iOS Simulator Browser

Use serve-sim as the shared visual feed for an iOS Simulator. Use ios-debugger-agent and XcodeBuildMCP semantic UI tools to drive the app; do not treat browser-canvas coordinates as a substitute for missing app accessibility.

Confirm availability

serve-sim 0.1.45 requires Apple Silicon macOS, Xcode command-line tools, and Node.js 20 or newer. If the host is unsupported, continue with XcodeBuildMCP screenshots and report that live streaming was unavailable.

When running inside T3 Code, use its product-native browser MCP to open the stream. Other agent hosts may use their own browser or preview surface.

Keep serve-sim on its default 127.0.0.1 binding. Do not expose its preview to a LAN or tunnel unless the user explicitly requests that access and the network is trusted; the preview includes a token-gated shell-execution route.

Start one owned stream

1. Obtain the exact simulator UDID from the iOS build or launch workflow.

2. Check whether an existing serve-sim stream for that UDID belongs to another task. Reuse it only when explicitly shared; never kill another task's stream.

3. Otherwise, clear only a stale stream for that UDID and start the pinned version with scoped cleanup:

   SIMULATOR_ID=<simulator-udid>
   cleanup_serve_sim() {
     npx --yes serve-sim@0.1.45 --kill "$SIMULATOR_ID" >/dev/null 2>&1 || true
   }
   trap cleanup_serve_sim EXIT INT TERM HUP
   cleanup_serve_sim
   npx --yes serve-sim@0.1.45 "$SIMULATOR_ID"
   

4. Keep the terminal alive and open the exact local URL printed by serve-sim in the agent's browser.

5. Verify that a live simulator frame renders. A loaded wrapper page is not sufficient evidence.

Observe while driving semantically

• Let the user watch the serve-sim stream while XcodeBuildMCP performs snapshot_ui, semantic taps, typing, gestures, and screenshots.
• Keep the browser and Xcode tooling pinned to the same simulator UDID.
• Do not switch to generic desktop automation or browser-canvas clicking merely because the stream is visible.

If the in-app browser explicitly reports that previews are unavailable, do not install unrelated browser automation. Continue through XcodeBuildMCP, capture a simulator screenshot, report the unavailable live stream, and clean up the owned serve-sim process.

Finish

Stop the long-running terminal and wait for its cleanup trap to finish. If it disappeared without cleanup, run npx --yes serve-sim@0.1.45 --kill <simulator-udid> for that exact simulator. Never run an unscoped --kill.

Upstream

Adapted from OpenAI's build-ios-apps plugin version 0.1.2 (ios-simulator-browser, MIT). It invokes serve-sim 0.1.45 under its Apache-2.0 license without vendoring the package.