fix error

tools.py

@@ -1,5 +1,6 @@
 import random
 from abc import ABC, abstractmethod
+from typing import get_origin, get_args
 import os
 # from langchain.tools import tool
 import json
@@ -8,6 +9,7 @@ from openai import OpenAI
 from typing import Dict, Optional, Union
 import random
 import copy
+from types import UnionType
 
 
 
@@ -50,8 +52,21 @@ class ToolBase(BaseModel, ABC):
         for field_name, field_info in cls.model_fields.items():
             # Field properties
             field_type = "string"  # Default to string, will adjust if it's a different type
-            annotation = field_info.annotation.__args__[0] if getattr(field_info.annotation, "__origin__", None) is Union else field_info.annotation 
-
+            annotation = field_info.annotation.__args__[0] if getattr(field_info.annotation, "__origin__", None) is Union else field_info.annotation
+            
+            has_none = False
+            if get_origin(annotation) is UnionType:  # Check if it's a Union type
+                args = get_args(annotation)
+                if type(None) in args:
+                    has_none = True
+                args = [arg for arg in args if type(None) != arg]
+                if len(args) > 1:
+                    raise TypeError("It can be union of only a valid type (str, int, bool, etc) and None")
+                elif len(args) == 0:
+                    raise TypeError("There must be a valid type (str, int, bool, etc) not only None")
+                else:
+                    annotation = args[0]
+            
             if annotation == int:
                 field_type = "integer"
             elif annotation == bool:
@@ -66,10 +81,13 @@ class ToolBase(BaseModel, ABC):
             # Determine if the field is required (not Optional or None)
             if field_info.is_required():
                 function_metadata["function"]["parameters"]["required"].append(field_name)
+                has_none = True
 
             # If there's an enum (like for `unit`), add it to the properties
             if hasattr(field_info, 'default') and field_info.default is not None and isinstance(field_info.default, list):
                 function_metadata["function"]["parameters"]["properties"][field_name]["enum"] = field_info.default
+                if not has_none:
+                    function_metadata["function"]["parameters"]["required"].append(field_name)
 
         return function_metadata
 
@@ -309,7 +327,7 @@ class modify_reservation(ToolBase):
     """
 
 
-    new_room_type: str = Field(default=list(json_data["room_types"].keys()) + [None], description=f"The type of new room to be modified, if {None} same room will be modified.")
+    new_room_type: str | None = Field(default=list(json_data["room_types"].keys()), description=f"The type of new room to be modified, if {None} same room will be modified.")
     new_check_in_date: str = Field(default=None, description="New check out date in format DD/MM/YYYY")
     new_check_out_date: str = Field(default=None, description="New check out date in format DD/MM/YYYY")
     guests: int = Field(default=None, description="New number of guests for the reservation.")