LangChain
How to use GATE/0 with LangChain
LangChain is a powerful framework for building applications with largelanguage models — supporting chains, tools, memory, agents, and more.
GATE/0 integrates seamlessly with LangChain by leveraging its support for custom API endpoints and authentication keys. This allows you to route all LLM calls through GATE/0 with minimal setup — unlocking detailed usage analytics, labeling, and cost tracking — without altering how your chains are structured.
Using GATE/0 with LangChain
Set up your OpenAI provider in GATE/0
Install LangChain and its OpenAI integration
pip install langchain langchain_openai
Configure the GATE/0 API key Set your GATE/0 API key as an environment variable:
export GATE0_API_KEY=your-gate0-api-key
Implement your agent
from langchain_openai import ChatOpenAI
import os
chat = ChatOpenAI(
openai_api_base="https://gateway.gate.io/v1", # GATE0 cloud proxy URL
openai_api_key=os.environ.get("GATE0_API_KEY"), # API key provided by GATE0
model="openai/gpt-4o", # Model name with provider prefix
default_headers={ # Custom labels
"x-gate0-label-project": "alpha-1",
"x-gate0-label-client": "frontend",
"x-gate0-label-env": "prod"
}
)
response = chat.invoke("Hello, how are you?")
print(response.content)
Explanation of the implementation
ChatOpenAI
(or other LangChain LLM wrappers) is configured with:base_url
set tohttps://gateway.gate0.io/v1
- A model name prefixed with the provider slug (e.g.,
openai/gpt-4o
instead ofgpt-4o
) - Your GATE/0 API key passed via headers or environment
- Optional
extra_headers
can be used to include custom labels for resource tracking and analytics. - All standard LangChain functionality (chains, tools, memory, etc.) works as-is — now powered by GATE/0 under the hood.