VLLNT UI vs Vercel AI SDK
These aren't competitors — they're layers. The Vercel AI SDK is the data layer that streams tokens and talks to model providers. VLLNT UI is the design system that renders the result: chat input, message bubbles, streaming text, tool calls, citations, and artifacts. Most AI apps want both.
| Attribute | VLLNT UI | Vercel AI SDK |
|---|---|---|
| What it is | A UI design system — presentational React components you own | A runtime/data layer — streaming, useChat, model providers |
| Primary job | How the AI app looks and behaves (chat, tools, citations, artifacts) | How the AI app talks to models and streams responses |
| Component breadth | Full design system — chat plus the rest of the product UI | Focused on chat/conversation primitives |
| You own the source | Yes — installed via shadcn CLI into your repo | Consumed as an npm dependency |
| Agent-readable registry | Yes — llms.txt, llms-full.txt, per-component JSON | No |
| Best together? | Use VLLNT UI for the interface | Use the AI SDK for the data layer — they compose cleanly |