Langchain examples


Langchain examples. Use LangChain Expression Language, the protocol that LangChain is built on and which facilitates component chaining. 1: Use from_messages classmethod instead. This provides even more flexibility than using LangChain AgentExecutor as the agent runtime. LLM Chain: The most common chain. Langchain Decorators: a layer on the top of LangChain that provides syntactic sugar 🍭 for writing custom langchain prompts and chains ; FastAPI + Chroma: An Example Plugin for ChatGPT, Utilizing FastAPI, LangChain and Chroma; AilingBot: Quickly integrate applications built on Langchain into IM such as Slack, WeChat Work, Feishu, DingTalk. 4 days ago · class langchain_core. 5. Case studies and proof-of-concept examples: The documents provide examples of how LLM-powered autonomous agents can be applied in various domains, such as scientific discovery and generative agent simulations. Bases: StringPromptTemplate. 2️⃣ Followed by a few practical examples illustrating how to introduce context into the conversation via a few-shot learning approach, using Langchain and HuggingFace. predict(input="Hi there!") The Example Selector is the class responsible for doing so. 7. 1 day ago · LangChain offers several value propositions for our applications available as module components. This covers how to load PDF documents into the Document format that we use downstream. The autoreload extension is already loaded. This text splitter is the recommended one for generic text. add_example (example) Add new example to store. Files. Let's start by asking a simple question that we can get an answer to from the Llama2 model using Ollama. The nice Apr 19, 2024 · Chatbots: LangChain can be used to build chatbots that interact with users naturally. LangChain is an open source framework for building applications based on large language models (LLMs). For example, here is a prompt for RAG with LLaMA-specific tokens. Azure OpenAI Service provides REST API access to OpenAI's powerful language models including the GPT-4, GPT-3. cpp. Oct 31, 2023 · For example, you can use Cohere with LangChain. from langchain import OpenAI, ConversationChain llm = OpenAI(temperature=0) conversation = ConversationChain(llm=llm, verbose=True) conversation. A collection of apps powered by LangChain, an open-source framework for LLM applications. The next step will be to install the Langchain. %load_ext autoreload %autoreload 2. The agent itself will use chat models and tool calling. LangChain is a powerful framework that simplifies the process of building advanced language model applications. Introduction. Feb 25, 2023 · LangChain is a powerful tool that can be used to work with Large Language Models (LLMs). Chains created using LCEL benefit from an automatic implementation of stream and astream allowing streaming of the final output. Parameters. You can subscribe to these events by using the callbacks argument Jan 31, 2023 · 1️⃣ An example of using Langchain to interface to the HuggingFace inference API for a QnA chatbot. %pip install -qU langchain-text-splitters. LangSmith helps you trace and evaluate your language model applications and intelligent agents to help you move from prototype to production. 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 (we’ve seen folks successfully run LCEL chains with 100s of steps in production). On the other hand, FewShotPromptTemplate works by taking in a PromptTemplate for examples, and its output is a string. It tries to split on them in order until the chunks are small enough. Prompt templates in LangChain are predefined recipes for generating language model prompts. In this guide, we will walk through how to do for two functions: A made up search function that always returns the string “LangChain” Mar 6, 2024 · Note: In these examples, you used . - example_prompt: converts each example into 1 or more messages through its format_messages method. For example, LangChain can be used to build a chatbot that can answer client questions, provide customer assistance, and even arrange appointments. Tool-calling is extremely useful for building tool-using chains and agents, and for getting structured outputs from models more generally. These case studies serve as examples of the capabilities and potential applications of such agents. When indexing content, hashes are computed for each document, and the following information is stored in the record manager: the document hash (hash of both page content and metadata) write time. batch() accepts a list of messages that the LLM responds to in one call. base. After installing Cohere, using npm install cohere-ai , you can make a simple question-->answer code using LangChain and Cohere like this: Sep 8, 2023 · LangChain example. LangChain provides a callbacks system that allows you to hook into the various stages of your LLM application. However, if you have complex security requirements - you may want to use Azure Active Directory. There are several files in the examples folder, each demonstrating different aspects of working with Language Models and the LangChain library. LLM Agent with Tools: Extend the agent with access to multiple tools and test that it uses them to answer questions. embeddings – An initialized embedding API interface, e. add_routes(app. Modular components provide useful abstractions along with a collection of implementations for working with language models. Next, we need to define Neo4j credentials. Use the most basic and common components of LangChain: prompt templates, models, and output parsers. LangChain has a number of components designed to help build Q&A applications, and RAG applications more generally. Reshuffles examples dynamically based on query similarity. See full list on github. 