> ## 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.

# Retriever integrations

> Integrate with retrievers using LangChain Python.

A [retriever](/oss/python/deepagents/retrieval#building-blocks) is an interface that returns documents given an unstructured query.
It is more general than a vector store.
A retriever does not need to be able to store documents, only to return (or retrieve) them.
Retrievers can be created from vector stores, but are also broad enough to include other sources.

Retrievers accept a string query as input and return a list of [`Document`](https://reference.langchain.com/python/langchain-core/documents/base/Document) objects as output.

Note that all [vector stores](/oss/python/integrations/vectorstores) can be cast to retrievers. Refer to the vector store [integration docs](/oss/python/integrations/vectorstores/) for available vector stores.
This page lists custom retrievers, implemented via subclassing BaseRetriever.

## Bring-your-own documents

The below retrievers allow you to index and search a custom corpus of documents.

| Retriever                                                                                | Self-host | Cloud offering | Package                                                                                                                                    |
| ---------------------------------------------------------------------------------------- | --------- | -------------- | ------------------------------------------------------------------------------------------------------------------------------------------ |
| [`AmazonKnowledgeBasesRetriever`](/oss/python/integrations/retrievers/bedrock)           | ❌         | ✅              | [`langchain-aws`](https://reference.langchain.com/python/langchain-aws/retrievers/bedrock/AmazonKnowledgeBasesRetriever)                   |
| [`ElasticsearchRetriever`](/oss/python/integrations/retrievers/elasticsearch_retriever)  | ✅         | ✅              | [`langchain-elasticsearch`](https://reference.langchain.com/python/langchain-elasticsearch/retrievers/ElasticsearchRetriever)              |
| [`MemstateRetriever`](https://memstate.ai/docs/integrations/langchain)                   | ❌         | ✅              | [`langchain-memstate`](https://pypi.org/project/langchain-memstate/)                                                                       |
| [`MengramRetriever`](https://mengram.io/docs)                                            | ✅         | ✅              | [`langchain-mengram`](https://pypi.org/project/langchain-mengram/)                                                                         |
| [`NVIDIARAGRetriever`](/oss/python/integrations/retrievers/nvidia)                       | ✅         | ❌              | [`langchain-nvidia-ai-endpoints`](https://reference.langchain.com/python/langchain-nvidia-ai-endpoints/retrievers/NVIDIARAGRetriever)      |
| [`VertexAISearchRetriever`](/oss/python/integrations/retrievers/google_vertex_ai_search) | ❌         | ✅              | [`langchain-google-community`](https://reference.langchain.com/python/langchain-google-community/vertex_ai_search/VertexAISearchRetriever) |

## External index

The below retrievers will search over an external index (e.g., constructed from Internet data or similar).

| Retriever                                                                            | Source                                                                                             | Package                                                                                                                    |
| ------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------- |
| [`ParallelSearchRetriever`](/oss/python/integrations/retrievers/parallel)            | Internet search via the [Parallel Search API](https://docs.parallel.ai/search/search-quickstart)   | [`langchain-parallel`](https://reference.langchain.com/python/langchain-parallel/retrievers/ParallelSearchRetriever)       |
| [`PerplexitySearchRetriever`](/oss/python/integrations/retrievers/perplexity_search) | Internet search via the [Perplexity Search API](https://docs.perplexity.ai/docs/search/quickstart) | [`langchain-perplexity`](https://reference.langchain.com/python/langchain-perplexity/retrievers/PerplexitySearchRetriever) |
| [`YouRetriever`](/oss/python/integrations/retrievers/you-retriever)                  | Internet search                                                                                    | [`langchain-youdotcom`](https://pypi.org/project/langchain-youdotcom/)                                                     |

