Vercel AI SDK
Also known as: AI SDK, ai npm package
The Vercel AI SDK is a TypeScript (a typed version of JavaScript, the language of the web) library that abstracts over the differences between AI providers. Instead of writing separate code for OpenAI, Anthropic, Google, and others, you write once against the SDK's interface and swap models with a single config change. That portability is valuable when model quality and pricing shift quickly, which they do.
The SDK handles the practical plumbing of AI app development: streaming responses to the user in real time (so text appears as it's generated rather than all at once), calling tools and functions during a model's reasoning process, generating structured outputs (JSON-shaped responses rather than free text), and managing multi-turn conversations. These are things you'd otherwise build from scratch for every project.
Because it's tightly integrated with Next.js and Vercel's hosting infrastructure, it's become a natural choice for builders already in that ecosystem. But it's also usable in any Node.js or edge runtime environment. For builders who want to go from AI API call to a production-ready streaming chat interface in a few hours rather than a few days, it's one of the fastest on-ramps available.