update docs

Author: LingXuanYin

litellm/llms/volcengine/chat/transformation.py

@@ -97,9 +97,9 @@ def map_openai_params(
                 and isinstance(thinking_value, dict)
                 and thinking_value.get("type", None) in ["enabled", "disabled", "auto"],  # legal values, see docs
             ):
-                # Add thinking parameter to extra_body for all other cases
+                # Add thinking parameter to extra_body for all legal cases
                 optional_params.setdefault("extra_body", {})["thinking"] = thinking_value
             else:
-                # Skip adding thinking parameter when it's not set
+                # Skip adding thinking parameter when it's not set or has invalid value
                 pass
         return optional_params

tests/test_litellm/llms/volcengine/test_volcengine.py

@@ -24,7 +24,7 @@ def test_get_optional_params(self):
             drop_params=False,
         )
 
-        # Fixed: thinking disabled should be omitted from extra_body
+        # Fixed: thinking disabled should appear in extra_body
         assert mapped_params == {
             "extra_body": {"thinking": {"type": "disabled"}}
         }