fix: Add schema type sanitization to OpenAPI spec parser

This change introduces a `_sanitize_schema_types` method to the OpenAPI spec parser. This method recursively removes or filters out non-standard schema types (e.g., "Any", "Unknown") from the OpenAPI specification

Close #3704
Close #3108

Co-authored-by: George Weale <gweale@google.com>
PiperOrigin-RevId: 852986491

src/google/adk/tools/openapi_tool/openapi_spec_parser/openapi_spec_parser.py

@@ -19,6 +19,7 @@ from typing import Any
 from typing import Dict
 from typing import List
 from typing import Optional
+from typing import Set
 
 from fastapi.openapi.models import Operation
 from pydantic import BaseModel
@@ -29,6 +30,21 @@ from ..._gemini_schema_util import _to_snake_case
 from ..common.common import ApiParameter
 from .operation_parser import OperationParser
 
+# Valid JSON Schema types as per OpenAPI 3.0/3.1 specification.
+#
+# These are the only types accepted by Pydantic 2.11+ for Schema.type.
+_VALID_SCHEMA_TYPES: Set[str] = frozenset({
+    "array",
+    "boolean",
+    "integer",
+    "null",
+    "number",
+    "object",
+    "string",
+})
+
+_SCHEMA_CONTAINER_KEYS: Set[str] = frozenset({"schema", "schemas"})
+
 
 class OperationEndpoint(BaseModel):
   base_url: str
@@ -70,9 +86,81 @@ class OpenApiSpecParser:
     """
 
     openapi_spec_dict = self._resolve_references(openapi_spec_dict)
+    openapi_spec_dict = self._sanitize_schema_types(openapi_spec_dict)
     operations = self._collect_operations(openapi_spec_dict)
     return operations
 
+  def _sanitize_schema_types(
+      self, openapi_spec: Dict[str, Any]
+  ) -> Dict[str, Any]:
+    """Recursively sanitizes schema types in an OpenAPI specification.
+
+    Pydantic 2.11+ strictly validates that schema types are one of:
+    'array', 'boolean', 'integer', 'null', 'number', 'object', 'string'.
+
+    External APIs (like Google Integration Connectors) may return schemas
+    with non-standard types like 'Any'. This method removes or converts
+    such invalid types to ensure compatibility.
+
+    Args:
+        openapi_spec: A dictionary representing the OpenAPI specification.
+
+    Returns:
+        A dictionary with invalid schema types removed or sanitized.
+    """
+    openapi_spec = copy.deepcopy(openapi_spec)
+
+    def sanitize_type_field(schema_dict: Dict[str, Any]) -> None:
+      if "type" not in schema_dict:
+        return
+
+      type_value = schema_dict["type"]
+      if isinstance(type_value, str):
+        normalized_type = type_value.lower()
+        if normalized_type in _VALID_SCHEMA_TYPES:
+          schema_dict["type"] = normalized_type
+          return
+
+        del schema_dict["type"]
+        return
+
+      if isinstance(type_value, list):
+        valid_types = []
+        for entry in type_value:
+          if not isinstance(entry, str):
+            continue
+
+          normalized_entry = entry.lower()
+          if normalized_entry not in _VALID_SCHEMA_TYPES:
+            continue
+
+          if normalized_entry not in valid_types:
+            valid_types.append(normalized_entry)
+
+        if valid_types:
+          schema_dict["type"] = valid_types
+        else:
+          del schema_dict["type"]
+
+    def sanitize_recursive(obj: Any, *, in_schema: bool) -> Any:
+      if isinstance(obj, dict):
+        if in_schema:
+          sanitize_type_field(obj)
+
+        # Recursively process all values in the dict
+        for key, value in obj.items():
+          obj[key] = sanitize_recursive(
+              value,
+              in_schema=in_schema or key in _SCHEMA_CONTAINER_KEYS,
+          )
+        return obj
+      elif isinstance(obj, list):
+        return [sanitize_recursive(item, in_schema=in_schema) for item in obj]
+      else:
+        return obj
+
+    return sanitize_recursive(openapi_spec, in_schema=False)
+
   def _collect_operations(
       self, openapi_spec: Dict[str, Any]
   ) -> List[ParsedOperation]:

tests/unittests/tools/openapi_tool/openapi_spec_parser/test_openapi_spec_parser.py

