diff --git a/src/aegis_gitea_mcp/stdio_app.py b/src/aegis_gitea_mcp/stdio_app.py
index 6d79a87..f912b7d 100644
--- a/src/aegis_gitea_mcp/stdio_app.py
+++ b/src/aegis_gitea_mcp/stdio_app.py
@@ -74,7 +74,9 @@ def _bootstrap_env() -> None:
 
 def _check_required_env() -> None:
     """Fail with an actionable message when required env vars are missing."""
-    missing = [name for name in ("GITEA_URL", "GITEA_TOKEN") if not os.environ.get(name, "").strip()]
+    missing = [
+        name for name in ("GITEA_URL", "GITEA_TOKEN") if not os.environ.get(name, "").strip()
+    ]
     if missing:
         raise StdioConfigError(
             "Missing required environment variable(s): "