[Misc][OpenAI] deprecate max_tokens in favor of new max_completion_tokens field for chat completion endpoint (#9837)

benchmarks/backend_request_func.py

@@ -324,7 +324,7 @@ async def async_request_openai_chat_completions(
                 },
             ],
             "temperature": 0.0,
-            "max_tokens": request_func_input.output_len,
+            "max_completion_tokens": request_func_input.output_len,
             "stream": True,
             "ignore_eos": request_func_input.ignore_eos,
         }

docs/source/serving/run_on_sky.rst

@@ -109,7 +109,7 @@ SkyPilot can scale up the service to multiple service replicas with built-in aut
       messages:
         - role: user
           content: Hello! What is your name?
-    max_tokens: 1
+    max_completion_tokens: 1
     
 .. raw:: html
 
@@ -129,7 +129,7 @@ SkyPilot can scale up the service to multiple service replicas with built-in aut
         messages:
           - role: user
             content: Hello! What is your name?
-        max_tokens: 1
+        max_completion_tokens: 1
 
   resources:
     accelerators: {L4, A10g, A10, L40, A40, A100, A100-80GB} # We can use cheaper accelerators for 8B model.
@@ -255,7 +255,7 @@ This will scale the service up to when the QPS exceeds 2 for each replica.
         messages:
           - role: user
             content: Hello! What is your name?
-        max_tokens: 1
+        max_completion_tokens: 1
 
   resources:
     accelerators: {L4, A10g, A10, L40, A40, A100, A100-80GB} # We can use cheaper accelerators for 8B model.

examples/offline_inference_openai.md

@@ -35,8 +35,8 @@
  
  ```
  $ cat openai_example_batch.jsonl
-{"custom_id": "request-1", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are a helpful assistant."},{"role": "user", "content": "Hello world!"}],"max_tokens": 1000}}
+{"custom_id": "request-1", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are a helpful assistant."},{"role": "user", "content": "Hello world!"}],"max_completion_tokens": 1000}}
-{"custom_id": "request-2", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are an unhelpful assistant."},{"role": "user", "content": "Hello world!"}],"max_tokens": 1000}}
+{"custom_id": "request-2", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are an unhelpful assistant."},{"role": "user", "content": "Hello world!"}],"max_completion_tokens": 1000}}
  ```
  
  ### Step 2: Run the batch
@@ -94,8 +94,8 @@ To follow along with this example, you can download the example batch, or create
  
  ```
  $ cat openai_example_batch.jsonl
-{"custom_id": "request-1", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are a helpful assistant."},{"role": "user", "content": "Hello world!"}],"max_tokens": 1000}}
+{"custom_id": "request-1", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are a helpful assistant."},{"role": "user", "content": "Hello world!"}],"max_completion_tokens": 1000}}
-{"custom_id": "request-2", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are an unhelpful assistant."},{"role": "user", "content": "Hello world!"}],"max_tokens": 1000}}
+{"custom_id": "request-2", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are an unhelpful assistant."},{"role": "user", "content": "Hello world!"}],"max_completion_tokens": 1000}}
  ```
 
 Now upload your batch file to your S3 bucket.

examples/openai_api_client_for_multimodal.py

@@ -53,7 +53,7 @@ def run_text_only() -> None:
             "content": "What's the capital of France?"
         }],
         model=model,
-        max_tokens=64,
+        max_completion_tokens=64,
     )
 
     result = chat_completion.choices[0].message.content
@@ -83,7 +83,7 @@ def run_single_image() -> None:
             ],
         }],
         model=model,
-        max_tokens=64,
+        max_completion_tokens=64,
     )
 
     result = chat_completion_from_url.choices[0].message.content
@@ -109,7 +109,7 @@ def run_single_image() -> None:
             ],
         }],
         model=model,
-        max_tokens=64,
+        max_completion_tokens=64,
     )
 
     result = chat_completion_from_base64.choices[0].message.content
@@ -144,7 +144,7 @@ def run_multi_image() -> None:
             ],
         }],
         model=model,
-        max_tokens=64,
+        max_completion_tokens=64,
     )
 
     result = chat_completion_from_url.choices[0].message.content
@@ -175,7 +175,7 @@ def run_audio() -> None:
             ],
         }],
         model=model,
-        max_tokens=64,
+        max_completion_tokens=64,
     )
 
