diff --git a/pyrightconfig.stricter.json b/pyrightconfig.stricter.json
index 53c544e7d..2dd95c47a 100644
--- a/pyrightconfig.stricter.json
+++ b/pyrightconfig.stricter.json
@@ -64,7 +64,6 @@
         "stubs/redis",
         "stubs/requests",
         "stubs/setuptools",
-        "stubs/slumber",
         "stubs/SQLAlchemy",
         "stubs/stripe",
         "stubs/tqdm",
diff --git a/stubs/slumber/METADATA.toml b/stubs/slumber/METADATA.toml
index 161ee7abb..baa0cc547 100644
--- a/stubs/slumber/METADATA.toml
+++ b/stubs/slumber/METADATA.toml
@@ -1,4 +1,5 @@
 version = "0.7.*"
+requires = ["types-requests"]
 
 [tool.stubtest]
 ignore_missing_stub = false
diff --git a/stubs/slumber/slumber/__init__.pyi b/stubs/slumber/slumber/__init__.pyi
index 8d6f59e49..b03c170ca 100644
--- a/stubs/slumber/slumber/__init__.pyi
+++ b/stubs/slumber/slumber/__init__.pyi
@@ -1,30 +1,39 @@
+from _typeshed import Self
 from typing import Any
 
+from requests import Response, Session
+from requests.sessions import _Auth, _Data, _Files
+
+from .serialize import Serializer
+
+__all__ = ["Resource", "API"]
+
 class ResourceAttributesMixin:
-    def __getattr__(self, item): ...
+    # Exists at runtime:
+    def __getattr__(self, item: str) -> Any: ...
 
 class Resource(ResourceAttributesMixin):
-    def __init__(self, *args, **kwargs) -> None: ...
-    def __call__(self, id: Any | None = ..., format: Any | None = ..., url_override: Any | None = ...): ...
-    def as_raw(self): ...
-    def get(self, **kwargs): ...
-    def options(self, **kwargs): ...
-    def head(self, **kwargs): ...
-    def post(self, data: Any | None = ..., files: Any | None = ..., **kwargs): ...
-    def patch(self, data: Any | None = ..., files: Any | None = ..., **kwargs): ...
-    def put(self, data: Any | None = ..., files: Any | None = ..., **kwargs): ...
-    def delete(self, **kwargs): ...
-    def url(self): ...
+    def __init__(self, *args: Any, **kwargs: Any) -> None: ...
+    def __call__(self: Self, id: str | None = ..., format: str | None = ..., url_override: str | None = ...) -> Self: ...
+    def as_raw(self: Self) -> Self: ...
+    def get(self, **kwargs: Any) -> Response: ...
+    def options(self, **kwargs: Any) -> Response: ...
+    def head(self, **kwargs: Any) -> Response: ...
+    def post(self, data: _Data | None = ..., files: _Files | None = ..., **kwargs: Any) -> Response: ...
+    def patch(self, data: _Data | None = ..., files: _Files | None = ..., **kwargs: Any) -> Response: ...
+    def put(self, data: _Data | None = ..., files: _Files | None = ..., **kwargs: Any) -> Response: ...
+    def delete(self, **kwargs: Any) -> Response: ...
+    def url(self) -> str: ...
 
 class API(ResourceAttributesMixin):
-    resource_class: Any
+    resource_class: type[Resource]
     def __init__(
         self,
-        base_url: Any | None = ...,
-        auth: Any | None = ...,
-        format: Any | None = ...,
+        base_url: str | None = ...,
+        auth: _Auth | None = ...,
+        format: str | None = ...,
         append_slash: bool = ...,
-        session: Any | None = ...,
-        serializer: Any | None = ...,
+        session: Session | None = ...,
+        serializer: Serializer | None = ...,
         raw: bool = ...,
     ) -> None: ...
diff --git a/stubs/slumber/slumber/exceptions.pyi b/stubs/slumber/slumber/exceptions.pyi
index a077fd22a..20cac92d7 100644
--- a/stubs/slumber/slumber/exceptions.pyi
+++ b/stubs/slumber/slumber/exceptions.pyi
@@ -1,7 +1,9 @@
+from typing import Any
+
 class SlumberBaseException(Exception): ...
 
 class SlumberHttpBaseException(SlumberBaseException):
-    def __init__(self, *args, **kwargs) -> None: ...
+    def __init__(self, *args: Any, **kwargs: Any) -> None: ...
 
 class HttpClientError(SlumberHttpBaseException): ...
 class HttpNotFoundError(HttpClientError): ...
diff --git a/stubs/slumber/slumber/serialize.pyi b/stubs/slumber/slumber/serialize.pyi
index a3cb19796..b9256756a 100644
--- a/stubs/slumber/slumber/serialize.pyi
+++ b/stubs/slumber/slumber/serialize.pyi
@@ -1,29 +1,28 @@
 from typing import Any
+from typing_extensions import TypeAlias
+
+_Data: TypeAlias = str | bytes | bytearray
 
 class BaseSerializer:
-    content_types: Any
-    key: Any
-    def get_content_type(self): ...
-    def loads(self, data) -> None: ...
-    def dumps(self, data) -> None: ...
+    content_types: list[str] | None
+    key: str | None
+    def get_content_type(self) -> str: ...
+    def loads(self, data: _Data) -> Any: ...
+    def dumps(self, data: _Data) -> Any: ...
 
 class JsonSerializer(BaseSerializer):
-    content_types: Any
+    content_types: list[str]
     key: str
-    def loads(self, data): ...
-    def dumps(self, data): ...
 
 class YamlSerializer(BaseSerializer):
-    content_types: Any
+    content_types: list[str]
     key: str
-    def loads(self, data): ...
-    def dumps(self, data): ...
 
 class Serializer:
-    serializers: Any
-    default: Any
-    def __init__(self, default: Any | None = ..., serializers: Any | None = ...) -> None: ...
-    def get_serializer(self, name: Any | None = ..., content_type: Any | None = ...): ...
-    def loads(self, data, format: Any | None = ...): ...
-    def dumps(self, data, format: Any | None = ...): ...
-    def get_content_type(self, format: Any | None = ...): ...
+    serializers: list[BaseSerializer]
+    default: str
+    def __init__(self, default: str | None = ..., serializers: list[BaseSerializer] | None = ...) -> None: ...
+    def get_serializer(self, name: str | None = ..., content_type: str | None = ...) -> BaseSerializer: ...
+    def loads(self, data: _Data, format: str | None = ...) -> Any: ...
+    def dumps(self, data: _Data, format: str | None = ...) -> Any: ...
+    def get_content_type(self, format: str | None = ...) -> str: ...
diff --git a/stubs/slumber/slumber/utils.pyi b/stubs/slumber/slumber/utils.pyi
index 818c5a39f..3dc0c9ee6 100644
--- a/stubs/slumber/slumber/utils.pyi
+++ b/stubs/slumber/slumber/utils.pyi
@@ -1,3 +1,10 @@
-def url_join(base, *args): ...
-def copy_kwargs(dictionary): ...
-def iterator(d): ...
+from collections.abc import ItemsView, Mapping, MutableMapping
+from typing import Any, TypeVar
+
+_KT = TypeVar("_KT")
+_VT_co = TypeVar("_VT_co", covariant=True)
+_MM = TypeVar("_MM", bound=MutableMapping[Any, Any])
+
+def url_join(base: str, *args: str) -> str: ...
+def copy_kwargs(dictionary: _MM) -> _MM: ...
+def iterator(d: Mapping[_KT, _VT_co]) -> ItemsView[_KT, _VT_co]: ...