> ## Documentation Index
> Fetch the complete documentation index at: https://docs.langchain.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Anthropic integrations

> Integrate with Anthropic using LangChain JavaScript.

All functionality related to Anthropic models.

[Anthropic](https://www.anthropic.com/) is an AI safety and research company, and is the creator of Claude.
This page covers all integrations between Anthropic models and LangChain.

## Prompting best practices

Anthropic models have several prompting best practices compared to OpenAI models.

**System Messages may only be the first message**

Anthropic models require any system messages to be the first one in your prompts.

## `ChatAnthropic`

`ChatAnthropic` is a subclass of LangChain's `ChatModel`, meaning it works best with `ChatPromptTemplate`.
You can import this wrapper with the following code:

<Tip>
  See [this section for general instructions on installing LangChain packages](/oss/javascript/langchain/install).
</Tip>

```bash npm theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
npm install @langchain/anthropic @langchain/core
```

```typescript theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
import { ChatAnthropic } from "@langchain/anthropic";
const model = new ChatAnthropic({});
```

When working with ChatModels, it is preferred that you design your prompts as `ChatPromptTemplate`s.
Here is an example below of doing that:

```typescript theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
import { ChatPromptTemplate } from "@langchain/classic/prompts";

const prompt = ChatPromptTemplate.fromMessages([
  ["system", "You are a helpful chatbot"],
  ["human", "Tell me a joke about {topic}"],
]);
```

You can then use this in a chain as follows:

```typescript theme={"theme":{"light":"catppuccin-latte","dark":"catppuccin-mocha"}}
const chain = prompt.pipe(model);
await chain.invoke({ topic: "bears" });
```

See the [chat model integration page](/oss/javascript/integrations/chat/anthropic/) for more examples, including multimodal inputs.

***

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