CohereTextEmbedder
This component transforms a string into a vector that captures its semantics using a Cohere embedding model. When you perform embedding retrieval, you use this component to transform your query into a vector. Then, the embedding Retriever looks for similar or relevant documents.
Most common position in a pipeline | Before an embedding Retriever in a query/RAG pipeline |
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 | “text”: A string |
Output variables | “embedding”: A list of float numbers (vectors) “meta”: A dictionary of metadata strings |
API reference | Cohere |
GitHub link | https://github.com/deepset-ai/haystack-core-integrations/tree/main/integrations/cohere |
Overview
CohereTextEmbedder
embeds a simple string (such as a query) into a vector. For embedding lists of documents, use the use the CohereDocumentEmbedder
, which enriches the document with the computed embedding, also known as vector.
The component supports the following Cohere models:
"embed-english-v3.0"
, "embed-english-light-v3.0"
, "embed-multilingual-v3.0"
,
"embed-multilingual-light-v3.0"
, "embed-english-v2.0"
, "embed-english-light-v2.0"
,
"embed-multilingual-v2.0"
. The default model is embed-english-v2.0
. This list of all supported models can be found in Cohere’s model documentation.
To start using this integration with Haystack, install it with:
pip install cohere-haystack
The component uses a COHERE_API_KEY
or CO_API_KEY
environment variable by default. Otherwise, you can pass an API key at initialization with a Secret and Secret.from_token
static method:
embedder = CohereTextEmbedder(api_key=Secret.from_token("<your-api-key>"))
To get a Cohere API key, head over to https://cohere.com/.
Usage
On its own
Here is how you can use the component on its own. You’ll need to pass in your Cohere API key via Secret or set it as an environment variable called COHERE_API_KEY
. The examples below assume you've set the environment variable.
from haystack_integrations.components.embedders.cohere.text_embedder import CohereTextEmbedder
text_to_embed = "I love pizza!"
text_embedder = CohereTextEmbedder()
print(text_embedder.run(text_to_embed))
# {'embedding': [-0.453125, 1.2236328, 2.0058594, 0.67871094...],
# 'meta': {'api_version': {'version': '1'}, 'billed_units': {'input_tokens': 4}}}
In a pipeline
from haystack import Document
from haystack import Pipeline
from haystack.document_stores.in_memory import InMemoryDocumentStore
from haystack_integrations.components.embedders.cohere.text_embedder import CohereTextEmbedder
from haystack_integrations.components.embedders.cohere.document_embedder import CohereDocumentEmbedder
from haystack.components.retrievers.in_memory import InMemoryEmbeddingRetriever
document_store = InMemoryDocumentStore(embedding_similarity_function="cosine")
documents = [Document(content="My name is Wolfgang and I live in Berlin"),
Document(content="I saw a black horse running"),
Document(content="Germany has many big cities")]
document_embedder = CohereDocumentEmbedder()
documents_with_embeddings = document_embedder.run(documents)['documents']
document_store.write_documents(documents_with_embeddings)
query_pipeline = Pipeline()
query_pipeline.add_component("text_embedder", CohereTextEmbedder())
query_pipeline.add_component("retriever", InMemoryEmbeddingRetriever(document_store=document_store))
query_pipeline.connect("text_embedder.embedding", "retriever.query_embedding")
query = "Who lives in Berlin?"
result = query_pipeline.run({"text_embedder":{"text": query}})
print(result['retriever']['documents'][0])
# Document(id=..., content: 'My name is Wolfgang and I live in Berlin')
Updated 4 months ago
Check out the API reference in the GitHub repo or in our docs: