orca/skill-guides/orca-emulator.md

name, description, license

name	description	license
orca-emulator	iOS Simulator control from inside Orca, with the live device view in Orca's emulator pane. Use when driving a booted Apple Simulator on macOS: taps, gestures, typing, hardware buttons, rotation, and the accessibility tree, or when an iOS change needs simulator evidence. For an Android device or emulator use the Android emulator skill; build and install the app with xcodebuild or simctl first.	Apache-2.0

Orca Emulator (iOS)

ORCA is a placeholder for the executable you resolved in the stub; substitute it before running.

Command surface

ORCA emulator --help lists the wrapped verbs. Anything else goes through ORCA emulator exec --command "<serve-sim command>", which forwards the string to serve-sim unvalidated with the active device injected.

install, launch, permissions, and logcat are Android-only and fail against an iOS device with emulator_unsupported. tap, type, gesture, button, rotate, ax, and exec work on both backends.

Commands drive devices on the host that runs the Orca runtime. Simulators need that host to be a Mac, so a Linux orca serve or SSH host can drive only Android devices.

Prerequisites

• macOS with the Xcode Command Line Tools (xcrun --version).
• A booted simulator (xcrun simctl list devices booted), or let attach boot one.
• An active session for the worktree before any input verb: run ORCA emulator attach or open the emulator pane.
• In a pnpm dev checkout, run pnpm build:cli before the first emulator command so the dev CLI shim reaches this worktree's runtime instead of a packaged install.

Orca reports a clear error when the host is missing macOS or the Xcode tools.

Operations

Use --json for agent-driven calls. Unqualified commands target the worktree's active device.

Goal	Command	Constraint
List available / running	ORCA emulator list --json	Orca-managed sessions plus raw serve-sim streams. Use its ids for --device / --emulator.
List devices everywhere	ORCA emulator devices --json	Every backend's devices with a platform column, booted and shutdown.
Attach / make active	ORCA emulator attach "iPhone 16 Pro" --json	Starts the helper if needed and makes the device active for the worktree. --focus switches the UI; it does not by default.
Single tap	ORCA emulator tap <x> <y> --json	Normalized 0..1 coordinates.
Multi-step gesture	ORCA emulator gesture '<json>' --json	Begin/move/end points. Use tap for a single tap.
Type text	ORCA emulator type "text" --json	US-ASCII only.
Hardware button	ORCA emulator button home --json	home and side_button are documented by the CLI spec; other names such as swipe_home, app_switcher, lock, and siri are forwarded to serve-sim unvalidated.
Rotate device	ORCA emulator rotate landscape_left --json	The orientation persists for subsequent gestures.
Accessibility tree	ORCA emulator ax --json	serve-sim node tree, capped at 500 nodes, frames normalized 0..1 with a top-left origin. Needs an active session.
Raw passthrough	ORCA emulator exec --command "ca-debug blended on" --json	serve-sim subcommand string, without a serve-sim prefix.
Stop the helper	ORCA emulator kill --json	Leaves the device booted.
Stop and power off	ORCA emulator shutdown --json	Stops the helper and shuts the simulator device down.

Targeting

attach, or opening the emulator pane, makes one device active per worktree, and unqualified commands target it. Pass a selector only to override that or reach a second device. With no active session an unqualified command fails with emulator_no_active; attach or open the pane and retry.

• --device "iPhone 16 Pro" or --device <udid>, from list or devices. --emulator <id> is an alternative spelling: the bridge resolves both through the same lookup. These selectors apply to the action verbs; list and devices take only --worktree, and attach names its device as a positional argument.
• --worktree id:<fullWorktreeId> or --worktree active. The full id is the exact <repo-id>::<path> value returned by ORCA worktree list --json; a bare repo id is not valid here.
• --worktree all drops worktree scoping on every verb, not only on listing, so a mutating command passed all runs unscoped. Use it only for listing.

Constraints

• All coordinates are normalized 0..1 with a top-left origin, never pixels. Tap an ax element at its frame center: x + width / 2, y + height / 2.
• Prefer tap over gesture for a single tap. A separate gesture begin/end pair can be interpreted as a long press because of WebSocket overhead; tap sends the quick sequence.
• type sends US-ASCII only, and unsupported characters error rather than degrading.
• The pane and the CLI share one stream and one helper, so closing the pane can stop the stream.
• Run kill when you are done. A helper left running holds the device until Orca quits.
• The iOS backend drives private simulator APIs, so an Xcode update can change its behavior.

Examples

ORCA emulator list --json
ORCA emulator attach "iPhone 16 Pro" --json
ORCA emulator tap 0.5 0.8 --json
ORCA emulator type "user@example.com" --json
ORCA emulator button home --json
ORCA emulator ax --json
ORCA emulator exec --command "ca-debug blended on" --json
ORCA emulator kill --device "iPhone 16 Pro" --json

See also: orca-emulator-android for Android devices, orca-cli for terminals, worktrees, and the built-in browser, and computer-use for desktop UI outside the simulator.