diff --git a/.castiron.stats.yml b/.castiron.stats.yml
index a75b847028..74e5a0f40a 100644
--- a/.castiron.stats.yml
+++ b/.castiron.stats.yml
@@ -1,8 +1,8 @@
 schema_version: 1
-generation_id: baa135fa-765a-4ab9-9ec1-5c9e432437ce
-openapi_spec_hash: f56829f9ec48b31ed299c5fb497984d7
-openapi_transformed_spec_hash: 400d42fb468bbe078e4f0c87c366490b
+generation_id: 021e41cf-0817-45e4-a61f-ed6fae979669
+openapi_spec_hash: 72d34e76f62e434dc0b71e0b4ac0ce8a
+openapi_transformed_spec_hash: d432497f20d18a61808b4cd56a74dd06
 config_hash: db72038ac88cdb94ae1cafef6aada78e
-codegen_sha: 17f71f06a352b4e7b5ef168c3fd4182844620954
-codegen_hash: e5f930fec1f997ea02bd1746597be5ff2a24c1917743b5bf2d4a2ee617ef8e3b
-public_codegen_sha: 249df1f919236e7aa68b460c504dafdee7c23bb1
+codegen_sha: 2f57e709a2d02130135d501497f67d2c279150a6
+codegen_hash: b5dab72c84981b6bbd1709863e017a16f1902b9aa11cd721143186487fd2787b
+public_codegen_sha: 12578924cd37047e1bff02ea0e6f90114b363d15
diff --git a/api_reference/openapi.transformed.yml b/api_reference/openapi.transformed.yml
index 81380197d8..797a0aa9d0 100644
--- a/api_reference/openapi.transformed.yml
+++ b/api_reference/openapi.transformed.yml
@@ -70237,6 +70237,11 @@ components:
           - type: string
             description: When `group_by=service_tier`, this field provides the service tier of the grouped usage result.
           - type: 'null'
+        input_cache_write_30m_tokens:
+          anyOf:
+          - type: integer
+            description: The aggregated number of input tokens written to the cache with a 30-minute retention period. May be absent or null for older responses.
+          - type: 'null'
       required:
       - object
       - input_tokens
@@ -79227,6 +79232,11 @@ components:
           - type: string
             description: When `group_by=service_tier`, this field provides the service tier of the grouped usage result.
           - type: 'null'
+        input_cache_write_30m_tokens:
+          anyOf:
+          - type: integer
+            description: The aggregated number of input tokens written to the cache with a 30-minute retention period.
+          - type: 'null'
       type: object
       required:
       - object
diff --git a/scripts/castiron/generated-files.json b/scripts/castiron/generated-files.json
index f7bd1277ee..e5b09e89e7 100644
--- a/scripts/castiron/generated-files.json
+++ b/scripts/castiron/generated-files.json
@@ -1319,7 +1319,7 @@
     },
     "src/openai/types/admin/organization/usage_audio_speeches_response.py": {
       "mode": "100644",
-      "sha256": "05e2e670a19dfb438098204920c9a3f35ee378e0af36125fd4cd3ee7429aa9e5"
+      "sha256": "c5adb8cfc3780128c64bbae6a4cdeff87f42b616c771a8284aa6196b5ed68ff6"
     },
     "src/openai/types/admin/organization/usage_audio_transcriptions_params.py": {
       "mode": "100644",
@@ -1327,7 +1327,7 @@
     },
     "src/openai/types/admin/organization/usage_audio_transcriptions_response.py": {
       "mode": "100644",
-      "sha256": "3825e0f36eb5896571dc6f73e5c457d88694e17c4f9502aa84071df084fc2b54"
+      "sha256": "7d94093feee69d6e5a9175b8cf6ba8be06c23fedf2ce6a6059ccb94792f02783"
     },
     "src/openai/types/admin/organization/usage_code_interpreter_sessions_params.py": {
       "mode": "100644",
@@ -1335,7 +1335,7 @@
     },
     "src/openai/types/admin/organization/usage_code_interpreter_sessions_response.py": {
       "mode": "100644",
-      "sha256": "91e50fc917e87b8bb86c49cfac0199fd987dbad640ed0c49f716c7b7ade7df31"
+      "sha256": "24aa79da1f2f5f69f0301e936ce8f3d2d4c9b43431b1c8ef6b77379d69527eb7"
     },
     "src/openai/types/admin/organization/usage_completions_params.py": {
       "mode": "100644",
@@ -1343,7 +1343,7 @@
     },
     "src/openai/types/admin/organization/usage_completions_response.py": {