     result = chat_completion_from_url.choices[0].message.content
@@ -201,7 +201,7 @@ def run_audio() -> None:
             ],
         }],
         model=model,
-        max_tokens=64,
+        max_completion_tokens=64,
     )
 
     result = chat_completion_from_base64.choices[0].message.content

examples/openai_example_batch.jsonl

@@ -1,2 +1,2 @@
-{"custom_id": "request-1", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are a helpful assistant."},{"role": "user", "content": "Hello world!"}],"max_tokens": 1000}}
+{"custom_id": "request-1", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are a helpful assistant."},{"role": "user", "content": "Hello world!"}],"max_completion_tokens": 1000}}
-{"custom_id": "request-2", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are an unhelpful assistant."},{"role": "user", "content": "Hello world!"}],"max_tokens": 1000}}
+{"custom_id": "request-2", "method": "POST", "url": "/v1/chat/completions", "body": {"model": "meta-llama/Meta-Llama-3-8B-Instruct", "messages": [{"role": "system", "content": "You are an unhelpful assistant."},{"role": "user", "content": "Hello world!"}],"max_completion_tokens": 1000}}

requirements-common.txt

@@ -10,7 +10,7 @@ protobuf # Required by LlamaTokenizer.
 fastapi >= 0.107.0, < 0.113.0; python_version < '3.9'
 fastapi >= 0.107.0, != 0.113.*, != 0.114.0; python_version >= '3.9'
 aiohttp
-openai >= 1.40.0 # Ensure modern openai package (ensure types module present)
+openai >= 1.45.0 # Ensure modern openai package (ensure types module present and max_completion_tokens field support)
 uvicorn[standard]
 pydantic >= 2.9  # Required for fastapi >= 0.113.0
 pillow  # Required for image processing

tests/entrypoints/openai/test_audio.py

@@ -68,9 +68,10 @@ async def test_single_chat_session_audio(client: openai.AsyncOpenAI,
     }]
 
     # test single completion
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=10,
+        max_completion_tokens=10,
         logprobs=True,
         top_logprobs=5)
     assert len(chat_completion.choices) == 1
@@ -91,7 +92,7 @@ async def test_single_chat_session_audio(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
     )
     message = chat_completion.choices[0].message
     assert message.content is not None and len(message.content) >= 0
@@ -123,9 +124,10 @@ async def test_single_chat_session_audio_base64encoded(
     }]
 
     # test single completion
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=10,
+        max_completion_tokens=10,
         logprobs=True,
         top_logprobs=5)
     assert len(chat_completion.choices) == 1
@@ -146,7 +148,7 @@ async def test_single_chat_session_audio_base64encoded(
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
     )
     message = chat_completion.choices[0].message
     assert message.content is not None and len(message.content) >= 0
@@ -178,7 +180,7 @@ async def test_chat_streaming_audio(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         temperature=0.0,
     )
     output = chat_completion.choices[0].message.content
@@ -188,7 +190,7 @@ async def test_chat_streaming_audio(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         temperature=0.0,
         stream=True,
     )
@@ -242,7 +244,7 @@ async def test_multi_audio_input(client: openai.AsyncOpenAI, model_name: str,
         await client.chat.completions.create(
             model=model_name,
             messages=messages,
-            max_tokens=10,
+            max_completion_tokens=10,
             temperature=0.0,
         )
 

tests/entrypoints/openai/test_chat.py

@@ -65,9 +65,10 @@ async def test_no_logprobs_chat(client: openai.AsyncOpenAI, model_name: str):
         "content": "what is 1+1?"
     }]
 
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=5,
+        max_completion_tokens=5,
         temperature=0.0,
         logprobs=False)
 
@@ -90,9 +91,10 @@ async def test_zero_logprobs_chat(client: openai.AsyncOpenAI, model_name: str):
         "content": "what is 1+1?"
     }]
 
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=5,
+        max_completion_tokens=5,
         temperature=0.0,
         logprobs=True,
         top_logprobs=0)
@@ -117,9 +119,10 @@ async def test_some_logprobs_chat(client: openai.AsyncOpenAI, model_name: str):
         "content": "what is 1+1?"
     }]
 
