Vercel AI SDK vs LangChain / LangGraph
Side-by-side comparison of Vercel AI SDK and LangChain / LangGraph. Pricing, features, best use cases, and honest verdict from a developer who has tested both.
Vercel AI SDK
EssentialThe TypeScript toolkit for building AI apps. Unified API across OpenAI, Anthropic, Google. Streaming, tool calling, structured output, multi-step agents. 50K+ GitHub stars.
LangChain / LangGraph
Most popular LLM framework. 100K+ GitHub stars. Chains, RAG, vector stores, tool use. LangGraph adds stateful multi-agent workflows with cycles and persistence.
Feature Comparison
| Feature | Vercel AI SDK | LangChain / LangGraph |
|---|---|---|
| Category | AI Frameworks | AI Frameworks |
| Type | SDK / Framework | SDK / Framework |
| Pricing | See website for pricing | See website for pricing |
| Best For | TypeScript AI apps with streaming and tool use | RAG, chains, and stateful agent workflows |
| Language / Platform | TypeScript | Python |
| Open Source | No | No |
In Depth
Vercel AI SDK
The Vercel AI SDK is the standard TypeScript library for building AI-powered applications. It provides a unified interface - write code once, swap between OpenAI, Anthropic, Google, or any provider. Key features: streaming chat responses, structured JSON output with Zod schemas, tool calling with automatic execution, and multi-step agent loops. The `ai` core package handles the LLM interaction, `ai/react` provides React hooks (useChat, useCompletion), and `ai/rsc` enables server-side streaming with React Server Components. Over 50K GitHub stars. I use it in nearly every project and built a complete course on it for this site.
LangChain / LangGraph
LangChain is the most popular framework for building LLM applications, with over 100K GitHub stars. It provides abstractions for chains (sequential LLM calls), RAG (retrieval-augmented generation with any vector store), tool use, and output parsing. LangGraph extends it with stateful, graph-based workflows - agents that can loop, branch, and persist state across interactions. Their latest push is 'Deep Agents' for autonomous coding. LangSmith provides observability and tracing. The ecosystem is massive - integrations with every model provider, vector database, and tool imaginable. I cover LangChain in my AI Agent Frameworks course.
The Verdict
Both Vercel AI SDK and LangChain / LangGraph are strong tools in the ai frameworks space. The right choice depends on your workflow. Read the full review of each tool for a deeper dive, or watch the video walkthroughs to see them in action.