Glossary · AI & Agents
LangChain
Overview
What LangChain does
LangChain provides ready-made building blocks for LLM applications so teams do not wire everything from scratch. It offers standard interfaces for prompts, model calls, retrievers, memory, and tools, plus integrations with model providers like OpenAI and vector stores like Pinecone and pgvector. Chains and agents combine these components into multi-step logic. It is available in both Python and JavaScript.
LangChain vs LlamaIndex and related tools
LangChain is broad orchestration; LlamaIndex specializes in data ingestion and retrieval for RAG, and the two are often used together. Within the LangChain ecosystem, LangGraph handles stateful, controllable agents, while LangSmith adds tracing, testing, and monitoring. Choosing among them depends on whether your priority is workflow logic, data retrieval, or agent reliability.
How it fits real projects
LangChain speeds up building chatbots, knowledge assistants, and automations by standardizing the plumbing between models and data. Our team uses it in RAG Development, AI Chatbots, Customer Service AI, and Workflow Automation work, then adds evaluation and guardrails so the finished system is reliable, not just a quick prototype.
Where we use it
Related Zen in Tech services
How our team puts LangChain to work in real projects.
FAQ
LangChain — common questions
What is LangChain used for?
LangChain is used to build LLM-powered applications such as chatbots, RAG systems, and agents. It connects models to data sources, tools, and memory, and orchestrates multi-step workflows, reducing the custom code needed to move from a prototype to a working product.
LangChain vs LlamaIndex, which should I use?
Use LlamaIndex when your focus is indexing and retrieving your own data for RAG, and LangChain when you need broader orchestration of chains, tools, and agents. Many projects use both together, LlamaIndex for retrieval inside a LangChain application.
Is LangChain free?
Yes, LangChain is open-source and free to use. Related commercial products like LangSmith, used for tracing and monitoring, have their own pricing with free and paid tiers.
Need LangChain done right?
Book a free consultation and we’ll map the fastest, most cost-effective path for your project.
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