Commit dad2b56d

@@ -25,6 +25,7 @@ from ._utils import strip_not_given as strip_not_given
 from ._utils import deepcopy_minimal as deepcopy_minimal
 from ._utils import extract_type_arg as extract_type_arg
 from ._utils import is_required_type as is_required_type
+from ._utils import get_async_library as get_async_library
 from ._utils import is_annotated_type as is_annotated_type
 from ._utils import maybe_coerce_float as maybe_coerce_float
 from ._utils import get_required_header as get_required_header

@@ -18,6 +18,8 @@ from typing import (
 from pathlib import Path
 from typing_extensions import Required, Annotated, TypeGuard, get_args, get_origin
 
+import sniffio
+
 from .._types import Headers, NotGiven, FileTypes, NotGivenOr, HeadersLike
 from .._compat import is_union as _is_union
 from .._compat import parse_date as parse_date
@@ -406,3 +408,10 @@ def get_required_header(headers: HeadersLike, header: str) -> str:
             return value
 
     raise ValueError(f"Could not find {header} header")
+
+
+def get_async_library() -> str:
+    try:
+        return sniffio.current_async_library()
+    except Exception:
+        return "false"

@@ -20,7 +20,7 @@ from ._types import (
     ProxiesTypes,
     RequestOptions,
 )
-from ._utils import is_given, is_mapping
+from ._utils import is_given, is_mapping, get_async_library
 from ._version import __version__
 from ._streaming import Stream as Stream
 from ._streaming import AsyncStream as AsyncStream
@@ -147,6 +147,7 @@ class OpenAI(SyncAPIClient):
     def default_headers(self) -> dict[str, str | Omit]:
         return {
             **super().default_headers,
+            "X-Stainless-Async": "false",
             "OpenAI-Organization": self.organization if self.organization is not None else Omit(),
             **self._custom_headers,
         }
@@ -356,6 +357,7 @@ class AsyncOpenAI(AsyncAPIClient):
     def default_headers(self) -> dict[str, str | Omit]:
         return {
             **super().default_headers,
+            "X-Stainless-Async": f"async:{get_async_library()}",
             "OpenAI-Organization": self.organization if self.organization is not None else Omit(),
             **self._custom_headers,
         }

@@ -13,6 +13,7 @@ dependencies = [
     "typing-extensions>=4.5, <5",
     "anyio>=3.5.0, <4",
     "distro>=1.7.0, <2",
+    "sniffio",
     "tqdm > 4"
 ]
 requires-python = ">= 3.7.1"