```diff
--- test_files/023-original.txt	2025-03-07 19:06:14
+++ test_files/023-modified.txt	2025-03-07 19:06:14
@@ -121,6 +121,10 @@
         )
         # Flatten and format the parameters structure
         params = schema_params["properties"]
+        required_params = schema_params.get("required", [])
+        for param_name, param_info in params.items():
+            if param_name not in required_params:
+                param_info["nullable"] = True
         tool = StructuredTool(
             name=action,
             description=description,
```
