diff --git a/docs/my-website/docs/providers/openai.md b/docs/my-website/docs/providers/openai.md
index 1f4a1687e8b..ce03642747c 100644
--- a/docs/my-website/docs/providers/openai.md
+++ b/docs/my-website/docs/providers/openai.md
@@ -434,7 +434,56 @@ curl -X POST 'http://0.0.0.0:4000/chat/completions' \
## Getting Reasoning Content in `/chat/completions`
-GPT-5 models return reasoning content when called via the Responses API. You can call these models via the `/chat/completions` endpoint by using the `openai/responses/` prefix.
+GPT-5 models return reasoning content when called via the Responses API. You can call these models via the `/chat/completions` endpoint in two ways:
+
+**Option A — per-request prefix:** Use the `openai/responses/` model prefix.
+
+**Option B — global flag (recommended):** Set `route_all_chat_openai_to_responses = True` to automatically route all OpenAI `/chat/completions` requests through the Responses API, no model prefix needed.
+
+
+
+
+```python
+import litellm
+
+litellm.route_all_chat_openai_to_responses = True
+
+response = litellm.completion(
+ model="gpt-5.4",
+ messages=[{"role": "user", "content": "What is the capital of France?"}],
+ reasoning_effort="low",
+)
+```
+
+
+
+
+Set in your proxy config:
+```yaml
+litellm_settings:
+ route_all_chat_openai_to_responses: true
+```
+
+Then call normally — no model prefix needed:
+```bash
+curl -X POST 'http://0.0.0.0:4000/chat/completions' \
+-H 'Content-Type: application/json' \
+-H 'Authorization: Bearer sk-1234' \
+-d '{
+ "model": "gpt-5.4",
+ "messages": [{"role": "user", "content": "What is the capital of France?"}],
+ "reasoning_effort": "low"
+}'
+```
+
+
+
+
+:::note
+`route_all_chat_openai_to_responses` only applies to the `openai` provider. Azure OpenAI is unaffected. You can also set it via env var: `LITELLM_ROUTE_ALL_CHAT_OPENAI_TO_RESPONSES=true`.
+:::
+
+**Option A — per-request prefix:** You can also prefix individual model names with `openai/responses/` to route just that call through the Responses API.
diff --git a/docs/my-website/docs/proxy/config_settings.md b/docs/my-website/docs/proxy/config_settings.md
index cc9090c2de6..e7693953dbe 100644
--- a/docs/my-website/docs/proxy/config_settings.md
+++ b/docs/my-website/docs/proxy/config_settings.md
@@ -197,6 +197,7 @@ router_settings:
| key_generation_settings | object | Restricts who can generate keys. [Further docs](./virtual_keys.md#restricting-key-generation) |
| disable_add_transform_inline_image_block | boolean | For Fireworks AI models - if true, turns off the auto-add of `#transform=inline` to the url of the image_url, if the model is not a vision model. |
| use_chat_completions_url_for_anthropic_messages | boolean | If true, routes OpenAI `/v1/messages` requests through chat/completions instead of the Responses API. Can also be set via env var `LITELLM_USE_CHAT_COMPLETIONS_URL_FOR_ANTHROPIC_MESSAGES=true`. |
+| route_all_chat_openai_to_responses | boolean | If true, routes all OpenAI `/chat/completions` requests through the Responses API bridge. Recommended for OpenAI models. Can also be set via env var `LITELLM_ROUTE_ALL_CHAT_OPENAI_TO_RESPONSES=true`. |
| disable_hf_tokenizer_download | boolean | If true, it defaults to using the openai tokenizer for all models (including huggingface models). |
| enable_json_schema_validation | boolean | If true, enables json schema validation for all requests. |
| enable_key_alias_format_validation | boolean | If true, validates `key_alias` format on `/key/generate` and `/key/update`. Must be 2-255 chars, start/end with alphanumeric, only allow `a-zA-Z0-9_-/.@`. Default `false`. |
@@ -850,6 +851,7 @@ router_settings:
| LITELLM_SECRET_AWS_KMS_LITELLM_LICENSE | AWS KMS encrypted license for LiteLLM
| LITELLM_TOKEN | Access token for LiteLLM integration
| LITELLM_USE_CHAT_COMPLETIONS_URL_FOR_ANTHROPIC_MESSAGES | When set to "true", routes OpenAI /v1/messages requests through chat/completions instead of the Responses API for Anthropic models. Can also be set via `litellm_settings.use_chat_completions_url_for_anthropic_messages`
+| LITELLM_ROUTE_ALL_CHAT_OPENAI_TO_RESPONSES | When set to "true", routes all OpenAI /chat/completions requests through the Responses API bridge. Recommended for OpenAI models. Can also be set via `litellm_settings.route_all_chat_openai_to_responses`
