self, query: str, *, run_manager: CallbackManagerForRetrieverRun. similarity_search_with_score method in a short function that packages scores into the associated document's metadata. This notebook shows how to use the Neo4j vector index ( Neo4jVector ). from_documents () is connection_string, which is the connection str to the PostgreSQL database. langchain. The python wrapping for the extension seems to support using the operation as a method and that seemed to solve the problem. This function ensures to set variables, like query, for both prompt and retriever. Feb 12, 2024 · The PGVector class is designed to interact with a PostgreSQL database, and it uses a connection string to connect to the database. document_loaders import PyPDFLoader from langchain. 鸠挥寂【 拷绸赫:LangChain:吵蚪少判捎贷须趟犯棋蜘检赛(淀) 】冀衅LangChain悦十膝蚣苇羡争烧路,看心衣骤氢否深食崇肛慧毒舌:. You can run the following command to spin up a a postgres container with the pgvector extension: docker run --name pgvector-container -e POSTGRES_USER=langchain -e POSTGRES_PASSWORD=langchain -e POSTGRES_DB=langchain -p 6024:5432 -d pgvector/pgvector:pg16. One of the required args in PGVector. 2. from_chain_type(llm=OpenAI(), chain_type="map_reduce", retriever=docsearch. py. Overview: LCEL and its benefits. A chat history component is offered by ConversationalRetrievalChain, which is an advancement of RetriervalQAChat. Summarization with LangChain by default, is dependent of the whole text length. It’s tailored for handling high-dimensional vector data, like those produced by language models such as Llama-2. Understanding the IVFFlat Index. And add the following code to your server. Here is the code for the movie trailer agent. In this technique, each of the individual documents is first sent to the language model to get an original answer and then these answers are Mar 28, 2024 · For my RAG application, I have successfully created a Vector Database on Pinecone, and now am trying to retrieve vectors from it. Performance and scalability analysis. Dec 11, 2023 · But here's where pgvector shines, making it practical by optimizing indexing for up to 2,000 dimensions, thus tailoring your similarity search performance to be both efficient and effective. pgvectorとは. May 13, 2023 · from langchain. 123 1. One major limitation of Pgvector is its limited indexing capabilities. as_retriever() -> VectorStoreRetriever. model_name="code-bison@latest", max_output_tokens=2048, temperature=0. Aug 23, 2023 · This solution was provided in a similar issue titled Filtering retrieval with ConversationalRetrievalChain. How's everything going on your end? Based on the context provided, it seems you want to use the similarity_search_with_score() function within the as_retriever() method, and ensure that the retriever only contains the filtered documents. 3. It provides different capabilities that let users identify exact and approximate nearest neighbors. code_llm = VertexAI(. Now you know four ways to do question answering with LLMs in LangChain. similarity_search_with_score () got an unexpected Apr 2, 2023 · LLMChain-> 'text' RetrievalQA-> {'question', 'result', 'source_documents'} ConversationalRetrievalChain-> {'question', 'answer', 'source_documents'} If you are using memory with each chain type. 以下、chatGPTの回答。. Parameters. In the below example, we are using a VectorStore as the Retriever, along with a RunnableSequence to do question answering. chains import RetrievalQA from langchain. Jul 11, 2023 · I am building a question-answer app using LangChain. It introduces a dedicated data type, operators, and functions that enable efficient storage, manipulation Jan 12, 2024 · I don't use this library but I was able to get your code to execute using the libraries it seems you are using. Based on the context provided, it appears that the PGVector class in the LangChain framework does have a delete_collection method for deleting an existing collection. 生成AI: Cohere Command. It also contains supporting code for evaluation and parameter tuning. – j3ffyang. Try using the combine_docs_chain_kwargs param to pass your PROMPT. _collection. Here is the code for the movie plots vector retriever. A vector store retriever is a retriever that uses a vector store to retrieve documents. Retrieval-Based Chatbots: Retrieval-based chatbots are chatbots that generate responses by selecting pre-defined responses from a database or a set of possible responses. • The retrievers are created using the FAISS vector database with appropriate embeddings. Apr 21, 2023 · First, you can specify the chain type argument in the from_chain_type method. Retrieval QA. from langchain. May 14, 2024 · Explore how Retrieval Augmented Generation (RAG) using pgvector can enhance Large Language Models (LLMs) by providing up-to-date, factual information. - langchain-pgvector/qna. 1. 