       "mode": "100644",
-      "sha256": "5b1ae255aa4e43f3e016587b55fe06ffa961ba6a974a0909e3062d0553419b92"
+      "sha256": "ca7979c8feecb983fa7d8f3e84e8ad039d66981a09e71e3d62c555bc919ef8e6"
     },
     "src/openai/types/admin/organization/usage_costs_params.py": {
       "mode": "100644",
@@ -1351,7 +1351,7 @@
     },
     "src/openai/types/admin/organization/usage_costs_response.py": {
       "mode": "100644",
-      "sha256": "5e1be2b7f3fa9db827971109ed06fa2a6b2c0997303acae0096e95e63db168f9"
+      "sha256": "5933dcc20e7958bc3aa0462317960e17c711f048f7da4ec3f513d1ceaed7e5f3"
     },
     "src/openai/types/admin/organization/usage_decisions_params.py": {
       "mode": "100644",
@@ -1359,7 +1359,7 @@
     },
     "src/openai/types/admin/organization/usage_decisions_response.py": {
       "mode": "100644",
-      "sha256": "07bc9e3f5754e47549a938b6a03cc17c14c518d9664dc08f896c5bbeb9f95f49"
+      "sha256": "e5eac6edfa2a8950f6fc88d63bc33b3197f91567f703c1593a711e2373fa507d"
     },
     "src/openai/types/admin/organization/usage_embeddings_params.py": {
       "mode": "100644",
@@ -1367,7 +1367,7 @@
     },
     "src/openai/types/admin/organization/usage_embeddings_response.py": {
       "mode": "100644",
-      "sha256": "b7b378a194bf08d2a6fb3bf7b9b29efbd1e2b4e791d381274b6a068e3aac04b0"
+      "sha256": "30f5799ed022742399a4392e81698eb1ba8a417af67af604319c04e6899a1898"
     },
     "src/openai/types/admin/organization/usage_file_search_calls_params.py": {
       "mode": "100644",
@@ -1375,7 +1375,7 @@
     },
     "src/openai/types/admin/organization/usage_file_search_calls_response.py": {
       "mode": "100644",
-      "sha256": "01e442c497e9a5ff95dacf164620e576b2b621bc8479cc7d6db2d828064aa501"
+      "sha256": "b46f1387a0c5c0957b9db1ce64ee9c9e316903ef36c5793e08d56685e4b4a01f"
     },
     "src/openai/types/admin/organization/usage_images_params.py": {
       "mode": "100644",
@@ -1383,7 +1383,7 @@
     },
     "src/openai/types/admin/organization/usage_images_response.py": {
       "mode": "100644",
-      "sha256": "03c8cc3e73cb76c59dc19f632c3e2b16f62b57733b311e245ac0602c5d53d20a"
+      "sha256": "3657868b75ebe6d56904fc8704aaf94787d823066fc42a57637d20bde77b435e"
     },
     "src/openai/types/admin/organization/usage_moderations_params.py": {
       "mode": "100644",
@@ -1391,7 +1391,7 @@
     },
     "src/openai/types/admin/organization/usage_moderations_response.py": {
       "mode": "100644",
-      "sha256": "db407436c0c157a2355d5e5b571097cb75f80ca43303132dce051d96f2533342"
+      "sha256": "00a711f7b0fe635b1857f786c91b7d6df048299c662f9b09431b8f441c666e84"
     },
     "src/openai/types/admin/organization/usage_vector_stores_params.py": {
       "mode": "100644",
@@ -1399,7 +1399,7 @@
     },
     "src/openai/types/admin/organization/usage_vector_stores_response.py": {
       "mode": "100644",
-      "sha256": "41b4f619ae60b7b2991644334ca5d88380dc2e7b752eb5782a96da4525fec6af"
+      "sha256": "fd68d096785555fcf6528f6ddebab3c3cbe74f6f9bd097e8073dfa0e2620ad8c"
     },
     "src/openai/types/admin/organization/usage_web_search_calls_params.py": {
       "mode": "100644",
@@ -1407,7 +1407,7 @@
     },
     "src/openai/types/admin/organization/usage_web_search_calls_response.py": {
       "mode": "100644",
-      "sha256": "4c3026676d61a1951c249ad69165019dae2184fa69c63032eef5a66132637697"
+      "sha256": "1f4868a2b6e92f299173d380c1b345a90a87204bc8f0215375ad66e7f5f74be9"
     },
     "src/openai/types/admin/organization/user_delete_response.py": {
       "mode": "100644",
diff --git a/src/openai/types/admin/organization/usage_audio_speeches_response.py b/src/openai/types/admin/organization/usage_audio_speeches_response.py
index 131a1889d2..84752bb8d9 100644
--- a/src/openai/types/admin/organization/usage_audio_speeches_response.py
+++ b/src/openai/types/admin/organization/usage_audio_speeches_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_audio_transcriptions_response.py b/src/openai/types/admin/organization/usage_audio_transcriptions_response.py
index dd806c1b04..5451ac2a45 100644
--- a/src/openai/types/admin/organization/usage_audio_transcriptions_response.py
+++ b/src/openai/types/admin/organization/usage_audio_transcriptions_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_code_interpreter_sessions_response.py b/src/openai/types/admin/organization/usage_code_interpreter_sessions_response.py
index 52a29b76f3..b3b262080f 100644
--- a/src/openai/types/admin/organization/usage_code_interpreter_sessions_response.py
+++ b/src/openai/types/admin/organization/usage_code_interpreter_sessions_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_completions_response.py b/src/openai/types/admin/organization/usage_completions_response.py
index 6da6a62033..3174dcf8a3 100644
--- a/src/openai/types/admin/organization/usage_completions_response.py
+++ b/src/openai/types/admin/organization/usage_completions_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_costs_response.py b/src/openai/types/admin/organization/usage_costs_response.py
index 3f8f5ce050..317ad8035e 100644
--- a/src/openai/types/admin/organization/usage_costs_response.py
+++ b/src/openai/types/admin/organization/usage_costs_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_decisions_response.py b/src/openai/types/admin/organization/usage_decisions_response.py
index 0d8a377069..7f1cb82e8a 100644
--- a/src/openai/types/admin/organization/usage_decisions_response.py
+++ b/src/openai/types/admin/organization/usage_decisions_response.py
@@ -59,6 +59,12 @@ class DataResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_embeddings_response.py b/src/openai/types/admin/organization/usage_embeddings_response.py
index ef777ddd1e..762a612bb8 100644
--- a/src/openai/types/admin/organization/usage_embeddings_response.py
+++ b/src/openai/types/admin/organization/usage_embeddings_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_file_search_calls_response.py b/src/openai/types/admin/organization/usage_file_search_calls_response.py
index 84798a80ee..adfbbd3202 100644
--- a/src/openai/types/admin/organization/usage_file_search_calls_response.py
+++ b/src/openai/types/admin/organization/usage_file_search_calls_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_images_response.py b/src/openai/types/admin/organization/usage_images_response.py
index f84dc97fbf..237db52621 100644
--- a/src/openai/types/admin/organization/usage_images_response.py
+++ b/src/openai/types/admin/organization/usage_images_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_moderations_response.py b/src/openai/types/admin/organization/usage_moderations_response.py
index e6fd124738..806125a4cb 100644
--- a/src/openai/types/admin/organization/usage_moderations_response.py
+++ b/src/openai/types/admin/organization/usage_moderations_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_vector_stores_response.py b/src/openai/types/admin/organization/usage_vector_stores_response.py
index 85195b2cd3..f5f2b4b43b 100644
--- a/src/openai/types/admin/organization/usage_vector_stores_response.py
+++ b/src/openai/types/admin/organization/usage_vector_stores_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/src/openai/types/admin/organization/usage_web_search_calls_response.py b/src/openai/types/admin/organization/usage_web_search_calls_response.py
index 5dc60ed031..6cd8fb9ad0 100644
--- a/src/openai/types/admin/organization/usage_web_search_calls_response.py
+++ b/src/openai/types/admin/organization/usage_web_search_calls_response.py
@@ -77,6 +77,12 @@ class DataResultOrganizationUsageCompletionsResult(BaseModel):
     retention period.
