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The isConnected() method provides a quick way to verify whether your current sandbox instance is actively connected to Fermion’s infrastructure. It returns a simple boolean value : true if the WebSocket connection is established and ready for commands, or false if the sandbox has been disconnected, has not yet been created, or encountered a network interruption. This method is especially useful for implementing connection health checks, conditional command execution, or automatic reconnection logic in your application. You can safely call isConnected() at any time without throwing errors, making it ideal for lightweight status polling and runtime monitoring.

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isConnected()

Description: Checks if the WebSocket connection to the sandbox is currently active. Parameters: None Returns: boolean - true if connected, false otherwise Example: 
console.log(sandbox.isConnected()) // false

await sandbox.create({ shouldBackupFilesystem: false })
console.log(sandbox.isConnected()) // true

await sandbox.disconnect()
console.log(sandbox.isConnected()) // false
Use Cases: 
// Conditional operations
if (sandbox.isConnected()) {
  await sandbox.runCommand({ cmd: 'ls' })
} else {
  console.log('Not connected. Call create() first.')
}

// Health check
setInterval(() => {
  if (!sandbox.isConnected()) {
    console.warn('Sandbox disconnected!')
  }
}, 5000)