## All retrievers

<div class="integration-downloads-table">
  | Retriever                                                                                        | Self-host                          | Cloud offering                     | Package                                                                                                                                    | Downloads                                                                                                                                                                                                                                                                 |
  | :----------------------------------------------------------------------------------------------- | :--------------------------------- | :--------------------------------- | :----------------------------------------------------------------------------------------------------------------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
  | [`AmazonKnowledgeBasesRetriever`](/oss/python/integrations/retrievers/bedrock)                   | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-aws`](https://reference.langchain.com/python/langchain-aws/retrievers/bedrock/AmazonKnowledgeBasesRetriever)                   | <span data-sort-value="13000000"><a href="https://pypi.org/project/langchain-aws/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-aws/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                               |
  | [`Google drive`](/oss/python/integrations/retrievers/google_drive)                               | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-google-community`](https://pypi.org/project/langchain-google-community/)                                                       | <span data-sort-value="11000000"><a href="https://pypi.org/project/langchain-google-community/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-google-community/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>     |
  | [`VertexAISearchRetriever`](/oss/python/integrations/retrievers/google_vertex_ai_search)         | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-google-community`](https://reference.langchain.com/python/langchain-google-community/vertex_ai_search/VertexAISearchRetriever) | <span data-sort-value="11000000"><a href="https://pypi.org/project/langchain-google-community/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-google-community/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>     |
  | [`Pinecone rerank`](/oss/python/integrations/retrievers/pinecone_rerank)                         | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-pinecone`](https://pypi.org/project/langchain-pinecone/)                                                                       | <span data-sort-value="1000000"><a href="https://pypi.org/project/langchain-pinecone/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-pinecone/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                      |
  | [`Cohere RAG`](/oss/python/integrations/retrievers/cohere)                                       | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-cohere`](https://pypi.org/project/langchain-cohere/)                                                                           | <span data-sort-value="936000"><a href="https://pypi.org/project/langchain-cohere/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-cohere/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                           |
  | [`Cohere reranker`](/oss/python/integrations/retrievers/cohere-reranker)                         | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-cohere`](https://pypi.org/project/langchain-cohere/)                                                                           | <span data-sort-value="936000"><a href="https://pypi.org/project/langchain-cohere/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-cohere/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                           |
  | [`NVIDIARAGRetriever`](/oss/python/integrations/retrievers/nvidia)                               | <span data-sort-value="2">✅</span> | <span data-sort-value="1">❌</span> | [`langchain-nvidia-ai-endpoints`](https://reference.langchain.com/python/langchain-nvidia-ai-endpoints/retrievers/NVIDIARAGRetriever)      | <span data-sort-value="748000"><a href="https://pypi.org/project/langchain-nvidia-ai-endpoints/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-nvidia-ai-endpoints/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span> |
  | [`WatsonxRerank`](/oss/python/integrations/retrievers/ibm_watsonx_ranker)                        | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-ibm`](https://reference.langchain.com/python/integrations/langchain_ibm/)                                                      | <span data-sort-value="674000"><a href="https://pypi.org/project/langchain-ibm/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-ibm/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                                 |
  | [`PerplexitySearchRetriever`](/oss/python/integrations/retrievers/perplexity_search)             | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-perplexity`](https://reference.langchain.com/python/langchain-perplexity/retrievers/PerplexitySearchRetriever)                 | <span data-sort-value="353000"><a href="https://pypi.org/project/langchain-perplexity/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-perplexity/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                   |
  | [`ElasticsearchRetriever`](/oss/python/integrations/retrievers/elasticsearch_retriever)          | <span data-sort-value="2">✅</span> | <span data-sort-value="2">✅</span> | [`langchain-elasticsearch`](https://reference.langchain.com/python/langchain-elasticsearch/retrievers/ElasticsearchRetriever)              | <span data-sort-value="326000"><a href="https://pypi.org/project/langchain-elasticsearch/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-elasticsearch/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>             |
  | [`Graph RAG`](/oss/python/integrations/retrievers/graph_rag)                                     | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-graph-retriever`](https://pypi.org/project/langchain-graph-retriever/)                                                         | <span data-sort-value="173000"><a href="https://pypi.org/project/langchain-graph-retriever/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-graph-retriever/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>         |
  | [`Ragatouille`](/oss/python/integrations/retrievers/ragatouille)                                 | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`ragatouille`](https://pypi.org/project/ragatouille/)                                                                                     | <span data-sort-value="48000"><a href="https://pypi.org/project/ragatouille/" target="_blank">  <img src="https://static.pepy.tech/badge/ragatouille/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                                      |
  | [`Self Querying with SAP HANA Cloud Vector Engine`](https://pypi.org/project/langchain-hana/)    | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-hana`](https://pypi.org/project/langchain-hana/)                                                                               | <span data-sort-value="35000"><a href="https://pypi.org/project/langchain-hana/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-hana/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                                |
  | [`M3Retriever`](https://github.com/skynetcmd/m3-memory/blob/main/docs/integrations/LANGCHAIN.md) | <span data-sort-value="2">✅</span> | <span data-sort-value="1">❌</span> | [`m3-memory`](https://pypi.org/project/m3-memory/)                                                                                         | <span data-sort-value="25000"><a href="https://pypi.org/project/m3-memory/" target="_blank">  <img src="https://static.pepy.tech/badge/m3-memory/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                                          |
