> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mem0.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# LangChain

> Use LangChain as an embedding provider in Mem0 to access a wide range of models through a unified interface.

Mem0 supports LangChain as a provider to access a wide range of embedding models. LangChain is a framework for developing applications powered by language models, making it easy to integrate various embedding providers through a consistent interface.

For a complete list of available embedding models supported by LangChain, refer to the [LangChain Text Embedding documentation](https://python.langchain.com/docs/integrations/text_embedding/).

## Usage

<CodeGroup>
  ```python Python theme={null}
  import os
  from mem0 import Memory
  from langchain_openai import OpenAIEmbeddings

  # Set necessary environment variables for your chosen LangChain provider
  os.environ["OPENAI_API_KEY"] = "your-api-key"

  # Initialize a LangChain embeddings model directly
  openai_embeddings = OpenAIEmbeddings(
      model="text-embedding-3-small",
      dimensions=1536
  )

  # Pass the initialized model to the config
  config = {
      "embedder": {
          "provider": "langchain",
          "config": {
              "model": openai_embeddings
          }
      }
  }

  m = Memory.from_config(config)
  messages = [
      {"role": "user", "content": "I'm planning to watch a movie tonight. Any recommendations?"},
      {"role": "assistant", "content": "How about thriller movies? They can be quite engaging."},
      {"role": "user", "content": "I'm not a big fan of thriller movies but I love sci-fi movies."},
      {"role": "assistant", "content": "Got it! I'll avoid thriller recommendations and suggest sci-fi movies in the future."}
  ]
  m.add(messages, user_id="alice", metadata={"category": "movies"})
  ```

  ```typescript TypeScript theme={null}
  import { Memory } from 'mem0ai/oss';
  import { OpenAIEmbeddings } from "@langchain/openai";

  // Initialize a LangChain embeddings model directly
  const openaiEmbeddings = new OpenAIEmbeddings({
      modelName: "text-embedding-3-small",
      dimensions: 1536,
      apiKey: process.env.OPENAI_API_KEY,
  });

  const config = {
    embedder: {
      provider: 'langchain',
      config: {
        model: openaiEmbeddings,
      },
    },
  };

  const memory = new Memory(config);
  const messages = [
      {"role": "user", "content": "I'm planning to watch a movie tonight. Any recommendations?"},
      {"role": "assistant", "content": "How about thriller movies? They can be quite engaging."},
      {"role": "user", "content": "I'm not a big fan of thriller movies but I love sci-fi movies."},
      {"role": "assistant", "content": "Got it! I'll avoid thriller recommendations and suggest sci-fi movies in the future."}
  ]
  await memory.add(messages, { userId: "alice", metadata: { category: "movies" } });
  ```
</CodeGroup>

## Supported LangChain Embedding Providers

LangChain supports a wide range of embedding providers, including:

* OpenAI (`OpenAIEmbeddings`)
* Cohere (`CohereEmbeddings`)
* Google (`VertexAIEmbeddings`)
* Hugging Face (`HuggingFaceEmbeddings`)
* Sentence Transformers (`HuggingFaceEmbeddings`)
* Azure OpenAI (`AzureOpenAIEmbeddings`)
* Ollama (`OllamaEmbeddings`)
* Together (`TogetherEmbeddings`)
* And many more

You can use any of these model instances directly in your configuration. For a complete and up-to-date list of available embedding providers, refer to the [LangChain Text Embedding documentation](https://python.langchain.com/docs/integrations/text_embedding/).

## Provider-Specific Configuration

When using LangChain as an embedder provider, you'll need to:

1. Set the appropriate environment variables for your chosen embedding provider
2. Import and initialize the specific model class you want to use
3. Pass the initialized model instance to the config

### Examples with Different Providers

<CodeGroup>
  #### HuggingFace Embeddings

  ```python Python theme={null}
  from langchain_huggingface import HuggingFaceEmbeddings

  # Initialize a HuggingFace embeddings model
  hf_embeddings = HuggingFaceEmbeddings(
      model_name="BAAI/bge-small-en-v1.5",
      encode_kwargs={"normalize_embeddings": True}
  )

  config = {
      "embedder": {
          "provider": "langchain",
          "config": {
              "model": hf_embeddings
          }
      }
  }
  ```

  ```typescript TypeScript theme={null}
  import { Memory } from 'mem0ai/oss';
  import { HuggingFaceEmbeddings } from "@langchain/community/embeddings/hf";

  // Initialize a HuggingFace embeddings model
  const hfEmbeddings = new HuggingFaceEmbeddings({
      modelName: "BAAI/bge-small-en-v1.5",
      encode: {
          normalize_embeddings: true,
      },
  });

  const config = {
    embedder: {
      provider: 'langchain',
      config: {
        model: hfEmbeddings,
      },
    },
  };
  ```
</CodeGroup>

<CodeGroup>
  #### Ollama Embeddings

  ```python Python theme={null}
  from langchain_ollama import OllamaEmbeddings

  # Initialize an Ollama embeddings model
  ollama_embeddings = OllamaEmbeddings(
      model="nomic-embed-text"
  )

  config = {
      "embedder": {
          "provider": "langchain",
          "config": {
              "model": ollama_embeddings
          }
      }
  }
  ```

  ```typescript TypeScript theme={null}
  import { Memory } from 'mem0ai/oss';
  import { OllamaEmbeddings } from "@langchain/community/embeddings/ollama";

  // Initialize an Ollama embeddings model
  const ollamaEmbeddings = new OllamaEmbeddings({
      model: "nomic-embed-text",
      baseUrl: "http://localhost:11434", // Ollama server URL
  });

  const config = {
    embedder: {
      provider: 'langchain',
      config: {
        model: ollamaEmbeddings,
      },
    },
  };
  ```
</CodeGroup>

<Note>
  Make sure to install the necessary LangChain packages and any provider-specific dependencies.
</Note>

## Config

All available parameters for the `langchain` embedder config are present in [Master List of All Params in Config](../config).