What is macos-test-diagnoser?

A guide for diagnosing tests in macOS and Swift projects. It covers Xcode projects and Swift Package Manager, a tool used to build and test Swift packages.

Use it to choose a small test scope, run the appropriate command, classify failures, rerun focused cases, and report the next useful debugging step.

It helps separate code failures from build problems, crashes, timing issues, missing permissions, and test-environment problems.

macos-test-diagnoser — Skill for Claude Code and Codex by Xopoko

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 macos-test-diagnoser

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/xopoko/build-swift-apps/macos-test-diagnoser/github.svg)](https://agentmods.dev/skills/xopoko/build-swift-apps/macos-test-diagnoser)

Your own site

<a href="https://agentmods.dev/skills/xopoko/build-swift-apps/macos-test-diagnoser"><img src="https://agentmods.dev/badge/skills/xopoko/build-swift-apps/macos-test-diagnoser/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/xopoko/build-swift-apps/macos-test-diagnoser"><img src="https://agentmods.dev/badge/skills/xopoko/build-swift-apps/macos-test-diagnoser.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 47 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 670 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 pass 7 Sept 2026

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.

Model	Per session	Once invoked
Fable 5.1	$0.00047	$0.00670
Opus 5	$0.00023	$0.00335
Sonnet 5	$0.00009	$0.00134
Haiku 4.5	$0.00005	$0.00067

Measured 11d ago against content hash ad79bb1b9fc3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

macos-test-diagnoser 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 11d ago.

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/macos-test-diagnoser/SKILL.md · 73 lines

How it starts

The opening of the file, as written. The whole thing — 73 lines — stays where its author put it; the contents beside it link to each section on GitHub.

macOS Test Diagnoser

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.

Quick Start

Use this skill to run the smallest meaningful test scope first, classify failures precisely, and avoid treating every test failure like a product bug.

Workflow

Detect the test harness.
- Use xcodebuild test for Xcode-based projects.
- Use swift test for SwiftPM packages.
Narrow the scope.
- If the user gave a target, product, or test filter, use it.
- If not, prefer the smallest likely failing target before a full suite.
Classify the result.
- Build failure
- Assertion failure
- Crash or signal
- Async timing or flake
- Environment or fixture setup issue
- Missing entitlement or host app issue
Rerun intelligently.
- Use focused reruns when a specific case fails.
- Avoid burning time on full-suite reruns without new information.
Summarize clearly.
- What command ran
- Which tests failed
- What kind of failure it was
- The best next proof step or fix path

Result Bundle Inspection

When console output alone is not enough, read the .xcresult bundle instead of rerunning:

Pass -resultBundlePath ./Tests.xcresult to xcodebuild test so evidence lands at a known path.
Run summary: xcrun xcresulttool get test-results summary --path Tests.xcresult
Per-test outcomes: xcrun xcresulttool get test-results tests --path Tests.xcresult
One failure in depth: xcrun xcresulttool get test-results test-details --test-id <id> --path Tests.xcresult
Attachments such as screenshots and logs: xcrun xcresulttool export attachments --path Tests.xcresult --output-path ./attachments
Older bundles or full object graph: xcrun xcresulttool get --legacy --format json --path Tests.xcresult (drop --legacy on pre-Xcode 16 toolchains).

Read the full file on GitHub · 73 lines

Files

What ships with it

1 file 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.

agents/openai.yaml 327 B

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.

11d ago First seen · 73 lines · 47 tokens per session scan A ad79bb1b9fc3

Subscribe to this mod's changes

macos-test-diagnoser is a skill published in the GitHub repository Xopoko/build-swift-apps (45 stars, last pushed 13d ago), licensed MIT. It adds 47 tokens to every session and 670 once invoked, about $0.0002 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 2026-08-30.

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