mac:jxa SKILL.md skillA
mac:jxa from bendrucker/claude is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add bendrucker/claude/mac:jxa@git:20261018.8bb1907Pins git:20261018.8bb1907 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- bendrucker/claude
- Path
plugins/mac/skills/jxa/SKILL.md- Versions recorded
- 4
- Latest version
- git:20261018.8bb1907, committed Oct 18, 2026
- First version recorded
- Apr 2, 2026
- Size
- 1,584 bytes
- Repository stars
- 18
- License
- MIT
Reference for writing JXA (JavaScript for Automation) scripts run through `osascript -l JavaScript`. Covers the JavaScriptCore ES5 constraints, `run(argv)`, and the `Application()` bridge.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# JXA
JavaScript for Automation (JXA) automates macOS apps via the `Application()` bridge. It runs on JavaScriptCore (ES5).
## Language Constraints
- Use `var` (not `let`/`const`)
- Use for-loops (JXA arrays lack `.map()`, `.filter()`, `.forEach()`)
- Return a JSON string from `run()` (not an object)
```javascript
// WRONG: JXA arrays don't have .map()
// var names = app.windows().map(function(w) { return w.name(); });
// CORRECT: use a for-loop
var windows = app.windows();
var names = [];
for (var i = 0; i < windows.length; i++) {
names.push(windows[i].name());
}
```
## Script Files
Script files define a `function run(argv)` entry point. `osascript` calls it and prints the return value. The function must be named `run`, not `_run`.
```javascript
#!/usr/bin/env osascript -l JavaScript
function run(argv) {
var finder = Application("Finder");
var items = finder.desktop.items();
var names = [];
for (var i = 0; i < items.length; i++) {
names.push(items[i].name());
}
return JSON.stringify(names);
}
```
## Tips
- Use `properties()` for batch reads instead of individual getters
- Use `.whose()` for filtering when the app supports it (pushes work to the app)
…Read the whole file at its exact version.
How to install
mdr add bendrucker/claude/mac:jxa@sha256:60e8e35c0c520c03The line at the top of this page pins the label git:20261018.8bb1907, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_fufvnlyn6huh4yu2)
5 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 4 versions of this file, between Apr 2, 2026 and Oct 18, 2026, about one every 67 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261018.8bb1907 latest | 2026-10-18 | 8bb1907 | 1,584 B | A | view · diff |
| git:20260902.42e53f9 | 2026-09-02 | 42e53f9 | 1,553 B | A | view · diff |
| git:20260615.1ec44ee | 2026-06-15 | 1ec44ee | 1,553 B | A | view · diff |
| git:20260402.951fb7c | 2026-04-02 | 951fb7c | 1,567 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (1584 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
bendrucker/claude · 18 stars · license MIT · pushed 2026-11-07 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_fufvnlyn6huh4yu2 GET https://markdownregistry.com/api/v1/resolve?ref=bendrucker/claude/mac:jxa GET https://markdownregistry.com/api/v1/blob/60e8e35c0c520c03ae19f8a733a9ea84c22c5972c428a308624a9103c15ff712
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.