diff --git a/guardrails/llm_providers.py b/guardrails/llm_providers.py
index c115a969e..f34506a3f 100644
--- a/guardrails/llm_providers.py
+++ b/guardrails/llm_providers.py
@@ -1,5 +1,16 @@
 import asyncio
-from typing import Any, Awaitable, Callable, Dict, Iterable, List, Optional, Union, cast
+from typing import (
+    Any,
+    Awaitable,
+    Callable,
+    Dict,
+    Iterable,
+    List,
+    Optional,
+    Type,
+    Union,
+    cast,
+)
 
 from guardrails_api_client.models.validate_payload_llm_api import ValidatePayloadLlmApi
 from pydantic import BaseModel
@@ -154,7 +165,9 @@ def _invoke_llm(
         model: str = "gpt-3.5-turbo",
         instructions: Optional[str] = None,
         msg_history: Optional[List[Dict]] = None,
-        base_model: Optional[BaseModel] = None,
+        base_model: Optional[
+            Union[Type[BaseModel], Type[List[Type[BaseModel]]]]
+        ] = None,
         function_call: Optional[Any] = None,
         *args,
         **kwargs,
@@ -184,13 +197,15 @@ def _invoke_llm(
             )
 
         # Configure function calling if applicable (only for non-streaming)
+        fn_kwargs = {}
         if base_model and not kwargs.get("stream", False):
-            function_params = [convert_pydantic_model_to_openai_fn(base_model)]
-            if function_call is None:
-                function_call = {"name": function_params[0]["name"]}
-            fn_kwargs = {"functions": function_params, "function_call": function_call}
-        else:
-            fn_kwargs = {}
+            function_params = convert_pydantic_model_to_openai_fn(base_model)
+            if function_call is None and function_params:
+                function_call = {"name": function_params["name"]}
+                fn_kwargs = {
+                    "functions": [function_params],
+                    "function_call": function_call,
+                }
 
         # Call OpenAI
         if "api_key" in kwargs:
@@ -688,7 +703,9 @@ async def invoke_llm(
         model: str = "gpt-3.5-turbo",
         instructions: Optional[str] = None,
         msg_history: Optional[List[Dict]] = None,
-        base_model: Optional[BaseModel] = None,
+        base_model: Optional[
+            Union[Type[BaseModel], Type[List[Type[BaseModel]]]]
+        ] = None,
         function_call: Optional[Any] = None,
         *args,
         **kwargs,
@@ -718,13 +735,15 @@ async def invoke_llm(
             )
 
         # Configure function calling if applicable
+        fn_kwargs = {}
         if base_model:
-            function_params = [convert_pydantic_model_to_openai_fn(base_model)]
-            if function_call is None:
-                function_call = {"name": function_params[0]["name"]}
-            fn_kwargs = {"functions": function_params, "function_call": function_call}
-        else:
-            fn_kwargs = {}
+            function_params = convert_pydantic_model_to_openai_fn(base_model)
+            if function_call is None and function_params:
+                function_call = {"name": function_params["name"]}
+                fn_kwargs = {
+                    "functions": [function_params],
+                    "function_call": function_call,
+                }
 
         # Call OpenAI
         if "api_key" in kwargs:
diff --git a/guardrails/utils/dataclass.py b/guardrails/utils/dataclass.py
new file mode 100644
index 000000000..92bdb81ce
--- /dev/null
+++ b/guardrails/utils/dataclass.py
@@ -0,0 +1,11 @@
+import pydantic.version
+
+PYDANTIC_VERSION = pydantic.version.VERSION
+
+if PYDANTIC_VERSION.startswith("1"):
+
+    def dataclass(cls):  # type: ignore
+        return cls
+
+else:
+    from dataclasses import dataclass  # type: ignore  # noqa
diff --git a/guardrails/utils/pydantic_utils/v1.py b/guardrails/utils/pydantic_utils/v1.py
index 00bf5103c..9e29466af 100644
--- a/guardrails/utils/pydantic_utils/v1.py
+++ b/guardrails/utils/pydantic_utils/v1.py
@@ -4,7 +4,17 @@
 from copy import deepcopy
 from datetime import date, time
 from enum import Enum
-from typing import Any, Callable, Dict, Optional, Type, Union, get_args, get_origin
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    List,
+    Optional,
+    Type,
+    Union,
+    get_args,
+    get_origin,
+)
 
 from pydantic import BaseModel, validator
 from pydantic.fields import ModelField
@@ -22,6 +32,7 @@
 from guardrails.datatypes import Object as ObjectDataType
 from guardrails.datatypes import String as StringDataType
 from guardrails.datatypes import Time as TimeDataType
+from guardrails.utils.safe_get import safe_get
 from guardrails.validator_base import Validator
 from guardrails.validatorsattr import ValidatorsAttr
 
@@ -228,7 +239,78 @@ def process_validators(vals, fld):
     return model_fields
 
 
-def convert_pydantic_model_to_openai_fn(model: BaseModel) -> Dict:
+def create_bare_model(model: Type[BaseModel]):
+    class BareModel(BaseModel):
+        __annotations__ = getattr(model, "__annotations__", {})
+
+    return BareModel
+
+
+def reduce_to_annotations(type_annotation: Any) -> Type[Any]:
+    if (
+        type_annotation
+        and isinstance(type_annotation, type)
+        and issubclass(type_annotation, BaseModel)
+    ):
+        return create_bare_model(type_annotation)
+    return type_annotation
+
+
+def find_models_in_type(type_annotation: Any) -> Type[Any]:
+    type_origin = get_origin(type_annotation)
+    inner_types = get_args(type_annotation)
+    if type_origin == Union:
+        data_types = tuple([find_models_in_type(t) for t in inner_types])
+        return Type[Union[data_types]]  # type: ignore
+    elif type_origin == list:
+        if len(inner_types) > 1:
+            raise ValueError("List data type must have exactly one child.")
+        # No List[List] support; we've already declared that in our types
+        item_type = safe_get(inner_types, 0)
+        return Type[List[find_models_in_type(item_type)]]
+    elif type_origin == dict:
+        # First arg is key which must be primitive
+        # Second arg is potentially a model
+        key_value_type = safe_get(inner_types, 1)
+        value_value_type = safe_get(inner_types, 1)
+        return Type[Dict[key_value_type, find_models_in_type(value_value_type)]]
+    else:
+        return reduce_to_annotations(type_annotation)
+
+
+def schema_to_bare_model(model: Type[BaseModel]) -> Type[BaseModel]:
+    copy = deepcopy(model)
+    for field_key in copy.__fields__:
+        field = copy.__fields__.get(field_key)
+        if field:
+            extras = field.field_info.extra
+            if "validators" in extras:
+                extras["format"] = list(
+                    v.to_prompt()
+                    for v in extras.pop("validators", [])
+                    if hasattr(v, "to_prompt")
+                )
+
+            field.field_info.extra = extras
+
+            value_type = find_models_in_type(field.annotation)
+            field.annotation = value_type
+            copy.__fields__[field_key] = field
+
+    # root_model = reduce_to_annotations(model)
+
+    # for key in root_model.__annotations__:
+    #     value = root_model.__annotations__.get(key)
+    #     print("value.field_info: ", value.field_info)
+    #     value_type = find_models_in_type(value)
+    #     root_model.__annotations__[key] = value_type
+
+    return copy
+
+
+def convert_pydantic_model_to_openai_fn(
+    model: Union[Type[BaseModel], Type[List[Type[BaseModel]]]]
+) -> Dict:
     """Convert a Pydantic BaseModel to an OpenAI function.
 
     Args:
@@ -237,23 +319,41 @@ def convert_pydantic_model_to_openai_fn(model: BaseModel) -> Dict:
     Returns:
         OpenAI function paramters.
     """
-
-    # Create a bare model with no extra fields
-    class BareModel(BaseModel):
-        __annotations__ = model.__annotations__
-
-    # Convert Pydantic model to JSON schema
-    json_schema = BareModel.schema()
-
-    # Create OpenAI function parameters
-    fn_params = {
-        "name": json_schema["title"],
-        "parameters": json_schema,
-    }
-    if "description" in json_schema and json_schema["description"] is not None:
-        fn_params["description"] = json_schema["description"]
-
-    return fn_params
+    return {}
+
+    # schema_model = model
+
+    # type_origin = get_origin(model)
+    # if type_origin == list:
+    #     item_types = get_args(model)
+    #     if len(item_types) > 1:
+    #         raise ValueError("List data type must have exactly one child.")
+    #     # No List[List] support; we've already declared that in our types
+    #     schema_model = safe_get(item_types, 0)
+
+    # # Create a bare model with no extra fields
+    # bare_model = schema_to_bare_model(schema_model)
+
+    # # Convert Pydantic model to JSON schema
+    # json_schema = bare_model.schema()
+    # json_schema["title"] = schema_model.__name__
+
+    # if type_origin == list:
+    #     json_schema = {
+    #         "title": f"Array<{json_schema.get('title')}>",
+    #         "type": "array",
+    #         "items": json_schema,
+    #     }
+
+    # # Create OpenAI function parameters
+    # fn_params = {
+    #     "name": json_schema["title"],
+    #     "parameters": json_schema,
+    # }
+    # if "description" in json_schema and json_schema["description"] is not None:
+    #     fn_params["description"] = json_schema["description"]
+
+    # return fn_params
 
 
 def field_to_datatype(field: Union[ModelField, Type]) -> Type[DataType]:
diff --git a/guardrails/utils/pydantic_utils/v2.py b/guardrails/utils/pydantic_utils/v2.py
index 3c9ca6c84..5c135caca 100644
--- a/guardrails/utils/pydantic_utils/v2.py
+++ b/guardrails/utils/pydantic_utils/v2.py
@@ -3,7 +3,19 @@
 from copy import deepcopy
 from datetime import date, time
 from enum import Enum
-from typing import Any, Callable, Dict, List, Optional, Type, TypeVar, Union, get_args
+from typing import (
+    Any,
+    Callable,
+    Dict,
+    List,
+    Optional,
+    Type,
+    TypeVar,
+    Union,
+    cast,
+    get_args,
+    get_origin,
+)
 
 from pydantic import BaseModel, ConfigDict, field_validator
 from pydantic.fields import FieldInfo
@@ -21,6 +33,7 @@
 from guardrails.datatypes import Object as ObjectDataType
 from guardrails.datatypes import String as StringDataType
 from guardrails.datatypes import Time as TimeDataType
+from guardrails.utils.safe_get import safe_get
 from guardrails.validator_base import Validator
 from guardrails.validatorsattr import ValidatorsAttr
 
@@ -114,14 +127,9 @@ def is_enum(type_annotation: Any) -> bool:
     return False
 
 
-def _create_bare_model(model: Type[BaseModel]) -> Type[BaseModel]:
-    class BareModel(BaseModel):
-        __annotations__ = getattr(model, "__annotations__", {})
-
-    return BareModel
-
-
-def convert_pydantic_model_to_openai_fn(model: BaseModel) -> Dict:
+def convert_pydantic_model_to_openai_fn(
+    model: Union[Type[BaseModel], Type[List[Type[BaseModel]]]]
+) -> Dict:
     """Convert a Pydantic BaseModel to an OpenAI function.
 
     Args:
@@ -131,10 +139,28 @@ def convert_pydantic_model_to_openai_fn(model: BaseModel) -> Dict:
         OpenAI function paramters.
     """
 
-    bare_model = _create_bare_model(type(model))
+    schema_model = model
+
+    type_origin = get_origin(model)
+    if type_origin == list:
+        item_types = get_args(model)
+        if len(item_types) > 1:
+            raise ValueError("List data type must have exactly one child.")
+        # No List[List] support; we've already declared that in our types
+        schema_model = safe_get(item_types, 0)
+
+    schema_model = cast(Type[BaseModel], schema_model)
 
     # Convert Pydantic model to JSON schema
-    json_schema = bare_model.model_json_schema()
+    json_schema = schema_model.model_json_schema()
+    json_schema["title"] = schema_model.__name__
+
+    if type_origin == list:
+        json_schema = {
+            "title": f"Array<{json_schema.get('title')}>",
+            "type": "array",
+            "items": json_schema,
+        }
 
     # Create OpenAI function parameters
     fn_params = {
diff --git a/guardrails/validator_base.py b/guardrails/validator_base.py
index 7c56eac70..be32449ba 100644
--- a/guardrails/validator_base.py
+++ b/guardrails/validator_base.py
@@ -23,6 +23,7 @@
 from guardrails.classes import InputType
 from guardrails.constants import hub
 from guardrails.errors import ValidationError
+from guardrails.utils.dataclass import dataclass
 
 VALIDATOR_IMPORT_WARNING = """Accessing `{validator_name}` using
 `from guardrails.validators import {validator_name}` is deprecated and
@@ -372,10 +373,11 @@ class FailResult(ValidationResult):
     fix_value: Optional[Any] = None
 
 
+@dataclass  # type: ignore
 class Validator(Runnable):
     """Base class for validators."""
 
-    rail_alias: str
+    rail_alias: str = ""
 
     run_in_separate_process = False
     override_value_on_pass = False
diff --git a/tests/unit_tests/utils/pydantic_utils/v1.py b/tests/unit_tests/utils/pydantic_utils/v1.py
new file mode 100644
index 000000000..a9322c8d2
--- /dev/null
+++ b/tests/unit_tests/utils/pydantic_utils/v1.py
@@ -0,0 +1,84 @@
+from copy import deepcopy
+from typing import List
+from warnings import warn
+
+import pydantic.version
+import pytest
+from pydantic import BaseModel, Field
+
+from guardrails.utils.pydantic_utils.v1 import convert_pydantic_model_to_openai_fn
+
+PYDANTIC_VERSION = pydantic.version.VERSION
+
+
+class Foo(BaseModel):
+    bar: str = Field(description="some string value")
+
+
+# fmt: off
+foo_schema = {
+    "title": "Foo",
+    "type": "object",
+    "properties": {
+        "bar": {
+            "title": "Bar",
+            "description": "some string value",
+            "type": "string"
+        }
+    },
+    "required": [
+        "bar"
+    ]
+}
+# fmt: on
+
+
+# This test is descriptive, not prescriptive.
+@pytest.mark.skipif(
+    not PYDANTIC_VERSION.startswith("1"),
+    reason="Tests function calling syntax for Pydantic v1",
+)
+class TestConvertPydanticModelToOpenaiFn:
+    def test_object_schema(self):
+        expected_schema = deepcopy(foo_schema)
+        # When pushed through BareModel it loses the description on any properties.
+        del expected_schema["properties"]["bar"]["description"]
+
+        # fmt: off
+        expected_fn_params = {  # noqa
+            "name": "Foo",
+            "parameters": expected_schema
+        }
+        # fmt: on
+
+        actual_fn_params = convert_pydantic_model_to_openai_fn(Foo)
+
+        # assert actual_fn_params == expected_fn_params
+        warn("Function calling is disabled for pydantic 1.x")
+        assert actual_fn_params == {}
+
+    def test_list_schema(self):
+        expected_schema = deepcopy(foo_schema)
+        # When pushed through BareModel it loses the description on any properties.
+        del expected_schema["properties"]["bar"]["description"]
+
+        # fmt: off
+        expected_schema = {
+            "title": f"Array<{expected_schema.get('title')}>",
+            "type": "array",
+            "items": expected_schema
+        }
+        # fmt: on
+
+        # fmt: off
+        expected_fn_params = {  # noqa
+            "name": "Array<Foo>",
+            "parameters": expected_schema
+        }
+        # fmt: on
+
+        actual_fn_params = convert_pydantic_model_to_openai_fn(List[Foo])
+
+        # assert actual_fn_params == expected_fn_params
+        warn("Function calling is disabled for pydantic 1.x")
+        assert actual_fn_params == {}
diff --git a/tests/unit_tests/utils/pydantic_utils/v2.py b/tests/unit_tests/utils/pydantic_utils/v2.py
new file mode 100644
index 000000000..32f6e98d9
--- /dev/null
+++ b/tests/unit_tests/utils/pydantic_utils/v2.py
@@ -0,0 +1,75 @@
+from copy import deepcopy
+from typing import List
+
+import pydantic.version
+import pytest
+from pydantic import BaseModel, Field
+
+from guardrails.utils.pydantic_utils.v2 import convert_pydantic_model_to_openai_fn
+
+PYDANTIC_VERSION = pydantic.version.VERSION
+
+
+class Foo(BaseModel):
+    bar: str = Field(description="some string value")
+
+
+# fmt: off
+foo_schema = {
+    "title": "Foo",
+    "type": "object",
+    "properties": {
+        "bar": {
+            "title": "Bar",
+            "description": "some string value",
+            "type": "string"
+        }
+    },
+    "required": [
+        "bar"
+    ]
+}
+# fmt: on
+
+
+# This test is descriptive, not prescriptive.
+@pytest.mark.skipif(
+    not PYDANTIC_VERSION.startswith("2"),
+    reason="Tests function calling syntax for Pydantic v2",
+)
+class TestConvertPydanticModelToOpenaiFn:
+    def test_object_schema(self):
+        expected_schema = deepcopy(foo_schema)
+
+        # fmt: off
+        expected_fn_params = {
+            "name": "Foo",
+            "parameters": expected_schema
+        }
+        # fmt: on
+
+        actual_fn_params = convert_pydantic_model_to_openai_fn(Foo)
+
+        assert actual_fn_params == expected_fn_params
+
+    def test_list_schema(self):
+        expected_schema = deepcopy(foo_schema)
+
+        # fmt: off
+        expected_schema = {
+            "title": f"Array<{expected_schema.get('title')}>",
+            "type": "array",
+            "items": expected_schema
+        }
+        # fmt: on
+
+        # fmt: off
+        expected_fn_params = {
+            "name": "Array<Foo>",
+            "parameters": expected_schema
+        }
+        # fmt: on
+
+        actual_fn_params = convert_pydantic_model_to_openai_fn(List[Foo])
+
+        assert actual_fn_params == expected_fn_params