend/internal/model/error_passthrough_rule.go
@@ -49,21 +49,9 @@ const (
 	PlatformTypeSafe    = domain.PlatformTypeSafe
 )
 
-// AllPlatforms 返回所有支持的平台列表
+// AllPlatforms 返回所有支持的平台列表（平台清单，按展示顺序）。
 func AllPlatforms() []string {
-	return []string{
-		PlatformAnthropic,
-		PlatformOpenAI,
-		PlatformGemini,
-		PlatformAntigravity,
-		PlatformGrok,
-		PlatformKimi,
-		PlatformZhipu,
-		PlatformDeepseek,
-		PlatformMiniMax,
-		PlatformOpenCodeGo,
-		PlatformTypeSafe,
-	}
+	return domain.ConcretePlatformIDs()
 }
 
 // Validate 验证规则配置的有效性
diff --git a/backend/internal/server/routes/gateway.go b/backend/internal/server/routes/gateway.go
index 870ae14c5c..a921a42d44 100644
--- a/backend/internal/server/routes/gateway.go
+++ b/backend/internal/server/routes/gateway.go
@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	"github.com/Wei-Shaw/sub2api/internal/handler"
 	pkghttputil "github.com/Wei-Shaw/sub2api/internal/pkg/httputil"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/requestmodel"
@@ -46,22 +47,15 @@ func RegisterGatewayRoutes(
 	groupModelAllowlist := middleware.GroupModelAllowlist()
 
 	isOpenAIResponsesCompatibleGatewayPlatform := func(c *gin.Context) bool {
-		switch getGroupPlatform(c) {
-		case service.PlatformOpenAI, service.PlatformGrok,
-			service.PlatformKimi, service.PlatformZhipu, service.PlatformDeepseek,
-			service.PlatformMiniMax, service.PlatformOpenCodeGo:
-			// 国产 OpenAI 兼容供应商与 openai/grok 一样经 OpenAI 网关转发。
-			return true
-		default:
-			return false
-		}
+		// openai、grok 与多协议 API Key 供应商经 OpenAI 网关转发（平台清单）。
+		return domain.UsesOpenAIGateway(getGroupPlatform(c))
 	}
 	countTokensHandler := func(c *gin.Context) {
-		switch getGroupPlatform(c) {
-		case service.PlatformOpenAI, service.PlatformKimi, service.PlatformZhipu, service.PlatformDeepseek, service.PlatformMiniMax, service.PlatformOpenCodeGo:
-			h.OpenAIGateway.CountTokens(c)
-		case service.PlatformGrok:
+		switch platform := getGroupPlatform(c); {
+		case platform == service.PlatformGrok:
 			h.OpenAIGateway.GrokCountTokens(c)
+		case domain.UsesOpenAIGateway(platform):
+			h.OpenAIGateway.CountTokens(c)
 		default:
 			h.Gateway.CountTokens(c)
 		}
diff --git a/backend/internal/service/account.go b/backend/internal/service/account.go
index 97a797580c..04b609e9e5 100644
--- a/backend/internal/service/account.go
+++ b/backend/internal/service/account.go
@@ -303,7 +303,7 @@ func (a *Account) IsCNProvider() bool {
 // openai/grok 原生走 OpenAI 网关；国产供应商同为 OpenAI Chat Completions
 // 兼容上游，也经 OpenAI 网关转发。OpenCode 同样经 OpenAI 网关按模型分流。
 func (a *Account) IsOpenAICompatible() bool {
-	return a != nil && (a.Platform == PlatformOpenAI || a.Platform == PlatformGrok || a.IsCNProvider() || a.IsOpenCodeGo())
+	return a != nil && domain.UsesOpenAIGateway(a.Platform)
 }
 
