# Online Clipboard - Complete Documentation & Agent Specification

Online Clipboard is a zero-setup browser tool that allows users and autonomous agents to share snippets of text, links, code, and local files across disparate hardware platforms and operating systems in real time.

## 1. System Architecture
- **Front-End**: Next.js App Router, Tailwind CSS, lightweight Lucide icons.
- **Signaling Layer**: Firebase Realtime Database for ephemeral session coordination and WebRTC signaling.
- **Data Transfer**:
  - Small text clips & URLs (<3MB): Synchronized instantly via encrypted WebSocket payload events.
  - Large binary files (up to 50GB): Direct browser-to-browser WebRTC DataChannels using STUN/TURN ICE negotiation and local network direct peering. Zero intermediate cloud hosting or data snooping.
- **Data Retention & Privacy**: Sessions default to a 10-minute inactivity timer. Once expired, all messages, clip logs, and signaling states are wiped permanently.

## 2. Supported Platforms
- iOS and iPadOS (Safari, Chrome, Firefox)
- Android (Chrome, Samsung Internet, Firefox, Edge)
- Windows 10 and Windows 11 (Edge, Chrome, Firefox, Brave)
- macOS (Safari, Chrome, Firefox, Arc)
- Linux (Chrome, Firefox, Chromium)
- ChromeOS

## 3. Security & Safety Model
- No user accounts, passwords, email addresses, or phone numbers collected.
- Ephemeral 8-digit randomized room codes.
- Optional 4-digit room administrator PIN.
- Optional Host Approval queue ("Require Join Approval") preventing unauthorized room entry.
- Direct P2P WebRTC data transfer keeps file transfers confined to the local Wi-Fi / LAN when sender and receiver are on the same subnet.

## 4. Key Endpoints & Links
- [Online Clipboard](https://online-clipboard.site/): Primary web application interface.
- [Web App Manifest](https://online-clipboard.site/manifest.json): Progressive Web App manifest.
- [Agent Specification](https://online-clipboard.site/llms.txt): Machine-readable index for LLM agents.
- [Full Documentation](https://online-clipboard.site/llms-full.txt): Complete architectural overview.