langchain/libs/partners/ai21/README.md

langchain-ai21

This package contains the LangChain integrations for AI21 through their AI21 SDK.

Installation and Setup

• Install the AI21 partner package

pip install langchain-ai21

• Get an AI21 api key and set it as an environment variable (AI21_API_KEY)

Chat Models

This package contains the ChatAI21 class, which is the recommended way to interface with AI21 Chat models.

To use, install the requirements, and configure your environment.

export AI21_API_KEY=your-api-key

Then initialize

from langchain_core.messages import HumanMessage
from langchain_ai21.chat_models import ChatAI21

chat = ChatAI21(model="j2-ultra")
messages = [HumanMessage(content="Hello from AI21")]
chat.invoke(messages)

LLMs

You can use AI21's generative AI models as Langchain LLMs:

from langchain.prompts import PromptTemplate
from langchain_ai21 import AI21LLM

llm = AI21LLM(model="j2-ultra")

template = """Question: {question}

Answer: Let's think step by step."""
prompt = PromptTemplate.from_template(template)

chain = prompt | llm

question = "Which scientist discovered relativity?"
print(chain.invoke({"question": question}))

Embeddings

You can use AI21's embeddings models as:

Query

from langchain_ai21 import AI21Embeddings

embeddings = AI21Embeddings()
embeddings.embed_query("Hello! This is some query")

Document

from langchain_ai21 import AI21Embeddings

embeddings = AI21Embeddings()
embeddings.embed_documents(["Hello! This is document 1", "And this is document 2!"])