LangChain

LangChain is one of the default frameworks teams reach for when they need to connect models, tools, retrieval systems, memory, and agent control flow without starting from raw API calls. The current positioning is explicitly agent-oriented: LangChain provides prebuilt agent patterns, middleware, model and tool integrations, and a path into LangGraph's durable runtime for persistence, checkpointing, rewind, and human-in-the-loop workflows.

The strongest reason to add LangChain to a stack is ecosystem leverage. It has a large integration surface and a lot of community knowledge, which helps teams move quickly when model providers, vector stores, and application patterns keep changing. The tradeoff is abstraction discipline. LangChain is powerful, but production teams should keep a close eye on where framework convenience ends and explicit application architecture should begin.