macos-development

macos-development is a skill for Claude Code, Codex from patrickserrano/lacquer. It costs 154 tokens per session (1,548 once invoked), scanned A, original, MIT.

A guide to the macOS platform APIs used to build apps with AppKit and SwiftUI. It covers macOS-specific behaviour such as multiple windows, menus, focus, sandbox permissions, and screen capture.

In plain words
What is it for?
Use it to build or debug macOS windows, menu bar commands, keyboard shortcuts, AppKit bridges, sandbox entitlements, and screen capture.
Why use it?
It helps explain why code that works on iOS or in Xcode can fail in a shipped macOS app, especially around window state, menu commands, and file access.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to build or debug macOS windows, menu bar commands, keyboard shortcuts, AppKit bridges, sandbox entitlements, and screen capture.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/patrickserrano/lacquer/macos-development
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 patrickserrano/lacquer --skill macos-development
Clone the repo
git clone --depth 1 https://github.com/patrickserrano/lacquer

Made for: Claude Code, Codex.

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 macos-development

README.md
[![agentmods](https://agentmods.dev/badge/skills/patrickserrano/lacquer/macos-development.svg)](https://agentmods.dev/skills/patrickserrano/lacquer/macos-development)
Your own site
<a href="https://agentmods.dev/skills/patrickserrano/lacquer/macos-development"><img src="https://agentmods.dev/badge/skills/patrickserrano/lacquer/macos-development.svg" alt="Measured on agentmods" height="20"></a>
Per session 154 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,548 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.
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 $0.00154 $0.01548
Opus 5 $0.00077 $0.00774
Sonnet 5 $0.00031 $0.00310
Haiku 4.5 $0.00015 $0.00155

Measured 3d ago against content hash f5d1f34f60b5, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

macos-development 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 3d 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.

profiles/ios/skills/macos-development/SKILL.md · 86 lines

How it starts

The opening of the file, as written. The whole thing — 86 lines — stays where its author put it; the contents beside it link to each section on GitHub.

macOS Development

Platform mechanics for macOS apps — windows, menus, sandboxing, AppKit bridging, ScreenCaptureKit, and where SwiftUI on macOS diverges from iOS. This complements narrower macOS skills already in this profile: macos-ci-recipes (CI-only) and release-macos-spm-packaging (SwiftPM scaffolding/build/packaging, no Xcode project). For visual/HIG conventions ("does this look like a real Mac app"), see the third-party mac-assed-mac-app-skill — that skill covers appearance, this one covers the platform APIs underneath it.

Note the name collision with FlowDeck's own "macOS development" guide (resources/macos-development.md in the flowdeck skill): that one is about driving a running macOS app (clicks, keystrokes, accessibility automation — see flowdeck ui mac), not the platform APIs a macOS app is built from. Same name, different subject — for build/run/UI-automation tasks use flowdeck directly rather than this skill.

Agent behavior contract

  1. Identify which of macOS's three structural differences from iOS is in play before proposing a fix: multi-window (state is per-scene, not global), focus-driven (the menu bar routes through the focused window, not a singleton), keyboard-first (every action needs a menu-bar path, not just a toolbar button). Most "this doesn't feel like a real Mac app" bugs trace back to one of these three.
  2. Before recommending file access code, confirm whether the app is sandboxed (App Store) or Developer-ID direct-distributed — sandbox entitlements and security-scoped bookmarks only apply to the former, but debug builds don't sandbox by default either way, so "works in Xcode" proves nothing.
  3. When bridging AppKit and SwiftUI, determine the host/guest direction first (which framework owns the view hierarchy) — the bridging type differs by direction, not just by "which framework's API do I need."
  4. For distribution questions, first determine whether the project has an .xcodeproj/.xcworkspace or is pure SwiftPM — release-macos-spm-packaging already owns the SwiftPM scaffold/build/package/notarize pipeline end to end; only add net-new distribution guidance here (see references/direct-distribution.md) rather than duplicating it.
  5. Prefer this skill's references/ over recalling WWDC session content from memory — API availability and gotchas below are the source of truth.

Read the full file on GitHub · 86 lines

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. 3d ago First seen · 86 lines · 154 tokens per session scan A f5d1f34f60b5

Subscribe to this mod's changes

macos-development is a skill published in the GitHub repository patrickserrano/lacquer (3 stars, last pushed yesterday), licensed MIT. It adds 154 tokens to every session and 1,548 once invoked, about $0.0008 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.

Related

Other skills, from other repositories

expo-config-plugin

Writing Expo config plugins, withInfoPlist, withAndroidManifest, withDangerousMod, mod compose, plugin testing, and registration in app.config.ts. Triggers on config plugin, with-plugin, withInfoPlist, withAndroidManifest, withDangerousMod, withEntitlementsPlist, withGradleProperties, mod, native config, expo plugin…

fatihkan/badi · 85 tokens

expo-router

File-based routing with Expo Router, dynamic routes, layout hierarchy, deep linking, and navigation patterns. Triggers on expo-router, file-based routing, app dizini, layout.tsx, [id].tsx, deep linking, expo-linking, tab navigation, stack navigation, drawer, prefetch, parallel routes, redirects, navigation, useRouter…

fatihkan/badi · 80 tokens

miniapp-center-hub-refactor

Refactor a growing WeChat Mini Program whose top-level navigation has become scattered across tabs such as home, profile, inbox, integrations, or settings into a clearer hub or center structure. Use when Codex needs to regroup top-level tabs, separate high-frequency action flows from low-frequency settings, define…

Sun-sunshine06/miniprogram-skills · 83 tokens

miniapp-official-scaffold-alignment

Validate or design a WeChat Mini Program scaffold, repository layout, or TypeScript setup against official platform rules. Use when Codex needs to review project.config.json, app.json, miniprogramRoot, page or component file sets, or the initial repo skeleton before feature work begins.

Sun-sunshine06/miniprogram-skills · 69 tokens

design-system

Frontend design conventions for {{ projectname }} -- layout hierarchy, spacing, typography, anti-slop rules. Auto-activates when creating or modifying templates, CSS, or frontend components.

xsovad06/sova · 40 tokens

expo-prebuild

Managed-to-bare transition with Expo prebuild, the ios/android directories, .easignore, native-upgrade discipline, and custom-mod application order. Triggers on expo prebuild, prebuild, managed to bare, bare workflow, native upgrade, ios android directory, easignore, prebuild cache, eject, sync native, native code…

fatihkan/badi · 75 tokens