     """
 
+    input_cache_write_30m_tokens: Optional[int] = None
+    """
+    The aggregated number of input tokens written to the cache with a 30-minute
+    retention period. May be absent or null for older responses.
+    """
+
     input_cache_write_tokens: Optional[int] = None
     """
     The aggregated number of input tokens written to the cache with a 30-minute
diff --git a/tests/test_usage_cache_write.py b/tests/test_usage_cache_write.py
new file mode 100644
index 0000000000..a15e425b55
--- /dev/null
+++ b/tests/test_usage_cache_write.py
@@ -0,0 +1,94 @@
+from __future__ import annotations
+
+from typing import Any, Literal
+
+import httpx2
+import pytest
+
+from openai import OpenAI, AsyncOpenAI
+from openai.types.admin.organization import UsageDecisionsResponse, UsageCompletionsResponse
+
+
+def payload(endpoint: str, value: int | None | Literal["omitted"]) -> dict[str, Any]:
+    result: dict[str, Any] = {
+        "object": f"organization.usage.{endpoint}.result",
+        "input_tokens": 200,
+        "output_tokens": 20,
+        "num_model_requests": 1,
+        "input_cache_write_tokens": 17,
+        "input_cache_write_12h_tokens": 19,
+    }
+    if value != "omitted":
+        result["input_cache_write_30m_tokens"] = value
+    return {
+        "object": "page",
+        "data": [{"object": "bucket", "start_time": 0, "end_time": 60, "results": [result]}],
+        "has_more": False,
+        "next_page": None,
+    }
+
+
+def assert_metric(response: UsageCompletionsResponse | UsageDecisionsResponse, expected: int | None) -> None:
+    result = response.data[0].results[0]
+    assert (
+        result.object == "organization.usage.completions.result"
+        or result.object == "organization.usage.decisions.result"
+    )
+    assert result.input_cache_write_30m_tokens == expected
+    assert result.input_cache_write_tokens == 17
+    assert result.input_cache_write_12h_tokens == 19
+
+
+@pytest.mark.parametrize("endpoint", ["completions", "decisions"])
+@pytest.mark.parametrize("value", [73, 0, None, "omitted"])
+def test_usage_cache_write(endpoint: str, value: int | None | Literal["omitted"]) -> None:
+    requests: list[httpx2.Request] = []
+
+    def handler(request: httpx2.Request) -> httpx2.Response:
+        requests.append(request)
+        assert request.method == "GET"
+        assert request.url.path == f"/organization/usage/{endpoint}"
+        return httpx2.Response(200, json=payload(endpoint, value))
+
+    with OpenAI(
+        api_key="fake-project-key",
+        admin_api_key="fake-admin-key",
+        base_url="https://example.test",
+        max_retries=0,
+        http_client=httpx2.Client(transport=httpx2.MockTransport(handler)),
+    ) as client:
+        response = (
+            client.admin.organization.usage.completions(start_time=0)
+            if endpoint == "completions"
+            else client.admin.organization.usage.decisions(start_time=0)
+        )
+        assert_metric(response, None if value == "omitted" else value)
+    assert len(requests) == 1
+
+
+@pytest.mark.asyncio
+@pytest.mark.parametrize("endpoint", ["completions", "decisions"])
+@pytest.mark.parametrize("value", [73, 0, None, "omitted"])
+async def test_async_usage_cache_write(endpoint: str, value: int | None | Literal["omitted"]) -> None:
+    requests: list[httpx2.Request] = []
+
+    def handler(request: httpx2.Request) -> httpx2.Response:
+        requests.append(request)
+        assert request.method == "GET"
+        assert request.url.path == f"/organization/usage/{endpoint}"
+        return httpx2.Response(200, json=payload(endpoint, value))
+
+    async with AsyncOpenAI(
+        api_key="fake-project-key",
+        admin_api_key="fake-admin-key",
+        base_url="https://example.test",
+        max_retries=0,
+        http_client=httpx2.AsyncClient(transport=httpx2.MockTransport(handler)),
+    ) as client:
+        response = (
+            await client.admin.organization.usage.completions(start_time=0)
+            if endpoint == "completions"
+            else await client.admin.organization.usage.decisions(start_time=0)
+        )
+        assert_metric(response, None if value == "omitted" else value)
+    assert len(requests) == 1