langchain-architecture

# LangChain & LangGraph Architecture Master modern LangChain 1.x and LangGraph for building sophisticated LLM applications with agents, state management, memory, and tool integration. ## When to Use This Skill - Building autonomous AI agents with tool access - Implementing complex multi-step LLM workflows - Managing conversation memory and state - Integrating LLMs with external data sources and APIs - Creating modular, reusable LLM application components - Implementing document processing pipelines - Building production-grade LLM applications ## Package Structure (LangChain 1.x) ``` langchain (1.2.x) # High-level orchestration langchain-core (1.2.x) # Core abstractions (messages, prompts, tools) langchain-community # Third-party integrations langgraph # Agent orchestration and state management langchain-openai # OpenAI integrations langchain-anthropic # Anthropic/Claude integrations langchain-voyageai # Voyage AI embeddings langchain-pinecone # Pinecone vector store ``` ## Core Concepts ### 1. LangGraph Agents LangGraph is the standard for building agents in 2026. It provides: **Key Features:** - **StateGraph**: Explicit state management with typed state - **Durable Execution**: Agents persist through failures - **Human-in-the-Loop**: Inspect and modify state at any point - **Memory**: Short-term and long-term memory across sessions - **Checkpointing**: Save and resume agent state **Agent Patterns:** - ...