# AI21 Labs

>[AI21 Labs](https://www.ai21.com/about) is a company specializing in Natural 
> Language Processing (NLP), which develops AI systems 
> that can understand and generate natural language.

This page covers how to use the `AI21` ecosystem within `LangChain`.

## Installation and Setup

- Get an AI21 api key and set it as an environment variable (`AI21_API_KEY`)
- Install the Python package:

```bash
pip install langchain-ai21
```

## LLMs

See a [usage example](/docs/integrations/llms/ai21).

### AI21 LLM

```python
from langchain_ai21 import AI21LLM
```

### AI21 Contextual Answer

You can use AI21’s contextual answers model to receive text or document, 
serving as a context, and a question and return an answer based entirely on this context.

```python
from langchain_ai21 import AI21ContextualAnswers
```


## Chat models

### AI21 Chat 

See a [usage example](/docs/integrations/chat/ai21).

```python
from langchain_ai21 import ChatAI21
```

## Embedding models

### AI21 Embeddings

See a [usage example](/docs/integrations/text_embedding/ai21).

```python
from langchain_ai21 import AI21Embeddings
```

## Text splitters

### AI21 Semantic Text Splitter

See a [usage example](/docs/integrations/document_transformers/ai21_semantic_text_splitter).

```python
from langchain_ai21 import AI21SemanticTextSplitter
```