---
name: "@extend"
slug: "extend"
description: "A collection of UI components for building document agents and human-in-the-loop review workflows."
category: "AI/chat UI"
tags: ["ai", "blocks", "buttons", "cards", "dashboard", "editor", "forms", "hooks", "loaders", "media", "mobile", "navigation", "overlays"]
framework: "react"
license: null
author: "extend-hq"
website: "https://ui.extend.ai"
github: "https://github.com/extend-hq/ui"
registry: "https://ui.extend.ai/r/registry.json"
pro: false
pro_url: null
github_stars: 1271
component_count: 55
generated_at: "2026-07-28T08:00:50.948Z"
---

# @extend

A collection of UI components for building document agents and human-in-the-loop review workflows.

## Links

- Website: https://ui.extend.ai
- GitHub: https://github.com/extend-hq/ui
- Registry JSON: https://ui.extend.ai/r/registry.json
- Directory page: https://sh4dcn.vercel.app/registry/extend
- This file: https://sh4dcn.vercel.app/md/extend.md

## Install

```sh
# add the whole registry (shadcn CLI)
npx shadcn@latest add https://ui.extend.ai/r/registry.json
pnpm dlx shadcn@latest add https://ui.extend.ai/r/registry.json
bunx shadcn@latest add https://ui.extend.ai/r/registry.json
# clone the source repo
git clone https://github.com/extend-hq/ui.git
# fetch the raw registry index
curl -s https://ui.extend.ai/r/registry.json
```

