robinebers/openusage is a native macOS menu-bar application that tracks usage of AI coding subscriptions, including limits, credits, and spending. Developers use it to monitor plans from services such as Claude, Codex, Cursor, and Copilot, while the catalogue entries support related workflows.
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.
npx agentmods add skills/robinebers/openusage/macos-appkit-interopnpx skills add robinebers/openusage --skill macos-appkit-interopgit clone --depth 1 https://github.com/robinebers/openusageWrote 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.
[](https://agentmods.dev/skills/robinebers/openusage/macos-appkit-interop)<a href="https://agentmods.dev/skills/robinebers/openusage/macos-appkit-interop"><img src="https://agentmods.dev/badge/skills/robinebers/openusage/macos-appkit-interop.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00038 | $0.00608 |
| Opus 5 | $0.00019 | $0.00304 |
| Sonnet 5 | $0.00008 | $0.00122 |
| Haiku 4.5 | $0.00004 | $0.00061 |
Grade A, and why
macos-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 5d 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.
This is a copy
84% identical to appkit-interop — 6 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.
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
NSViewRepresentablewhen you need a specific AppKit view with lightweight lifecycle needs. - Use
NSViewControllerRepresentablewhen 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.
What ships with it
4 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.
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.
- 5d ago First seen · 69 lines · 38 tokens per session scan A 64b0797be756
macos-appkit-interop is a skill published in the GitHub repository robinebers/openusage (3,975 stars, last pushed 2d ago), licensed MIT. It adds 38 tokens to every session and 608 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 84% identical to appkit-interop, differing in 6 lines, and is treated as a copy.
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