diff --git a/requirements-dev.lock b/requirements-dev.lock
index caad919a..ba25fc75 100644
--- a/requirements-dev.lock
+++ b/requirements-dev.lock
@@ -49,7 +49,7 @@ markdown-it-py==3.0.0
     # via rich
 mdurl==0.1.2
     # via markdown-it-py
-mypy==1.7.1
+mypy==1.10.1
 mypy-extensions==1.0.0
     # via mypy
 nodeenv==1.8.0
diff --git a/src/python_minus_intercom/_base_client.py b/src/python_minus_intercom/_base_client.py
index 2e37ff42..a0253f13 100644
--- a/src/python_minus_intercom/_base_client.py
+++ b/src/python_minus_intercom/_base_client.py
@@ -955,6 +955,11 @@ def _request(
         stream: bool,
         stream_cls: type[_StreamT] | None,
     ) -> ResponseT | _StreamT:
+        # create a copy of the options we were given so that if the
+        # options are mutated later & we then retry, the retries are
+        # given the original options
+        input_options = model_copy(options)
+
         cast_to = self._maybe_override_cast_to(cast_to, options)
         self._prepare_options(options)
 
@@ -979,7 +984,7 @@ def _request(
 
             if retries > 0:
                 return self._retry_request(
-                    options,
+                    input_options,
                     cast_to,
                     retries,
                     stream=stream,
@@ -994,7 +999,7 @@ def _request(
 
             if retries > 0:
                 return self._retry_request(
-                    options,
+                    input_options,
                     cast_to,
                     retries,
                     stream=stream,
@@ -1022,7 +1027,7 @@ def _request(
             if retries > 0 and self._should_retry(err.response):
                 err.response.close()
                 return self._retry_request(
-                    options,
+                    input_options,
                     cast_to,
                     retries,
                     err.response.headers,
@@ -1518,6 +1523,11 @@ async def _request(
             # execute it earlier while we are in an async context
             self._platform = await asyncify(get_platform)()
 
+        # create a copy of the options we were given so that if the
+        # options are mutated later & we then retry, the retries are
+        # given the original options
+        input_options = model_copy(options)
+
         cast_to = self._maybe_override_cast_to(cast_to, options)
         await self._prepare_options(options)
 
@@ -1540,7 +1550,7 @@ async def _request(
 
             if retries > 0:
                 return await self._retry_request(
-                    options,
+                    input_options,
                     cast_to,
                     retries,
                     stream=stream,
@@ -1555,7 +1565,7 @@ async def _request(
 
             if retries > 0:
                 return await self._retry_request(
-                    options,
+                    input_options,
                     cast_to,
                     retries,
                     stream=stream,
@@ -1578,7 +1588,7 @@ async def _request(
             if retries > 0 and self._should_retry(err.response):
                 await err.response.aclose()
                 return await self._retry_request(
-                    options,
+                    input_options,
                     cast_to,
                     retries,
                     err.response.headers,
diff --git a/src/python_minus_intercom/_models.py b/src/python_minus_intercom/_models.py
index 5d95bb4b..eb7ce3bd 100644
--- a/src/python_minus_intercom/_models.py
+++ b/src/python_minus_intercom/_models.py
@@ -643,6 +643,14 @@ def validate_type(*, type_: type[_T], value: object) -> _T:
     return cast(_T, _validate_non_model_type(type_=type_, value=value))
 
 
+def set_pydantic_config(typ: Any, config: pydantic.ConfigDict) -> None:
+    """Add a pydantic config for the given type.
+
+    Note: this is a no-op on Pydantic v1.
+    """
+    setattr(typ, "__pydantic_config__", config)  # noqa: B010
+
+
 # our use of subclasssing here causes weirdness for type checkers,
 # so we just pretend that we don't subclass
 if TYPE_CHECKING: