A lightweight, browser-based code editor inspired by VS Code — with an integrated AI copilot, live preview, and file management. Built entirely with a single HTML file.
- VS Code-inspired UI — Activity bar, sidebar explorer, tab bar, status bar & menu bar
- Monaco Editor — The same editor that powers VS Code, with syntax highlighting, IntelliSense and minimap
- AI Copilot — Integrated chat assistant powered by Claude (Anthropic) or Gemini (Google)
- Plan Mode — AI analyzes and plans without touching files
- Act Mode — AI creates, reads, edits, deletes and renames files autonomously
- YOLO Mode — AI executes all file operations automatically without asking for confirmation
- Live Preview — Full-screen browser preview for HTML files with automatic CSS/JS injection
- YOLO Live Preview — Side-by-side live preview panel that auto-refreshes on every change
- Browser Console Reader — AI can read the JS console output of the preview to detect and fix errors
- Version History — Automatic snapshots before every AI file modification with one-click restore
- ZIP Import / Export — Save your entire project as a
.zipor load one from disk - LocalStorage Persistence — All files are automatically saved in the browser
- Multiple AI Models — Choose between Claude Opus, Claude Sonnet, Gemini 2.5 Pro, Gemini 3 Flash and more
- Token & Cost Tracking — Real-time context usage (%) and estimated API cost display
| Requirement | Details |
|---|---|
| Modern Browser | Chrome, Edge or Firefox (for the editor & Gemini) |
| PHP 7.4+ with cURL | Only required for the Claude proxy backend |
Gemini works directly in the browser — no backend needed. The PHP backend is only required for Claude due to CORS restrictions of the Anthropic API.
- Clone or download this repository
- Open
index.htmlin any modern browser - Enter your Gemini API Key (
AIza...) — works immediately, no backend needed - OR for Claude: Deploy
backend.phpon a PHP server with cURL enabled, update the endpoint URL inindex.html, then enter your Claude API Key (sk-ant-...) - Start coding — or just type a request to the AI Copilot!
No build step, no npm, no complex setup. The frontend runs entirely in the browser.
Claude's API does not support direct browser requests due to CORS restrictions. A lightweight PHP proxy is included to solve this.
<?php
while (ob_get_level()) {
ob_end_clean();
}
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST, OPTIONS');
header('Access-Control-Allow-Headers: Content-Type, X-API-Key');
header('Content-Type: text/event-stream');
header('Cache-Control: no-cache');
header('Connection: keep-alive');
header('X-Accel-Buffering: no');
if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
exit(0);
}
$API_KEY = $_SERVER['HTTP_X_API_KEY'] ?? '';
if (empty($API_KEY)) {
echo "data: " . json_encode(['error' => 'API-Key missing!']) . "\n\n";
exit;
}
$input = file_get_contents('php://input');
$ch = curl_init('https://api.anthropic.com/v1/messages');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, false);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $input);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
'x-api-key: ' . $API_KEY,
'anthropic-version: 2023-06-01',
'content-type: application/json'
]);
curl_setopt($ch, CURLOPT_WRITEFUNCTION, function($curl, $data) {
echo $data;
if (ob_get_level() > 0) ob_flush();
flush();
return strlen($data);
});
$result = curl_exec($ch);
if ($result === false) {
$error_msg = curl_error($ch);
echo "data: " . json_encode(['error' => 'CURL-Error: ' . $error_msg]) . "\n\n";
} else {
$http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
if ($http_code >= 400) {
// ...
}
}
curl_close($ch);
?>- Upload
backend.phpto any PHP-enabled web server (e.g. Apache, Nginx, shared hosting) - Make sure cURL is enabled in your PHP installation
- In
index.html, find the following line and replace the URL with your server's URL:const response = await fetch("https://example.com/claude/backend.php", {
- Done — enter your Claude API Key in the editor and start using Claude!
⚠️ The backend acts as a pure pass-through proxy. Your API key is sent from the browser directly to your own server via HTTPS and forwarded to Anthropic. It is never logged or stored by the proxy.
The AI analyzes your request and proposes a plan — without modifying any files. Switch to Act Mode when you're ready to implement.
The AI uses tools to directly create, edit, rename or delete files. Each action requires your confirmation (unless YOLO Mode is enabled).
Enable the YOLO toggle to let the AI execute all file operations automatically. A live preview panel opens on the left for instant visual feedback.
| Extension | Language |
|---|---|
.html |
HTML |
.css |
CSS |
.js |
JavaScript |
.json |
JSON |
.md |
Markdown |
.txt |
Plaintext |
| Provider | Where to get | Runs without backend? |
|---|---|---|
| Claude | console.anthropic.com | ❌ No (PHP proxy needed) |
| Gemini | aistudio.google.com | ✅ Yes |
API keys are stored locally in your browser's localStorage and are never sent anywhere except to your own backend (Claude) or directly to Google (Gemini).
💡 Pro Tip: You can also use Ollama, LM Studio or any other OpenAI-compatible provider — you just need to adjust the API call in the code.
index.html ← The entire frontend application (HTML + CSS + JS)
backend.php ← Lightweight PHP proxy for the Claude API (CORS fix)
| Shortcut | Action |
|---|---|
Enter |
Send message to AI |
Shift + Enter |
New line in AI input |
Escape |
Close preview / modal |
- Monaco Editor
v0.45.0 - Font Awesome
v7.0.1 - JSZip
v3.10.1
MIT License — feel free to use, modify and distribute.