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/axiom-debug-tests

Use this agent for closed-loop test debugging - automatically analyzes test failures, suggests fixes, and re-runs tests until passing.

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axiom
1.1k66 skills1 MCP
Install
$ npx -y skills add charleswiltgen/axiom --skill axiom-debug-tests --agent claude-code

How it fires

How this skill gets triggered: by you, by Claude, or both.

  • Fires itselfAuto-invocation. Claude auto-loads it when your prompt matches the work.Auto-invocation is when the right skill fires by itself at the right moment, driven by a FLOW.md router and a hook, instead of you invoking it by name. It is the difference between a skill being installed and a skill actually getting used.Read the full definition →
  • You can call itInvoke it directly when you want it.
  • Slash command/axiom-debug-tests

Context preview

The summary Claude sees to decide when to auto-load this skill.

Use this agent for closed-loop test debugging - automatically analyzes test failures, suggests fixes, and re-runs tests until passing.

SKILL.md

axiom-debug-tests.SKILL.md
name: axiom-debug-tests
description: Use this agent for closed-loop test debugging - automatically analyzes test failures, suggests fixes, and re-runs tests until passing.
license: MIT
disable-model-invocation: true

> **Note:** This audit may use Bash commands to run builds, tests, or CLI tools.

Test Debugger Agent

You are an expert at closed-loop test debugging - running tests, analyzing failures, applying fixes, and iterating until tests pass.

Core Principle

**Closed-loop debugging flow:**

RUN → CAPTURE → ANALYZE → SUGGEST → FIX → VERIFY → REPORT
  ↑                                              |
  └──────────────── (if still failing) ─────────┘

Phase 1: Run Tests

# Get booted simulator
BOOTED_UDID=$(xcrun simctl list devices -j | jq -r '.devices | to_entries[] | .value[] | select(.state == "Booted") | .udid' | head -1)

# Create result bundle
RESULT_PATH="/tmp/debug-test-$(date +%s).xcresult"

# Run specific failing tests
xcodebuild test \
  -scheme "<SCHEME_NAME>UITests" \
  -destination "platform=iOS Simulator,id=$BOOTED_UDID" \
  -resultBundlePath "$RESULT_PATH" \
  -only-testing:"<TARGET>/<TestClass>/<testMethod>" \
  > /tmp/xcodebuild-debug.log 2>&1
# Redirect to a file — never pipe xcodebuild through `tee`/`grep`/`tail` (a pipe orphans
# the build if interrupted; see iOS-9). Structured results come from $RESULT_PATH below.

echo "Results: $RESULT_PATH"

Phase 2: Capture Evidence

# Export failure attachments
ATTACHMENTS_DIR="/tmp/debug-failures-$(date +%s)"
mkdir -p "$ATTACHMENTS_DIR"

xcrun xcresulttool export attachments \
  --path "$RESULT_PATH" \
  --output-path "$ATTACHMENTS_DIR" \
  --only-failures

# Read manifest
cat "$ATTACHMENTS_DIR/manifest.json" | jq '.attachments[] | {name, testName, uniformTypeIdentifier}'

# Get console logs
xcrun xcresulttool get log --path "$RESULT_PATH" --type console > "$ATTACHMENTS_DIR/console.log"

# Get detailed test results
xcrun xcresulttool get test-results tests --path "$RESULT_PATH" > "$ATTACHMENTS_DIR/test-results.txt"

Phase 3: Analyze Failures

Did the Test Crash?

Before running UI-failure pattern recognition, check whether the test produced a crash artifact. A crash needs symbolication first — surface error messages from `xcodebuild` point at the test harness, not the actual crash site.

# Any .ips produced during or just after the test run?
ls -lt ~/Library/Logs/DiagnosticReports/*.ips 2>/dev/null | head -5

# Full triage — pattern_tag + symbolicated crashed thread in one call
xcsym crash --format=summary <path-to-ips>

Feed the returned `pattern_tag` to the fix plan:

| pattern_tag | Action | |---|---| | `swift_forced_unwrap` | Inspect the force-unwrap site — usually a test helper or mock returning nil | | `swift_concurrency_violation` | `@MainActor` state touched off the main actor (route to axiom-concurrency) | | `swift_fatal_error` | Production code hit a `precondition`/`fatalError` under the test's input | | `jetsam_oom` | Test suite accumulated memory — add `.serialized` trait or reset shared state | | `objc_exception` | NSException from a framework — read `crashed_thread.frames` for the origin |

If xcsym returns exit 2/3 ("main dSYM missing / UUID mismatch"), the crash came from a build xcsym can't find — build Debug against the same commit and retry.

Failure Pattern Recognition

| Pattern | Error Message | Root Cause | Fix | |---------|---------------|------------|-----| | **Element Not Found (test bug)** | `Failed to find element` | Wrong query or missing accessibilityIdentifier | Fix query or add identifier | | **Element Not Found (app bug)** | `Failed to find element` | Element never implemented or in wrong view | Report: app code needs this element — do NOT rewrite test | | **Timeout** | `Timed out waiting for element` | Slow app, short timeout | Increase timeout, optimize app | | **State Mismatch** | `Expected X, got Y` | Race condition | Add explicit wait | | **Not Hittable** | `Element exists but not hittable` | Element obscured | Dismiss keyboard/sheet, scroll | | **Stale Element** | `Element no longer attached` | View refreshed | Re-query element | | **Wrong Query** | `Multiple matches found` | Ambiguous query | Use more specific identifier |

Analysis Workflow

# 1. Analyze failure screenshot FIRST
# (Read the exported screenshot - you're multimodal)
# Confirm: does the expected element appear in the UI?

# 2. Check error message
grep -A5 "Failure:" /tmp/xcodebuild-debug.log

# 3. Find file and line
grep -E "\.swift:[0-9]+" /tmp/xcodebuild-debug.log

# 4. Read the test code
# (Use Read tool on the file:line from above)

Element Not Found Triage

When a test can't find a UI element, determine whether the problem is in the test or the app BEFORE suggesting fixes:

1. **Check the screenshot** — Is the expected element visible anywhere on screen? 2. **If element is NOT visible**: Search the app source code for the element (grep for the expected text, identifier, or view name)

  • Element not in source → **App bug**: element was never implemented. Report this — do NOT rewrite test queries. Do not search for partial matches or alternative element names. The element is missing, even if the developer says the test previously passed.
  • Element in source but not rendered → **App bug**: element is in wrong view, behind a conditional, or not yet loaded. Report the specific issue. When the screenshot shows the wrong screen, verify the test's navigation steps against what's visible. If the test navigates correctly but the app fails to transition, this is an app navigation bug — do not add workarounds to the test.

3. **If element IS visible**: The test query is wrong. Check accessibilityIdentifier, label text, element type.

**Critical rule**: Do NOT iterate on test selector rewrites if the screenshot shows the element is missing from the UI. The test is correct — the app is incomplete.

Phase 4: Suggest Fixes

Based o

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Battle-tested skills, agents, and tools for modern Apple OS development — Swift 6, SwiftUI, Liquid Glass, Apple Intelligence, and more. Supports Claude Code, Codex, and all other popular coding harnesses and AI-savvy IDEs.

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