Imported from reason-machines/trending-skills (skills/pi-computer-use/SKILL.md). Install upstream with npx skills add reason-machines/trending-skills --skill pi-computer-use. Copyright stays with the author.

pi-computer-use

Skill by ara.so — Daily 2026 Skills collection.

pi-computer-use gives Pi agents a semantic computer-use surface for visible macOS windows. It prefers Accessibility (AX) targets (like @e1) over raw coordinates, returns semantic state after every action, and attaches screenshots only when AX coverage is too weak.

Installation

Via Pi (recommended)

pi install git:github.com/injaneity/pi-computer-use#v0.2.1

Pin to a specific version:

pi install -l git:github.com/injaneity/pi-computer-use#v0.2.1

Via npm

npm install @injaneity/pi-computer-use
# or pin a version
npm install @injaneity/pi-computer-use@0.2.1

Remove

pi remove git:github.com/injaneity/pi-computer-use#v0.2.1
npm remove @injaneity/pi-computer-use

First-Run Permissions

On first session, macOS will prompt for permissions for:

~/.pi/agent/helpers/pi-computer-use/bridge

Grant both:

• Accessibility — required for AX ref targeting
• Screen Recording — required for screenshots

How It Works

Three components:

1. Pi extension (extensions/computer-use.ts) — registers public tools and /computer-use command
2. TypeScript bridge (src/bridge.ts) — manages window state, AX refs, fallback policy, batching, execution metadata
3. Native Swift helper (native/macos/bridge.swift) — talks to macOS Accessibility, ScreenCaptureKit, AppKit, CoreGraphics

Available Tools

Core Workflow

Always start a session with screenshot to select the controlled window and obtain AX refs:

// 1. Discover apps and windows if target is ambiguous
list_apps()
list_windows({ app: "Safari" })

// 2. Select the window and get AX state
screenshot({ window: "@w1" })

// 3. Act on AX refs returned from screenshot
click({ window: "@w1", ref: "@e1" })
set_text({ ref: "@e2", text: "https://example.com" })
keypress({ keys: ["Enter"] })

AX Ref Targeting (Preferred)

AX refs like @e1, @e2 are returned by screenshot and carry capability metadata:

• canSetValue — supports set_text
• canPress — supports click
• canFocus — can receive focus
• canScroll — supports scroll
• adjust — supports value adjustment

// Click by AX ref — no coordinates needed
click({ ref: "@e1" })

// Scroll a specific element
scroll({ ref: "@e3", scrollY: 600 })

// Replace text field value atomically
set_text({ ref: "@e2", text: "hello world" })

Coordinate Fallback

Use coordinates only when no suitable AX target exists. Always include stateId from the latest screenshot to guard against stale state:

click({ x: 320, y: 180, stateId: "abc123" })

Batching Actions

Use computer_actions to batch obvious sequential steps. One semantic state update is returned after all actions:

computer_actions({
  stateId: "abc123",
  actions: [
    { type: "click", ref: "@e1" },
    { type: "set_text", ref: "@e2", text: "https://example.com" },
    { type: "keypress", keys: ["Enter"] }
  ]
})

Each action in the result includes execution metadata:

• stealth — background-safe AX path (no focus takeover)
• default — required focus or raw event fallback

Window Management

// List windows for a specific app
list_windows({ app: "Finder" })

// Target a specific window in all subsequent calls
screenshot({ window: "@w2" })

// Arrange window by preset
arrange_window({ window: "@w1", preset: "left-half" })

// Arrange window with explicit frame
arrange_window({ window: "@w1", frame: { x: 0, y: 0, width: 1280, height: 800 } })

Screenshot Modes

Control when screenshots are attached with the image option:

screenshot({ window: "@w1", image: "auto" })   // default: attach when AX coverage is weak
screenshot({ window: "@w1", image: "always" }) // always attach
screenshot({ window: "@w1", image: "never" })  // never attach, AX state only

Common Patterns

Open URL in Safari

list_windows({ app: "Safari" })
screenshot({ window: "@w1" })
// @e1 = address bar (from AX state)
set_text({ ref: "@e1", text: "https://example.com" })
keypress({ keys: ["Enter"] })

Fill a Form

screenshot({ window: "@w1" })
// Use refs from AX state
set_text({ ref: "@e3", text: "Jane Doe" })
set_text({ ref: "@e4", text: "jane@example.com" })
click({ ref: "@e5" }) // Submit button

Keyboard Shortcut

keypress({ keys: ["Cmd", "T"] })       // New tab
keypress({ keys: ["Cmd", "Shift", "N"] }) // New incognito window
keypress({ keys: ["Escape"] })

Scroll a Page

scroll({ ref: "@e2", scrollY: 800 })   // Scroll element down
scroll({ ref: "@e2", scrollY: -400 })  // Scroll up

Drag and Drop

drag({ fromX: 100, fromY: 200, toX: 400, toY: 200 })

Strict AX Mode (Stealth / Background-Safe)

Enable strict AX mode to prevent focus changes, raw pointer events, raw keyboard events, and cursor takeover. All actions must succeed via background-safe AX paths:

// Via config (see Configuration section)
// Actions will report `stealth` in execution metadata when successful

Strict mode errors will surface if an action requires foreground focus and strict mode is active.

Configuration

Inspect effective config in Pi:

/computer-use

Config can be set via config files or environment variable overrides. Key options:

See docs/configuration.md for full config file format and environment variable overrides.

Development

# Install dependencies
npm install

# Run checks
npm test

# Run local checkout without loading installed copy
pi --no-extensions -e .

Benchmarks

# Default QA benchmark
npm run benchmark:qa

# Full benchmark (may open apps)
npm run benchmark:qa:full

See benchmarks/README.md for metrics, regression policy, and comparison workflow.

Troubleshooting

Permissions not granted

Re-run and grant both Accessibility and Screen Recording to:

~/.pi/agent/helpers/pi-computer-use/bridge

On macOS, go to System Settings → Privacy & Security → Accessibility and Screen Recording.

AX refs are stale

Take a fresh screenshot to get updated stateId and new refs before acting. Stale-action detection uses stateId to reject outdated coordinates or refs.

Browser window not targeted correctly

Use list_windows({ app: "Safari" }) (or Chrome/Firefox) first, then explicitly pass window: "@wN" to screenshot and subsequent actions.

Strict AX mode errors

An action failed to complete via background-safe AX path. Either disable strict mode or identify an AX ref with canPress/canSetValue that supports the background path.

Helper not found

Ensure Pi installed the native helper:

ls ~/.pi/agent/helpers/pi-computer-use/bridge

If missing, reinstall: pi install git:github.com/injaneity/pi-computer-use#v0.2.1

Key Concepts

• AX refs (@e1, @e2, …) — semantic element handles from macOS Accessibility API, stable within a state
• Window refs (@w1, @w2, …) — stable handles from list_windows
• stateId — opaque ID from the latest screenshot; attach to coordinate-based actions to detect stale state
• stealth execution — action completed via AX without foregrounding the app or moving the real cursor
• semantic state — structured AX tree returned after every action, used instead of screenshots when coverage is sufficient

References

• Usage guide
• Configuration
• Troubleshooting
• Benchmarks
• Pi