docs: Add instructions for shadcn/ui.

AGENTS.md

@@ -81,6 +81,7 @@ The command outputs instructions for setting the required environment variable t
 - **Naming**: PascalCase for components, camelCase for variables/functions
 - **Types**: Use `import type` for type-only imports, define interfaces/types
 - **Styling**: Tailwind CSS with `clsx` utility for conditional classes
+- **UI Components**: shadcn/ui components for consistent design system
 - **Icons**: lucide-react with consistent naming
 - **Data fetching**: @tanstack/react-query with proper error handling
 - **Components**: Functional components with hooks, proper TypeScript typing
@@ -94,7 +95,7 @@ The command outputs instructions for setting the required environment variable t
 - **Routes**: `frontend/src/routes/` - TanStack Router file-based routing
 
 ### Key Components Location
-- **UI Components**: `frontend/src/components/ui/` - Reusable UI primitives
+- **UI Components**: `frontend/src/components/ui/` - shadcn/ui components and reusable UI primitives
 - **Feature Components**: `frontend/src/components/` - Main app components
 - **Pages**: `frontend/src/routes/` - Route components (index.tsx, transactions.tsx, etc.)
 - **Hooks**: `frontend/src/hooks/` - Custom React hooks
@@ -121,6 +122,16 @@ The command outputs instructions for setting the required environment variable t
   - Avoid including specific numbers, counts, or data-dependent information that may become outdated
 - **Security**: Never log sensitive data, use environment variables for secrets
 
+## AI Development Support
+
+### shadcn/ui Integration
+This project uses shadcn/ui for consistent UI components. The MCP server is configured for AI agents to:
+- Search and browse available shadcn/ui components
+- View component implementation details and examples
+- Generate proper installation commands for new components
+
+Use the shadcn MCP tools when working with UI components to ensure consistency with the existing design system.
+
 ## Contributing Guidelines
 
 This repository follows conventional changelog practices. Refer to `CONTRIBUTING.md` for detailed contribution guidelines including:

CONTRIBUTING.md

@@ -1,9 +1,19 @@
 # Contributing
 
-Install Poetry and run `poetry install` to install dependencies. Then run `poetry shell` to activate the virtual environment.
+This project uses **uv** for Python dependency management and **shadcn/ui** for frontend components.
+
+## Setup
+Install uv and run `uv sync` to install dependencies.
 
 Run `pre-commit install` to install the pre-commit hooks.
 
+## Frontend Development
+The frontend uses shadcn/ui components for consistent design. When adding new UI components:
+- Check if a shadcn/ui component exists for your use case
+- Follow the existing component patterns in `frontend/src/components/ui/`
+- Use Tailwind CSS classes for styling
+- Ensure components are accessible and follow the design system
+
 ## Commit messages
 
 type(scope/[subscope]): Title starting with uppercase and sentence ending with period.

README.md

@@ -20,6 +20,7 @@ Having your bank data accessible through both CLI and REST API gives you the pow
   - [React](https://reactjs.org/): Modern web interface with TypeScript
   - [Vite](https://vitejs.dev/): Fast build tool and development server
   - [Tailwind CSS](https://tailwindcss.com/): Utility-first CSS framework
+  - [shadcn/ui](https://ui.shadcn.com/): Modern component system built on Radix UI
   - [TanStack Query](https://tanstack.com/query): Powerful data synchronization for React
 
 ## ✨ Features