LangChain

pip install silvanexum langchain langchain-openai

import os
from silvanexum import Silvanexum
from langchain_openai import ChatOpenAI
from langchain_core.prompts import ChatPromptTemplate
 
sx = Silvanexum()  # reads SILVANEXUM_API_KEY
 
llm = ChatOpenAI(
    model="gpt-4.1",
    base_url=sx.gateway.openai_base_url(),          # https://api.silvanexum.com/gateway/openai/v1
    api_key=os.environ["SILVANEXUM_API_KEY"],        # your Silvanexum key, not an OpenAI key
    default_headers={"x-silvanexum-trace": "notes-summary"},  # optional: stitch a multi-hop trace
)
 
prompt = ChatPromptTemplate.from_messages([
    ("system", "You summarize research notes into three bullet points."),
    ("human", "{notes}"),
])
chain = prompt | llm
 
notes = "Long-context models reduce retrieval complexity but raise cost..."
print(chain.invoke({"notes": notes}).content)

usage = sx.gateway.usage()   # 30-day totals + recent proxied calls
print(usage.totals)