 func (a *Account) GeminiOAuthType() string {
@@ -1384,7 +1384,7 @@ func (a *Account) IsOpenAIApiKey() bool {
 // 适用 openai、国产 OpenAI 兼容供应商（kimi/zhipu/deepseek）与 OpenCode Go；
 // grok 走 GetGrokBaseURL，此处对 grok 返回 "" 以保持原有行为。
 func (a *Account) GetOpenAIBaseURL() string {
-	if !a.IsOpenAI() && !a.IsCNProvider() && !a.IsOpenCodeGo() {
+	if !a.IsOpenAI() && !a.IsMultiProtocolAPIKey() {
 		return ""
 	}
 	if a.IsMultiProtocolAPIKey() && a.IsAdaptiveAPIProtocol() {
diff --git a/backend/internal/service/account_header_override.go b/backend/internal/service/account_header_override.go
index 7f05e253ac..e807cac15d 100644
--- a/backend/internal/service/account_header_override.go
+++ b/backend/internal/service/account_header_override.go
@@ -77,10 +77,10 @@ func (a *Account) IsHeaderOverrideEligible() bool {
 	if a == nil {
 		return false
 	}
-	switch a.Platform {
-	case PlatformAnthropic, PlatformOpenAI, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo:
+	switch {
+	case a.Platform == PlatformAnthropic, a.Platform == PlatformOpenAI, IsMultiProtocolAPIKeyProvider(a.Platform):
 		return a.Type == AccountTypeAPIKey
-	case PlatformGrok:
+	case a.Platform == PlatformGrok:
 		return a.Type == AccountTypeAPIKey || a.Type == AccountTypeOAuth
 	default:
 		return false
diff --git a/backend/internal/service/account_service.go b/backend/internal/service/account_service.go
index bbf668eaff..7980a5c447 100644
--- a/backend/internal/service/account_service.go
+++ b/backend/internal/service/account_service.go
@@ -522,10 +522,12 @@ func (s *AccountService) TestCredentials(ctx context.Context, id int64) error {
 	case PlatformTypeSafe:
 		// TypeSafe credentials are API keys; inference failures drive health and cooldown state.
 		return nil
-	case PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo:
-		// 国产 OpenAI 兼容供应商与 OpenCode：凭证为 API Key，实际可用性经余额/额度探测与转发路径验证。
-		return nil
 	default:
+		if IsMultiProtocolAPIKeyProvider(account.Platform) {
+			// 多协议 API Key 供应商（国产厂商与聚合平台）：凭证为 API Key，实际可用性
+			// 经余额/额度探测与转发路径验证。
+			return nil
+		}
 		return fmt.Errorf("unsupported platform: %s", account.Platform)
 	}
 }
diff --git a/backend/internal/service/admin_group.go b/backend/internal/service/admin_group.go
index 103c9edc25..41d16bb6c9 100644
--- a/backend/internal/service/admin_group.go
+++ b/backend/internal/service/admin_group.go
@@ -10,6 +10,7 @@ import (
 
 	dbent "github.com/Wei-Shaw/sub2api/ent"
 	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/antigravity"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/claude"
 	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
@@ -319,10 +320,13 @@ func defaultAllowImageGenerationForPlatform(platform string) bool {
 func compositeDefaultModelsListCandidateIDs() []string {
 	seen := make(map[string]struct{})
 	ids := make([]string, 0)
-	// TypeSafe stays out of the static composite candidates (jev-latest only works
-	// through /v1/systemone); groups with TypeSafe accounts still get it from the
-	// account model mappings collected by GetGroupModelsListCandidates.
-	for _, platform := range []string{PlatformAnthropic, PlatformGemini, PlatformOpenAI, PlatformAntigravity, PlatformGrok, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo} {
+	for _, platform := range domain.CompositePrecedencePlatformIDs() {
+		// TypeSafe stays out of the static composite candidates (jev-latest only works
+		// through /v1/systemone); groups with TypeSafe accounts still get it from the
+		// account model mappings collected by GetGroupModelsListCandidates.
+		if platform == PlatformTypeSafe {
+			continue
+		}
 		for _, id := range defaultModelsListCandidateIDs(platform) {
 			if _, ok := seen[id]; ok {
 				continue
diff --git a/backend/internal/service/channel_service.go b/backend/internal/service/channel_service.go
index b2c605cd80..85d6409301 100644
--- a/backend/internal/service/channel_service.go
+++ b/backend/internal/service/channel_service.go
@@ -9,6 +9,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
 	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/pagination"
@@ -368,7 +369,7 @@ func isPlatformPricingMatch(groupPlatform, pricingPlatform string) bool {
 // fallback used before a request target has been resolved.
 func matchingPlatforms(groupPlatform string) []string {
 	if groupPlatform == PlatformComposite {
-		return []string{PlatformAnthropic, PlatformGemini, PlatformOpenAI, PlatformAntigravity, PlatformGrok, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe}
+		return domain.CompositePrecedencePlatformIDs()
 	}
 	return []string{groupPlatform}
 }
diff --git a/backend/internal/service/composite_platform.go b/backend/internal/service/composite_platform.go
index c10e335cbe..b7fcfd3451 100644
--- a/backend/internal/service/composite_platform.go
+++ b/backend/internal/service/composite_platform.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"strings"
 
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
 )
 
