# Chain-of-Note (Wikipedia)

Implements Chain-of-Note as described in https://arxiv.org/pdf/2311.09210.pdf by Yu, et al. Uses Wikipedia for retrieval.

Check out the prompt being used here https://smith.langchain.com/hub/bagatur/chain-of-note-wiki.

## Environment Setup

Uses Anthropic claude-2 chat model. Set Anthropic API key:
```bash
export ANTHROPIC_API_KEY="..."
```

## Usage

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

```shell
pip install -U "langchain-cli[serve]"
```

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

```shell
langchain app new my-app --package chain-of-note-wiki
```

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

```shell
langchain app add chain-of-note-wiki
```

And add the following code to your `server.py` file:
```python
from chain_of_note_wiki import chain as chain_of_note_wiki_chain

add_routes(app, chain_of_note_wiki_chain, path="/chain-of-note-wiki")
```

(Optional) Let's now configure LangSmith. 
LangSmith will help us trace, monitor and debug LangChain applications. 
LangSmith is currently in private beta, you can sign up [here](https://smith.langchain.com/). 
If you don't have access, you can skip this section


```shell
export LANGCHAIN_TRACING_V2=true
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:

```shell
langchain serve
```

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

We can see all templates at [http://127.0.0.1:8000/docs](http://127.0.0.1:8000/docs)
We can access the playground at [http://127.0.0.1:8000/chain-of-note-wiki/playground](http://127.0.0.1:8000/chain-of-note-wiki/playground)  

We can access the template from code with:

```python
from langserve.client import RemoteRunnable

runnable = RemoteRunnable("http://localhost:8000/chain-of-note-wiki")
```
