diff --git a/src/dhapi/router/credentials_provider.py b/src/dhapi/router/credentials_provider.py
index d68845c..59a843d 100644
--- a/src/dhapi/router/credentials_provider.py
+++ b/src/dhapi/router/credentials_provider.py
@@ -7,17 +7,9 @@
 logger = logging.getLogger(__name__)
 
 
-def read_credentials_file(profile_name):
-    with open(os.path.expanduser("~/.dhapi/credentials"), "r", encoding="UTF-8") as f:
-        file = f.read()
-    config = tomli.loads(file)
-    credentials = config.get(profile_name)
-    return credentials
-
-
 def get_credentials(profile_name):
     try:
-        credentials = read_credentials_file(profile_name)
+        credentials = _read_credentials_file(profile_name)
     except FileNotFoundError:
         print("❌ ~/.dhapi/credentials 파일을 찾을 수 없습니다. 파일을 생성하고 프로필을 추가하시겠습니까? [Y/n] ", end="")
         answer = input().strip().lower()
@@ -25,29 +17,37 @@ def get_credentials(profile_name):
             print("📝 입력된 프로필 이름을 사용하시겠습니까? [Y/n]", end="")
             answer = input().strip().lower()
             if answer in ["y", "yes", ""]:
-                add_credentials(profile_name)
+                _add_credentials(profile_name)
             else:
                 print("📝 프로필 이름을 입력하세요: ", end="")
                 profile_name = input().strip()
-                add_credentials(profile_name)
+                _add_credentials(profile_name)
         else:
             raise FileNotFoundError("~/.dhapi/credentials 파일을 찾을 수 없습니다.")
 
-    credentials = read_credentials_file(profile_name)
+    credentials = _read_credentials_file(profile_name)
 
     if credentials is None:
         print(f"❌'{profile_name}' 프로필을 찾지 못했습니다. 추가하시겠습니까? [Y/n] ", end="")
         answer = input().strip().lower()
         if answer in ["y", "yes", ""]:
-            add_credentials(profile_name)
-            credentials = read_credentials_file(profile_name)
+            _add_credentials(profile_name)
+            credentials = _read_credentials_file(profile_name)
             return credentials
         raise ValueError(f"~/.dhapi/credentials 파일에서 '{profile_name}' 프로필을 찾지 못했습니다.")
 
     return credentials
 
 
-def add_credentials(profile_name):
+def _read_credentials_file(profile_name):
+    with open(os.path.expanduser("~/.dhapi/credentials"), "r", encoding="UTF-8") as f:
+        file = f.read()
+    config = tomli.loads(file)
+    credentials = config.get(profile_name)
+    return credentials
+
+
+def _add_credentials(profile_name):
     print("📝 사용자 ID를 입력하세요: ", end="")
     user_id = input().strip()
     print("📝 사용자 비밀번호를 입력하세요: ", end="")