LangChain

What it is
LangChain is a powerful open-source Python framework that helps developers build applications with Large Language Models (LLMs) by combining prompts, tools, memory, and control logic into modular workflows.

Key features

• Prompt chaining: Chain prompts and models together to build multi-step reasoning flows.
• Tool integration: Plug in APIs, databases, search engines, and more using prebuilt tool wrappers.
• RAG support: Retrieval-augmented generation pipelines with vector store support (FAISS, Qdrant, etc).
• Agent framework: Dynamic decision-making agents that can choose tools and actions at runtime.
• Memory modules: Enable stateful conversations with long-term memory and context handling.
• Observability: Debug, visualize, and trace your LLM chains using LangSmith.