@@ -681,3 +681,186 @@ def test_parse_spec_with_path_level_parameters(openapi_spec_generator):
   assert local_param is not None
   assert local_param.param_location == "header"
   assert local_param.type_value is int
+
+
+def test_parse_spec_with_invalid_type_any(openapi_spec_generator):
+  """Test that schemas with type='Any' are sanitized for Pydantic 2.11+.
+
+  External APIs like Google Integration Connectors may return schemas with
+  non-standard types like 'Any'. This test verifies that such types are
+  removed to allow parsing to succeed.
+  """
+  openapi_spec = {
+      "openapi": "3.1.0",
+      "info": {"title": "API with Any type", "version": "1.0.0"},
+      "paths": {
+          "/test": {
+              "get": {
+                  "operationId": "testAnyType",
+                  "responses": {
+                      "200": {
+                          "description": "Success",
+                          "content": {
+                              "application/json": {"schema": {"type": "Any"}}
+                          },
+                      }
+                  },
+              }
+          }
+      },
+  }
+
+  # This should not raise a ValidationError
+  parsed_operations = openapi_spec_generator.parse(openapi_spec)
+
+  assert len(parsed_operations) == 1
+  assert parsed_operations[0].name == "test_any_type"
+
+
+def test_parse_spec_with_nested_invalid_types(openapi_spec_generator):
+  """Test that nested schemas with invalid types are sanitized."""
+  openapi_spec = {
+      "openapi": "3.1.0",
+      "info": {"title": "Nested Invalid Types API", "version": "1.0.0"},
+      "paths": {
+          "/test": {
+              "post": {
+                  "operationId": "testNestedInvalid",
+                  "requestBody": {
+                      "content": {
+                          "application/json": {
+                              "schema": {
+                                  "type": "object",
+                                  "properties": {
+                                      "valid_prop": {"type": "string"},
+                                      "invalid_prop": {"type": "Unknown"},
+                                      "nested_obj": {
+                                          "type": "object",
+                                          "properties": {
+                                              "deeply_invalid": {
+                                                  "type": "CustomType"
+                                              }
+                                          },
+                                      },
+                                  },
+                              }
+                          }
+                      }
+                  },
+                  "responses": {"200": {"description": "OK"}},
+              }
+          }
+      },
+  }
+
+  # This should not raise a ValidationError
+  parsed_operations = openapi_spec_generator.parse(openapi_spec)
+
+  assert len(parsed_operations) == 1
+  op = parsed_operations[0]
+  # The valid properties should still be parsed
+  param_names = [p.original_name for p in op.parameters]
+  assert "valid_prop" in param_names
+  assert "invalid_prop" in param_names
+  assert "nested_obj" in param_names
+
+
+def test_parse_spec_with_type_list_containing_invalid(openapi_spec_generator):
+  """Test that type arrays with invalid values are filtered."""
+  openapi_spec = {
+      "openapi": "3.1.0",
+      "info": {"title": "Type List API", "version": "1.0.0"},
+      "paths": {
+          "/test": {
+              "get": {
+                  "operationId": "testTypeList",
+                  "responses": {
+                      "200": {
+                          "description": "Success",
+                          "content": {
+                              "application/json": {
+                                  "schema": {"type": ["string", "Any", "null"]}
+                              }
+                          },
+                      }
+                  },
+              }
+          }
+      },
+  }
+
+  # This should not raise a ValidationError
+  parsed_operations = openapi_spec_generator.parse(openapi_spec)
+
+  assert len(parsed_operations) == 1
+
+
+def test_sanitize_schema_types_removes_invalid_types(openapi_spec_generator):
+  """Test that _sanitize_schema_types correctly handles invalid types."""
+  spec_with_invalid = {
+      "components": {
+          "schemas": {
+              "InvalidSchema": {"type": "Any", "description": "Invalid type"},
+              "ValidSchema": {"type": "string", "description": "Valid type"},
+          }
+      }
+  }
+
+  sanitized = openapi_spec_generator._sanitize_schema_types(spec_with_invalid)
+
+  # Invalid type should be removed
+  assert "type" not in sanitized["components"]["schemas"]["InvalidSchema"]
+  assert (
+      sanitized["components"]["schemas"]["InvalidSchema"]["description"]
+      == "Invalid type"
+  )
+
+  # Valid type should be preserved
+  assert sanitized["components"]["schemas"]["ValidSchema"]["type"] == "string"
+
+
+def test_sanitize_schema_types_does_not_touch_security_schemes(
+    openapi_spec_generator,
+):
+  """Test that schema type sanitization does not affect security schemes."""
+  spec = {
+      "components": {
+          "schemas": {"InvalidSchema": {"type": "Any"}},
+          "securitySchemes": {
+              "api_key": {
+                  "type": "apiKey",
+                  "in": "header",
+                  "name": "X-API-Key",
+              }
+          },
+      }
+  }
+
+  sanitized = openapi_spec_generator._sanitize_schema_types(spec)
+
+  assert "type" not in sanitized["components"]["schemas"]["InvalidSchema"]
+  assert (
+      sanitized["components"]["securitySchemes"]["api_key"]["type"] == "apiKey"
+  )
+
+
+def test_sanitize_schema_types_filters_type_lists(openapi_spec_generator):
+  """Test that type lists with invalid values are filtered."""
+  spec_with_list = {"schema": {"type": ["string", "Any", "null", "Unknown"]}}
+
+  sanitized = openapi_spec_generator._sanitize_schema_types(spec_with_list)
+
+  # Only valid types should remain
+  assert sanitized["schema"]["type"] == ["string", "null"]
+
+
+def test_sanitize_schema_types_removes_all_invalid_list(openapi_spec_generator):
+  """Test that type field is removed when all list values are invalid."""
+  spec_with_all_invalid = {"schema": {"type": ["Any", "Unknown", "Custom"]}}
+
+  sanitized = openapi_spec_generator._sanitize_schema_types(
+      spec_with_all_invalid
+  )
+
+  # Type field should be removed entirely
+  assert "type" not in sanitized["schema"]