Reducing Latency in GPT-5: Controlling Reasoning in LangChain

LangChain Academy
,
1

Hey everyone,

Does anyone know how to control or limit the reasoning depth in GPT-5 series models when using LangChain with OpenAI?

I’d like to use the latest models, but I’ve noticed that extended reasoning increases response latency. My goal is to reduce unnecessary thinking time while still maintaining good output quality.

Is there a recommended way to manage or restrict reasoning behavior when working with these models in LangChain?

Would appreciate any guidance. Thanks!

2

hi @Bitcot_Kaushal

have you tried this:

from langchain_openai import ChatOpenAI

llm = ChatOpenAI(
    model="gpt-5.2",
    use_responses_api=True,
    reasoning={"effort": "none"},  # or "low"
    verbosity="low",
    max_tokens=300,
)

from langchain_openai import ChatOpenAI

llm = ChatOpenAI(
    model="gpt-5.2",
    use_responses_api=False,
    reasoning_effort="none",  # or "minimal"/"low"
    max_tokens=300,
)

or a mix of those