AI chat streaming Markdown

The challenge

When an LLM generates Markdown token-by-token, the content is incomplete most of the time. A regular Markdown renderer will flicker, error, or render garbage during the streaming phase. Markstream is designed to handle these intermediate states gracefully.

Key streaming patterns

1. Raw content mode (simplest)

Pass the accumulating Markdown string directly. Markstream handles the parsing and rendering.

tsx

// React
import MarkdownRender from 'markstream-react'
import 'markstream-react/index.css'

function ChatMessage({ content, isDone }: { content: string, isDone: boolean }) {
  return <MarkdownRender content={content} final={isDone} fade={false} />
}

vue

<!-- Vue -->
<template>
  <MarkdownRender mode="chat" :content="content" :final="isDone" :fade="false" />
</template>

2. Pre-parsed nodes mode (high-frequency)

Parse outside the renderer when you want explicit control over parse frequency, batching, and parser instance reuse.

tsx

import MarkdownRender from 'markstream-react'
import { useMemo } from 'react'
import { getMarkdown, parseMarkdownToStructure } from 'stream-markdown-parser'

function ChatMessage({ content, isDone }: { content: string, isDone: boolean }) {
  const md = useMemo(() => getMarkdown('chat-message'), [])
  const nodes = useMemo(
    () => parseMarkdownToStructure(content, md, { final: isDone }),
    [content, isDone, md],
  )

  return <MarkdownRender nodes={nodes} final={isDone} fade={false} />
}

3. Smooth pacing (typewriter effect)

tsx

<MarkdownRender
  content={content}
  final={isDone}
  typewriter
  smoothStreaming="auto"
  smoothStreamingOptions={{
    maxCommitFps: 30,
    minCharsPerSecond: 45,
    maxCharsPerSecond: 1200,
    targetLatencyMs: 900,
  }}
  fade={false}
/>

typewriter shows a blinking cursor while streaming
smooth-streaming="auto" paces content insertion for a natural reading experience
smoothStreamingOptions controls pacing speed — adjust maxCharsPerSecond for faster/slower display
fade={false} prevents opacity animation restarts on each update

SSE integration

tsx

// React SSE example
function ChatView() {
  const [content, setContent] = useState('')
  const [isDone, setIsDone] = useState(false)

  useEffect(() => {
    const eventSource = new EventSource('/api/chat/stream')
    eventSource.onmessage = (event) => {
      if (event.data === '[DONE]') {
        setIsDone(true)
        eventSource.close()
      }
      else {
        setContent(prev => prev + JSON.parse(event.data).content)
      }
    }
    return () => eventSource.close()
  }, [])

  return <MarkdownRender content={content} final={isDone} fade={false} />
}

WebSocket integration

Same pattern as SSE — accumulate the content string or build a nodes array incrementally, then pass to the renderer.

Mode selection

Mode	Best for	Defaults
`chat`	AI chat, SSE, token streams	Steady pacing, no fade, smaller batches
`docs`	Completed documents, VitePress	Fade enabled, tooltips, larger batches
`minimal`	Lightweight surfaces	Same as `chat` defaults, neutral name

Keep the mode stable for a given surface. Switch pacing/animation props (smooth-streaming, typewriter, fade) instead of changing modes mid-stream.

AI chat streaming Markdown ​

The challenge ​

Key streaming patterns ​

1. Raw content mode (simplest) ​

2. Pre-parsed nodes mode (high-frequency) ​

3. Smooth pacing (typewriter effect) ​

SSE integration ​

WebSocket integration ​

Mode selection ​

Framework-specific guides ​