5ms, demonstrating the power of pgvector indexes. We'll use Jul 7, 2023 · As RetrievalQA is dependent of the chunk size. Speed and Efficiency. Sep 11, 2023 · In this video, we'll look at Retrieval Augmented Generation - a framework for improving the quality of LLM responses by providing relevant, supplemental context to the language-model. 📃 Retrieve Last but not least I can use PGVector to run RetrievalQA for vector search. In the realm of vector databases, pgvector emerges as a noteworthy open-source extension tailored for Postgres databases. In your case, the Embeddings instance would be your CLIP model, and the list of Document objects would contain In your case, when you set "k" as 2, the retriever will only return the top 2 most relevant documents. from_chain_type( llm=llm, chain_type="stuff", retriever=store Jun 19, 2024 · How to use embeddings retrieved from a vector database to augment LLM generation. Pgvector is designed to work seamlessly with other PostgreSQL features, including indexing and querying. yarn add. Additional Information: • I have ensured that the retriever information is correctly formatted as a dictionary. as_retriever(), return_source_documents = True) Here, return_source_documents = True, only returns the chunks from which it generated the response. LangChain:幸捎LLM胞刃QA仁灭誉要炼碌馁拇滴或(首). This project is a Question Answering application with Large Language Models (LLMs) and Amazon Aurora Postgresql using pgvector. You can build a retriever from a vectorstore using its . It’s designed to work seamlessly with other PostgreSQL features, including indexing and querying. Activate pgvector extension by logging into PostgreSQL (using psql) from a different terminal: 1. Let us discuss these in detail. 将来的にはCohereのサービスがOCIで、Vector DatabaseがOracle Database 23cで提供される予定なので、GAとなった際は Nov 5, 2023 · 以上のように、Aurora Serverless PostgreSQLのpgvectorを有効化すれば、Vector DB(Vector Store)として使用してRAGを実装出来る事が分かりました。 今回はLangChainがいろいろ良い感じに処理してくれましたが、Agents for Amazon Bedrockが始まれば同様に良い感じにやってくれる Dec 4, 2023 · Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers; Advertising & Talent Reach devs & technologists worldwide about your product, service or employer brand The code lives in an integration package called: langchain_postgres. Mar 23, 2024 · We can also delete any specific information using db. cd langchain-bedrock-demo. alternatively, I tried with MongoDB atlas it's working fine and the ingestion process is completed quickly but the problem with MongoDB is MongoDB is not open source they giving only 512mb for storing the vector. to ensure the most flexible and scalable developer experience. . Create the RetrievalQA chain using the Neo4jVector as the retriever. Faiss. Vector stores are designed to efficiently manage and index these vectors, allowing for fast similarity searches. This allows you to pass in the name of the chain type you want to use. 1. This blog delves into the limitations of LLMs, introduces the RAG approach, and offers a hands-on demo with PostgreSQL, OpenAI, and LangChain, showcasing how to build a RAG application to overcome the constraints of LLMs. It’s an approximate nearest neighbor (ANN) search method that Aug 8, 2023 · Create an instance of the Qdrant class using the from_texts method or afrom_texts method for asynchronous operation. 'Sample Question', callbacks=[handler] I am getting the following error: PineconeVectorStore. May 14, 2023 · I was using RetrievalQA. LCEL was designed from day 1 to support putting prototypes in production, with no code changes, from the simplest “prompt + LLM” chain to the most complex chains. 延博穷腻容,牛呼愿色姜捅,剩名蜗偎穆霎聪!. if there is more than 1 output keys: use the relevant output key for the chain Jan 21, 2024 · ということで、今回は以下の組み合わせでRAGを試してみました。. 8. from_chain_type, to which I had passed parameters as:-RetrievalQA. Yarn. The pgvector PostgreSQL extension helps you to store and search over machine learning-generated embeddings. from_llm(). docker run --name pgvector --rm -it -p 5432:5432 -e POSTGRES_USER=postgres -e POSTGRES_PASSWORD=postgres ankane/pgvector. As we can see our text contains around 22000 tokens with GPT3. Jun 17, 2024 · Pgvector is an open-source extension for PostgreSQL that enables storing and searching over machine learning-generated embeddings. Sep 22, 2023 · custom Retriever: pass. Vector Database: PostgreSQL (pgvector) 生成AIとVector Databaseの連携: LangChain. Aug 7, 2023 · RetrievalQA Chain with MapReduce, Reine and Map ReRank. They are important for applications that fetch data to be reasoned over as part Sep 24, 2023 · Pgvector is packaged as part of Timescale Vector, so you can also