LangChain: AI Agent Framework & Observability Platform
LangChain powers reliable AI agents with open-source framework, LangSmith observability, and production deployment. Used by 35% of Fortune 500.
LangChain is a comprehensive platform for building and deploying AI agents, combining an MIT-licensed open-source framework with LangSmith, a commercial observability and deployment platform. The framework enables rapid development through 1000+ integrations with LLMs, vector databases, and tools. LangSmith provides observability through native tracing, evaluation with human feedback, and managed deployment infrastructure for production AI agents. The platform is designed for long-running, stateful agent workloads requiring persistence, human-in-the-loop approval, and comprehensive monitoring.
Pricing
LangChain framework is free (MIT open-source). LangSmith observability platform: Developer plan free (5K traces/month, 1 seat), Plus $39/seat/month (10K traces, 3 workspaces) with additional traces at $0.50 per 1K and extended trace upgrades at $4.50 per 1K. Enterprise plan custom pricing for self-hosting, BAA, and advanced features.
Frequently Asked Questions
Is LangChain free to use?
Yes, LangChain framework is completely free and open-source under the MIT license. You can use it for personal and commercial projects without any cost. LangSmith (the observability platform) has a free Developer tier with 5,000 traces/month. Paid plans start at $39/month per seat for the Plus tier.
What is the difference between LangChain and LangSmith?
LangChain is an open-source framework for building agents and LLM applications with modular components and 1000+ integrations. LangSmith is a commercial observability, evaluation, and deployment platform built to debug, test, and monitor LangChain applications in production. You can use LangChain without LangSmith, but LangSmith only works with LangChain applications.
Can I use LangChain with any LLM provider?
Yes, LangChain supports 1000+ integrations including OpenAI, Anthropic Claude, Google Gemini, Hugging Face, Cohere, Mistral, and many others. You can swap between model providers without rewriting your application code.
Is LangSmith HIPAA and SOC 2 compliant?
Yes, LangSmith is SOC 2 Type II certified, HIPAA compliant, and GDPR compliant. However, Business Associate Agreements (BAAs) are only available on the Enterprise plan. Self-hosting options with BYOC (bring-your-own-cloud) or fully managed are exclusively available for Enterprise customers.
Can I self-host LangSmith?
Self-hosting LangSmith is only available on the Enterprise tier. You have three deployment options: managed cloud (default), bring-your-own-cloud (BYOC), or fully self-hosted on your own Kubernetes infrastructure. Self-hosting requires significant infrastructure investment (minimum 16+ vCPU, 64+ GB RAM).
What is LangGraph and how does it differ from LangChain?
LangGraph is a framework for building stateful, long-running agent workflows with built-in persistence, checkpointing, and human-in-the-loop support. LangChain provides rapid agent building with templates and integrations. LangGraph offers lower-level control for complex multi-step agent orchestration and is complementary to LangChain.
How much do traces cost in LangSmith Plus?
LangSmith Plus includes 10,000 base traces free per month at $39/seat. Beyond that, additional base traces cost $0.50 per 1,000 traces. Extended traces (with feedback) cost $4.50 per 1,000 traces to upgrade. Plus tier also includes 1 free dev-sized deployment.