home / skills / charleswiltgen / axiom / axiom-ios-testing
This skill helps you write faster, reliable iOS tests by routing questions to swift-testing, ui-testing, and async testing patterns.
npx playbooks add skill charleswiltgen/axiom --skill axiom-ios-testingReview the files below or copy the command above to add this skill to your agents.
---
name: axiom-ios-testing
description: Use when writing ANY test, debugging flaky tests, making tests faster, or asking about Swift Testing vs XCTest. Covers unit tests, UI tests, fast tests without simulator, async testing, test architecture.
license: MIT
---
# iOS Testing Router
**You MUST use this skill for ANY testing-related question, including writing tests, debugging test failures, making tests faster, or choosing between testing approaches.**
## When to Use
Use this router when you encounter:
- Writing new unit tests or UI tests
- Swift Testing framework (@Test, #expect, @Suite)
- XCTest or XCUITest questions
- Making tests run faster (without simulator)
- Flaky tests (pass sometimes, fail sometimes)
- Testing async code reliably
- Migrating from XCTest to Swift Testing
- Test architecture decisions
- Condition-based waiting patterns
## Routing Logic
This router invokes specialized skills based on the specific testing need:
### 1. Unit Tests / Fast Tests → **swift-testing**
**Triggers**:
- Writing new unit tests
- Swift Testing framework (`@Test`, `#expect`, `#require`, `@Suite`)
- Making tests run without simulator
- Testing async code reliably
- `withMainSerialExecutor`, `TestClock`
- Migrating from XCTest
- Parameterized tests
- Tags and traits
- Host Application: None configuration
- Swift Package tests (`swift test`)
**Why swift-testing**: Modern Swift Testing framework with parallel execution, better async support, and the ability to run without launching simulator.
**Invoke**: Read the `axiom-swift-testing` skill
---
### 2. UI Tests / XCUITest → **ui-testing**
**Triggers**:
- Recording UI Automation (Xcode 26)
- XCUIApplication, XCUIElement
- Flaky UI tests
- Tests pass locally, fail in CI
- `sleep()` or arbitrary timeouts
- Condition-based waiting
- Cross-device testing
- Accessibility-first testing
**Why ui-testing**: XCUITest requires simulator and has unique patterns for reliability.
**Invoke**: Read the `axiom-ui-testing` skill
---
### 3. Flaky Tests / Race Conditions → **test-failure-analyzer** (Agent)
**Triggers**:
- Tests fail randomly in CI
- Tests pass locally but fail in CI
- Flaky tests (pass sometimes, fail sometimes)
- Race conditions in Swift Testing
- Missing `await confirmation` for async callbacks
- Missing `@MainActor` on UI tests
- Shared mutable state in `@Suite`
- Tests pass individually, fail when run together
**Why test-failure-analyzer**: Specialized agent that scans for patterns causing intermittent failures in Swift Testing.
**Invoke**: Launch `test-failure-analyzer` agent
---
### 4. Async Testing Patterns → **testing-async**
**Triggers**:
- Testing async/await functions
- `confirmation` for callbacks (Swift Testing)
- `expectedCount` for multiple callbacks
- Testing MainActor code with `@MainActor @Test`
- Migrating XCTestExpectation → confirmation
- Parallel test execution concerns
- Test timeout configuration
**Why testing-async**: Dedicated patterns for async code in Swift Testing framework.
**Invoke**: Read the `axiom-testing-async` skill
---
### 5. Test Crashes / Environment Issues → **xcode-debugging**
**Triggers**:
- Tests crash before assertions run
- Simulator won't boot for tests
- Tests hang indefinitely
- "Unable to boot simulator" errors
- Clean test run differs from incremental
**Why xcode-debugging**: Test failures from environment issues, not test logic.
**Invoke**: Read the `axiom-xcode-debugging` skill
---
### 6. Running XCUITests from Command Line → **test-runner** (Agent)
**Triggers**:
- Run tests with xcodebuild
- Parse xcresult bundles
- Export failure screenshots/videos
- Code coverage reports
- CI/CD test execution
**Why test-runner**: Specialized agent for command-line test execution with xcresulttool parsing.
**Invoke**: Launch `test-runner` agent
---
### 7. Closed-Loop Test Debugging → **test-debugger** (Agent)
**Triggers**:
- Fix failing tests automatically
- Debug persistent test failures
- Run → analyze → fix → verify cycle
- Need to iterate until tests pass
- Analyze failure screenshots
**Why test-debugger**: Automated cycle of running tests, analyzing failures, suggesting fixes, and re-running.
**Invoke**: Launch `test-debugger` agent
---
### 8. Recording UI Automation (Xcode 26) → **ui-recording**
**Triggers**:
- Record user interactions in Xcode
- Test plans for multi-config replay
- Video review of test runs
- Xcode 26 recording workflow
- Enhancing recorded test code
**Why ui-recording**: Focused guide for Xcode 26's Record/Replay/Review workflow.
**Invoke**: Read the `axiom-ui-recording` skill
---
### 9. UI Automation Without XCUITest → **simulator-tester** + **axe-ref**
**Triggers**:
- Automate app without test target
- AXe CLI usage (tap, swipe, type)
