CopilotChatAssistantMessage

Overview

CopilotChatAssistantMessage displays assistant messages with Markdown support, tool call rendering, and an action toolbar. The Markdown renderer uses remark-gfm, remark-math, syntax highlighting via rehype-pretty-code, and KaTeX support for mathematical expressions. The toolbar provides copy, rating (thumbs up/down), read aloud, and regenerate buttons with localized tooltips sourced from CopilotChatConfigurationProvider.

Import

import { CopilotChatAssistantMessage } from "@copilotkit/react-core/v2";
import "@copilotkit/react-core/v2/styles.css";

Props

<PropertyReference name="onThumbsDown" type="(message: AssistantMessage) => void"

Callback invoked when the user clicks the thumbs-down button. When not provided, the thumbs-down button is hidden from the toolbar. </PropertyReference>

<PropertyReference name="onReadAloud" type="(message: AssistantMessage) => void"

Callback invoked when the user clicks the read-aloud button. When not provided, the read-aloud button is hidden from the toolbar. </PropertyReference>

<PropertyReference name="onRegenerate" type="(message: AssistantMessage) => void"

Callback invoked when the user clicks the regenerate button. When not provided, the regenerate button is hidden from the toolbar. </PropertyReference>

Slots

All slot props follow the CopilotKit slot system: each accepts a replacement React component, a className string that is merged into the default component's classes, or a partial props object that extends the default component.

As a replacement component:

<CopilotChatAssistantMessage
  message={msg}
  markdownRenderer={({ content }) => (
    <div dangerouslySetInnerHTML={{ __html: content }} />
  )}
/>

As a className:

<CopilotChatAssistantMessage message={msg} toolbar="border-t pt-2 mt-2" />

<PropertyReference name="copyButton" type="SlotProp<typeof CopilotChatAssistantMessage.CopyButton>"

Slot for the copy-to-clipboard button in the toolbar. Defaults to CopilotChatAssistantMessage.CopyButton. The tooltip label is sourced from CopilotChatLabels.assistantMessageToolbarCopyMessageLabel. </PropertyReference>

<PropertyReference name="thumbsUpButton" type="SlotProp<typeof CopilotChatAssistantMessage.ThumbsUpButton>"

Slot for the thumbs-up rating button. Defaults to CopilotChatAssistantMessage.ThumbsUpButton. Only rendered when onThumbsUp is provided. The tooltip label is sourced from CopilotChatLabels.assistantMessageToolbarThumbsUpLabel. </PropertyReference>

<PropertyReference name="thumbsDownButton" type="SlotProp<typeof CopilotChatAssistantMessage.ThumbsDownButton>"

Slot for the thumbs-down rating button. Defaults to CopilotChatAssistantMessage.ThumbsDownButton. Only rendered when onThumbsDown is provided. The tooltip label is sourced from CopilotChatLabels.assistantMessageToolbarThumbsDownLabel. </PropertyReference>

<PropertyReference name="readAloudButton" type="SlotProp<typeof CopilotChatAssistantMessage.ReadAloudButton>"

Slot for the read-aloud button. Defaults to CopilotChatAssistantMessage.ReadAloudButton. Only rendered when onReadAloud is provided. The tooltip label is sourced from CopilotChatLabels.assistantMessageToolbarReadAloudLabel. </PropertyReference>

<PropertyReference name="regenerateButton" type="SlotProp<typeof CopilotChatAssistantMessage.RegenerateButton>"

Slot for the regenerate button. Defaults to CopilotChatAssistantMessage.RegenerateButton. Only rendered when onRegenerate is provided. The tooltip label is sourced from CopilotChatLabels.assistantMessageToolbarRegenerateLabel. </PropertyReference>

<PropertyReference name="toolCallsView" type="SlotProp<typeof CopilotChatToolCallsView>"

Slot for rendering tool calls embedded in the assistant message. Defaults to CopilotChatToolCallsView, which iterates over the message's tool calls and renders each using the closest registered tool renderer. </PropertyReference>

CopilotChatToolCallsView

A companion component that renders the tool calls contained in an assistant message. Given an assistant message, it iterates over each tool call and renders it using the closest registered tool renderer (registered via useFrontendTool, useHumanInTheLoop, or renderToolCalls on the provider).

Import

Props

Usage

Basic Assistant Message

function AssistantBubble({ message }) {
  return (
    <CopilotChatAssistantMessage
      message={message}
      onThumbsUp={(msg) => console.log("Thumbs up:", msg.id)}
      onThumbsDown={(msg) => console.log("Thumbs down:", msg.id)}
    />
  );
}

Customizing the Toolbar

function CustomToolbarMessage({ message }) {
  return (
    <CopilotChatAssistantMessage
      message={message}
      onRegenerate={(msg) => handleRegenerate(msg)}
      onReadAloud={(msg) => speak(msg.content)}
      additionalToolbarItems={
        <button onClick={() => shareMessage(message)}>Share</button>
      }
      toolbar="border-t border-gray-200 pt-2"
    />
  );
}

Hiding the Toolbar

function MinimalMessage({ message }) {
  return (
    <CopilotChatAssistantMessage message={message} toolbarVisible={false} />
  );
}

Custom Markdown Renderer

function CustomRendererMessage({ message }) {
  return (
    <CopilotChatAssistantMessage
      message={message}
      markdownRenderer={({ content }) => (
        <ReactMarkdown>{content}</ReactMarkdown>
      )}
    />
  );
}

Standalone Tool Calls View

function ToolCallsList({ message, allMessages }) {
  return (
    <div className="tool-calls">
      <CopilotChatToolCallsView message={message} messages={allMessages} />
    </div>
  );
}

Behavior

• Markdown Support: The default Markdown renderer supports GitHub Flavored Markdown (tables, strikethrough, task lists), math expressions rendered with KaTeX, and syntax-highlighted code blocks via rehype-pretty-code.
• Toolbar Visibility: The toolbar appears on hover or focus by default. Individual buttons are only rendered when their corresponding callback prop (onThumbsUp, onThumbsDown, onReadAloud, onRegenerate) is provided. The copy button is always visible when the toolbar is shown.
• Localized Labels: All toolbar button tooltips are sourced from the nearest CopilotChatConfigurationProvider. See useCopilotChatConfiguration for the full list of label keys.
• Tool Call Rendering: Tool calls embedded in the assistant message are rendered by the toolCallsView slot. Each tool call is resolved using the useRenderToolCall hook, which looks up registered renderers by tool name.
• Slot System: Each slot prop accepts three forms -- a replacement component, a className string merged into the default, or a partial props object that extends the default component's props.

Related

• CopilotChatMessageView -- Parent component that uses this as the default assistant message slot
• CopilotChatUserMessage -- Companion component for user messages
• useRenderToolCall -- Hook used internally for resolving tool call renderers
• useCopilotChatConfiguration -- Provider for localized toolbar labels