@@ -204,11 +205,5 @@ func (s *GatewayService) resolveCompositeRouteDecision(ctx context.Context, grou
 }
 
 func isConcreteRequestPlatform(platform string) bool {
-	switch platform {
-	case PlatformAnthropic, PlatformOpenAI, PlatformGemini, PlatformAntigravity, PlatformGrok,
-		PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe:
-		return true
-	default:
-		return false
-	}
+	return domain.IsConcretePlatform(platform)
 }
diff --git a/backend/internal/service/domain_constants.go b/backend/internal/service/domain_constants.go
index 014e6f6bb9..c6fc312753 100644
--- a/backend/internal/service/domain_constants.go
+++ b/backend/internal/service/domain_constants.go
@@ -101,14 +101,10 @@ const (
 	DefaultOpenCodeZenAnthropicBaseURL = "https://opencode.ai/zen"
 )
 
-// IsCNProvider 报告 platform 是否为国产 OpenAI 兼容供应商（kimi/zhipu/deepseek/minimax）。
+// IsCNProvider 报告 platform 是否为国产 OpenAI 兼容供应商（kimi/zhipu/deepseek/minimax），
+// 以平台清单（domain/platforms.go）为准。
 func IsCNProvider(platform string) bool {
-	switch platform {
-	case PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax:
-		return true
-	default:
-		return false
-	}
+	return domain.IsCNProviderPlatform(platform)
 }
 
 // IsOpenCodeGo 报告 platform 是否为 OpenCode Go 订阅网关。
@@ -123,22 +119,9 @@ func IsMultiProtocolAPIKeyProvider(platform string) bool {
 	return LookupProviderProfile(platform) != nil
 }
 
-// AllowedQuotaPlatforms 是允许设置 user × platform quota 的平台列表（单一权威来源）。
-// ent/schema/user_platform_quota.go 的 Validate 函数独立维护（构建期约束），
-// 若新增平台需同步修改该 schema。
-var AllowedQuotaPlatforms = []string{
-	PlatformAnthropic,
-	PlatformOpenAI,
-	PlatformGemini,
-	PlatformAntigravity,
-	PlatformGrok,
-	PlatformKimi,
-	PlatformZhipu,
-	PlatformDeepseek,
-	PlatformMiniMax,
-	PlatformOpenCodeGo,
-	PlatformTypeSafe,
-}
+// AllowedQuotaPlatforms 是允许设置 user × platform quota 的平台列表：全部已登记的
+// 具体平台（domain/platforms.go），ent/schema/user_platform_quota.go 的校验同源。
+var AllowedQuotaPlatforms = domain.ConcretePlatformIDs()
 
 // AllowedSchedulingThresholdPlatforms 是允许设置账号自动停调阈值的平台列表。
 // openai/anthropic/grok 有原生用量窗口；kimi/zhipu/minimax 的 Coding Plan 同样暴露
diff --git a/backend/internal/service/openai_gateway_scheduling.go b/backend/internal/service/openai_gateway_scheduling.go
index fe93880ee0..04fc18bb94 100644
--- a/backend/internal/service/openai_gateway_scheduling.go
+++ b/backend/internal/service/openai_gateway_scheduling.go
@@ -14,6 +14,7 @@ import (
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/openai"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/xai"
 	"github.com/gin-gonic/gin"
@@ -285,18 +286,16 @@ func (s *OpenAIGatewayService) SelectAccountForTokenCount(
 	)
 }
 
-// NormalizeOpenAICompatiblePlatform 保留 grok 与国产 OpenAI 兼容供应商（kimi/zhipu/
-// deepseek）的原值，其他值一律归一为 openai。调度器据此对账号与请求做精确平台匹配：
+// NormalizeOpenAICompatiblePlatform 保留走 OpenAI 网关的平台（openai、grok 与多协议
+// API Key 供应商，见平台清单）的原值，其他值一律归一为 openai。调度器据此对账号与请求做精确平台匹配：
 // kimi 分组请求只命中 kimi 账号，语义与 openai/grok 一致。
 // （upstream 曾将本函数改为未导出 normalizeOpenAICompatiblePlatform，本分支的
 // handler 调度入口仍需导出，保持导出名。）
 func NormalizeOpenAICompatiblePlatform(platform string) string {
-	switch platform {
-	case PlatformGrok, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo:
+	if domain.UsesOpenAIGateway(platform) {
 		return platform
-	default:
-		return PlatformOpenAI
 	}
+	return PlatformOpenAI
 }
 