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=5,
+        max_completion_tokens=5,
         temperature=0.0,
         logprobs=True,
         top_logprobs=5)
@@ -149,7 +152,7 @@ async def test_too_many_chat_logprobs(client: openai.AsyncOpenAI,
     with pytest.raises((openai.BadRequestError, openai.APIError)):
         stream = await client.chat.completions.create(model=model_name,
                                                       messages=messages,
-                                                      max_tokens=10,
+                                                      max_completion_tokens=10,
                                                       logprobs=True,
                                                       top_logprobs=21,
                                                       stream=True)
@@ -159,15 +162,16 @@ async def test_too_many_chat_logprobs(client: openai.AsyncOpenAI,
     with pytest.raises(openai.BadRequestError):
         await client.chat.completions.create(model=model_name,
                                              messages=messages,
-                                             max_tokens=10,
+                                             max_completion_tokens=10,
                                              logprobs=True,
                                              top_logprobs=30,
                                              stream=False)
 
     # the server should still work afterwards
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=10,
+        max_completion_tokens=10,
         stream=False)
     message = chat_completion.choices[0].message
     assert message.content is not None and len(message.content) >= 0
@@ -271,9 +275,10 @@ async def test_single_chat_session(client: openai.AsyncOpenAI,
     }]
 
     # test single completion
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=10,
+        max_completion_tokens=10,
         logprobs=True,
         top_logprobs=5)
     assert chat_completion.id is not None
@@ -294,7 +299,7 @@ async def test_single_chat_session(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
     )
     message = chat_completion.choices[0].message
     assert message.content is not None and len(message.content) >= 0
@@ -319,7 +324,7 @@ async def test_chat_streaming(client: openai.AsyncOpenAI, model_name: str):
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         temperature=0.0,
     )
     output = chat_completion.choices[0].message.content
@@ -329,7 +334,7 @@ async def test_chat_streaming(client: openai.AsyncOpenAI, model_name: str):
     stream = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         temperature=0.0,
         stream=True,
     )
@@ -369,7 +374,7 @@ async def test_chat_completion_stream_options(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         temperature=0.0,
         stream=True,
         stream_options={"include_usage": False})
@@ -380,7 +385,7 @@ async def test_chat_completion_stream_options(client: openai.AsyncOpenAI,
     #                                   "continuous_usage_stats": False}}
     stream = await client.chat.completions.create(model=model_name,
                                                   messages=messages,
-                                                  max_tokens=10,
+                                                  max_completion_tokens=10,
                                                   temperature=0.0,
                                                   stream=True,
                                                   stream_options={
@@ -409,7 +414,7 @@ async def test_chat_completion_stream_options(client: openai.AsyncOpenAI,
         await client.chat.completions.create(
             model=model_name,
             messages=messages,
-            max_tokens=10,
+            max_completion_tokens=10,
             temperature=0.0,
             stream=False,
             stream_options={"include_usage": None})
@@ -419,7 +424,7 @@ async def test_chat_completion_stream_options(client: openai.AsyncOpenAI,
         await client.chat.completions.create(
             model=model_name,
             messages=messages,
-            max_tokens=10,
+            max_completion_tokens=10,
             temperature=0.0,
             stream=False,
             stream_options={"include_usage": True})
@@ -429,7 +434,7 @@ async def test_chat_completion_stream_options(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         extra_body=dict(min_tokens=10),
         temperature=0.0,
         stream=True,
@@ -476,7 +481,7 @@ async def test_guided_choice_chat(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         extra_body=dict(guided_choice=sample_guided_choice,
                         guided_decoding_backend=guided_decoding_backend))
     choice1 = chat_completion.choices[0].message.content
@@ -490,7 +495,7 @@ async def test_guided_choice_chat(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         extra_body=dict(guided_choice=sample_guided_choice,
                         guided_decoding_backend=guided_decoding_backend))
     choice2 = chat_completion.choices[0].message.content
@@ -517,7 +522,7 @@ async def test_guided_json_chat(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=1000,
+        max_completion_tokens=1000,
         extra_body=dict(guided_json=sample_json_schema,
                         guided_decoding_backend=guided_decoding_backend))
     message = chat_completion.choices[0].message
@@ -535,7 +540,7 @@ async def test_guided_json_chat(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=1000,
+        max_completion_tokens=1000,
         extra_body=dict(guided_json=sample_json_schema,
                         guided_decoding_backend=guided_decoding_backend))
     message = chat_completion.choices[0].message
@@ -563,7 +568,7 @@ async def test_guided_regex_chat(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=20,
+        max_completion_tokens=20,
         extra_body=dict(guided_regex=sample_regex,
                         guided_decoding_backend=guided_decoding_backend))
     ip1 = chat_completion.choices[0].message.content
@@ -575,7 +580,7 @@ async def test_guided_regex_chat(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=20,
+        max_completion_tokens=20,
         extra_body=dict(guided_regex=sample_regex,
                         guided_decoding_backend=guided_decoding_backend))
     ip2 = chat_completion.choices[0].message.content
@@ -623,7 +628,7 @@ async def test_guided_choice_chat_logprobs(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         logprobs=True,
         top_logprobs=5,
         extra_body=dict(guided_choice=sample_guided_choice,
@@ -660,7 +665,7 @@ async def test_named_tool_use(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=1000,
+        max_completion_tokens=1000,
         tools=[{
             "type": "function",
             "function": {
@@ -694,7 +699,7 @@ async def test_named_tool_use(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         model=MODEL_NAME,
         messages=messages,
-        max_tokens=1000,
+        max_completion_tokens=1000,
         tools=[{
             "type": "function",
             "function": {
@@ -750,7 +755,7 @@ async def test_required_tool_use_not_yet_supported(
         await client.chat.completions.create(
             model=MODEL_NAME,
             messages=messages,
-            max_tokens=1000,
+            max_completion_tokens=1000,
             tools=[{
                 "type": "function",
                 "function": {
@@ -765,7 +770,7 @@ async def test_required_tool_use_not_yet_supported(
         await client.chat.completions.create(
             model=MODEL_NAME,
             messages=messages,
-            max_tokens=1000,
+            max_completion_tokens=1000,
             tools=[{
                 "type": "function",
                 "function": {
@@ -796,7 +801,7 @@ async def test_inconsistent_tool_choice_and_tools(client: openai.AsyncOpenAI,
     with pytest.raises(openai.BadRequestError):
         await client.chat.completions.create(model=MODEL_NAME,
                                              messages=messages,
-                                             max_tokens=1000,
+                                             max_completion_tokens=1000,
                                              tool_choice={
                                                  "type": "function",
                                                  "function": {
@@ -809,7 +814,7 @@ async def test_inconsistent_tool_choice_and_tools(client: openai.AsyncOpenAI,
         await client.chat.completions.create(
             model=MODEL_NAME,
             messages=messages,
-            max_tokens=1000,
+            max_completion_tokens=1000,
             tools=[{
                 "type": "function",
                 "function": {

tests/entrypoints/openai/test_vision.py

@@ -78,9 +78,10 @@ async def test_single_chat_session_image(client: openai.AsyncOpenAI,
     }]
 
     # test single completion
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=10,
+        max_completion_tokens=10,
         logprobs=True,
         top_logprobs=5)
     assert len(chat_completion.choices) == 1
@@ -101,7 +102,7 @@ async def test_single_chat_session_image(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
     )
     message = chat_completion.choices[0].message
     assert message.content is not None and len(message.content) >= 0
@@ -134,7 +135,7 @@ async def test_single_chat_session_image_beamsearch(client: openai.AsyncOpenAI,
         model=model_name,
         messages=messages,
         n=2,
-        max_tokens=10,
+        max_completion_tokens=10,
         logprobs=True,
         top_logprobs=5,
         extra_body=dict(use_beam_search=True))
@@ -169,9 +170,10 @@ async def test_single_chat_session_image_base64encoded(
     }]
 
     # test single completion
-    chat_completion = await client.chat.completions.create(model=model_name,
+    chat_completion = await client.chat.completions.create(
+        model=model_name,
         messages=messages,
-                                                           max_tokens=10,
+        max_completion_tokens=10,
         logprobs=True,
         top_logprobs=5)
     assert len(chat_completion.choices) == 1
@@ -192,7 +194,7 @@ async def test_single_chat_session_image_base64encoded(
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
     )
     message = chat_completion.choices[0].message
     assert message.content is not None and len(message.content) >= 0
@@ -226,7 +228,7 @@ async def test_single_chat_session_image_base64encoded_beamsearch(
         model=model_name,
         messages=messages,
         n=2,
-        max_tokens=10,
+        max_completion_tokens=10,
         extra_body=dict(use_beam_search=True))
     assert len(chat_completion.choices) == 2
     assert chat_completion.choices[
@@ -259,7 +261,7 @@ async def test_chat_streaming_image(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         temperature=0.0,
     )
     output = chat_completion.choices[0].message.content
@@ -269,7 +271,7 @@ async def test_chat_streaming_image(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         model=model_name,
         messages=messages,
-        max_tokens=10,
+        max_completion_tokens=10,
         temperature=0.0,
         stream=True,
     )
@@ -320,7 +322,7 @@ async def test_multi_image_input(client: openai.AsyncOpenAI, model_name: str,
             await client.chat.completions.create(
                 model=model_name,
                 messages=messages,
-                max_tokens=10,
+                max_completion_tokens=10,
                 temperature=0.0,
             )
 
@@ -337,7 +339,7 @@ async def test_multi_image_input(client: openai.AsyncOpenAI, model_name: str,
         chat_completion = await client.chat.completions.create(
             model=model_name,
             messages=messages,
-            max_tokens=10,
+            max_completion_tokens=10,
             temperature=0.0,
         )
         message = chat_completion.choices[0].message

tests/tool_use/test_chat_completions.py

@@ -18,7 +18,7 @@ async def test_chat_completion_without_tools(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         messages=ensure_system_prompt(MESSAGES_WITHOUT_TOOLS, server_config),
         temperature=0,
-        max_tokens=150,
+        max_completion_tokens=150,
         model=model_name,
         logprobs=False)
     choice = chat_completion.choices[0]
@@ -38,7 +38,7 @@ async def test_chat_completion_without_tools(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         messages=ensure_system_prompt(MESSAGES_WITHOUT_TOOLS, server_config),
         temperature=0,
-        max_tokens=150,
+        max_completion_tokens=150,
         model=model_name,
         logprobs=False,
         stream=True,
@@ -86,7 +86,7 @@ async def test_chat_completion_with_tools(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         messages=ensure_system_prompt(MESSAGES_WITHOUT_TOOLS, server_config),
         temperature=0,
-        max_tokens=150,
+        max_completion_tokens=150,
         model=model_name,
         tools=[WEATHER_TOOL],
         logprobs=False)
@@ -107,7 +107,7 @@ async def test_chat_completion_with_tools(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         messages=ensure_system_prompt(MESSAGES_WITHOUT_TOOLS, server_config),
         temperature=0,
-        max_tokens=150,
+        max_completion_tokens=150,
         model=model_name,
         logprobs=False,
         tools=[WEATHER_TOOL],

tests/tool_use/test_parallel_tool_calls.py

@@ -26,7 +26,7 @@ async def test_parallel_tool_calls(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         messages=MESSAGES_ASKING_FOR_PARALLEL_TOOLS,
         temperature=0,
-        max_tokens=200,
+        max_completion_tokens=200,
         model=model_name,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False)
@@ -63,7 +63,7 @@ async def test_parallel_tool_calls(client: openai.AsyncOpenAI,
         model=model_name,
         messages=MESSAGES_ASKING_FOR_PARALLEL_TOOLS,
         temperature=0,
-        max_tokens=200,
+        max_completion_tokens=200,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False,
         stream=True)
@@ -154,7 +154,7 @@ async def test_parallel_tool_calls_with_results(client: openai.AsyncOpenAI,
     chat_completion = await client.chat.completions.create(
         messages=MESSAGES_WITH_PARALLEL_TOOL_RESPONSE,
         temperature=0,
-        max_tokens=200,
+        max_completion_tokens=200,
         model=model_name,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False)
@@ -172,7 +172,7 @@ async def test_parallel_tool_calls_with_results(client: openai.AsyncOpenAI,
     stream = await client.chat.completions.create(
         messages=MESSAGES_WITH_PARALLEL_TOOL_RESPONSE,
         temperature=0,
-        max_tokens=200,
+        max_completion_tokens=200,
         model=model_name,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False,

