[Frontend] Skip stop in reasoning content

[gaocegege]

FIX #14399

FIX #14170

Skip stop checks in reasoning content. It is based on #14428 . I will rebase after it is merged.

from openai import OpenAI

# Modify OpenAI's API key and API base to use vLLM's API server.
openai_api_key = "EMPTY"
openai_api_base = "http://localhost:8000/v1"

client = OpenAI(
    api_key=openai_api_key,
    base_url=openai_api_base,
)

models = client.models.list()
model = models.data[0].id

# Round 1
messages = [{"role": "user", "content": "9.11 and 9.8, which is greater?"}]
response = client.chat.completions.create(
    model=model,
    messages=messages,
    stop="9.8",
)

reasoning_content = response.choices[0].message.reasoning_content
content = response.choices[0].message.content

print("reasoning_content for Round 1:", reasoning_content)
print("content for Round 1:", content)

Output

reasoning_content for Round 1: To determine which number is greater between 9.11 and 9.8, I'll start by aligning their decimal places.

First, I'll write 9.8 as 9.80 to have the same number of decimal places as 9.11.

Next, I'll compare the whole number parts. Both numbers have 9, so they are equal in that aspect.

Then, I'll compare the tenths place. In 9.80, the tenths digit is 8, while in 9.11, it's 1. Since 8 is greater than 1, 9.80 is greater than 9.11.

Therefore, 9.8 is the greater number.

content for Round 1: 

To determine which number is greater between **9.11** and **

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[ComposerKevin]

Very looking forward to this patch!

[gaocegege]

@ComposerKevin This is blocked by several PRs about the reasoning parser. I will try my best.

[ComposerKevin]

Could you also add an extra body option like reasoning_stop? It could be useful for manually induced thinking. For example, it will be possible to prompt model like If you're unsure about X, write $PAUSE_THINKING$ something like that.

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @gaocegege.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[gaocegege]

@aarnphm Could you please take a look?

[gaocegege]

/cc @mgoin

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @gaocegege.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[github-actions]

This pull request has been automatically marked as stale because it has not had any activity within 90 days. It will be automatically closed if no further activity occurs within 30 days. Leave a comment if you feel this pull request should remain open. Thank you!

[mgoin]

Hey @gaocegege, would you want to resolve conflicts and get this merged? Sorry for losing track

[gaocegege]

Hey, not 100% sure if it matches the design yet. I'll dig into it and catch up.

[gaocegege]

PTAL @mgoin

[gaocegege]

cc @chaunceyjiang

[chaunceyjiang]

Thanks~

[njhill]

This class is a V0 class and is obsolete.

[chaunceyjiang]

Oh I see, thanks for the reminder. Should I delete this part of the code? @njhill

[llsj14]

@gaocegege @chaunceyjiang
Just to clarify, is this PR intended only for the V0 engine and not compatible with V1? Do you have any plans to add the same feature to V1?

[chaunceyjiang]

@llsj14 Yes. #24941

[llsj14]

Thank you for letting me know!