[Usage]: When running qwen3.5-27b with vllm 0.17.0, the Deep Thinking output is under "reasoning" and not under "reasoning_content".

[AEGEGE]

Your current environment

vllm /Qwen/Qwen3.5-27B --port 40023 --host 10.0.30.105 --served-model-name local-qwen3.5-27b --tensor-parallel-size 2 --tool-call-parser=qwen3_coder --gpu-memory-utilization=0.8 --enable-auto-tool-choice --max-model-len=262144 --skip-mm-profiling --reasoning-parser=qwen3

How would you like to use vllm

When I run the request test

curl --location 'http://10.0.30.105:40023/v1/chat/completions' \
--header 'Content-Type: application/json' \
--data '{
  "model": "local-qwen3.5-27b",
  "messages": [
    {
      "role": "user",
      "content": "你好"
    }
  ],
  "stream": true
}'

then output

data: {"id":"chatcmpl-740c22ad-c984-49a4-9a78-b7bbdc69b3d2","object":"chat.completion.chunk","created":1773161262,"model":"local-qwen3.5-27b","choices":[{"index":0,"delta":{"reasoning":"Thinking"},"logprobs":null,"finish_reason":null,"token_ids":null}]}

data: {"id":"chatcmpl-740c22ad-c984-49a4-9a78-b7bbdc69b3d2","object":"chat.completion.chunk","created":1773161262,"model":"local-qwen3.5-27b","choices":[{"index":0,"delta":{"reasoning":" Process"},"logprobs":null,"finish_reason":null,"token_ids":null}]}

I expect the output to be in the following format.

data: {"id":"as-d54pngnrxn","object":"chat.completion.chunk","created":1773151016,"model":"local-qwen3.5-27b","choices":[{"index":0,"delta":{"content":null,"reasoning_content":"Thinking"},"flag":0}]}

data: {"id":"as-d54pngnrxn","object":"chat.completion.chunk","created":1773151016,"model":"local-qwen3.5-27b","choices":[{"index":0,"delta":{"content":null,"reasoning_content":" Process:\n\n"},"flag":0}]}

How do I set it up?

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