| LITELLM_USER_AGENT | Custom user agent string for LiteLLM API requests. Used for partner telemetry attribution
| LITELLM_WORKER_STARTUP_HOOKS | Comma-separated list of `module.path:function_name` callables to run in each worker process during startup. Runs early in the worker lifecycle (before config/DB loading). Useful for re-initializing per-process state like [gflags](https://github.com/google/python-gflags). See [Worker Startup Hooks](/proxy/worker_startup_hooks) for details
| LITELLM_PRINT_STANDARD_LOGGING_PAYLOAD | If true, prints the standard logging payload to the console - useful for debugging
diff --git a/litellm/__init__.py b/litellm/__init__.py
index e45d926e8db..5e9f1a17a41 100644
--- a/litellm/__init__.py
+++ b/litellm/__init__.py
@@ -218,6 +218,9 @@ modify_params = bool(os.getenv("LITELLM_MODIFY_PARAMS", False))
use_chat_completions_url_for_anthropic_messages: bool = bool(
os.getenv("LITELLM_USE_CHAT_COMPLETIONS_URL_FOR_ANTHROPIC_MESSAGES", False)
) # When True, routes OpenAI /v1/messages requests to chat/completions instead of the Responses API
+route_all_chat_openai_to_responses: bool = (
+ os.getenv("LITELLM_ROUTE_ALL_CHAT_OPENAI_TO_RESPONSES", "false").lower() == "true"
+) # When True, routes all OpenAI /chat/completions requests through the Responses API bridge
retry = True
### AUTH ###
api_key: Optional[str] = None
diff --git a/litellm/main.py b/litellm/main.py
index eace9c630ba..14dac7a6727 100644
--- a/litellm/main.py
+++ b/litellm/main.py
@@ -939,6 +939,14 @@ def responses_api_bridge_check(
reasoning_effort: Optional[Any] = None,
) -> Tuple[dict, str]:
model_info: Dict[str, Any] = {}
+
+ # Global flag: route ALL OpenAI chat completions through Responses API.
+ # Returns early with minimal model_info; callers only inspect the "mode" key.
+ if litellm.route_all_chat_openai_to_responses and custom_llm_provider == "openai":
+ model = model.replace("responses/", "")
+ model_info["mode"] = "responses"
+ return model_info, model
+
try:
model_info = cast(
dict,
diff --git a/litellm/responses/litellm_completion_transformation/transformation.py b/litellm/responses/litellm_completion_transformation/transformation.py
index 8449620c693..0eb2b5123ff 100644
--- a/litellm/responses/litellm_completion_transformation/transformation.py
+++ b/litellm/responses/litellm_completion_transformation/transformation.py
@@ -185,8 +185,9 @@ class LiteLLMCompletionResponsesConfig:
reasoning_param = responses_api_request.get("reasoning")
if reasoning_param:
if isinstance(reasoning_param, dict):
- # reasoning can be {"effort": "low|medium|high"}
- reasoning_effort = reasoning_param.get("effort")
+ # reasoning can be {"effort": "low|medium|high", "summary": "detailed"}
+ # Preserve the full dict structure for reasoning_effort
+ reasoning_effort = reasoning_param
elif isinstance(reasoning_param, str):
# reasoning could be a string directly
reasoning_effort = reasoning_param
diff --git a/tests/test_litellm/test_main.py b/tests/test_litellm/test_main.py
index d19d1d1d756..e3386746fba 100644
--- a/tests/test_litellm/test_main.py
+++ b/tests/test_litellm/test_main.py
@@ -207,7 +207,7 @@ async def test_url_with_format_param(model, sync_mode, monkeypatch):
json_str = json_str.decode("utf-8")
print(f"type of json_str: {type(json_str)}")
-
+
# Bedrock models convert URLs to base64, while direct Anthropic models support URLs
# bedrock/invoke models use Anthropic messages API which supports URLs
if model.startswith("bedrock/invoke/"):
@@ -433,7 +433,7 @@ async def test_extra_body_with_fallback(
monkeypatch.setenv("DISABLE_AIOHTTP_TRANSPORT", "True")
# Flush cache to ensure no stale aiohttp clients are used
litellm.in_memory_llm_clients_cache.flush_cache()
-
+
# Set up test parameters
model = "openrouter/deepseek/deepseek-chat"
messages = [{"role": "user", "content": "Hello, world!"}]
@@ -466,8 +466,12 @@ async def test_extra_body_with_fallback(
"finish_reason": "stop",
}
],
- "usage": {"prompt_tokens": 9, "completion_tokens": 12, "total_tokens": 21},
- }
+ "usage": {
+ "prompt_tokens": 9,
+ "completion_tokens": 12,
+ "total_tokens": 21,
+ },
+ },
)
response = await litellm.acompletion(
@@ -480,8 +484,10 @@ async def test_extra_body_with_fallback(
# Verify the response
assert response is not None
- assert len(respx_mock.calls) > 0, "Mock was not called - check if aiohttp transport is properly disabled"
