diff --git a/internal/services/gateway/admin_write_iot_automations.go b/internal/services/gateway/admin_write_iot_automations.go
index fb96732..0ac79fe 100644
--- a/internal/services/gateway/admin_write_iot_automations.go
+++ b/internal/services/gateway/admin_write_iot_automations.go
@@ -104,7 +104,7 @@ func mapIotError(err error) *apperr.AppError {
 // automationCreateRequest 是 POST /api/v1/admin/automations 的请求体。
 type automationCreateRequest struct {
 	Name       string `json:"name"`
-	Kind       string `json:"kind"` // cron | event
+	Kind       string `json:"kind"` // 取值：cron | event
 	Expression string `json:"expression"`
 }
 
diff --git a/internal/services/gateway/history.go b/internal/services/gateway/history.go
index cbbdcae..56a8b65 100644
--- a/internal/services/gateway/history.go
+++ b/internal/services/gateway/history.go
@@ -17,7 +17,7 @@ import (
 // （main 或 sub）的线上结构。
 type historySessionSummary struct {
 	ID        string `json:"id"`
-	Type      string `json:"type"` // "main" | "sub"
+	Type      string `json:"type"` // 取值："main" | "sub"
 	Title     string `json:"title,omitempty"`
 	CreatedAt int64  `json:"createdAt"`
 	// Pinned 把会话浮到列表顶部（D5）。它只是排序元数据，
@@ -44,7 +44,7 @@ type historySessionSummary struct {
 
 // historyLastMessage 是会话摘要中最后消息预览的线上结构。
 type historyLastMessage struct {
-	Role      string `json:"role"` // "user" | "assistant"
+	Role      string `json:"role"` // 取值："user" | "assistant"
 	Content   string `json:"content"`
 	CreatedAt int64  `json:"createdAt"`
 }