diff --git a/tools/skills_tool.py b/tools/skills_tool.py
index 6ff54230d..40a6990ea 100644
--- a/tools/skills_tool.py
+++ b/tools/skills_tool.py
@@ -111,7 +111,7 @@ def load_env() -> Dict[str, str]:
     if not env_path.exists():
         return env_vars
 
-    with env_path.open() as f:
+    with env_path.open(encoding="utf-8") as f:
         for line in f:
             line = line.strip()
             if line and not line.startswith("#") and "=" in line: