diff --git a/src/cohere/core/http_client.py b/src/cohere/core/http_client.py
index e4173f990..eced438be 100644
--- a/src/cohere/core/http_client.py
+++ b/src/cohere/core/http_client.py
@@ -10,13 +10,14 @@
 from random import random
 
 import httpx
+from httpx._types import RequestFiles
+
 from .file import File, convert_file_dict_to_httpx_tuples
 from .force_multipart import FORCE_MULTIPART
 from .jsonable_encoder import jsonable_encoder
 from .query_encoder import encode_query
 from .remove_none_from_dict import remove_none_from_dict
 from .request_options import RequestOptions
-from httpx._types import RequestFiles
 
 INITIAL_RETRY_DELAY_SECONDS = 0.5
 MAX_RETRY_DELAY_SECONDS = 10
diff --git a/src/cohere/core/jsonable_encoder.py b/src/cohere/core/jsonable_encoder.py
index afee3662d..6ea8176ad 100644
--- a/src/cohere/core/jsonable_encoder.py
+++ b/src/cohere/core/jsonable_encoder.py
@@ -17,18 +17,20 @@
 from typing import Any, Callable, Dict, List, Optional, Set, Union
 
 import pydantic
+
 from .datetime_utils import serialize_datetime
-from .pydantic_utilities import (
-    IS_PYDANTIC_V2,
-    encode_by_type,
-    to_jsonable_with_fallback,
-)
+from .pydantic_utilities import (IS_PYDANTIC_V2, encode_by_type,
+                                 to_jsonable_with_fallback)
 
 SetIntStr = Set[Union[int, str]]
 DictIntStrAny = Dict[Union[int, str], Any]
 
 
 def jsonable_encoder(obj: Any, custom_encoder: Optional[Dict[Any, Callable[[Any], Any]]] = None) -> Any:
+    # Short-circuit for most common primitive types
+    if isinstance(obj, (str, int, float, type(None))):
+        return obj
+
     custom_encoder = custom_encoder or {}
     if custom_encoder:
         if type(obj) in custom_encoder:
@@ -59,8 +61,6 @@ def jsonable_encoder(obj: Any, custom_encoder: Optional[Dict[Any, Callable[[Any]
         return obj.value
     if isinstance(obj, PurePath):
         return str(obj)
-    if isinstance(obj, (str, int, float, type(None))):
-        return obj
     if isinstance(obj, dt.datetime):
         return serialize_datetime(obj)
     if isinstance(obj, dt.date):
diff --git a/src/cohere/core/unchecked_base_model.py b/src/cohere/core/unchecked_base_model.py
index 2c2d92a7b..f2a3fd1f5 100644
--- a/src/cohere/core/unchecked_base_model.py
+++ b/src/cohere/core/unchecked_base_model.py
@@ -7,21 +7,14 @@
 
 import pydantic
 import typing_extensions
-from .pydantic_utilities import (
-    IS_PYDANTIC_V2,
-    ModelField,
-    UniversalBaseModel,
-    get_args,
-    get_origin,
-    is_literal_type,
-    is_union,
-    parse_date,
-    parse_datetime,
-    parse_obj_as,
-)
-from .serialization import get_field_to_alias_mapping
 from pydantic_core import PydanticUndefined
 
+from .pydantic_utilities import (IS_PYDANTIC_V2, ModelField,
+                                 UniversalBaseModel, get_args, get_origin,
+                                 is_literal_type, is_union, parse_date,
+                                 parse_datetime, parse_obj_as)
+from .serialization import get_field_to_alias_mapping
+
 
 class UnionMetadata:
     discriminant: str
@@ -179,6 +172,14 @@ def construct_type(*, type_: typing.Type[typing.Any], object_: typing.Any) -> ty
         return None
 
     base_type = get_origin(type_) or type_
+
+    # Early fast return for direct primitive types
+    if base_type in (str, int, float, bool, type(None)):
+        try:
+            return base_type(object_)
+        except Exception:
+            return object_
+
     is_annotated = base_type == typing_extensions.Annotated
     maybe_annotation_members = get_args(type_)
     is_annotated_union = is_annotated and is_union(get_origin(maybe_annotation_members[0]))