- describe-ui for accessibility tree
- Quick automation outside XCUITest
- Scripted simulator interactions
**Why simulator-tester + axe-ref**: AXe provides accessibility-based UI automation when XCUITest isn't available.
**Invoke**: Launch `simulator-tester` agent (uses axiom-axe-ref)
---
## Decision Tree
1. Writing unit tests / Swift Testing? → swift-testing
2. Writing UI tests / XCUITest? → ui-testing
3. Testing async/await code? → testing-async
4. Flaky tests / race conditions (XCUITest)? → ui-testing
5. Flaky tests / race conditions (Swift Testing)? → test-failure-analyzer (Agent)
6. Tests crash / environment wrong? → xcode-debugging (via ios-build)
7. Tests are slow? → swift-testing (Fast Tests section)
8. Run tests from CLI / parse results? → test-runner (Agent)
9. Fix failing tests automatically? → test-debugger (Agent)
10. Record UI interactions (Xcode 26)? → ui-recording
11. Automate without XCUITest / AXe CLI? → simulator-tester + axe-ref
## Swift Testing vs XCTest Quick Guide
| Need | Use |
|------|-----|
| Unit tests (logic, models) | Swift Testing |
| UI tests (tap, swipe, assert screens) | XCUITest (XCTest) |
| Tests without simulator | Swift Testing + Package/Framework |
| Parameterized tests | Swift Testing |
| Performance measurements | XCTest (XCTMetric) |
| Objective-C tests | XCTest |
## Anti-Rationalization
| Thought | Reality |
|---------|---------|
| "Simple test question, I don't need the skill" | Proper patterns prevent test debt. swift-testing has copy-paste solutions. |
| "I know XCTest well enough" | Swift Testing is significantly better for unit tests. swift-testing covers migration. |
| "Tests are slow but it's fine" | Fast tests enable TDD. swift-testing shows how to run without simulator. |
| "I'll fix the flaky test with a sleep()" | sleep() makes tests slower AND flakier. ui-testing has condition-based waiting patterns. |
| "I'll add tests later" | Tests written after implementation miss edge cases. swift-testing makes writing tests first easy. |
## Example Invocations
User: "How do I write a unit test in Swift?"
→ Invoke: axiom-swift-testing
User: "My UI tests are flaky in CI"
→ Check codebase: XCUIApplication/XCUIElement patterns? → ui-testing
→ Check codebase: @Test/#expect patterns? → test-failure-analyzer
User: "Tests fail randomly, pass sometimes fail sometimes"
→ Invoke: test-failure-analyzer (Agent)
User: "Tests pass locally but fail in CI"
→ Invoke: test-failure-analyzer (Agent)
User: "How do I test async code without flakiness?"
→ Invoke: testing-async
User: "How do I test callback-based APIs with Swift Testing?"
→ Invoke: testing-async
User: "What's the Swift Testing equivalent of XCTestExpectation?"
→ Invoke: testing-async
User: "How do I use confirmation with expectedCount?"
→ Invoke: testing-async
User: "I want my tests to run faster"
→ Invoke: axiom-swift-testing (Fast Tests section)
User: "Should I use Swift Testing or XCTest?"
→ Invoke: axiom-swift-testing (Migration section) + this decision tree
User: "Tests crash before any assertions"
→ Invoke: axiom-xcode-debugging
User: "Run my tests and show me what failed"
→ Invoke: test-runner (Agent)
User: "Help me fix these failing tests"
→ Invoke: test-debugger (Agent)
User: "Parse the xcresult from my last test run"
→ Invoke: test-runner (Agent)
User: "Export failure screenshots from my tests"
→ Invoke: test-runner (Agent)
User: "How do I record UI automation in Xcode 26?"
→ Invoke: axiom-ui-recording
User: "How do I use test plans for multi-language testing?"
→ Invoke: axiom-ui-recording
User: "Can I automate my app without writing XCUITests?"
→ Invoke: simulator-tester (Agent) + axiom-axe-ref
User: "How do I tap a button using AXe?"
→ Invoke: axiom-axe-ref (via simulator-tester)
This skill routes any iOS/xOS testing question to the right testing workflow or agent. It covers unit tests, UI tests, flaky test diagnosis, async testing patterns, fast tests without a simulator, and test-run tooling for CI. Use it as the single entry point for decisions between Swift Testing and XCTest and for invoking specialized tools for debugging or automation.
The router inspects your testing intent and environment and then delegates to a focused skill or agent. It matches topics like Swift Testing annotations, XCUITest patterns, flaky failures, async/await needs, simulator issues, and CLI xcresult handling, then invokes the recommended helper (swift-testing, ui-testing, testing-async, test-failure-analyzer, xcode-debugging, test-runner, test-debugger, etc.). Follow its decision tree to get targeted guidance or automated analysis.
Should I always use Swift Testing instead of XCTest?
Use Swift Testing for unit, logic, and fast host tests; use XCTest/XCUITest when you must interact with the app UI or need platform-specific metrics.
My tests are flaky—what is the first step?
Run the test-failure-analyzer agent to look for common race conditions, missing awaits, shared state, or MainActor issues before adding waits or timeouts.