 // noAvailableOpenAISelectionError builds the standard "no account available" error
diff --git a/backend/internal/service/platform_list_test.go b/backend/internal/service/platform_list_test.go
new file mode 100644
index 0000000000..09cc70b090
--- /dev/null
+++ b/backend/internal/service/platform_list_test.go
@@ -0,0 +1,118 @@
+//go:build unit
+
+package service
+
+import (
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/domain"
+	"github.com/stretchr/testify/require"
+)
+
+// 以下为重构前各处手写的平台列表 / switch，作为平台清单派生结果的等价基准。
+var (
+	legacyAllPlatforms = []string{
+		PlatformAnthropic, PlatformOpenAI, PlatformGemini, PlatformAntigravity, PlatformGrok,
+		PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe,
+	}
+	legacySchedulerSnapshotPlatforms = []string{
+		PlatformAnthropic, PlatformGemini, PlatformOpenAI, PlatformAntigravity, PlatformGrok,
+		PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe,
+	}
+	legacyCompositeMatchingPlatforms = legacySchedulerSnapshotPlatforms
+	legacyMultiProtocolProviders     = []string{PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo}
+	platformProbeValues              = append(append([]string{}, legacyAllPlatforms...), PlatformComposite, "", "moonshot", "Kimi", "openai ", "glm", "bogus")
+	platformProbeAccountTypes        = []string{AccountTypeAPIKey, AccountTypeOAuth, AccountTypeSetupToken, AccountTypeUpstream, ""}
+)
+
+func legacyIsCNProvider(platform string) bool {
+	switch platform {
+	case PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax:
+		return true
+	}
+	return false
+}
+
+func legacyIsOpenAICompatible(platform string) bool {
+	return platform == PlatformOpenAI || platform == PlatformGrok || legacyIsCNProvider(platform) || platform == PlatformOpenCodeGo
+}
+
+func legacyNormalizeOpenAICompatiblePlatform(platform string) string {
+	switch platform {
+	case PlatformGrok, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo:
+		return platform
+	}
+	return PlatformOpenAI
+}
+
+func legacyIsUpstreamBillingProbeIdentity(platform, accountType string) bool {
+	if accountType != AccountTypeAPIKey {
+		return false
+	}
+	switch platform {
+	case PlatformOpenAI, PlatformAnthropic, PlatformGemini, PlatformAntigravity, PlatformGrok,
+		PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo,
+		PlatformTypeSafe:
+		return true
+	}
+	return false
+}
+
+func legacyIsHeaderOverrideEligible(platform, accountType string) bool {
+	switch platform {
+	case PlatformAnthropic, PlatformOpenAI, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo:
+		return accountType == AccountTypeAPIKey
+	case PlatformGrok:
+		return accountType == AccountTypeAPIKey || accountType == AccountTypeOAuth
+	}
+	return false
+}
+
+func legacyIsConcreteRequestPlatform(platform string) bool {
+	for _, p := range legacyAllPlatforms {
+		if p == platform {
+			return true
+		}
+	}
+	return false
+}
+
+func TestPlatformListDerivedListsMatchLegacy(t *testing.T) {
+	require.Equal(t, legacyAllPlatforms, AllowedQuotaPlatforms)
+	require.Equal(t, legacySchedulerSnapshotPlatforms, schedulerSnapshotPlatforms())
+	require.Equal(t, legacyCompositeMatchingPlatforms, matchingPlatforms(PlatformComposite))
+	require.Equal(t, []string{PlatformKimi}, matchingPlatforms(PlatformKimi))
+
+	var multiProtocol []string
+	for _, platform := range legacyAllPlatforms {
+		if IsMultiProtocolAPIKeyProvider(platform) {
+			multiProtocol = append(multiProtocol, platform)
+		}
+	}
+	require.Equal(t, legacyMultiProtocolProviders, multiProtocol)
+}
+
+func TestPlatformListDerivedPredicatesMatchLegacy(t *testing.T) {
+	for _, platform := range platformProbeValues {
+		require.Equal(t, legacyIsCNProvider(platform), IsCNProvider(platform), platform)
+		require.Equal(t, legacyIsConcreteRequestPlatform(platform), isConcreteRequestPlatform(platform), platform)
+		require.Equal(t, legacyNormalizeOpenAICompatiblePlatform(platform), NormalizeOpenAICompatiblePlatform(platform), platform)
+		require.Equal(t, legacyIsOpenAICompatible(platform), (&Account{Platform: platform}).IsOpenAICompatible(), platform)
+		for _, accountType := range platformProbeAccountTypes {
+			require.Equal(t, legacyIsUpstreamBillingProbeIdentity(platform, accountType),
+				IsUpstreamBillingProbeIdentity(platform, accountType), "%s/%s", platform, accountType)
+			require.Equal(t, legacyIsHeaderOverrideEligible(platform, accountType),
+				(&Account{Platform: platform, Type: accountType}).IsHeaderOverrideEligible(), "%s/%s", platform, accountType)
+		}
+	}
+}
+
+// 多协议 API Key 供应商经 OpenAI 网关转发（NormalizeOpenAICompatiblePlatform、
+// countTokens 路由等依赖此约束），ProviderProfile 登记的平台必须在平台清单中声明 openai 网关。
+func TestProviderProfilesUseOpenAIGateway(t *testing.T) {
+	for platform := range providerProfiles {
+		spec, ok := domain.LookupPlatform(platform)
+		require.True(t, ok, platform)
+		require.Equal(t, domain.PlatformGatewayOpenAI, spec.Gateway, platform)
+	}
+}
diff --git a/backend/internal/service/scheduler_snapshot_service.go b/backend/internal/service/scheduler_snapshot_service.go
index 6f999c189c..2073ad0f53 100644
--- a/backend/internal/service/scheduler_snapshot_service.go
+++ b/backend/internal/service/scheduler_snapshot_service.go
@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/logger"
 )
 
