LangChain Python Tutorial: 2026’s Complete Guide | The PyCharm Blog

LangChain is a versatile framework designed for building AI agents powered by large language models (LLMs) from providers such as OpenAI, Anthropic, and Google, offering a straightforward way for both beginners and advanced users to develop AI systems. It supports static and dynamic agent models, allowing agents to switch models during runtime based on context, and incorporates tools that enable agents to interact with external systems beyond just generating text. LangChain also features middleware for customizing agent behavior and implementing guardrails for safe AI operations, along with testing capabilities to ensure reliable performance. Real-world applications of LangChain include AI-powered chatbots, document question answering systems, and content generation tools, demonstrating its adaptability across various domains. LangChain integrates with development environments like PyCharm, enhancing the development experience with debugging tools. Built on LangGraph, LangChain sets a new standard for developing AI agents, combining low-level orchestration with broad compatibility across different LLMs.