diff --git a/githubkit/compat.py b/githubkit/compat.py
index 67b4ed47e..591c2f247 100644
--- a/githubkit/compat.py
+++ b/githubkit/compat.py
@@ -1,5 +1,6 @@
 from collections.abc import Generator
-from typing import TYPE_CHECKING, Any, Callable, Protocol, TypeVar, overload
+from typing import TYPE_CHECKING, Any, Callable, Protocol, TypeVar
+from typing_extensions import TypeForm
 
 from pydantic import VERSION
 
@@ -36,24 +37,10 @@ class GitHubModel(BaseModel):
     class ExtraGitHubModel(GitHubModel):
         model_config = ConfigDict(extra="allow")
 
-    # Remove the overload once [PEP747](https://peps.python.org/pep-0747/) is accepted
-    # We should use TypeForm here
-    @overload
-    def type_validate_python(type_: type[T], data: Any) -> T: ...
-
-    @overload
-    def type_validate_python(type_: Any, data: Any) -> Any: ...
-
-    def type_validate_python(type_: type[T], data: Any) -> T:
+    def type_validate_python(type_: TypeForm[T], data: Any) -> T:
         return TypeAdapter(type_).validate_python(data)
 
-    @overload
-    def type_validate_json(type_: type[T], data: Any) -> T: ...
-
-    @overload
-    def type_validate_json(type_: Any, data: Any) -> Any: ...
-
-    def type_validate_json(type_: type[T], data: Any) -> T:
+    def type_validate_json(type_: TypeForm[T], data: Any) -> T:
         return TypeAdapter(type_).validate_json(data)
 
     def model_dump(model: BaseModel, by_alias: bool = True) -> dict[str, Any]:
@@ -97,22 +84,10 @@ class ExtraGitHubModel(BaseModel):
         class Config:
             extra = Extra.allow
 
-    @overload
-    def type_validate_python(type_: type[T], data: Any) -> T: ...
-
-    @overload
-    def type_validate_python(type_: Any, data: Any) -> Any: ...
-
-    def type_validate_python(type_: type[T], data: Any) -> T:
+    def type_validate_python(type_: TypeForm[T], data: Any) -> T:
         return parse_obj_as(type_, data)
 
-    @overload
-    def type_validate_json(type_: type[T], data: Any) -> T: ...
-
-    @overload
-    def type_validate_json(type_: Any, data: Any) -> Any: ...
-
-    def type_validate_json(type_: type[T], data: Any) -> T:
+    def type_validate_json(type_: TypeForm[T], data: Any) -> T:
         return parse_raw_as(type_, data)
 
     def to_jsonable_python(obj: Any) -> Any:
diff --git a/githubkit/core.py b/githubkit/core.py
index 9da5cf316..954917487 100644
--- a/githubkit/core.py
+++ b/githubkit/core.py
@@ -387,12 +387,16 @@ async def _arequest(
                     raise RequestError(e) from e
 
     # check and parse response
+    def _check_is_error(self, response: httpx.Response) -> bool:
+        """Check if the response is an error."""
+        return response.is_error
+
     @overload
     def _check(
         self,
         response: httpx.Response,
         response_model: type[T],
-        error_models: Optional[Mapping[str, type]] = None,
+        error_models: Optional[Mapping[str, Any]] = None,
     ) -> Response[T]: ...
 
     @overload
@@ -400,13 +404,9 @@ def _check(
         self,
         response: httpx.Response,
         response_model: UnsetType = UNSET,
-        error_models: Optional[Mapping[str, type]] = None,
+        error_models: Optional[Mapping[str, Any]] = None,
     ) -> Response[Any]: ...
 
-    def _check_is_error(self, response: httpx.Response) -> bool:
-        """Check if the response is an error."""
-        return response.is_error
-
     def _check(
         self,
         response: httpx.Response,
diff --git a/githubkit/utils.py b/githubkit/utils.py
index 84ce5e0a2..c9c7f9c8b 100644
--- a/githubkit/utils.py
+++ b/githubkit/utils.py
@@ -1,7 +1,8 @@
 from enum import Enum
 from functools import partial
 import inspect
-from typing import Any, Generic, Literal, Optional, TypeVar, final, overload
+from typing import Any, Generic, Literal, Optional, TypeVar, final
+from typing_extensions import TypeForm
 
 from hishel._utils import generate_key
 import httpcore
@@ -98,13 +99,7 @@ def parse_query_params(params: dict[str, Any]) -> dict[str, Any]:
 class TaggedUnion(Generic[T]):
     __slots__ = ("discriminator", "tag", "type_")
 
-    @overload
-    def __init__(self, type_: type[T], discriminator: str, tag: str) -> None: ...
-
-    @overload
-    def __init__(self, type_: Any, discriminator: str, tag: str) -> None: ...
-
-    def __init__(self, type_: type[T], discriminator: str, tag: str) -> None:
+    def __init__(self, type_: TypeForm[T], discriminator: str, tag: str) -> None:
         self.type_ = type_
         self.discriminator = discriminator
         self.tag = tag
diff --git a/pyproject.toml b/pyproject.toml
index fa2b7c487..a497d1698 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -11,7 +11,7 @@ dependencies = [
   "anyio >=3.6.1, <5.0.0",
   "httpx >=0.23.0, <1.0.0",
   "hishel >=0.0.21, <=0.2.0",
-  "typing-extensions >=4.11.0, <5.0.0",
+  "typing-extensions >=4.13.0, <5.0.0",
   "pydantic >=1.9.1, <3.0.0, !=2.5.0, !=2.5.1",
 ]
 
@@ -150,6 +150,8 @@ typeCheckingMode = "standard"
 reportPrivateImportUsage = false
 reportShadowedImports = false
 disableBytesTypePromotions = true
+# enable PEP 747 `TypeForm` check
+enableExperimentalFeatures = true
 
 pythonPlatform = "All"
 defineConstant = { PYDANTIC_V2 = true }
diff --git a/uv.lock b/uv.lock
index fa35852d1..22c6ba2f2 100644
--- a/uv.lock
+++ b/uv.lock
@@ -875,7 +875,7 @@ requires-dist = [
     { name = "pyjwt", extras = ["crypto"], marker = "extra == 'auth'", specifier = ">=2.4.0,<3.0.0" },
     { name = "pyjwt", extras = ["crypto"], marker = "extra == 'auth-app'", specifier = ">=2.4.0,<3.0.0" },
     { name = "pyjwt", extras = ["crypto"], marker = "extra == 'jwt'", specifier = ">=2.4.0,<3.0.0" },
-    { name = "typing-extensions", specifier = ">=4.11.0,<5.0.0" },
+    { name = "typing-extensions", specifier = ">=4.13.0,<5.0.0" },
 ]
 provides-extras = ["jwt", "auth-app", "auth-oauth-device", "auth", "all"]