diff --git a/server/internal/handler/email_auth.go b/server/internal/handler/email_auth.go
index 6286a93..bbc5402 100644
--- a/server/internal/handler/email_auth.go
+++ b/server/internal/handler/email_auth.go
@@ -2,6 +2,7 @@ package handler
 
 import (
 	"errors"
+	"log"
 	"net/http"
 
 	"github.com/gin-gonic/gin"
@@ -26,6 +27,8 @@ func RequestEmailLoginCode(c *gin.Context) {
 		return
 	}
 	if err != nil {
+		// 保留 service 返回的 provider 错误（含服务商名称与上游状态码），便于生产排障关联
+		log.Printf("[EMAIL-AUTH] 验证码发送失败: email=%s err=%v", request.Email, err)
 		c.JSON(http.StatusServiceUnavailable, gin.H{"code": 503, "msg": "验证码暂时无法发送"})
 		return
 	}