Installation

Langchain as a framework consists of a number of packages. They're split into different packages allowing you to choose exactly what pieces of the framework to install and use.

Installing essential Langchain.dart packages

`langchain`

Contains higher-level and use-case specific chains, agents, and retrieval algorithms that are at the core of the application's cognitive architecture.

Depend on this package to build LLM applications with Langchain.dart.

This package exposes langchain_core so you don't need to depend on it explicitly.

dart pub add langchain

`langchain_core`

This package contains base abstractions of different components and ways to compose them together. The interfaces for core components like LLMs, vector stores, retrievers and more are defined here.

Depend on this package to build frameworks on top of Langchain.dart or to interoperate with it.

To install this package in your Dart or Flutter project

dart pub add langchain_core

`langchain_community`

Contains third-party integrations and community-contributed components that are not part of the core Langchain.dart API.

Depend on this package if you want to use any of the integrations or components it provides like CSV,JSON,Text or HTML loaders and more.

dart pub add langchain langchain_community

Integration packages

Certain integrations like OpenAI and Anthropic have their own packages. Any integrations that require their own package will be documented as such in the Integration docs.

Let's say you're using OpenAI, install the langchain_openai package.

dart pub add langchain langchain_community langchain_openai

Let's say you want Google integration to use (GoogleAI, VertexAI, Gemini etc), install the langchain_google package.

dart pub add langchain langchain_community langchain_google

The following table contains the list of existing Langchain.dart integration packages.

Package	Version	Description
langchain_core		Core abstractions and LCEL
langchain		Higher-level and use-case specific chains, agents, and retrieval algorithms
langchain_community		Third-party integrations (without specific packages) and community-contributed components and utilities
langchain_openai		OpenAI integration (GPT-3.5 Turbo, GPT-4, GPT-4o, Embeddings, Tools, Vision, DALL·E 3, etc.) and OpenAI Compatible services (TogetherAI, Anyscale, OpenRouter, One API, Groq, Llamafile, GPT4All, etc.)
langchain_google		Google integration (GoogleAI, VertexAI, Gemini, PaLM 2, Embeddings, Vector Search, etc.)
langchain_firebase		Firebase integration (VertexAI for Firebase (Gemini 1.5 Pro, Gemini 1.5 Flash, etc.))
langchain_ollama		Ollama integration (Llama 3, Phi-3, WizardLM-2, Mistral 7B, Gemma, CodeGemma, Command R, LLaVA, DBRX, Qwen 1.5, Dolphin, DeepSeek Coder, Vicuna, Orca, etc.)
langchain_mistralai		Mistral AI integration (Mistral-7B, Mixtral 8x7B, Mixtral 8x22B, Mistral Small, Mistral Large, embeddings, etc.).
langchain_pinecone		Pinecone vector database integration
langchain_chroma		Chroma vector database integration
langchain_supabase		Supabase Vector database integration