fix: nullable types with gen ai bump

pyproject.toml

@@ -39,7 +39,7 @@ dependencies = [
   "google-cloud-spanner>=3.56.0, <4.0.0",                    # For Spanner database
   "google-cloud-speech>=2.30.0, <3.0.0",                     # For Audio Transcription
   "google-cloud-storage>=2.18.0, <3.0.0",                    # For GCS Artifact service
-  "google-genai>=1.41.0, <2.0.0",                            # Google GenAI SDK
+  "google-genai>=1.45.0, <2.0.0",                            # Google GenAI SDK
   "graphviz>=0.20.2, <1.0.0",                                # Graphviz for graph rendering
   "mcp>=1.8.0, <2.0.0;python_version>='3.10'",               # For MCP Toolset
   "opentelemetry-api>=1.37.0, <=1.37.0",                     # OpenTelemetry - limit upper version for sdk and api to not risk breaking changes from unstable _logs package.

src/google/adk/tools/_gemini_schema_util.py

@@ -74,31 +74,6 @@ def _to_snake_case(text: str) -> str:
   return text
 
 
-def _sanitize_schema_type(schema: dict[str, Any]) -> dict[str, Any]:
-  if ("type" not in schema or not schema["type"]) and schema.keys().isdisjoint(
-      schema
-  ):
-    schema["type"] = "object"
-  if isinstance(schema.get("type"), list):
-    nullable = False
-    non_null_type = None
-    for t in schema["type"]:
-      if t == "null":
-        nullable = True
-      elif not non_null_type:
-        non_null_type = t
-    if not non_null_type:
-      non_null_type = "object"
-    if nullable:
-      schema["type"] = [non_null_type, "null"]
-    else:
-      schema["type"] = non_null_type
-  elif schema.get("type") == "null":
-    schema["type"] = ["object", "null"]
-
-  return schema
-
-
 def _dereference_schema(schema: dict[str, Any]) -> dict[str, Any]:
   """Resolves $ref pointers in a JSON schema."""
 
@@ -183,11 +158,15 @@ def _sanitize_schema_formats_for_gemini(
     elif field_name in supported_fields and field_value is not None:
       snake_case_schema[field_name] = field_value
 
-  return _sanitize_schema_type(snake_case_schema)
+  # If the schema is empty, assume it has the type of object
+  if not snake_case_schema:
+    snake_case_schema["type"] = "object"
+
+  return snake_case_schema
 
 
 def _to_gemini_schema(openapi_schema: dict[str, Any]) -> Schema:
-  """Converts an OpenAPI schema dictionary to a Gemini Schema object."""
+  """Converts an OpenAPI v3.1. schema dictionary to a Gemini Schema object."""
   if openapi_schema is None:
     return None
 

tests/unittests/tools/test_gemini_schema_util.py

@@ -65,8 +65,9 @@ def test_to_gemini_schema_array_string_types(self):
             "nonnullable_string": {"type": ["string"]},
             "nullable_string": {"type": ["string", "null"]},
             "nullable_number": {"type": ["null", "integer"]},
-            "object_nullable": {"type": "null"},
+            "nullable_object": {"type": ["object", "null"]},
             "multi_types_nullable": {"type": ["string", "null", "integer"]},
+            "only_null": {"type": "null"},
             "empty_default_object": {},
         },
     }
@@ -84,11 +85,17 @@ def test_to_gemini_schema_array_string_types(self):
     assert gemini_schema.properties["nullable_number"].type == Type.INTEGER
     assert gemini_schema.properties["nullable_number"].nullable
 
-    assert gemini_schema.properties["object_nullable"].type == Type.OBJECT
-    assert gemini_schema.properties["object_nullable"].nullable
+    assert gemini_schema.properties["nullable_object"].type == Type.OBJECT
+    assert gemini_schema.properties["nullable_object"].nullable
 
-    assert gemini_schema.properties["multi_types_nullable"].type == Type.STRING
+    assert gemini_schema.properties["multi_types_nullable"].any_of == [
+        Schema(type=Type.STRING),
+        Schema(type=Type.INTEGER),
+    ]
     assert gemini_schema.properties["multi_types_nullable"].nullable
+
+    assert gemini_schema.properties["only_null"].type is None
+    assert gemini_schema.properties["only_null"].nullable
 
     assert gemini_schema.properties["empty_default_object"].type == Type.OBJECT
     assert gemini_schema.properties["empty_default_object"].nullable is None
@@ -146,6 +153,14 @@ def test_to_gemini_schema_any_of(self):
     assert gemini_schema.any_of[0].type == Type.STRING
     assert gemini_schema.any_of[1].type == Type.INTEGER
 
+  def test_to_gemini_schema_any_of_nullable(self):
+    openapi_schema = {
+        "anyOf": [{"type": "string"}, {"type": "null"}],
+    }
+    gemini_schema = _to_gemini_schema(openapi_schema)
+    assert gemini_schema.type == Type.STRING
+    assert gemini_schema.nullable == True
+
   def test_to_gemini_schema_general_list(self):
     openapi_schema = {
         "type": "array",
@@ -524,51 +539,6 @@ def test_sanitize_schema_formats_for_gemini(self):
         "null",
     ]
 
-  def test_sanitize_schema_formats_for_gemini_nullable(self):
-    openapi_schema = {
-        "properties": {
-            "case_id": {
-                "description": "The ID of the case.",
-                "title": "Case Id",
-                "type": "string",
-            },
-            "next_page_token": {
-                "anyOf": [{"type": "string"}, {"type": "null"}],
-                "default": None,
-                "description": (
-                    "The nextPageToken to fetch the next page of results."
-                ),
-                "title": "Next Page Token",
-            },
-        },
-        "required": ["case_id"],
-        "title": "list_alerts_by_caseArguments",
-        "type": "object",
-    }
-    openapi_schema = _sanitize_schema_formats_for_gemini(openapi_schema)
-    assert openapi_schema == {
-        "properties": {
-            "case_id": {
-                "description": "The ID of the case.",
-                "title": "Case Id",
-                "type": "string",
-            },
-            "next_page_token": {
-                "any_of": [
-                    {"type": "string"},
-                    {"type": ["object", "null"]},
-                ],
-                "description": (
-                    "The nextPageToken to fetch the next page of results."
-                ),
-                "title": "Next Page Token",
-            },
-        },
-        "required": ["case_id"],
-        "title": "list_alerts_by_caseArguments",
-        "type": "object",
-    }
-
   def test_to_gemini_schema_properties_is_none(self):
     """Tests schema conversion when 'properties' field is None."""
     openapi_schema = {"type": "object", "properties": None}