diff --git a/server/PacketHandler.cpp b/server/PacketHandler.cpp
index 986359e..dd2456a 100644
--- a/server/PacketHandler.cpp
+++ b/server/PacketHandler.cpp
@@ -52,9 +52,9 @@ PacketHandler::HandlePacket(std::shared_ptr<Session> session,
   } break;
 
   case PacketID::CS_UpgradeSword: {
-    auto currentLevel = session->GetSwordLevel();
-    auto cost = SwordLogic::GetUpgradeCost(currentLevel);
-    auto currentGold = session->GetGold();
+    uint32_t currentLevel = session->GetSwordLevel();
+    uint64_t cost = SwordLogic::GetUpgradeCost(currentLevel);
+    uint64_t currentGold = session->GetGold();
 
     Protocol::SC_UpgradeResult res;
     if (currentGold < cost) {
@@ -62,7 +62,7 @@ PacketHandler::HandlePacket(std::shared_ptr<Session> session,
       res.set_result(2);
     } else {
       session->SetGold(currentGold - cost);
-      auto result = SwordLogic::TryUpgrade(currentLevel);
+      uint8_t result = SwordLogic::TryUpgrade(currentLevel);
       res.set_result(result);
 
       // 성공
@@ -113,9 +113,9 @@ PacketHandler::HandlePacket(std::shared_ptr<Session> session,
   } break;
 
   case PacketID::CS_SellSword: {
-    auto currentLevel = session->GetSwordLevel();
-    auto price = SwordLogic::GetSellPrice(currentLevel);
-    auto newGold = session->GetGold() + price;
+    uint32_t currentLevel = session->GetSwordLevel();
+    uint64_t price = SwordLogic::GetSellPrice(currentLevel);
+    uint64_t newGold = session->GetGold() + price;
 
     session->SetGold(newGold);
     session->SetSwordLevel(0);
diff --git a/server/SessionManager.cpp b/server/SessionManager.cpp
index 6120e67..35c19ba 100644
--- a/server/SessionManager.cpp
+++ b/server/SessionManager.cpp
@@ -43,6 +43,8 @@ void SessionManager::Broadcast(PacketHeader header,
   std::memcpy(buffer.data() + sizeof(PacketHeader), body.data(), body.size());
 
   for (auto &session : sessions_) {
+    // session::send에 span을 전달해야 함. 벡터 자체를 전달할 수도 있지만 우리
+    // Send는 span을 인자로 받음. Session::Send는 span을 받아 복사본을 생성함.
     session->Send(buffer);
   }
 }