diff --git a/a2a/slack_researcher/slack_researcher/config.py b/a2a/slack_researcher/slack_researcher/config.py
index f2f562e1..397bf991 100644
--- a/a2a/slack_researcher/slack_researcher/config.py
+++ b/a2a/slack_researcher/slack_researcher/config.py
@@ -9,6 +9,9 @@
 
 
 class Settings(BaseSettings):
+    # static path for client secret file
+    secret_file_path: str = "/shared/secret.txt"
+
     LOG_LEVEL: Literal['DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL'] = Field(
         os.getenv("LOG_LEVEL", "DEBUG"),
         description="Application log level",       
@@ -60,7 +63,7 @@ class Settings(BaseSettings):
         description="Client ID to authenticate to OAuth server"
     )
     CLIENT_SECRET: Optional[str] = Field(
-        os.getenv("CLIENT_SECRET", None),
+        None,
         description="Client secret to authenticate to OAuth server"
     )
     TARGET_AUDIENCE: Optional[str] = Field(
@@ -84,6 +87,15 @@ def validate_extra_headers(self) -> "Settings":
             except json.JSONDecodeError:
                 raise ValueError("EXTRA_HEADERS must be a valid JSON string")
 
+        # --- Load CLIENT_SECRET from file ---
+        try:
+            with open(self.secret_file_path, "r") as f:
+                self.CLIENT_SECRET = f.read().strip()
+        except FileNotFoundError:
+            logging.warning(f"CLIENT_SECRET file not found at {self.secret_file_path}")
+        except Exception as e:
+            logging.error(f"Error reading CLIENT_SECRET file: {e}")
+
         return self
 
 settings = Settings()  # type: ignore[call-arg]