2 days ago · Deprecated since version langchain-core==0. A prompt template consists of a string template. Examples: GPT-x, Bloom, Flan T5, Alpaca, LLama Aug 22, 2023 · Here are a few examples of the diverse types of Chains you can create in Langchain: 1. title('🦜🔗 Quickstart App') The app takes in the OpenAI API key from the user, which it then uses togenerate the responsen. Two RAG use cases which we cover elsewhere are: Q&A over SQL data; Q&A over code (e. A common example would be to convert each example into one human message and one AI message response, or a human message followed Faiss. This notebook goes over how to run llama-cpp-python within LangChain. Overview, Tutorial, and Examples of LangChain. main. For example, imagine you want to use an LLM to answer questions about a specific field, like medicine Introduction to LangChain for Data Engineering & Data Applications. Facebook AI Similarity Search (Faiss) is a library for efficient similarity search and clustering of dense vectors. Your Docusaurus site did not load properly. ) Reason: rely on a language model to reason (about how to answer based on provided Aug 29, 2023 · Executing ‘Hello World’ Program using LangChain. Should contain all inputs specified in Chain. Check out the interactive walkthrough to get started. We call this hierarchical teams because the subagents can in a way be thought of as teams. For more information, please refer to the LangSmith documentation. com Oct 13, 2023 · With easy-to-follow instructions and lucid examples, I’ll guide you through the intricate world of LangChain, unlocking its immense potential. How the text is split: by single character. examples (List[dict]) – List of examples to use in the prompt. Basic components are PromptTemplate, an LLM, and an optional output parser. Let's learn about a popular tool for working with LLMs! LangChain includes a suite of built-in tools and supports several methods for defining your own custom tools . In this guide, we will learn the fundamental concepts of LLMs and explore how LangChain can simplify interacting with large language models. __init__ () aadd_example (example) Add new example to store. Aug 1, 2023 · Models in LangChain are large language models (LLMs) trained on enormous amounts of massive datasets of text and code. LangChain document loaders to load content from files. Install Chroma with: pip install langchain-chroma. So let's figure out how we can use LangChain with Ollama to ask our question to the actual document, the Odyssey by Homer, using Python. Jan 22, 2024 · We will delve into real-world examples and success stories of LLM-powered applications to showcase the wide range of industries where LLMs and LangChain have made a significant impact. Since one of the available tools of the agent is a recommender tool, it decided to utilize the recommender tool by providing the JSON syntax to define its input. ) Reason: rely on a language model to reason (about how to answer based on provided May 31, 2023 · langchain, a framework for working with LLM models. BaseExampleSelector [source] ¶. Now that your environment is ready, you can run your first LangChain command. For instance, . This demo explores how Few-Shot Learning can be done using Langchain. Note 1: This currently only works for plugins with no auth. example_selectors. It accepts a set of parameters from the user that can be used to generate a prompt for a language model. , few-shot examples) or validation for expected parameters. Interface for selecting examples to include in prompts. 0. Recursively split by character. Note: Here we focus on Q&A for unstructured data. It contains algorithms that search in sets of vectors of any size, up to ones that possibly do not fit in RAM. AIMessage, type BaseMessage, We also can use the LangChain Prompt Hub to fetch and / or store prompts that are model specific. 1. See below for examples of each integrated with LangChain. It optimizes setup and configuration details, including GPU usage. Llama. from_template ("User input: {input}SQL query: {query}") prompt = FewShotPromptTemplate (examples = examples [: 5], example_prompt = example_prompt, prefix = "You are a SQLite expert. # This is a long document we can split up. aselect_examples (input_variables) Jan 23, 2024 · Examples: Python; JS; This is similar to the above example, but now the agents in the nodes are actually other langgraph objects themselves. This is the simplest method. However, all that is being done under the hood is constructing a chain with LCEL. How it works. By default, this is set to “AI”, but you can set this to be anything you want. 015, ] Key Features of LCEL is a declarative way to specify a “program” by chainining together different LangChain primitives. We will recreate the AgentExecutor class from LangChain. return_only_outputs ( bool) – Whether to return only outputs in the response. , Python) RAG Architecture A typical RAG application has two main components: 1. This agent will represent all its state as a list of messages. LangChain is a framework for developing applications powered by language models. Simple Diagram of creating a Vector Store Chroma is a AI-native open-source vector database focused on developer productivity and happiness. Note 2: There are almost certainly other ways to do