  | [`Nebius`](https://docs.tokenfactory.nebius.com/quickstart)                                      | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-nebius`](https://pypi.org/project/langchain-nebius/)                                                                           | <span data-sort-value="5000"><a href="https://pypi.org/project/langchain-nebius/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-nebius/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                             |
  | [`ParallelSearchRetriever`](/oss/python/integrations/retrievers/parallel)                        | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-parallel`](https://reference.langchain.com/python/langchain-parallel/retrievers/ParallelSearchRetriever)                       | <span data-sort-value="5000"><a href="https://pypi.org/project/langchain-parallel/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-parallel/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                         |
  | [`LinkupSearchRetriever`](https://github.com/LinkupPlatform/langchain-linkup)                    | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-linkup`](https://pypi.org/project/langchain-linkup/)                                                                           | <span data-sort-value="4000"><a href="https://pypi.org/project/langchain-linkup/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-linkup/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                             |
  | [`Nimble Extract`](https://docs.nimbleway.com/integrations/connectors/langchain)                 | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-nimble`](https://pypi.org/project/langchain-nimble/)                                                                           | <span data-sort-value="2000"><a href="https://pypi.org/project/langchain-nimble/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-nimble/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                             |
  | [`Nimble Search`](https://docs.nimbleway.com/integrations/connectors/langchain)                  | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-nimble`](https://pypi.org/project/langchain-nimble/)                                                                           | <span data-sort-value="2000"><a href="https://pypi.org/project/langchain-nimble/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-nimble/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                             |
  | [`YouRetriever`](/oss/python/integrations/retrievers/you-retriever)                              | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-youdotcom`](https://pypi.org/project/langchain-youdotcom/)                                                                     | <span data-sort-value="1000"><a href="https://pypi.org/project/langchain-youdotcom/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-youdotcom/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                       |
  | [`PerseusVaultRetriever`](https://github.com/Perseus-Computing-LLC/langchain-perseus-vault)      | <span data-sort-value="2">✅</span> | <span data-sort-value="1">❌</span> | [`langchain-perseus-vault`](https://pypi.org/project/langchain-perseus-vault/)                                                             | <span data-sort-value="593"><a href="https://pypi.org/project/langchain-perseus-vault/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-perseus-vault/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                |
  | [`ReplyLayerRetriever`](https://replylayer.ai/docs/guides/langchain)                             | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-replylayer`](https://pypi.org/project/langchain-replylayer/)                                                                   | <span data-sort-value="560"><a href="https://pypi.org/project/langchain-replylayer/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-replylayer/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                      |
  | [`SynapRetriever`](https://www.maximem.ai/)                                                      | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`maximem-synap-langchain`](https://pypi.org/project/maximem-synap-langchain/)                                                             | <span data-sort-value="517"><a href="https://pypi.org/project/maximem-synap-langchain/" target="_blank">  <img src="https://static.pepy.tech/badge/maximem-synap-langchain/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                |
  | [`Sourcey`](https://sourcey.com/docs/guides/guide-langchain-retriever)                           | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-sourcey`](https://pypi.org/project/langchain-sourcey/)                                                                         | <span data-sort-value="378"><a href="https://pypi.org/project/langchain-sourcey/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-sourcey/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                            |
  | [`Contextual AI reranker`](https://docs.contextual.ai/)                                          | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-contextual`](https://pypi.org/project/langchain-contextual/)                                                                   | <span data-sort-value="362"><a href="https://pypi.org/project/langchain-contextual/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-contextual/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                      |
  | [`Valyucontext`](https://docs.valyu.ai/overview)                                                 | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-valyu`](https://pypi.org/project/langchain-valyu/)                                                                             | <span data-sort-value="355"><a href="https://pypi.org/project/langchain-valyu/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-valyu/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                                |
  | [`BoxRetriever`](/oss/python/integrations/retrievers/box)                                        | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-box`](https://pypi.org/project/langchain-box/)                                                                                 | <span data-sort-value="349"><a href="https://pypi.org/project/langchain-box/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-box/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                                    |
  | [`Dappier`](https://docs.dappier.com/)                                                           | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-dappier`](https://pypi.org/project/langchain-dappier/)                                                                         | <span data-sort-value="314"><a href="https://pypi.org/project/langchain-dappier/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-dappier/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                            |
  | [`MemstateRetriever`](https://memstate.ai/docs/integrations/langchain)                           | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-memstate`](https://pypi.org/project/langchain-memstate/)                                                                       | <span data-sort-value="281"><a href="https://pypi.org/project/langchain-memstate/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-memstate/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                          |
  | [`SpiceDB Retriever`](https://github.com/authzed/langchain-spicedb)                              | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-spicedb`](https://pypi.org/project/langchain-spicedb/)                                                                         | <span data-sort-value="248"><a href="https://pypi.org/project/langchain-spicedb/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-spicedb/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                            |
