@langchain/cohere Integration

Install and configure the @langchain/cohere package for integrating Cohere AI models with LangChain.js applications.

What This Skill Does

This skill helps you set up the @langchain/cohere package in your JavaScript/TypeScript project. It handles package installation, dependency resolution to avoid version conflicts, and provides code examples for:

Instructions

Step 1: Check Project Context

1. Verify this is a Node.js/JavaScript project by looking for `package.json`

2. Read the `package.json` to understand the current dependency structure

3. Check if `@langchain/core` or `@langchain/cohere` is already installed

Step 2: Install Dependencies

1. Install the required packages:

```bash

npm install @langchain/cohere @langchain/core

```

2. If other LangChain packages are present, add dependency resolution fields to `package.json` to ensure all packages use the same `@langchain/core` version:

- Add `resolutions` field (for yarn)

- Add `overrides` field (for npm)

- Add `pnpm.overrides` field (for pnpm)

Example structure:

```json

{

"resolutions": {

"@langchain/core": "0.3.0"

},

"overrides": {

"@langchain/core": "0.3.0"

},

"pnpm": {

"overrides": {

"@langchain/core": "0.3.0"

}

}

}

```

Step 3: Configure Environment

1. Check for `.env`, `.env.local`, or similar environment files

2. Add or verify the `COHERE_API_KEY` variable:

```

COHERE_API_KEY=your-api-key

```

3. If no env file exists, inform the user they need to set the environment variable

Step 4: Provide Implementation Examples

Offer the user code examples based on their needs:

**Chat Model Example:**

```typescript

import { HumanMessage } from "@langchain/core/messages";

import { ChatCohere } from "@langchain/cohere";

const model = new ChatCohere({

apiKey: process.env.COHERE_API_KEY,

});

const response = await model.invoke([new HumanMessage("Hello world!")]);

```

**Streaming Example:**

```typescript

import { HumanMessage } from "@langchain/core/messages";

import { ChatCohere } from "@langchain/cohere";

const model = new ChatCohere({

apiKey: process.env.COHERE_API_KEY,

});

const response = await model.stream([new HumanMessage("Hello world!")]);

```

**Embeddings Example:**

```typescript

import { CohereEmbeddings } from "@langchain/cohere";

const embeddings = new CohereEmbeddings({

apiKey: process.env.COHERE_API_KEY,

});

const res = await embeddings.embedQuery("Hello world");

```

Step 5: Verify Installation

1. After installation, check that the packages appear in `package.json` dependencies

2. Optionally run `npm list @langchain/cohere @langchain/core` to verify versions

3. Confirm the environment variable is properly configured

Important Notes

Example Usage

User: "Install @langchain/cohere for my project"

User: "Set up Cohere chat model with streaming"

User: "Add Cohere embeddings to my LangChain app"

User: "Help me integrate Cohere with LangChain"