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This template makes jokes about Chuck Norris using Vertex AI PaLM2.

Environment Setup​

First, make sure you have a Google Cloud project with an active billing account, and have the gcloud CLI installed.

Configure application default credentials:

gcloud auth application-default login

To set a default Google Cloud project to use, run this command and set the project ID of the project you want to use:

gcloud config set project [PROJECT-ID]

Enable the Vertex AI API for the project:

gcloud services enable


To use this package, you should first have the LangChain CLI installed:

pip install -U langchain-cli

To create a new LangChain project and install this as the only package, you can do:

langchain app new my-app --package pirate-speak

If you want to add this to an existing project, you can just run:

langchain app add vertexai-chuck-norris

And add the following code to your file:

from vertexai_chuck_norris.chain import chain as vertexai_chuck_norris_chain

add_routes(app, vertexai_chuck_norris_chain, path="/vertexai-chuck-norris")

(Optional) Let's now configure LangSmith. LangSmith will help us trace, monitor and debug LangChain applications. You can sign up for LangSmith here. If you don't have access, you can skip this section

export LANGCHAIN_API_KEY=<your-api-key>
export LANGCHAIN_PROJECT=<your-project> # if not specified, defaults to "default"

If you are inside this directory, then you can spin up a LangServe instance directly by:

langchain serve

This will start the FastAPI app with a server is running locally at http://localhost:8000

We can see all templates at We can access the playground at

We can access the template from code with:

from langserve.client import RemoteRunnable

runnable = RemoteRunnable("http://localhost:8000/vertexai-chuck-norris")

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