access pgvector’s HNSW and IVFFLAT indexing algorithms in your LangChain applications. py at main · mshumayl/langchain-pgvector Dec 7, 2023 · The basic steps of an RAG are: Encode the user query into a semantic vector. pyをchatGPTに解説させました。. Based on the information you provided, it seems like you're trying to use the similarity_search_with_relevance_scores function with a score_threshold of 0. To only get the source documents I subclassed RetrievalQA. In your previous code, the variables got set in retriever, but not in prompt. An application using the RAG(Retrieval Augmented Generation) approach retrieves information most relevant to the user’s request from the enterprise knowledge base or content, bundles it as context along with the user’s request as a prompt, and then sends it to the May 13, 2024 · Finally, Langchain’s RetrievalQA chain-type interfaces with the PGVector data store and the GPT-4 model to provide answers to user queries based on the stored Confluence knowledge. if the chain output has only one key memory will get the output by default. 0 を有効化して試してみます。. The ability to conveniently create database indexes from your LangChain application code makes it easy to create different indexes and compare their performance. Import Necessary Libraries May 11, 2023 · RetrievalQAを使うと良いチャットボットが簡単に作れます。. I used Blue Cheese's solution but the problem with using RetrievalQA is that it calls a combine_documents_chain which costs time and the result is discarded. 媒酬刺. がありますが、ここでは PolarDB for PostgreSQL 14 で pgvector0. (Read embedding model description below) pypdf for reading PDF documents. add_texts(texts=text_list,metadatas=metadatas) retriever = store. Jun 30, 2020 · In our last post, Evaluating QA: Metrics, Predictions, and the Null Response, we took a deep dive into how to assess the quality of a BERT-like Reader for Question Answering (QA) using the Hugging Face framework. chains import RetrievalQA qa = RetrievalQA. Mar 1, 2024 · Use the Langchain PGVector module to perform a similarity search against the stored embeddings based on the query. A vector store or vector database refers to a type of database system that specializes in storing and retrieving high-dimensional numerical vectors. 0. IVFFlat stands for Inverted File with Flat Compression. 4. This extension equips Postgres with the capability to efficiently perform vector similarity searches, a powerful technique with applications ranging from recommendation systems to Aug 21, 2023 · The {context} parameter in the prompt template or RetrievalQA refers to the search context within the vector store. https://python. We’ll handle AI as a “magic box” that we can use to build cool stuff, without going too much into the details of the AI algorithms. Oct 19, 2023 · db. For example, in the below we change the chain type to map_reduce. It supports: approximate nearest neighbor search. openai for accessing OpenAI's GPT models for vectorization. The LLM application building process involves creating embeddings, storing data, splitting and loading CSV files, performing similarity searches, and using Retrieval Augmented Generation. As usual, we'll call it: main. Knowledge base Q&A program using LangChain for retrieval-augmented prompting and PGVector as vector store. We protect your data. The format of connection_string is LangChain Vector Store Nodes. Issue: Final Answer missing Document sources when using initialize_agent RetrievalQA with Agent tool boolean flag return_direct=False returning wrong source document name Hallucinations, ignoring data in vector store and returning all documents as sources May 5, 2023 · Initial Answer: You can't pass PROMPT directly as a param on ConversationalRetrievalChain. Vector store-backed retriever. sqlalchemy for integrating PG Vector with SQLAlchemy. We add a @chain decorator to the function to create a Runnable that can be used similarly to a typical retriever. LangChain Expression Language (LCEL) LCEL is the foundation of many of LangChain's components, and is a declarative way to compose chains. vectorstores import FAISS. It's like having a superpower in your database toolkit, especially if you're already a fan of PostgreSQL and have your data neatly structured. chains import RetrievalQA #from langchain A retrieval-based question-answering chain, which integrates with a retrieval component and allows you to configure input parameters and perform question-answering tasks. js. Here is the method: Oct 16, 2023 · The RetrievalQA chain, which combines question-answering with a retrieval step. Nov 15, 2023 · We use low temperature to reduce hallucinations. Introduction. We create a ChatPromptTemplate which contains our base system prompt and an input variable for the question. To get started, we’ll be using an existing . It provides different capabilities that allows you to identify both exact and approximate nearest neighbors. Euclidean similarity and cosine similarity. In this post, we'll focus on the other component of a modern Information Retrieval-based (IR) QA system: the Retriever. 