streamdown

Why we included this project

Anyone building a chat UI around the AI SDK or another provider that streams model output hits the same wall: standard Markdown renderers choke when tokens arrive in half-finished chunks. Streamdown is a React component that renders assistant messages in real time, keeping partially delivered blocks like open code fences readable the moment each token lands. It is a drop-in replacement for react-markdown, so teams with an existing renderer can switch with minimal changes, and it offers GitHub-Flavored Markdown, LaTeX math via KaTeX, Mermaid diagrams, and Shiki code highlighting as optional plugins rather than bundled defaults. The same code powers the AI SDK's official Message component, which makes it the de facto renderer in that ecosystem. The one real setup catch: it depends on shadcn/ui design-token CSS variables, so expect more than a plain npm install unless you already use that stack.