-
+ assert (
+ len(respx_mock.calls) > 0
+ ), "Mock was not called - check if aiohttp transport is properly disabled"
+
# Get the request from the mock
request: httpx.Request = respx_mock.calls[0].request
request_body = request.read()
@@ -523,35 +529,43 @@ async def test_openai_env_base(
# Configure respx mock to intercept the request
mock_route = respx_mock.post(
url__regex=r"http://localhost:12345/v1/chat/completions.*"
- ).mock(return_value=httpx.Response(
- status_code=200,
- json={
- "id": "chatcmpl-123",
- "object": "chat.completion",
- "created": 1677652288,
- "model": model,
- "choices": [
- {
- "index": 0,
- "message": {
- "role": "assistant",
- "content": "Hello from mocked response!",
- },
- "finish_reason": "stop",
- }
- ],
- "usage": {"prompt_tokens": 9, "completion_tokens": 12, "total_tokens": 21},
- }
- ))
+ ).mock(
+ return_value=httpx.Response(
+ status_code=200,
+ json={
+ "id": "chatcmpl-123",
+ "object": "chat.completion",
+ "created": 1677652288,
+ "model": model,
+ "choices": [
+ {
+ "index": 0,
+ "message": {
+ "role": "assistant",
+ "content": "Hello from mocked response!",
+ },
+ "finish_reason": "stop",
+ }
+ ],
+ "usage": {
+ "prompt_tokens": 9,
+ "completion_tokens": 12,
+ "total_tokens": 21,
+ },
+ },
+ )
+ )
try:
response = await litellm.acompletion(model=model, messages=messages)
-
+
# verify we had a response
assert response.choices[0].message.content == "Hello from mocked response!"
-
+
# Verify the mock was called
- assert mock_route.called, "Mock route was not called - request may have bypassed respx"
+ assert (
+ mock_route.called
+ ), "Mock route was not called - request may have bypassed respx"
finally:
# Clean up to avoid affecting other tests
litellm.disable_aiohttp_transport = False
@@ -622,9 +636,9 @@ def test_responses_api_bridge_check_gpt_5_4_pro():
model=model_name,
custom_llm_provider="openai",
)
- assert model_info.get("mode") == "responses", (
- f"{model_name} should have mode='responses', got '{model_info.get('mode')}'"
- )
+ assert (
+ model_info.get("mode") == "responses"
+ ), f"{model_name} should have mode='responses', got '{model_info.get('mode')}'"
def test_responses_api_bridge_check_gpt_5_4_tools_plus_reasoning_routes_to_responses():
@@ -764,6 +778,49 @@ def test_responses_api_bridge_check_handles_exception():
assert model_info["mode"] == "responses"
+def test_responses_api_bridge_check_global_flag_routes_openai():
+ """When route_all_chat_openai_to_responses is True, any OpenAI model routes to responses."""
+ from litellm.main import responses_api_bridge_check
+
+ with patch.object(litellm, "route_all_chat_openai_to_responses", True):
+ model_info, model = responses_api_bridge_check(
+ model="gpt-4o",
+ custom_llm_provider="openai",
+ )
+
+ assert model == "gpt-4o"
+ assert model_info.get("mode") == "responses"
+
+
+def test_responses_api_bridge_check_global_flag_does_not_affect_azure():
+ """route_all_chat_openai_to_responses should not affect Azure models."""
+ from litellm.main import responses_api_bridge_check
+
+ with patch.object(litellm, "route_all_chat_openai_to_responses", True):
+ with patch("litellm.main._get_model_info_helper") as mock_get_model_info:
+ mock_get_model_info.return_value = {"max_tokens": 4096}
+ model_info, model = responses_api_bridge_check(
+ model="gpt-4o",
+ custom_llm_provider="azure",
+ )
+
+ assert model_info.get("mode") != "responses"
+
+
+def test_responses_api_bridge_check_global_flag_default_false():
+ """By default, route_all_chat_openai_to_responses is False and doesn't affect routing."""
+ from litellm.main import responses_api_bridge_check
+
+ with patch("litellm.main._get_model_info_helper") as mock_get_model_info:
+ mock_get_model_info.return_value = {"max_tokens": 4096}
+ model_info, model = responses_api_bridge_check(
+ model="gpt-4o",
+ custom_llm_provider="openai",
+ )
+
+ assert model_info.get("mode") != "responses"
+
+
@pytest.mark.asyncio
async def test_async_mock_delay():
"""Use asyncio await for mock delay on acompletion"""
@@ -1487,7 +1544,7 @@ def test_anthropic_text_disable_url_suffix_env_var():
def test_image_edit_merges_headers_and_extra_headers():
from litellm.images.main import base_llm_http_handler
-
+
combined_headers = {
"x-test-header-one": "value-1",
"x-test-header-two": "value-2",