this, this is just a first pass. PromptTemplate [source] ¶. It enables applications that: Are context-aware: connect a language model to sources of context (prompt instructions, few shot examples, content to ground its response in, etc. Use poetry to add 3rd party packages (e. For example, LLMs have to access large volumes of big data, so LangChain organizes these large quantities of In this quickstart we'll show you how to: Get setup with LangChain and LangSmith. For this example, we’ll create a couple of custom tools as well as LangChain’s provided DuckDuckGo search tool to create a research agent. - in-memory - in a python script or jupyter notebook - in-memory with Now, let's go over a more general cyclic example. May 2, 2023 · Knowledge Base: Create a knowledge base of "Stuff You Should Know" podcast episodes, to be accessed through a tool. Now let’s see how to work with the Chat Model (the one that takes in a message instead of a simple string). Its powerful abstractions allow developers to quickly and efficiently build AI-powered applications. The core idea of the library is that we can "chain" together different components to create more advanced use-cases around LLMs. First, we need to install the LangChain package: pip install langchain_community inputs ( Union[Dict[str, Any], Any]) – Dictionary of inputs, or single input if chain expects only one param. To see how this works, let’s create a chain that takes a topic and generates a joke: %pip install --upgrade --quiet langchain-core langchain-community langchain-openai. 5-Turbo, and Embeddings model series. Current configured baseUrl = / (default value) We suggest trying baseUrl = / The basic components of the template are: - examples: A list of dictionary examples to include in the final prompt. They are also used to store information that the framework can access later. """Add new example to store. 010, -0. Because the model can choose to call multiple tools at once (or the same tool multiple times), the example’s outputs are an array: import {. With Non Chat Models LangChain also provides a class for few shot prompt formatting for non chat models: FewShotPromptTemplate. 2. import streamlit as st from langchain. npm i langchain. When contributing an implementation to LangChain, carefully document the model including the initialization parameters, include an example of how to initialize the model and include any relevant Split by character. These templates extract data in a structured format based upon a user-specified schema. Creates a chat template consisting of a single message assumed to be from the human. Using an example set Create the example set A prompt for a language model is a set of instructions or input provided by a user to guide the model's response, helping it understand the context and generate relevant and coherent language-based output, such as answering questions, completing sentences, or engaging in a conversation. PDF. prompt. . LangChain is a framework for including AI from large language models inside data pipelines and applications. Chroma runs in various modes. Sep 29, 2023 · LangChain is a JavaScript library that makes it easy to interact with LLMs. g. prompts import FewShotPromptTemplate, PromptTemplate example_prompt = PromptTemplate. This Python code comes from the end of the Quickstart, and demonstrates an Mar 6, 2024 · Run the code from the terminal: python my-langchain-app. Ollama allows you to run open-source large language models, such as Llama 2, locally. Luckily, LangChain has a built-in output parser of the JSON agent, so we don’t have to worry about implementing it Nov 17, 2023 · This quick start focus mostly on the server-side use case for brevity. There are multiple ways to define a tool. Jul 3, 2023 · inputs ( Union[Dict[str, Any], Any]) – Dictionary of inputs, or single input if chain expects only one param. Create a new code cell and enter/execute the following code: The above Python code is using the LangChain library to interact with an OpenAI model, specifically the “ text-davinci-003 ” model. js and setting up the Open AI API key. Finally, invoke the Vertex AI text generation LLM model to get a well-formatted answer. See the code snippet below for an example. Extraction Using OpenAI Functions: Extract information from text using OpenAI Function Calling. title() method: st. Models I/O LangChain Expression Language (LCEL) LangChain Expression Language, or LCEL, is a declarative way to easily compose chains together. Both will rely on the Embeddings to choose the examples that are most similar to the inputs. " Here are some real-world examples for different types of memory using simple code. LANGSMITH_API_KEY=your-api-key. The API is largely the same, but the output is formatted differently (chat messages vs strings). outputs import GenerationChunk class CustomLLM (LLM): """A custom chat model that echoes the first `n` characters of the input. . llm=llm, verbose=True, memory=ConversationBufferMemory() Basic example: prompt + model + output parser. The most basic and common use case is chaining a prompt template and a model together. OpenAI. It can be used to for chatbots, G enerative Q uestion- A nwering (GQA), summarization, and much more. Users can access the service through REST APIs, Python SDK, or a web ChatGPT Plugins. Custom Let's load the Azure OpenAI Embedding class with environment variables set to indicate to use Azure endpoints. [ Legacy] Chains constructed by subclassing from a legacy Chain class. Code analysis: LangChain can be