1, verbose=False, ) The next step is Feb 14, 2024 · Great to see you diving into the depths of LangChain and pgvector again. Sep 15, 2023 · In this article, we’ll explore how you can set up a PostgreSQL database with the pgvector extension and utilize it to perform vectorized searches. The RetrievalQA class should accept and handle multiple retrievers from FAISS vector database without raising any errors. Feb 13, 2024 · Based on the context provided, it appears that the PGVector class in the LangChain framework does have a delete_collection method that you can use to delete an existing collection. Jul 3, 2023 · asyncabatch_as_completed(inputs:Sequence[Input], config:Optional[Union[RunnableConfig,Sequence[RunnableConfig]]]=None, *, return_exceptions:bool=False, **kwargs:Optional[Any])→AsyncIterator[Tuple[int,Union[Output,Exception]]] ¶. Apr 22, 2024 · There is a Docker image we can use! 1. The development-specific libraries include: @types/pg: Type definitions for pg. First we instantiate a vectorstore. このコードは、質問応答 (QA)システムを実装したPythonのクラス定義です。. Vector databases typically implement one or more Approximate Nearest Neighbor (ANN) algorithms, so that one can search the database with a query vector to retrieve the closest matching database records. We will use an in-memory FAISS vectorstore: from langchain_community. Jan 4, 2024 · By turning PostgreSQL into a high-performance vector store with distance-based embedding search capabilities, pgvector allows users to explore vast textual data easily. retriever = db. Use pgvector to store, index, and access embeddings, and our Mar 25, 2023 · 「LangChain」の「RetrievalQA」を試したので、まとめました。 ・LangChain v0. VectorDBQA と RetrivalQA 「LangChain」を活用する目的の1つに、専門知識を必要とする質問応答チャットボットの作成があります。 これを行う主な方法は、「Retrieval Augmented Generation」と呼ばれる手法です。ユーザーの質問を Sep 26, 2023 · I had the same issue after upgrading langchain to a version >0. Add Tailwind CSS to the application. The exact retrieval method depends Nov 28, 2023 · Large language models (LLMs) are transforming the AI landscape with their profound grasp of human and programming languages. Oct 16, 2023 · Adding new reference for langchain pgvector import CharacterTextSplitter from langchain_community. It is designed to work seamlessly with other PostgreSQL features, including indexing and querying. See the below example with ref to your provided sample code: Jun 10, 2024 · Steps to Build a RAG Application with Real-Time Data Using PGVector and Llama 3. pgvector provides different capabilities that let users identify both exact and approximate nearest neighbors. Architecture optimizations in latest RAG Creating a retriever from a vectorstore. pnpm. from_chain_type(llm, chain_type, retriever = chroma_db. It is a lightweight wrapper around the vector store class to make it conform to the retriever interface. so I drop this idea and move on to PGVector. It uses the search methods implemented by a vector store, like similarity search and MMR, to query the texts in the vector Vector stores and retrievers. touch main. GitHub - imClumsyPanda Mar 19, 2024 · 本教程详细介绍了在 Windows 系统中安装 pgvector 扩展的两种方法:使用 Visual Studio 和使用 make 命令。它还提供了其他安装方法、先决条件、故障排除技巧和常见问题解答,帮助用户轻松安装 pgvector 并充分利用其地理数据处理功能。 Dec 21, 2023 · PgVector is an extension of PostgreSQL, a popular open-source relational database. The data is stored in the database, not in a specific directory in the file system. Though it is short I really enjoy the experience and also having scheduled time with my colleagues is amazing. In this tutorial, we’ll build a Retrieval Augmented Generation (RAG) Tool using Spring Boot, ReactJS, and PGVector. This example showcases question answering over an index. The chroma db took a very long time to ingest the huge documents. The Postgresql is May 15, 2023 · The stuff documents chain (“stuff” as in “to stuff” or “to fill”) is the most straightforward of the document chains. Vector similarity search with pgvector. Ever since the To complete the code you will need to update the movie trailer agent to: Create the Neo4jVector from the moviePlots vector index. This method call (as_retriever()) returns VectorStoreRetriever initialized from this VectorStore(db). qa = RetrievalQA. These abstractions are designed to support retrieval of data-- from (vector) databases and other sources-- for integration with LLM workflows. Following the numerous tutorials on web, I was not able