xcode-ui-test-stabilizer

xcode-ui-test-stabilizer is a skill for Claude Code, Codex from Xopoko/build-swift-apps. It costs 51 tokens per session (550 once invoked), scanned A, original, MIT.

A method for creating and stabilizing Xcode UI end-to-end tests that drive an app as a user would.

In plain words
What is it for?
It helps define success signals, configure test-only behavior, use accessibility identifiers, wait for UI states, and collect logs and screenshots.
Why use it?
It reduces flaky tests caused by unstable identifiers, unreliable input, missing waits, environment differences, or poor failure evidence.

Skill for Claude CodeCodex

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also agents/openai.yaml present.

Part of the build-swift-apps plugin — 61 skills, 3 commands, 3 MCP servers shipped together

Good fit It helps define success signals, configure test-only behavior, use accessibility identifiers, wait for UI states, and collect logs and screenshots.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/xopoko/build-swift-apps/xcode-ui-test-stabilizer
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add Xopoko/build-swift-apps --skill xcode-ui-test-stabilizer
Clone the repo
git clone --depth 1 https://github.com/Xopoko/build-swift-apps

Made for: Claude Code, Codex.

Or install build-swift-apps, the plugin that ships this one along with the rest of its 61 skills, 3 commands, 3 MCP servers.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for xcode-ui-test-stabilizer

README.md
[![agentmods](https://agentmods.dev/badge/skills/xopoko/build-swift-apps/xcode-ui-test-stabilizer/github.svg)](https://agentmods.dev/skills/xopoko/build-swift-apps/xcode-ui-test-stabilizer)
Your own site
<a href="https://agentmods.dev/skills/xopoko/build-swift-apps/xcode-ui-test-stabilizer"><img src="https://agentmods.dev/badge/skills/xopoko/build-swift-apps/xcode-ui-test-stabilizer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for xcode-ui-test-stabilizer

Your own site · 80×15
<a href="https://agentmods.dev/skills/xopoko/build-swift-apps/xcode-ui-test-stabilizer"><img src="https://agentmods.dev/badge/skills/xopoko/build-swift-apps/xcode-ui-test-stabilizer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 51 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 550 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 2 findings, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high Privilege Escalation · line 55
    Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.
    Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
  • medium Excessive Agency · line 27
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00051 $0.00550
Opus 5 $0.00026 $0.00275
Sonnet 5 $0.00010 $0.00110
Haiku 4.5 $0.00005 $0.00055

Measured 7d ago against content hash cda6ca2d4039, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

xcode-ui-test-stabilizer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 7d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/run_ui_test.sh), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/xcode-ui-test-stabilizer/SKILL.md · 60 lines

How it starts

The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Xcode UI Test Stabilizer

Before invoking Apple-only binaries, confirm the execution context is macOS. From Windows or Linux, run those steps in a Mac SSH project or through an already configured remote transport; do not retry missing Apple binaries locally.

Overview

Build deterministic UI end-to-end tests and debug flaky runs. Prefer stable accessibility identifiers, environment-driven setup, and explicit wait conditions. Always attach logs and screenshots on failure.

Workflow

  1. Define the flow and success signals.

    • Identify the UI state that proves success (accessibility identifiers, log markers, or system-visible views).
    • Decide which logs to capture (app log, build log, UI test log).
  2. Add or update the UI test.

    • Use stable identifiers (avoid labels that can change or be localized).
    • Avoid typing into complex text components when possible; prefer injecting text via test-only defaults.
    • Gate test-only behavior behind env flags so production behavior is unchanged.
  3. Stabilize the app for UI tests.

    • Ensure the app activates and brings windows to front in UI test mode.
    • Disable modal blockers or auto-approve when tests run.
    • Use in-memory persistence for tests if persistent stores are fragile.
  4. Run the test with the provided script or your own command.

    • Use scripts/run_ui_test.sh (from this skill) or run xcodebuild test with -only-testing.
  5. Triage failures.

    • Attach logs and screenshots.
    • Search logs for build/preview errors and unexpected user-stop messages.
    • Iterate until the test is deterministic.

Stability checklist (quick wins)

  • Use waitForExistence for every critical element.
  • Assert the app is running foreground before input.
  • Avoid typeText for long text; prefer env-injected defaults.
  • Click the window before interacting.
  • Keep timeouts explicit and generous for CI machines.
  • Attach logs and screenshots on failure.

References

  • Read references/ui-e2e-playbook.md for generic flags, focus fixes, typing workarounds, and debugging patterns.

Read the full file on GitHub · 60 lines

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 7d ago First seen · 60 lines · 51 tokens per session scan A cda6ca2d4039

Subscribe to this mod's changes

xcode-ui-test-stabilizer is a skill published in the GitHub repository Xopoko/build-swift-apps (45 stars, last pushed 13d ago), licensed MIT. It adds 51 tokens to every session and 550 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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