used to analyse code and find potential bugs or security flaws. Chroma is licensed under Apache 2. langchain app new my-app. This will work with your LangSmith API key. Don’t delay; start leveraging LangChain to build innovative applications today. Let’s discuss some of these modules with examples in Java. In fact, chains created with LCEL implement the entire standard Runnable interface. Note: new versions of llama-cpp-python use GGUF model files (see here ). NotImplemented) 3. We will explore how these applications have transformed customer support, e-commerce, healthcare, and content generation, leading to improved user experiences from langchain_core. See examples of chatbots, summarization, question answering, and more using LangChain and other tools. py: Main loop that allows for interacting with any of the below examples in a continuous manner. """. How the chunk size is measured: by number of characters. A few-shot prompt template can be constructed from either a set of examples, or from an Example Selector object. This splits based on characters (by default “”) and measure chunk length by number of characters. The only method it needs to define is a select_examples method. This is useful for logging, monitoring, streaming, and other tasks. Build a simple application with LangChain. Extraction Using Anthropic Functions: Extract information from text using a LangChain wrapper around the Anthropic endpoints intended to simulate function calling. Oct 10, 2023 · Agent test example 2. Apr 2023 · 11 min read. 4 days ago · Create k-shot example selector using example list and embeddings. 005, 0. Feb 7, 2024 · These 2 Example Selectors from the langchain_core work almost the same way. Models are used in LangChain to generate text, answer questions, translate languages, and much more. 6. A very common reason is a wrong site baseUrl configuration. 3 days ago · class langchain_core. Create new app using langchain cli command. We will use a Vite ReactJs boilerplate for this example. input_keys except for inputs that will be set by the chain’s memory. Feb 20, 2024 · In this example, we asked the agent to recommend a good comedy. LANGCHAIN_TRACING_V2=true. , langchain-openai, langchain-anthropic, langchain-mistral etc). Buffer Memory. You can find your API key in the Azure portal under your Azure OpenAI resource. # Optional, use LangSmith for best-in-class observability. LLMs are large deep-learning models pre-trained on large amounts of data that can generate responses to user queries—for example, answering questions or creating images from text-based prompts. Aug 15, 2023 · Agents use a combination of an LLM (or an LLM Chain) as well as a Toolkit in order to perform a predefined series of steps to accomplish a goal. In this case, LangChain offers a higher-level constructor method. Follow these installation steps to set up a Neo4j database. If you want to get updated when new tutorials are out, get them delivered to your inbox. See the accompanying tutorials on YouTube. This article provides a detailed guide on how to create and use prompt templates in LangChain, with examples and explanations. Update your code to this: from langchain. This example shows how to use ChatGPT Plugins within LangChain abstractions. Let’s walk through an example of that in the example below. Apr 9, 2023 · LangChain provides a standard interface for memory, a collection of memory implementations, and examples of chains/agents that use memory. The template can be formatted using either f-strings (default Mar 25, 2023 · LangChain is a powerful Python library that provides a standard interface through which you can interact with a variety of LLMs and integrate them with your applications and custom data. Takes an input, formats it, and passes it to an LLM for processing. While there are hundreds of examples in the LangChain documentation, I only have room to show you one. For example: If you have a LangChain code that consumes the AzureOpenAI model, you can replace the environment variables with the corresponding key in the Azure OpenAI connection: Import library from promptflow. For a complete list of supported models and model variants, see the Ollama model library. Other Resources The output parser documentation includes various parser examples for specific types (e. Review full docs for full user-facing oauth developer support. Methods. For custom connection, you need to follow the steps: args_schema (Pydantic BaseModel), is optional but recommended, can be used to provide more information (e. classmethodfrom_template(template:str, **kwargs:Any)→ChatPromptTemplate[source] ¶. This is a breaking change. Jan 6, 2024 · For example, let’s say you have a text string “Hello, world!” When you pass this through LangChain’s embedding function, you get an array like [-0. It is build using FastAPI, LangChain and Postgresql. LangChain's memory feature helps to maintain the context of ongoing conversations, ensuring the assistant remembers past instructions, like "Remind me to call John in 30 minutes. Feel free to adapt it to your own use cases. Prompt template for a language model. Jump to Example Using OAuth Access Token to see a short example how to set up Zapier for user-facing situations. Apr 7, 2023 · Mike Young. These templates include instructions, few-shot examples, and specific context and questions appropriate for a given task. LangChain provides tools and abstractions to from langchain_core. js library. OpenAIEmbeddings(). , lists, datetime, enum, etc). Use Case In this