stablyai/orca · error · EmulatorError

emulator_device_not_found

emulator_device_not_found

Error message

Simulator ${udid} not found. Create one via Xcode > Window > Devices and Simulators.

What it means

ensureSimulatorBooted lists devices via simctl and the requested udid is not among them. The simulator must already exist before it can be booted; Orca does not create devices implicitly.

Source

Thrown at src/main/emulator/simctl-simulator-devices.ts:134

      if (typeof device === 'string' && device.toLowerCase().includes(deviceOrName.toLowerCase())) {
        return device
      }
    }
  } catch {}
  return deviceOrName
}

export async function ensureSimulatorBooted(udid: string): Promise<void> {
  if (platform() !== 'darwin') {
    throw new EmulatorError(
      'emulator_not_macos',
      'iOS Simulator requires macOS with Xcode Command Line Tools.'
    )
  }
  const devices = await listSimulatorDevices()
  const device = devices.find((candidate) => candidate.udid === udid)
  if (!device) {
    throw new EmulatorError(
      'emulator_device_not_found',
      `Simulator ${udid} not found. Create one via Xcode > Window > Devices and Simulators.`
    )
  }
  if (device.state === 'Booted') {
    return
  }

  try {
    await new Promise<void>((resolve, reject) => {
      execFile('xcrun', ['simctl', 'boot', udid], { timeout: 45_000 }, (error, _stdout, stderr) => {
        if (error) {
          const message = error.message.toLowerCase()
          if (message.includes('booted') || message.includes('current state')) {
            resolve()
            return
          }
          reject(mapSimctlError(error, stderr))

View on GitHub (pinned to 1136503c6a)

Solutions

Create the simulator in Xcode > Window > Devices and Simulators, or `xcrun simctl create <name> <type>`.
Copy the udid exactly from `xcrun simctl list devices`.
Run `xcode-select -p` to confirm the expected Xcode is active.

Example fix

// before
await ensureSimulatorBooted('BOGUS-UDID')

// after
const devices = await listSimulatorDevices()
if (!devices.some((d) => d.udid === udid)) {
  throw new Error(`Create ${udid} first: xcrun simctl create ...`)
}
await ensureSimulatorBooted(udid)

Defensive patterns

Strategy: validation

Validate before calling

const devices = await listSimulatorDevices()
if (!devices.some((d) => d.udid === udid)) { /* create device or fix udid */ }

Type guard

function isEmulatorError(e: unknown, code = 'emulator_device_not_found'): e is import('./emulator-errors').EmulatorError {
  return e instanceof Error && (e as any).code === code && e.name === 'EmulatorError'
}

Try / catch

try { await ensureSimulatorBooted(udid) }
catch (e) { if (isEmulatorError(e, 'emulator_device_not_found')) { udid = await pickOrCreateSimulator() } else throw e }

Prevention

Copy udids from `xcrun simctl list devices`.
Create devices via Xcode or `xcrun simctl create` before scripting.
Confirm the active Xcode with `xcode-select -p`.

When it happens

Trigger: listSimulatorDevices().find(candidate => candidate.udid === udid) returns undefined (simctl-simulator-devices.ts:131-137).

Common situations: udid typo; the device was erased/deleted; a fresh Xcode install with no simulators; the wrong Xcode is active (xcode-select).

Related errors

AI-assisted analysis of stablyai/orca@1136503c6a (2026-08-12). Data as JSON: /api/errors/64783d09cf004308. Report an issue: GitHub.