@@ -608,10 +609,10 @@ func (s *SchedulerSnapshotService) handleBulkAccountEvent(ctx context.Context, p
 			continue
 		}
 		accountGroupIDs := s.normalizeGroupIDs(account.GroupIDs)
-		switch account.Platform {
-		case PlatformAnthropic, PlatformGemini, PlatformOpenAI, PlatformGrok, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe:
+		switch {
+		case account.Platform != PlatformAntigravity && isConcreteRequestPlatform(account.Platform):
 			addPlatformGroups(account.Platform, accountGroupIDs)
-		case PlatformAntigravity:
+		case account.Platform == PlatformAntigravity:
 			// 批量更新可能刚关闭 mixed_scheduling，仍需清理两个兼容平台的旧快照。
 			addPlatformGroups(PlatformAntigravity, accountGroupIDs)
 			addPlatformGroups(PlatformAnthropic, accountGroupIDs)
@@ -824,8 +825,9 @@ func (s *SchedulerSnapshotService) rebuildByAccount(ctx context.Context, account
 	return s.rebuildBuckets(ctx, buckets, reason)
 }
 
-func schedulerSnapshotPlatforms() [11]string {
-	return [11]string{PlatformAnthropic, PlatformGemini, PlatformOpenAI, PlatformAntigravity, PlatformGrok, PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo, PlatformTypeSafe}
+// schedulerSnapshotPlatforms 返回需要维护调度快照的全部具体平台（平台清单）。
+func schedulerSnapshotPlatforms() []string {
+	return domain.CompositePrecedencePlatformIDs()
 }
 
 // 生命周期辅助函数有意排除 group0；full rebuild 构造 group0 canonical 集时必须显式调用 canonical helper。
diff --git a/backend/internal/service/upstream_billing_probe.go b/backend/internal/service/upstream_billing_probe.go
index b34900f4f5..a53fca5597 100644
--- a/backend/internal/service/upstream_billing_probe.go
+++ b/backend/internal/service/upstream_billing_probe.go
@@ -19,6 +19,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/Wei-Shaw/sub2api/internal/domain"
 	infraerrors "github.com/Wei-Shaw/sub2api/internal/pkg/errors"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/logger"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/tlsfingerprint"
@@ -1008,17 +1009,7 @@ func decodeUpstreamBillingProbeSnapshot(extra map[string]any) *UpstreamBillingPr
 // type=apikey by the admin form, so only pre-existing type=upstream rows
 // cannot turn the probe on.
 func IsUpstreamBillingProbeIdentity(platform, accountType string) bool {
-	if accountType != AccountTypeAPIKey {
-		return false
-	}
-	switch platform {
-	case PlatformOpenAI, PlatformAnthropic, PlatformGemini, PlatformAntigravity, PlatformGrok,
-		PlatformKimi, PlatformZhipu, PlatformDeepseek, PlatformMiniMax, PlatformOpenCodeGo,
-		PlatformTypeSafe:
-		return true
-	default:
-		return false
-	}
+	return accountType == AccountTypeAPIKey && domain.IsConcretePlatform(platform)
 }
 
 func isUpstreamBillingProbeAccount(account *Account) bool {