## Components (55)

| name | type | description | install |
| --- | --- | --- | --- |
| utils | registry:lib | Shared class name helper used by Extend UI registry components. | `npx shadcn@latest add https://ui.extend.ai/r/utils.json` |
| use-mobile | registry:hook | A media query hook for mobile responsive UI. | `npx shadcn@latest add https://ui.extend.ai/r/use-mobile.json` |
| accordion | registry:ui | A vertically stacked set of expandable content panels. | `npx shadcn@latest add https://ui.extend.ai/r/accordion.json` |
| alert | registry:ui | A callout for displaying contextual messages. | `npx shadcn@latest add https://ui.extend.ai/r/alert.json` |
| aspect-ratio | registry:ui | A small wrapper for preserving media aspect ratios. | `npx shadcn@latest add https://ui.extend.ai/r/aspect-ratio.json` |
| autocomplete | registry:ui | An autocomplete input built on Base UI primitives. | `npx shadcn@latest add https://ui.extend.ai/r/autocomplete.json` |
| badge | registry:ui | A compact label for status, metadata, and categorization. | `npx shadcn@latest add https://ui.extend.ai/r/badge.json` |
| breadcrumb | registry:ui | Navigation breadcrumbs for page hierarchy. | `npx shadcn@latest add https://ui.extend.ai/r/breadcrumb.json` |
| button | registry:ui | A polymorphic button primitive with variants, sizes, and loading state. | `npx shadcn@latest add https://ui.extend.ai/r/button.json` |
| card | registry:ui | A flexible container primitive for grouped content. | `npx shadcn@latest add https://ui.extend.ai/r/card.json` |
| collapsible | registry:ui | A disclosure primitive for expandable content. | `npx shadcn@latest add https://ui.extend.ai/r/collapsible.json` |
| color-picker | registry:ui | A compact popover color picker with hex, RGB, CSS, and HSL input formats. | `npx shadcn@latest add https://ui.extend.ai/r/color-picker.json` |
| command | registry:ui | A command menu surface powered by cmdk. | `npx shadcn@latest add https://ui.extend.ai/r/command.json` |
| dialog | registry:ui | An accessible modal dialog built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/dialog.json` |
| dropdown-menu | registry:ui | A dropdown menu built on Base UI menu primitives. | `npx shadcn@latest add https://ui.extend.ai/r/dropdown-menu.json` |
| input | registry:ui | A styled text input built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/input.json` |
| group | registry:ui | A connected control group primitive for buttons, inputs, separators, and text addons. | `npx shadcn@latest add https://ui.extend.ai/r/group.json` |
| kbd | registry:ui | A keyboard shortcut display primitive. | `npx shadcn@latest add https://ui.extend.ai/r/kbd.json` |
| popover | registry:ui | A floating popover built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/popover.json` |
| scroll-area | registry:ui | A custom scroll area built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/scroll-area.json` |
| select | registry:ui | A select control built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/select.json` |
| separator | registry:ui | A visual separator built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/separator.json` |
| sheet | registry:ui | A side sheet built on Base UI dialog primitives. | `npx shadcn@latest add https://ui.extend.ai/r/sheet.json` |
| sidebar | registry:ui | A responsive application sidebar with menu, rail, and provider primitives. | `npx shadcn@latest add https://ui.extend.ai/r/sidebar.json` |
| skeleton | registry:ui | A loading placeholder with shimmer animation. | `npx shadcn@latest add https://ui.extend.ai/r/skeleton.json` |
| sonner | registry:ui | A themed toast provider for Sonner. | `npx shadcn@latest add https://ui.extend.ai/r/sonner.json` |
| spinner | registry:ui | A compact loading spinner using Hugeicons. | `npx shadcn@latest add https://ui.extend.ai/r/spinner.json` |
| tabs | registry:ui | A tabs primitive built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/tabs.json` |
| tooltip | registry:ui | A tooltip primitive built on Base UI. | `npx shadcn@latest add https://ui.extend.ai/r/tooltip.json` |
| toggle | registry:ui | A two-state command button and grouped toggle controls. | `npx shadcn@latest add https://ui.extend.ai/r/toggle.json` |
| resizable | registry:ui | Resizable panel primitives using react-resizable-panels. | `npx shadcn@latest add https://ui.extend.ai/r/resizable.json` |
| pdf-block-resizable-shell | registry:component | A reusable resizable left document viewer and right review panel shell for PDF-style blocks. | `npx shadcn@latest add https://ui.extend.ai/r/pdf-block-resizable-shell.json` |
| file-upload | registry:ui | A drag-and-drop file upload surface with accepted file type icons and a compact file list. | `npx shadcn@latest add https://ui.extend.ai/r/file-upload.json` |
| file-thumbnail | registry:ui | A compact file preview thumbnail shell for externally generated images, loading states, and fallback states. | `npx shadcn@latest add https://ui.extend.ai/r/file-thumbnail.json` |
| file-system | registry:ui | A macOS Finder-style file browser for flat object-store manifests with icon, list, column, and gallery views. | `npx shadcn@latest add https://ui.extend.ai/r/file-system.json` |
| file-system-block | registry:block | A Finder-style file browser block that opens PDF, DOCX, PowerPoint, XLSX, and image files in large viewer dialogs. | `npx shadcn@latest add https://ui.extend.ai/r/file-system-block.json` |
| pdf-viewer | registry:ui | A PDF viewer with page virtualization, thumbnails, search, zoom, rotation, upload, and page overlay hooks. | `npx shadcn@latest add https://ui.extend.ai/r/pdf-viewer.json` |
| docx-viewer | registry:ui | A DOCX viewer with upload, zoom, theme controls, and read-only rendering. | `npx shadcn@latest add https://ui.extend.ai/r/docx-viewer.json` |
| docx-editor | registry:ui | An experimental DOCX editor with a Word-style toolbar, page thumbnails, import, export, and live document mutation. | `npx shadcn@latest add https://ui.extend.ai/r/docx-editor.json` |
| xlsx-viewer | registry:ui | An XLSX viewer with workbook loading, thumbnails, sheet tabs, upload, zoom, and theme controls. | `npx shadcn@latest add https://ui.extend.ai/r/xlsx-viewer.json` |
| pptx-viewer | registry:ui | A PowerPoint viewer with slide navigation, zoom, upload, download, custom scroll areas, and virtualized thumbnails. | `npx shadcn@latest add https://ui.extend.ai/r/pptx-viewer.json` |
| xlsx-editor | registry:ui | An experimental XLSX editor with formula input, undo and redo, sheet controls, export, and live workbook mutation. | `npx shadcn@latest add https://ui.extend.ai/r/xlsx-editor.json` |
| csv-viewer | registry:ui | A CSV and TSV viewer with parsing, upload, search, zoom, theme-aware grid rendering, and Glide Data Grid. | `npx shadcn@latest add https://ui.extend.ai/r/csv-viewer.json` |
| pdf-dropzone | registry:block | A PDF-only upload dropzone that opens the dropped file in the shared PDF viewer. | `npx shadcn@latest add https://ui.extend.ai/r/pdf-dropzone.json` |
| layout-blocks | registry:ui | A structured layout review panel with typed blocks and confidence cards. | `npx shadcn@latest add https://ui.extend.ai/r/layout-blocks.json` |
| layout-blocks-block | registry:block | A structured layout review block with confidence cards and PDF region overlays. | `npx shadcn@latest add https://ui.extend.ai/r/layout-blocks-block.json` |
| e-signature | registry:block | A PDF signature review block with field overlays and signing actions. | `npx shadcn@latest add https://ui.extend.ai/r/e-signature.json` |
| bounding-box-citations | registry:ui | An extraction citation panel connected to source bounding boxes and editable values. | `npx shadcn@latest add https://ui.extend.ai/r/bounding-box-citations.json` |
| schema-builder | registry:ui | A JSON schema builder with form and JSON views for extraction schemas. | `npx shadcn@latest add https://ui.extend.ai/r/schema-builder.json` |
| bounding-box-citations-block | registry:block | An extraction citation block linked to source PDF bounding boxes. | `npx shadcn@latest add https://ui.extend.ai/r/bounding-box-citations-block.json` |
| document-splits | registry:ui | A split-group review panel for organizing pages into output documents. | `npx shadcn@latest add https://ui.extend.ai/r/document-splits.json` |
| document-splits-block | registry:block | A split-group review block for organizing PDF pages into output documents. | `npx shadcn@latest add https://ui.extend.ai/r/document-splits-block.json` |
| excel-editor | registry:block | A full Excel editor block with workbook upload, cell formatting, merge tools, sheets, zoom, and export controls. | `npx shadcn@latest add https://ui.extend.ai/r/excel-editor.json` |
| docx-editor-block | registry:block | A full DOCX editor block with a Word-style toolbar, page thumbnails, and export controls. | `npx shadcn@latest add https://ui.extend.ai/r/docx-editor-block.json` |
| document-viewer-sidebar | registry:ui | Shared thumbnail sidebar behavior for document viewers, including viewer-width responsive overlay and inline modes. | `npx shadcn@latest add https://ui.extend.ai/r/document-viewer-sidebar.json` |

## For AI agents

```text
You are adding components from @extend to a shadcn-compatible project.
1. Read this file (https://sh4dcn.vercel.app/md/extend.md) for the component list.
2. Fetch the machine-readable index: https://ui.extend.ai/r/registry.json
3. Install a single component with its install command from the table above.
4. Full structured record: https://sh4dcn.vercel.app/json (library slug: extend).
```