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Chat UI Recipes

Ask the user your own question

Use defineInterrupt when the question is not about approving a tool. The server pauses the run and asks. Your component answers.

Two schemas define the exchange:

  1. payloadSchema is what the server sends you.
  2. responseSchema is what you send back.

Define it

tsx
import { defineInterrupt } from '@tanstack/ai'
import { z } from 'zod'

export const choosePlan = defineInterrupt({
  id: 'choosePlan',
  payloadSchema: z.object({
    options: z.array(z.string()),
  }),
  responseSchema: z.string(),
})

The server sends a list of plan names. You send one name back.

Render it

Add the interrupt to chatOptions, then register a component under interruptsComponents.generic. The key is the interrupt id.

tsx
import { fetchServerSentEvents } from '@tanstack/ai-react'
import { createChatHook } from '@tanstack/ai-react/ui'

const chatOptions = {
  connection: fetchServerSentEvents('/api/chat'),
  interrupts: [choosePlan],
}

const { useAppChat } = createChatHook({
  options: chatOptions,
  components: {
    layout: ({ Messages, Interrupts }) => (
      <main>
        <Messages />
        <Interrupts />
      </main>
    ),
    message: ({ Parts }) => <article><Parts /></article>,
  },
  partsComponents: {
    text: ({ part }) => <p>{part.content}</p>,
    fallback: () => null,
  },
  interruptsComponents: {
    generic: {
      choosePlan: ({ interrupt }) => (
        <fieldset>
          <legend>Pick a plan</legend>
          {interrupt.payload?.options.map((plan) => (
            <button key={plan} onClick={() => interrupt.resolveInterrupt(plan)}>
              {plan}
            </button>
          ))}
        </fieldset>
      ),
      fallback: ({ interrupt }) => <p>{interrupt.reason}</p>,
    },
  },
})

export function PlanChat() {
  const chat = useAppChat()
  return <chat.AppChat />
}

interrupt.payload matches your payloadSchema, so options is a string array. resolveInterrupt accepts only what your responseSchema allows, so passing a number here is a compile error.

Generic interrupts always render in the list

A tool approval can render next to its tool. A generic interrupt cannot, because no tool owns it. Render Interrupts in your layout or it never appears.

Always register a fallback

fallback catches two things:

  1. An interrupt id you did not register.
  2. An unbound interrupt, which arrives with no id at all.

Branch on interrupt.kind === 'unbound' when the copy must differ.

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