  | [`Kinetica vectorstore based retriever`](https://github.com/kineticadb/langchain-kinetica)       | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-kinetica`](https://pypi.org/project/langchain-kinetica/)                                                                       | <span data-sort-value="244"><a href="https://pypi.org/project/langchain-kinetica/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-kinetica/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                          |
  | [`HighSNRDocumentCompressor`](https://www.high-snr.com/docs.html)                                | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-highsnr`](https://pypi.org/project/langchain-highsnr/)                                                                         | <span data-sort-value="237"><a href="https://pypi.org/project/langchain-highsnr/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-highsnr/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                            |
  | [`Galaxia`](https://smabbler.gitbook.io/smabbler/api-rag/smabblers-api-rag)                      | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-galaxia-retriever`](https://pypi.org/project/langchain-galaxia-retriever/)                                                     | <span data-sort-value="207"><a href="https://pypi.org/project/langchain-galaxia-retriever/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-galaxia-retriever/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>        |
  | [`Permit`](https://docs.permit.io/)                                                              | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-permit`](https://pypi.org/project/langchain-permit/)                                                                           | <span data-sort-value="206"><a href="https://pypi.org/project/langchain-permit/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-permit/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                              |
  | [`EgnyteRetriever`](/oss/python/integrations/retrievers/egnyte)                                  | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`egnyte-langchain-connector`](https://pypi.org/project/egnyte-langchain-connector/)                                                       | <span data-sort-value="202"><a href="https://pypi.org/project/egnyte-langchain-connector/" target="_blank">  <img src="https://static.pepy.tech/badge/egnyte-langchain-connector/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>          |
  | [`VectorizeRetriever`](https://docs.vectorize.io/rag-pipelines/retrieval-endpoint#access-tokens) | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-vectorize`](https://pypi.org/project/langchain-vectorize/)                                                                     | <span data-sort-value="184"><a href="https://pypi.org/project/langchain-vectorize/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-vectorize/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                        |
  | [`Cognee`](https://docs.cognee.ai/)                                                              | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-cognee`](https://pypi.org/project/langchain-cognee/)                                                                           | <span data-sort-value="173"><a href="https://pypi.org/project/langchain-cognee/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-cognee/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                              |
  | [`AgentMail`](https://github.com/agentmail-to/langchain-agentmail)                               | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-agentmail`](https://pypi.org/project/langchain-agentmail/)                                                                     | <span data-sort-value="158"><a href="https://pypi.org/project/langchain-agentmail/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-agentmail/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                        |
  | [`EngramRetriever`](https://engram.ai/)                                                          | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-engram`](https://pypi.org/project/langchain-engram/)                                                                           | <span data-sort-value="137"><a href="https://pypi.org/project/langchain-engram/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-engram/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                              |
  | [`Zotero`](https://github.com/TimBMK/langchain-zotero-retriever)                                 | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-zotero-retriever`](https://pypi.org/project/langchain-zotero-retriever/)                                                       | <span data-sort-value="134"><a href="https://pypi.org/project/langchain-zotero-retriever/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-zotero-retriever/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>          |
  | [`Greennode`](https://greennode.ai/)                                                             | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-greennode`](https://pypi.org/project/langchain-greennode/)                                                                     | <span data-sort-value="120"><a href="https://pypi.org/project/langchain-greennode/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-greennode/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                        |
  | [`Perigon`](https://perigon.io/docs/api/intro)                                                   | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-perigon`](https://pypi.org/project/langchain-perigon/)                                                                         | <span data-sort-value="110"><a href="https://pypi.org/project/langchain-perigon/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-perigon/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                            |
  | [`IMAP`](https://github.com/jfouret/langchain-imap)                                              | <span data-sort-value="0" />       | <span data-sort-value="0" />       | [`langchain-imap`](https://pypi.org/project/langchain-imap/)                                                                               | <span data-sort-value="105"><a href="https://pypi.org/project/langchain-imap/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-imap/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                                  |
  | [`AxioraRetriever`](https://axiora.dev/docs)                                                     | <span data-sort-value="1">❌</span> | <span data-sort-value="2">✅</span> | [`langchain-axiora`](https://pypi.org/project/langchain-axiora/)                                                                           | <span data-sort-value="60"><a href="https://pypi.org/project/langchain-axiora/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-axiora/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                               |
  | [`MengramRetriever`](https://mengram.io/docs)                                                    | <span data-sort-value="2">✅</span> | <span data-sort-value="2">✅</span> | [`langchain-mengram`](https://pypi.org/project/langchain-mengram/)                                                                         | <span data-sort-value="50"><a href="https://pypi.org/project/langchain-mengram/" target="_blank">  <img src="https://static.pepy.tech/badge/langchain-mengram/month" alt="Downloads per month" noZoom class="rounded not-prose" /></a></span>                             |
</div>

***

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