| name | apple-preview-browser |
| description | Mirror iOS Simulator into the Codex in-app browser and render SwiftUI package previews with hot reload. Use when the user needs browser-visible Simulator proof, interactive iOS app viewing, SwiftUI preview iteration outside Xcode Canvas, or screenshot evidence from the Codex browser. |
Apple Preview Browser
Purpose
Use this skill when the user needs to see or interact with an iOS Simulator or SwiftUI previews inside the Codex browser. This is proof tooling, not a substitute for a real app build.
Use apple-build-run-debug first when the app is not built, launched, or assigned to a known Simulator UDID.
Simulator Mirror Workflow
- Obtain an explicit Simulator UDID from XcodeBuildMCP or
DEVELOPER_DIR=<path> xcrun simctl list devices available.
- Start
serve-sim in a long-running terminal scoped to that UDID.
SIM="<simulator-udid>"
cleanup_serve_sim() {
npx --yes serve-sim@latest --kill "$SIM" >/dev/null 2>&1 || true
}
trap cleanup_serve_sim EXIT INT TERM HUP
cleanup_serve_sim
npx --yes serve-sim@latest "$SIM"
- Open the exact local URL printed by
serve-sim in the Codex in-app browser.
- Verify a real simulator frame is rendering before reporting success.
- When finished, stop the terminal and wait for the trap to clean up the scoped helper.
Never run an unscoped serve-sim --kill; another thread may own a different simulator mirror.
SwiftUI Preview Workflow
Use the bundled launcher for importable Swift packages:
node <skill-root>/scripts/swiftui-preview-browser.mjs \
/absolute/path/to/Package.swift \
--package-target "<target>" \
--device "<simulator-udid>"
The launcher creates a disposable host outside the user's source tree, installs and launches it in Simulator, and watches package edits. Use --preview-filter <regex[, ...]> to show a subset.
Once the launcher prints the selected Simulator UDID, start serve-sim for that same UDID and open the printed URL.
Boundaries
- Support Swift Package-backed
PreviewProvider and #Preview declarations.
- Do not edit the user's
.xcodeproj, .xcworkspace, Package.swift, schemes, or build settings to force preview support.
- Do not claim browser proof from a loaded page alone; verify pixels or capture a screenshot of the simulator frame.
Bundled Scripts
scripts/swiftui-preview-browser.mjsscripts/lib/xcode-project.mjsscripts/templates/
