Brilliant - AI-Powered Calendar

An intelligent calendar application with conversational AI capabilities, built with React and integrated with Google Calendar. Schedule, manage, and reorganize your events naturally through chat.

Thanks to: big-calendar.vercel.app - A fantastic open-source calendar project that influenced the visual design and user experience patterns.

✨ Features

Calendar Views

Day View: Focus on a single day with time-based event layout
Week View: See your entire week at a glance with multi-day event support
Month View: Monthly overview with event indicators
Drag-and-drop event creation
Current time indicator with auto-scroll

AI-Powered Scheduling (via Tambo)

Chat naturally to manage your calendar:

"Schedule a team meeting tomorrow at 2pm for 1 hour"
"Block out focus time every weekday morning"
"Move my dentist appointment to next Thursday and add a gym session on Monday"
"What do I have scheduled this week?"

Google Calendar Sync

Two-way synchronization with Google Calendar
Recurring event support (daily, weekly, monthly, yearly)
Color mapping from Google Calendar
Automatic sync every 60 seconds
Batch-parallel sync queue (5 concurrent API calls)

🛠 Tambo Features Used

This project demonstrates several Tambo capabilities:

AI Tools (Function Calling)

| Tool | Description | | --------------------- | --------------------------------------------------------------- | | createCalendarEvent | Create a single event with optional recurrence | | getCalendarEvents | Query events within a date range | | updateCalendarEvent | Modify a single existing event | | deleteCalendarEvent | Remove a single event | | batchCalendarUpdate | Preferred for 2+ changes — create/update/delete in one call |

The batchCalendarUpdate tool uses a JSON string for operations to avoid Tambo's streaming object decomposition. See ARCHITECTURE.md for details.

Context Helpers

The AI receives real-time awareness of the user's calendar without registering extra tools:

| Helper | Data | | ----------------------- | ------------------------------------------------ | | userTimeContext | Current time + timezone | | calendarViewContext | Selected date, view type, range description | | upcomingEventsContext | Visible events with IDs (filtered to exact view) |

Generative Components

GenerativeForm: Dynamic, schema-driven forms for structured data collection

Thread Management

Auto-generated thread names
Thread history with conversation switching
Checkpoint-based undo/revert system

🏗 Architecture

See ARCHITECTURE.md for the full architecture documentation including:

System diagrams and data flow
Directory structure
State management (Jotai atoms)
AI tool + context helper design
Google Calendar sync pipeline
Design decisions and trade-offs

High-Level Flow

graph LR
    A[User] --> B[Chat Interface]
    A --> C[Calendar UI]
    B --> D[Tambo AI]
    D --> E[AI Tools]
    E --> F[Jotai State]
    C --> F
    F --> G[Google Calendar Sync]
    G -->|batch parallel| H[Google Calendar API]
    H --> G
    G --> F

⚠️ Known Limitations

Token Refresh (No Backend)

This app uses Google's OAuth2 Implicit Grant Flow, which only provides short-lived access tokens (~1 hour). There are no refresh tokens without a backend server implementing the Authorization Code flow.

Current behavior: When the token expires, users see a re-authentication dialog.

Recurrence Support

Supported:

✅ Daily, Weekly, Monthly, Yearly frequency
✅ Interval (every N days/weeks/etc.)
✅ Count-based and end-date limits
✅ BYDAY for weekly recurrence

Not yet supported:

❌ BYSETPOS, BYMONTHDAY complex rules
❌ Exception dates (EXDATE)

Performance

For users with very large event counts (1000+), client-side recurring event expansion may impact performance.

🚀 Getting Started

Prerequisites

Node.js 18+
pnpm
Google Cloud Console project with Calendar API enabled

Environment Variables

VITE_TAMBO_API_KEY=your_tambo_api_key
VITE_GOOGLE_CLIENT_ID=your_google_client_id

Installation

pnpm install
pnpm dev

📝 License

MIT

Brilliant

Install / Use

README