to come across of extracting the page number of the relevant answer that is being genera Oct 22, 2023 · The eighth step is to create a question answering system based on information retrieval using the RetrievalQA class, which takes as input a neural language model, a type of chain and a retriever Jan 29, 2024 · " A vector database is a database that can store vectors (fixed-length lists of numbers) along with other data items. #Code Generation. Let's walk through an example. SOC2 Type 2 Certified. # response = URAPI(request) # convert response (json or xml) in to langchain Document like doc = Document(page_content="response docs") # dump all those result in array of docs and return below. It is used to retrieve documents from a Retriever and then use a QA chain to answer a question based on the retrieved documents. If you want to add this to an existing project, you can just run: langchain app add sql-pgvector. It supports these 2 Nov 17, 2023 · RetrievalQA can run with fewer lines of code thanks to VectorstoreIndexCreator, a higher-level wrapper. To create it, we use a language model and a vector database as a retriever. なぜこんなことができるのか、RetrievalQAのbase. Mar 3, 2024 · Hey there @raghuldeva!Good to see you diving into another interesting challenge with LangChain. Jul 24, 2023 · You've already written a Python script that loads embeddings from MongoDB into a numpy array, initializes a FAISS index, adds the embeddings to the index, and uses the FAISS index to perform a similarity search. py file: from sql_pgvector import chain as Mar 12, 2024 · Step 1: Set up the work directory. Dec 1, 2023 · In this example, the execution time dropped to around 0. as_retriever()) query = "What did the Neo4j is an open-source graph database with integrated support for vector similarity search. To create a new LangChain project and install this as the only package, you can do: langchain app new my-app --package sql-pgvector. This section will cover how to implement retrieval in the context of chatbots, but it's worth noting that retrieval is a very subtle and deep topic - we encourage you to explore other parts of the documentation that go into greater depth! In this blog post, we will explore how open-source technologies like PGVector from Postgresql, Embeddings, Langchain and Ollama can be leveraged to perform advanced analytics on private company data while maintaining the highest standards of data privacy and security. tsx: To execute and rebuild TypeScript efficiently. Dec 5, 2023 · The pgvector extension is a powerful tool that turns PostgreSQL into a vector database. This extension equips Postgres with the capability to efficiently perform vector similarity searches, a powerful technique with applications ranging from recommendation systems to May 3, 2023 · pgvector is an open-source extension for PostgreSQL that adds the ability to store and search over ML-generated embeddings. Essential for next-generation enterprise productivity applications… Aug 30, 2023 · Vector similarity search with pgvector. delete (ids= []). Run ainvoke in parallel on a list of inputs, yielding results as they complete. Get pre-encoded documents most similar to the user’s query. The vector store can be used to create a retriever as well. document_loaders import TextLoader. PostgreSQL でベクトル計算とベクトルデータの保存・検索をするための拡張機能(Extension)です。. Here's the method definition: This method first tries to get the collection from the database using the get_collection method. as_retriever method. 5. Use RetrievalQA chain to use those embeddings to answer the provided query. Retrieval is a common technique chatbots use to augment their responses with data outside a chat model's training data. ConversationalRetrievalChain. retrievers import TFIDFRetriever retriever = TFIDFRetriever. memory import ConversationBufferMemory from langchain import PromptTemplate from langchain. com/docs/integrations/vectorstores/pgvector. It contains algorithms that search in sets of vectors of any size, up to ones that possibly do not fit in RAM. # Create an HNSW index. It wasn't clear to me if <=> is commutative or not. npm install @langchain/openai @langchain/community. In some cases, it is the only realistic way to scale pgvector to real datasets with hundreds of thousands to even millions of Sep 15, 2023 · PGVector from LangChain as a vector database for a retrieval augmented generation (RAG) application. pip install -U langchain-cli. Now, you're looking for a way to use this script within LangChain's ConversationalRetrievalChain or RetrievalQA chain. chat_models import ChatOpenAI from langchain. It is initialized with a BaseRetriever object, which is used to retrieve relevant documents for a given question. However, with Retrieval-Augmented Generation (RAG), businesses can provide their own data to Apr 8, 2023 · Conclusion. このシステムは、質問に Jan 23, 2024 · pgvector. dotenv: A library for handling environment variables. Faiss documentation. return result_docs. In summary, load_qa_chain uses all texts and accepts multiple documents; RetrievalQA uses load_qa_chain under the hood but retrieves relevant text chunks first; VectorstoreIndexCreator is the same as RetrievalQA with a higher-level interface; ConversationalRetrievalChain is useful when you want to pass in your Nov 17, 2023 · Pgvector seems easier to use because of its familiarity with PostgreSQL. Hope you're ready for some more coding adventures! 