Component Preview

Preview React components in isolation using Ladle (lightweight Storybook alternative) with real Mantine v7 + Tailwind styling. No dev server needed.

When to Use

• After modifying a UI component — proactively offer to preview it
• When the user asks “show me what it looks like” or “generate a preview”
• When debugging visual issues — create a story to reproduce and iterate
• When reviewing component changes before committing

Prerequisites

Ladle is configured in the project root:

• .ladle/components.tsx — Global provider with MantineProvider + theme
• .ladle/config.mjs — Story discovery config
• .ladle/vite.config.ts — Vite config with ~/ path alias + PostCSS

If these don’t exist in the current worktree, copy them from main or create them. See Setup Reference below.

Workflow

1. Create/Update the Story

Create a .stories.tsx file near the component being previewed:

src/components/MyComponent/MyComponent.stories.tsx
src/pages/challenges/EligibleModels.stories.tsx

Story structure:

import { /* Mantine components */ } from '@mantine/core';
// Import the component or recreate the relevant JSX

// Mock data that represents realistic API responses
const mockData = [ ... ];

// Render the component with different states
function Preview({ data }) {
  return (
    <div style={{ width: 320 }}> {/* Constrain to realistic width */}
      <MyComponent data={data} />
    </div>
  );
}

/** Default state */
export const Default = () => <Preview data={mockData} />;

/** Empty state */
export const Empty = () => <Preview data={[]} />;

/** Loading or edge case states */
export const LongList = () => <Preview data={longMockData} />;

Important patterns:

• Set a realistic width on the wrapper (e.g., 320px for sidebar, 600px for main content)
• Copy the exact Mantine component props and Tailwind classes from the real component
• Copy any inline styles props from the parent context (e.g., Accordion styles)
• Use useComputedColorScheme and useMantineTheme if the component uses them
• Create 2-4 variants showing different states (default, empty, single item, overflow)

2. Start Ladle

# Check if Ladle is already running
curl -s -o /dev/null -w "%{http_code}" http://localhost:61111/

# If not running, start it (from project root or worktree root)
cd <worktree-path>
npx ladle serve --port 61111 &
# Wait for it to be ready (~3-5 seconds)

Ladle auto-discovers stories matching src/**/*.stories.tsx.

3. Capture Screenshots

Use the browser-automation skill to capture cropped, padded screenshots:

# Create a browser session
node ~/.claude/skills/browser-automation/cli.mjs session http://localhost:61111 --name ladle

# Capture all story variants in dark and light themes
node ~/.claude/skills/browser-automation/cli.mjs run "
  const stories = [
    { name: 'default', path: 'my-component--default' },
    { name: 'empty', path: 'my-component--empty' },
  ];
  const themes = ['dark', 'light'];
  const dir = '<session-screenshots-dir>';

  for (const theme of themes) {
    for (const story of stories) {
      await page.goto('http://localhost:61111/?story=' + story.path + '&theme=' + theme + '&mode=preview');
      await page.waitForTimeout(800);
      const wrapper = page.locator('.ladle-story-wrapper');
      await wrapper.screenshot({ path: dir + '/crop-' + theme + '-' + story.name + '.png' });
    }
  }
" --label "Component preview screenshots" -s ladle

Story path format: The story path is derived from the file name and export name:

• File: EligibleModels.stories.tsx, Export: Default -> path: eligible-models--default
• File: ModelCard.stories.tsx, Export: WithBadge -> path: model-card--with-badge

Pattern: kebab-case filename + -- + kebab-case export name.

4. Present to User

1. Show screenshots inline using the Read tool on the PNG files
2. Open for the user if they want to see them in their image viewer:

   start "" "<path-to-screenshot>"
   

3. Ask for feedback — “Does this look right? Want me to adjust anything?”
4. Iterate — if they want changes, modify the component, re-capture, re-present

Handling Complex Components

Some components depend heavily on app context. When this happens:

Easy (just do it)

• Presentational components (badges, cards, lists, accordions)
• Components that only use Mantine + Tailwind
• Components with simple props

Medium (mock the data)

• Components that use tRPC data — extract the type and create mock objects
• Components with images — use placeholder divs or null image fallbacks
• Components with links — use <div> or <a href="#"> instead of Next.js <Link>

Hard (raise to user)

• Components deeply coupled to multiple providers (auth, router, tRPC context)
• Components using complex hooks that call APIs
• Components with heavy CSS module dependencies

When encountering hard cases, tell the user:

“This component depends on [auth/router/tRPC context]. I can either:

1. Mock out the dependencies (more setup, more accurate)
2. Extract just the visual parts into the story (faster, close enough)
3. Skip the preview and we can check it on the dev server instead

What would you prefer?”

Setup Reference

If Ladle isn’t configured in the worktree, create these files:

.ladle/components.tsx

import { MantineProvider, createTheme, Modal } from '@mantine/core';
import type { GlobalProvider } from '@ladle/react';

import '@mantine/core/styles.layer.css';
import '../src/styles/globals.css';

// Theme subset from src/providers/ThemeProvider.tsx
const theme = createTheme({
  components: {
    Badge: {
      styles: { leftSection: { lineHeight: 1 } },
      defaultProps: { radius: 'sm', variant: 'light' },
    },
    ActionIcon: {
      defaultProps: { color: 'gray', variant: 'subtle' },
    },
    Tooltip: {
      defaultProps: { withArrow: true },
    },
  },
  colors: {
    dark: ['#C1C2C5','#A6A7AB','#8c8fa3','#5C5F66','#373A40','#2C2E33','#25262B','#1A1B1E','#141517','#101113'],
    blue: ['#E7F5FF','#D0EBFF','#A5D8FF','#74C0FC','#4DABF7','#339AF0','#228BE6','#1C7ED6','#1971C2','#1864AB'],
  },
  white: '#fefefe',
  black: '#222',
});

export const Provider: GlobalProvider = ({ children, globalState }) => (
  <MantineProvider
    theme={theme}
    defaultColorScheme={globalState.theme === 'dark' ? 'dark' : 'light'}
    forceColorScheme={globalState.theme === 'dark' ? 'dark' : 'light'}
  >
    <div className="ladle-story-wrapper" style={{ padding: 24, width: 'fit-content' }}>
      {children}
    </div>
  </MantineProvider>
);

.ladle/config.mjs

/** @type {import('@ladle/react').UserConfig} */
export default {
  stories: 'src/**/*.stories.tsx',
  defaultStory: '',
  viteConfig: '.ladle/vite.config.ts',
};

.ladle/vite.config.ts

import { defineConfig } from 'vite';
import path from 'path';

export default defineConfig({
  resolve: {
    alias: { '~': path.resolve(__dirname, '../src') },
  },
  css: {
    postcss: path.resolve(__dirname, '..'),
  },
});

Ensure Ladle is installed

pnpm add -D @ladle/react

Tips

• Dark theme first — Civitai defaults to dark mode, so capture dark first
• Constrain width — always set a width matching the real context (sidebar = ~320px, main content = ~600px, full page = ~1200px)
• Copy parent styles — if the component lives inside an Accordion, Card, or other container, replicate those parent styles in the story
• Keep stories temporary — stories for one-off reviews can be deleted after; stories for reusable components can stay
• Ladle port — always use 61111 to avoid conflicts with dev server (3000) and other services