What is appkit-interop?

Guidance for connecting macOS SwiftUI interfaces to AppKit, the older native macOS UI framework, when SwiftUI lacks a needed capability. It covers views, controllers, windows, menus, panels, and responder-chain behavior.

Use it to wrap AppKit controls, coordinate controller lifecycles, access windows or panels, manage menus, handle drag and drop, show file dialogs, or control first-responder focus.

It helps add native macOS behavior while keeping SwiftUI responsible for ordinary app state and layout.

appkit-interop — Skill for Codex by fanfan-de/anybox

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 fanfan-de/anybox --skill appkit-interop

Clone the repo

git clone --depth 1 https://github.com/fanfan-de/anybox

Made for: 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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/fanfan-de/anybox/appkit-interop/github.svg)](https://agentmods.dev/skills/fanfan-de/anybox/appkit-interop)

Your own site

<a href="https://agentmods.dev/skills/fanfan-de/anybox/appkit-interop"><img src="https://agentmods.dev/badge/skills/fanfan-de/anybox/appkit-interop/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/fanfan-de/anybox/appkit-interop"><img src="https://agentmods.dev/badge/skills/fanfan-de/anybox/appkit-interop.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 603 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 94% copy Near-identical to another mod 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	$0.00036	$0.00603
Opus 5.5	$0.00014	$0.00241
Sonnet 5.5	$0.00007	$0.00121
Haiku 4.5	$0.00004	$0.00060

Measured 2mo ago against content hash 7c91be82e303, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

appkit-interop 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 2mo 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.

Origin

This is a copy

94% identical to macos-appkit-interop — 4 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/Anybox-Plugins/build-macos-apps/skills/appkit-interop/SKILL.md · 69 lines

How it starts

The opening of the file, as written. The whole thing — 69 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AppKit Interop

Quick Start

Use this skill when SwiftUI is close but not quite enough for native macOS behavior. Keep the bridge as small and explicit as possible. SwiftUI should usually remain the source of truth, while AppKit handles the imperative edge.

Choose The Smallest Bridge

Use pure SwiftUI when the required behavior already exists in scenes, toolbars, commands, inspectors, or standard controls.
Use NSViewRepresentable when you need a specific AppKit view with lightweight lifecycle needs.
Use NSViewControllerRepresentable when you need controller lifecycle, delegation, or presentation coordination.
Use direct AppKit window or app hooks when you need NSWindow, responder-chain, menu validation, panels, or app-level behavior.

Workflow

Name the capability gap precisely.
- Window behavior
- Text system behavior
- Menu validation
- Drag and drop
- File open/save panels
- First responder control
Pick the smallest boundary that solves it.
- Avoid porting a whole screen to AppKit when one wrapped control or coordinator would do.
Keep ownership explicit.
- SwiftUI owns value state, selection, and observable models.
- AppKit objects stay inside the representable, coordinator, or bridge object.
Expose a narrow interface back to SwiftUI.
- Bindings for editable state
- Small callbacks for events
- Focused bridge services only when necessary
Validate lifecycle assumptions.
- SwiftUI may recreate representables.
- Coordinators exist to hold delegate and target-action glue, not as a second app architecture.

References

references/representables.md: choosing between view and view-controller wrappers, plus coordinator patterns.
references/window-panels.md: window access, utility windows, and open/save panels.
references/responder-menus.md: first responder, command routing, and menu validation.
references/drag-drop-pasteboard.md: pasteboard, file URLs, and desktop drag/drop edges.

Read the full file on GitHub · 69 lines

Files

What ships with it

5 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.

2mo ago First seen · 69 lines · 36 tokens per session scan A 7c91be82e303

Subscribe to this mod's changes

appkit-interop is a skill published in the GitHub repository fanfan-de/anybox (55 stars, last pushed 1mo ago), licensed MIT. It adds 36 tokens to every session and 603 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 94% identical to macos-appkit-interop, differing in 4 lines, and is treated as a copy.

appkit-interop next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
appkit-interopfanfan-de/anybox	Skill	55	1mo ago	MIT	A	36	Codex
imagegenopenai/codex	Skill	133k	yesterday	Apache-2.0	A	113	Codex
playwright-climicrosoft/playwright	Skill	99k	yesterday	Apache-2.0	A	19	Claude Code
local-ai-agentsmicrosoft/ai-agents-for-beginners	Skill	79k	4d ago	MIT	A	200	Claude Code, Codex
systematic-debuggingobra/superpowers	Skill	313k	3d ago	MIT	A	21	Claude Code
next-cache-components-adoptionvercel/next.js	Skill	143k	today	MIT	A	95	Claude Code
next-partial-prefetching-adoptionvercel/next.js	Skill	143k	today	MIT	A	103	Claude Code