🚀. Here is the relevant code that shows how PGVector connects to a database: Jan 18, 2024 · RunnablePassthrough function is alternative of RetrievalQA in LangChain. Hybrid search combining vector and keyword searches. For styling the app, we will be using Tailwind CSS. mkdir langchain-bedrock-demo. from_texts( ["Our client, a gentleman named Jason, has a dog whose name is Dobby", "Jason has Retrieval. OpenSearch Vector Search Edition. More on Security. Insert documents into the user’s prompt. As such it refers to the search context within the vector store, which can be used to filter or refine the search results based on specific criteria or metadata associated with the documents in the vector store. Facebook AI Similarity Search (Faiss) is a library for efficient similarity search and clustering of dense vectors. as_retriever() vector_dbqa As for the RetrievalQA class, it is a subclass of the BaseRetrievalQA class and is used for question-answering against an index. Mar 11, 2024 · In this blog, we will cover how to make an OpenAI chatbot that can be used to chat with documents using Python and PGVector (PostgreSQL). Feb 28, 2024 · pgvector: A vector similarity search library for Node. from langchain_community. Type the following in your terminal to create a new directory and a new Python file. The RetrievalQA chain uses a BaseRetriever to get relevant documents. as_retriever() matched_docs Oct 9, 2023 · 🤖. It takes a list of documents, inserts them all into a prompt and passes that prompt to an LLM. The RetrievalQA class implements two main methods: _get_docs and _aget_docs. If you set "k" as 3, it will return the top 3 most relevant documents. HIPAA Compliant. In a typical AI application trained on a vast corpus of data, the model may not have access to specific, customized data, leading to less accurate or relevant responses. This is my code for the same: llm=llm, retriever=retriever, verbose=True. Oct 16, 2023 · You can add the text and metadata as follows after creating the PGVector object: #param:text_list list format #param:metadatas dictionary format {"header": "something going on" store = PGVector( collection_name=COLLECTION_NAME, connection_string=CONNECTION_STRING, embedding_function=embeddings, ) store. That's why LLM complains the missing keys. Hello, Thank you for reaching out and providing a detailed explanation of your issue. These methods take a list of Document objects, an instance of the Embeddings class, and other optional parameters. The next step is optional but recommended. May 23, 2024 · 1. The RetrievalQAChain is a chain that combines a Retriever and a QA chain (described above). By default, Supabase products are built to work both in isolation and seamlessly together. Mar 31, 2023 · Indexing Small Datasets in pgvector. An open source Vector database for developing AI applications. Jan 28, 2024 · Specialized storage like VectorDB allows RAG training/inference over corpora with trillions of examples not feasible previously. This also enables exact Oct 21, 2023 · The RetrievalQA and VectorDBQA chains indeed use different methods to retrieve relevant documents for question answering, which could lead to different sets of documents being retrieved and thus affect the quality of the generated responses. This tutorial will familiarize you with LangChain's vector store and retriever abstractions. 詳細説明については、すでに To obtain scores from a vector store retriever, we wrap the underlying vector store's . This performance gain is for a dataset with only 800 rows, but it becomes even more apparent with bigger datasets. Update the tools to use the RetrievalQA chain. Step 1 – Installing Required Packages. We have selected Python as our programming language because it has a wide range of packages that can help us simplify our code and develop a Python AI chatbot faster. Additionally, the Weaviate class in LangChain provides the add_texts method which allows you to add texts to the vector store along with their associated metadata. xr xc ti dc kt uj ya md pe yk