Rerankers

CohereReranker

class CohereReranker(model='rerank-english-v3.0', rank_by=None, limit=5, return_score=True, api_config=None)

Bases: BaseReranker

The CohereReranker class uses Cohere’s API to rerank documents based on an input query.

This reranker is designed to interact with Cohere’s /rerank API, requiring an API key for authentication. The key can be provided directly in the api_config dictionary or through the COHERE_API_KEY environment variable. User must obtain an API key from Cohere’s website (https://dashboard.cohere.com/). Additionally, the cohere python client must be installed with pip install cohere.

from redisvl.utils.rerank import CohereReranker

# set up the Cohere reranker with some configuration
reranker = CohereReranker(rank_by=["content"], limit=2)
# rerank raw search results based on user input/query
results = reranker.rank(
    query="your input query text here",
    docs=[
        {"content": "document 1"},
        {"content": "document 2"},
        {"content": "document 3"}
    ]
)

Initialize the CohereReranker with specified model, ranking criteria, and API configuration.

Parameters:

• model (str) – The identifier for the Cohere model used for reranking. Defaults to ‘rerank-english-v3.0’.

• rank_by (Optional[List[str]]) – Optional list of keys specifying the attributes in the documents that should be considered for ranking. None means ranking will rely on the model’s default behavior.

• limit (int) – The maximum number of results to return after reranking. Must be a positive integer.

• return_score (bool) – Whether to return scores alongside the reranked results.

• api_config (Optional[Dict], optional) – Dictionary containing the API key. Defaults to None.

Raises:

• ImportError – If the cohere library is not installed.

• ValueError – If the API key is not provided.

async arank(query, docs, **kwargs)

Rerank documents based on the provided query using the Cohere rerank API.

This method processes the user’s query and the provided documents to rerank them in a manner that is potentially more relevant to the query’s context.

Parameters:

• query (str) – The user’s search query.

• docs (Union[List[Dict[str, Any]], List[str]]) – The list of documents to be ranked, either as dictionaries or strings.

Returns:

The reranked list of documents and optionally associated scores.

Return type:

Union[Tuple[Union[List[Dict[str, Any]], List[str]], float], List[Dict[str, Any]]]

rank(query, docs, **kwargs)

Rerank documents based on the provided query using the Cohere rerank API.

This method processes the user’s query and the provided documents to rerank them in a manner that is potentially more relevant to the query’s context.

Parameters:

• query (str) – The user’s search query.

• docs (Union[List[Dict[str, Any]], List[str]]) – The list of documents to be ranked, either as dictionaries or strings.

Returns:

The reranked list of documents and optionally associated scores.

Return type:

Union[Tuple[Union[List[Dict[str, Any]], List[str]], float], List[Dict[str, Any]]]