---
title: Follow-up Suggestions
description: AI-generated contextual follow-up questions after responses
---

## Overview

After the AI responds, ChatJS can generate contextual follow-up questions using a fast, cheap model. These appear as clickable buttons below the last assistant message. Clicking a suggestion sends it as a new user message.

## Quick Start

Enable follow-up suggestions in `chat.config.ts`:

```ts
ai: {
  tools: {
    followupSuggestions: {
      enabled: true,
    },
  },
}
```

No API keys or external services are required. Suggestions use one of your existing language model providers.

## How It Works

1. The main AI response completes
2. A fast model generates 3-5 contextual follow-up questions
3. Suggestions stream to the client as the model produces them
4. They render as buttons below the last assistant message
5. Clicking a suggestion sends it as a new user message

Suggestions are UI-only. They are never included in the conversation context sent to the LLM.

## Configuration

### Model Selection

Configure which model generates suggestions in `chat.config.ts`:

```ts
ai: {
  tools: {
    followupSuggestions: {
      enabled: true,
      default: "google/gemini-2.5-flash-lite",
    },
  },
}
```

Use a fast, inexpensive model here. The suggestions prompt is lightweight and does not require a powerful model.

## Related

- [Follow-up Questions Cookbook](/cookbook/follow-up-questions) for implementation details and code walkthrough