vllm/docs/source/serving/integrations/langchain.md

(serving-langchain)=

LangChain

vLLM is also available via LangChain .

To install LangChain, run

$ pip install langchain langchain_community -q

To run inference on a single or multiple GPUs, use VLLM class from langchain.

from langchain_community.llms import VLLM

llm = VLLM(model="mosaicml/mpt-7b",
           trust_remote_code=True,  # mandatory for hf models
           max_new_tokens=128,
           top_k=10,
           top_p=0.95,
           temperature=0.8,
           # tensor_parallel_size=... # for distributed inference
)

print(llm("What is the capital of France ?"))

Please refer to this Tutorial for more details.