langchain/libs/cli/README.md

langchain-cli

Install CLI

pip install -U --pre langchain-cli

Create new langchain app

langchain serve new my-app

Go into app

cd my-app

Install a package

langchain serve add extraction-summary

Install langserve

pip install "langserve[all]"

Install the langchain package

pip install -e packages/extraction-summary

Edit app/server.py to add that package to the routes

from fastapi import FastAPI
from langserve import add_routes 
from extraction_summary.chain import chain

app = FastAPI()

add_routes(app, chain)

Set env vars

export OPENAI_API_KEY=...

export LANGCHAIN_TRACING_V2=true
export LANGCHAIN_ENDPOINT="https://api.smith.langchain.com"
export LANGCHAIN_API_KEY="<your-api-key>"
export LANGCHAIN_PROJECT="extraction-summary"

Run the app

python app/server.py