tests/tool_use/test_tool_calls.py

@@ -17,7 +17,7 @@ async def test_tool_call_and_choice(client: openai.AsyncOpenAI):
     chat_completion = await client.chat.completions.create(
         messages=MESSAGES_ASKING_FOR_TOOLS,
         temperature=0,
-        max_tokens=100,
+        max_completion_tokens=100,
         model=model_name,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False)
@@ -61,7 +61,7 @@ async def test_tool_call_and_choice(client: openai.AsyncOpenAI):
         model=model_name,
         messages=MESSAGES_ASKING_FOR_TOOLS,
         temperature=0,
-        max_tokens=100,
+        max_completion_tokens=100,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False,
         stream=True)
@@ -142,7 +142,7 @@ async def test_tool_call_with_results(client: openai.AsyncOpenAI):
     chat_completion = await client.chat.completions.create(
         messages=MESSAGES_WITH_TOOL_RESPONSE,
         temperature=0,
-        max_tokens=100,
+        max_completion_tokens=100,
         model=model_name,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False)
@@ -159,7 +159,7 @@ async def test_tool_call_with_results(client: openai.AsyncOpenAI):
     stream = await client.chat.completions.create(
         messages=MESSAGES_WITH_TOOL_RESPONSE,
         temperature=0,
-        max_tokens=100,
+        max_completion_tokens=100,
         model=model_name,
         tools=[WEATHER_TOOL, SEARCH_TOOL],
         logprobs=False,

vllm/entrypoints/openai/protocol.py

@@ -159,7 +159,12 @@ class ChatCompletionRequest(OpenAIBaseModel):
     logit_bias: Optional[Dict[str, float]] = None
     logprobs: Optional[bool] = False
     top_logprobs: Optional[int] = 0
-    max_tokens: Optional[int] = None
+    # TODO(#9845): remove max_tokens when field is removed from OpenAI API
+    max_tokens: Optional[int] = Field(
+        default=None,
+        deprecated=
+        'max_tokens is deprecated in favor of the max_completion_tokens field')
+    max_completion_tokens: Optional[int] = None
     n: Optional[int] = 1
     presence_penalty: Optional[float] = 0.0
     response_format: Optional[ResponseFormat] = None
@@ -295,7 +300,8 @@ class ChatCompletionRequest(OpenAIBaseModel):
 
     def to_beam_search_params(self,
                               default_max_tokens: int) -> BeamSearchParams:
-        max_tokens = self.max_tokens
+        # TODO(#9845): remove max_tokens when field is removed from OpenAI API
+        max_tokens = self.max_completion_tokens or self.max_tokens
         if max_tokens is None:
             max_tokens = default_max_tokens
 
@@ -311,7 +317,8 @@ class ChatCompletionRequest(OpenAIBaseModel):
             include_stop_str_in_output=self.include_stop_str_in_output)
 
     def to_sampling_params(self, default_max_tokens: int) -> SamplingParams:
-        max_tokens = self.max_tokens
+        # TODO(#9845): remove max_tokens when field is removed from OpenAI API
+        max_tokens = self.max_completion_tokens or self.max_tokens
         if max_tokens is None:
             max_tokens = default_max_tokens
 

vllm/entrypoints/openai/serving_engine.py

@@ -263,20 +263,26 @@ class OpenAIServing:
             return TextTokensPrompt(prompt=input_text,
                                     prompt_token_ids=input_ids)
 
-        if request.max_tokens is None:
+        # chat completion endpoint supports max_completion_tokens
+        if isinstance(request, ChatCompletionRequest):
+            # TODO(#9845): remove max_tokens when field dropped from OpenAI API
+            max_tokens = request.max_completion_tokens or request.max_tokens
+        else:
+            max_tokens = request.max_tokens
+        if max_tokens is None:
             if token_num >= self.max_model_len:
                 raise ValueError(
                     f"This model's maximum context length is "
                     f"{self.max_model_len} tokens. However, you requested "
                     f"{token_num} tokens in the messages, "
                     f"Please reduce the length of the messages.")
-        elif token_num + request.max_tokens > self.max_model_len:
+        elif token_num + max_tokens > self.max_model_len:
             raise ValueError(
                 f"This model's maximum context length is "
                 f"{self.max_model_len} tokens. However, you requested "
-                f"{request.max_tokens + token_num} tokens "
+                f"{max_tokens + token_num} tokens "
                 f"({token_num} in the messages, "
-                f"{request.max_tokens} in the completion). "
+                f"{max_tokens} in the completion). "
                 f"Please reduce the length of the messages or completion.")
 
         return TextTokensPrompt(prompt=input_text, prompt_token_ids=input_ids)