The iOS Simulator for coding agents.

Name: simulator-use
Author: NoMac

Claude Code, Codex, Cursor or any MCP client builds your app, reads the screen as text and taps by label. Free and open source.

$ claude mcp add simulator-use -- npx -y simulator-use mcp

View on GitHub

what the agent readsMCP

0.28 sto read a whole screen

70 tokensfor that screen

<1 msto send a tap

846npm downloads last week

One engine per Simulator.

It keeps the input, the accessibility session and the screen buffer open. A tool that starts a helper for every call pays for them every time.

Read the screenui_look

0.28 s

1.45 s per helper

Read it with a screenshotui_look screenshot

0.35 s

1.62 s per helper

Tap, wait, read what changedui_act tap "Settings"

1.58 s

5.97 s per helper

Send a tapthe input alone

<1 ms

2.6 s per helper

The same tools with the engine on and off (off: AXe 1.8.0, one process per call). Apple M6 Mac mini, iOS 27.0, October 21, 2026. Scripts in native/engine/bench.

A whole agent run: 67 seconds, 808 tokens.

Twelve tasks on the demo app, from a fresh phone to a failing sign-in. Rerun it with scripts/golden-cloud.mjs.

Task	Seconds	Tokens
A cloud phone, ready	2.71	0
The project from git	5.34	19
Build, install and launch	15.18	89
Read the screen	0.61	71
Sign in and wait for "Welcome"	6.75	29
Toggle a switch	2.75	14
Open an item	4.32	49
Back and scroll	5.59	138
The app's print output	0.46	122
Find a crash as file:line	2.10	142
Run 3 XCTests	9.49	12
A wrong password fails loudly	11.96	123
12 of 12 passed	67.3	808

On a NoMac cloud phone, October 24, 2026. Tokens are what the agent reads back.

Tools

One list for MCP and the CLI. Every step is checked: typed text is read back, and a tap that changes nothing says so.

app_run

Build, install and launch. Errors as file:line.

ui_look

The screen as text. A screenshot, or a full-size PNG.

ui_act

Tap, fill, scroll, swipe, wait. Answers with what changed.

tests_run

XCTest and XCUITest, case by case.

app_control

Install, deep links, permissions, location, push, locale.

app_logs

Print output, system logs and crashes.

screen_record

A video of the screen.

devices, device_use

Pick and boot a Simulator.

job_status, job_cancel

Follow or stop a long build.

cloud

Run every tool on a cloud iPhone instead.

Install

Needs a Mac with Xcode and Node 20. Nothing leaves your Mac unless you turn on cloud.

Add to Cursor Add to VS Code

claude mcp add simulator-use -- npx -y simulator-use mcp

codex mcp add simulator-use -- npx -y simulator-use mcp

{
  "mcpServers": {
    "simulator-use": { "command": "npx", "args": ["-y", "simulator-use", "mcp"] }
  }
}

npx simulator-use look
npx simulator-use act 'fill #email gary@example.com' 'tap #signIn'

No Mac? Use a cloud iPhone.

The same tools from Linux, Windows or CI, on an iPhone Simulator run by NoMac.

npx simulator-use cloud start
npx simulator-use run      # send, build, launch
npx simulator-use look
npx simulator-use cloud stop

# CI in one line
npx simulator-use cloud run . --tests

$0.80 an hour, by the minute. No subscription.
Only changed files are sent; builds stay incremental.
A live link to watch the phone, and a replay for 7 days.
A GitHub Action that tests each pull request.

nomac.app/simulator