tutorial, we'll configure few-shot examples for self-ask with search. interactive_chat. Please see list of integrations. If you're new to Jupyter Notebooks or Colab, check out this video LangChain is a popular framework that allow users to quickly build apps and pipelines around L arge L anguage M odels. connections import AzureOpenAIConnection. chat_models import ChatOpenAI. Jun 1, 2023 · In short, LangChain just composes large amounts of data that can easily be referenced by a LLM with as little computation power as possible. llms import OpenAI Next, display the app's title "🦜🔗 Quickstart App" using the st. It is parameterized by a list of characters. prompts. For tutorials and other end-to-end examples demonstrating ways to integrate Feb 22, 2024 · Installing Langchain. So in the beginning we first process each row sequentially (can be optimized) and create multiple “tasks” that will await the response from the API in parallel and then we process the response to the final desired format sequentially (can also be optimized). stream() returns the response one token at time, and . llama-cpp-python is a Python binding for llama. Each method also has an analogous asynchronous method. This tutorial provides an overview of what you can do with LangChain, including the problems that LangChain solves and examples of data use cases. The base interface is defined as below: """Interface for selecting examples to include in prompts. Developers working on these types of interfaces use various tools to create advanced NLP apps; LangChain streamlines this process. Go to server. LangChain indexing makes use of a record manager ( RecordManager) that keeps track of document writes into the vector store. Importing Necessary Libraries Set environment variables. Aug 20, 2023 · LLMs know to perform better when given some examples about the task they are doing rather than just giving it a prompt. py: Sets up a conversation in the command line with memory using LangChain. Jul 10, 2023 · LangChain also gives us the code to run the chain async, with the arun() function. Note that if you change this, you should also change the prompt used in the chain to reflect this naming change. Use cases Given an llm created from one of the models above, you can use it for many use cases. Apr 7, 2023 12 min. If you have better ideas, please open a PR! There are two types of off-the-shelf chains that LangChain supports: Chains that are built with LCEL. We can connect practically any data source (including our own) to a LangChain agent and ask it questions about In this tutorial, we'll learn how to create a prompt template that uses few-shot examples. Here’s a look at my completed code and response. py. Providers adopt different conventions for formatting tool schemas and tool calls. Given an input question, create a syntactically This notebooks shows how you can load issues and pull requests (PRs) for a given repository on GitHub. We’ll use OpenAI in this example: OPENAI_API_KEY=your-api-key. npm create vite@latest langchain-synonyms -- --template react cd langchain-synonyms npm install. It supports inference for many LLMs models, which can be accessed on Hugging Face. The Hugging Face Model Hub hosts over 120k models, 20k datasets, and 50k demo apps (Spaces), all open source and publicly available, in an online platform where people can easily collaborate and build ML together. These can be called from LangChain either through this local pipeline wrapper or by calling their hosted inference endpoints through Jun 26, 2023 · Then, use the MapReduce Chain from LangChain library to build a high-quality prompt context by combining summaries of all similar toy products. invoke(), but LangChain has other methods that interact with LLMs. These models can be easily adapted to your specific task including but not limited to content generation, summarization, semantic search, and natural language to code translation. It also contains supporting code for evaluation and parameter tuning. Faiss documentation. We will also need an Open AI API key to use the GPT model. 1. To provide reference examples to the model, we will mock out a fake chat history containing successful usages of the given tool. Create a chat prompt template from a template string. It works by taking a big source of data, take for example a 50-page PDF, and breaking it down into "chunks" which are then embedded into a Vector Store. Also shows how you can load github files for a given repository on GitHub. Define the runnable in add_routes. py and edit. """Select which examples to use based on the inputs. Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. LangChain is a framework that simplifies the process of creating generative AI application interfaces. This example goes over how to use the Zapier integration with a SimpleSequentialChain, then an Head to Integrations for documentation on built-in callbacks integrations with 3rd-party tools. We will need to install some LangChain community packages, as well as Tavily to use as an example tool. We will use the LangChain Python repository as an example. ) Reason: rely on a language model to reason (about how to answer based on Dec 1, 2023 · There are two ways you can authenticate to Azure OpenAI: - API Key - Azure Active Directory (AAD) Using the API key is the easiest way to get started. Ollama bundles model weights, configuration, and data into a single package, defined by a Modelfile. LangChain agents aren’t limited to searching the Internet. fb vn ca qj fu zn ph xw vv xo