deepset-ai--haystack/docs-website/versioned_docs/version-2.19/pipeline-components/generators/coheregenerator.mdx

---
title: "CohereGenerator"
id: coheregenerator
slug: "/coheregenerator"
description: "`CohereGenerator` enables text generation using Cohere's large language models (LLMs)."
---

# CohereGenerator

`CohereGenerator` enables text generation using Cohere's large language models (LLMs).

<div className="key-value-table">

|  |  |
| --- | --- |
| **Most common position in a pipeline** | After a [`PromptBuilder`](../builders/promptbuilder.mdx)  |
| **Mandatory init variables** | `api_key`: The Cohere API key. Can be set with `COHERE_API_KEY` or `CO_API_KEY` env var. |
| **Mandatory run variables** | `prompt`: A string containing the prompt for the LLM |
| **Output variables** | `replies`: A list of strings with all the replies generated by the LLM  <br /> <br />`meta`: A list of dictionaries with the metadata associated with each reply, such as token count, finish reason, and so on |
| **API reference** | [Cohere](/reference/integrations-cohere) |
| **GitHub link** | https://github.com/deepset-ai/haystack-core-integrations/tree/main/integrations/cohere |

</div>

 This integration supports Cohere models such as `command`, `command-r` and `comman-r-plus`. Check out the most recent full list in [Cohere documentation](https://docs.cohere.com/reference/chat).

## Overview

`CohereGenerator` needs a Cohere API key to work. You can write this key in:

- The `api_key` init parameter using [Secret API](../../concepts/secret-management.mdx)
- The `COHERE_API_KEY` environment variable (recommended)

Then, the component needs a prompt to operate, but you can pass any text generation parameters directly to this component using the `generation_kwargs` parameter at initialization. For more details on the parameters supported by the Cohere API, refer to the [Cohere documentation](https://docs.cohere.com/reference/chat).

### Streaming

This Generator supports [streaming](guides-to-generators/choosing-the-right-generator.mdx#streaming-support) the tokens from the LLM directly in output. To do so, pass a function to the `streaming_callback` init parameter.

## Usage

You need to install `cohere-haystack` package to use the  `CohereGenerator`:

```shell
pip install cohere-haystack
```

### On its own

Basic usage:

```python
from haystack_integrations.components.generators.cohere import CohereGenerator

client = CohereGenerator()
response = client.run("Briefly explain what NLP is in one sentence.")
print(response)

 'meta': [{'finish_reason': 'COMPLETE'}]}
```

With streaming:

```python
from haystack_integrations.components.generators.cohere import CohereGenerator

client = CohereGenerator(
    streaming_callback=lambda chunk: print(chunk.content, end="", flush=True),
)
response = client.run("Briefly explain what NLP is in one sentence.")
print(response)
```

### In a pipeline

In a RAG pipeline:

```python
from haystack import Pipeline
from haystack.components.retrievers.in_memory import InMemoryBM25Retriever
from haystack.components.builders.prompt_builder import PromptBuilder
from haystack.document_stores.in_memory import InMemoryDocumentStore
from haystack_integrations.components.generators.cohere import CohereGenerator
from haystack import Document

docstore = InMemoryDocumentStore()
docstore.write_documents(
    [
        Document(content="Rome is the capital of Italy"),
        Document(content="Paris is the capital of France"),
    ],
)

query = "What is the capital of France?"

template = """
Given the following information, answer the question.

Context:
{% for document in documents %}
    {{ document.content }}
{% endfor %}

Question: {{ query }}?
"""
pipe = Pipeline()

pipe.add_component("retriever", InMemoryBM25Retriever(document_store=docstore))
pipe.add_component("prompt_builder", PromptBuilder(template=template))
pipe.add_component("llm", CohereGenerator())
pipe.connect("retriever", "prompt_builder.documents")
pipe.connect("prompt_builder", "llm")

res = pipe.run({"prompt_builder": {"query": query}, "retriever": {"query": query}})

print(res)
```