nextjs-shadcn

Requires installing components via bunx --bun shadcn@latest add (never hand-written) to @/modules/cores/shadcn/components/ui/, and covers MCP registry tools (mcp__shadcn__*) for discovering components before implementing. This is the Next.js App Router variant of shadcn/ui — for a plain React/Vite app see react-shadcn instead.

shadcn/ui for Next.js

Beautiful, accessible components built on Radix UI with Tailwind CSS styling.

Agent Workflow (MANDATORY)

Before ANY implementation, spawn 3 agents in parallel, one Agent call each with a name:

1. fuse-ai-pilot:explore-codebase - Analyze existing components and patterns
2. fuse-ai-pilot:research-expert - Verify latest shadcn/ui docs via Context7/Exa
3. mcp__shadcn__* - Search registry for component availability

After implementation, run fuse-ai-pilot:sniper for validation.

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Overview

When to Use

• Building UI components for Next.js App Router applications
• Need accessible, customizable form components (inputs, selects, checkboxes)
• Implementing dialogs, sheets, drawers, or overlay patterns
• Creating data tables with sorting, filtering, and pagination
• Building navigation menus, sidebars, or command palettes
• Need toast notifications or alert feedback components

Why shadcn/ui

Feature	Benefit
Copy/paste model	Components copied to your project, full ownership
Radix UI foundation	Accessibility built-in, unstyled primitives
Tailwind CSS styling	Utility-first, easy customization
TanStack Form ready	Modern form library with Field pattern
Server Components	RSC-compatible, optimal bundle size
Lucide icons	Consistent, customizable icon set

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Critical Rules

1. NEVER create components manually - Always install with bunx --bun shadcn@latest add
2. TanStack Form only - NOT React Hook Form for all form implementations
3. Radix UI primitives - Components built on Radix (NOT Base UI)
4. Lucide icons - Default icon library, NOT Remix icons or others
5. Field pattern - Use Field, FieldLabel, FieldError for form fields
6. SOLID paths - Components at @/modules/cores/shadcn/components/ui/

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Architecture

Component Foundation

• Radix UI - Headless, accessible primitives (Dialog, Select, Popover, Tabs)
• Tailwind CSS v4 - Styling via utility classes, CSS-first config
• class-variance-authority - Variant management for component styles
• clsx + tailwind-merge - Conditional class composition via cn() utility

Project Structure

Components installed to @/modules/cores/shadcn/components/ui/ following SOLID architecture. Utils at @/modules/cores/lib/utils.ts with cn() helper function.

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MCP Server Integration

Create .mcp.json at project root for Claude Code integration with shadcn registry.

Available MCP Tools

• mcp__shadcn__search_items_in_registries - Search available components
• mcp__shadcn__view_items_in_registries - View component source code
• mcp__shadcn__get_item_examples_from_registries - Get usage examples
• mcp__shadcn__get_add_command_for_items - Get installation commands

See installation.md for complete MCP setup.

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Component Categories

Category	Components	Primary Reference
Setup	Init, configuration, theming, icons	installation.md
Forms	Button, Input, Field, Select, Checkbox, Switch, Slider	field-patterns.md
Overlay	Dialog, Sheet, Drawer, Popover, Tooltip, HoverCard	dialog.md
Feedback	Alert, Toast (Sonner), Progress, Skeleton, Spinner	toast.md
Data Display	Table, Badge, Avatar, Calendar, Chart, Carousel	table.md
Navigation	Breadcrumb, DropdownMenu, Command, Sidebar, Tabs	sidebar.md
Layout	Card, Accordion, Separator, ScrollArea, Resizable	card.md

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Best Practices

1. Field components - Use new Field pattern for consistent form field structure
2. Server Components default - Add 'use client' only when interactivity needed
3. Sonner for toasts - Modern toast notifications over legacy toast
4. MCP tools first - Use mcp__shadcn__* to explore before implementing
5. Theming via CSS variables - Customize colors in globals.css :root
6. Accessibility - Rely on Radix UI keyboard navigation and ARIA

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Reference Guide

Need	Reference
Initial setup	installation.md, configuration.md
Form patterns	field-patterns.md, form-examples.md
Theme customization	theming.md
Data tables	table.md
Modal dialogs	dialog.md, alert-dialog.md
Navigation	sidebar.md, navigation-menu.md