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peekaboo

macOS screen capture, accessibility inspection, and background-first app/window/UI automation with Peekaboo v4.

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Peekaboo

Use Peekaboo for native macOS capture, UI inspection, and automation. Prefer its native app, window, Accessibility, and input commands over AppleScript or osascript whenever Peekaboo exposes the operation.

Binary

  • Prefer ~/bin/peekaboo when present; it is Peter's signed local release copy.
  • Otherwise use peekaboo from PATH.
  • Check the selected binary before relying on syntax or installed state.
PB="${PEEKABOO_BIN:-$HOME/bin/peekaboo}"
[ -x "$PB" ] || PB="$(command -v peekaboo)"
"$PB" --version

Runtime host and permissions

  • Launch Peekaboo.app without taking focus when a GUI Bridge host is needed: open -gj -a Peekaboo.
  • The app owns its TCC grants and serves ~/Library/Application Support/Peekaboo/bridge.sock. The reusable daemon has separate permissions and serves daemon.sock; daemon start is not an app launch.
  • Normal runtime selection prefers a healthy reusable daemon, then the GUI host, before starting a daemon. Use bridge status --verbose --json to see the actual selection. When app-held TCC is required, pass --bridge-socket "$HOME/Library/Application Support/Peekaboo/bridge.sock" and verify hostKind: gui instead of assuming the app was selected.
  • Check permissions status --all-sources --json. Grant Screen Recording, Accessibility, and Event Synthesizing to the process reported as the selected source, not merely to the invoking terminal.
  • Prefer Bridge capture from SSH, LaunchAgent, Codex, and other background sessions. --no-remote --capture-engine cg is a local-debug override and can return wallpaper-only pixels outside the active Aqua session.
  • Never run an unsigned or ad-hoc build against saved TCC or Keychain state.

Background-first safety

  • Keep the user's foreground app, keyboard focus, and physical cursor untouched by default. Supply an exact --app, --pid, --window-id, or fresh snapshot target and use Peekaboo's background delivery.
  • Never add --foreground merely to make a command work speculatively. Add it only when the user authorized foreground interaction or the target demonstrably rejects background delivery.
  • Shared-cursor and targetless global input must use explicit foreground mode. This includes move, drag, targetless/smooth scroll, and targetless keyboard input; click --long-press is foreground-only. Foreground mode can interrupt the user.
  • Background typing, key chords, and paste need a resolvable app/PID and Event Synthesizing permission. Window selectors require foreground mode for these process-targeted keyboard operations.
  • Do not click, type, paste, quit, or otherwise mutate UI unless the user asked or the target is a controlled test. Re-observe after mutations; never replay an indeterminate input blindly.

v4 command names

  • Inventory: app list, window list, and screen list; there is no top-level list command.
  • Screenshots and UI inspection: see --no-elements for pixels, or see --tree --no-screenshot for AX-only text; do not use the removed image or inspect-ui CLI commands.
  • Keyboard chords: press; do not use the removed hotkey command.
  • Named Accessibility actions: action; do not use perform-action.
  • Coordinate clicks: click --at x,y; do not use --coords.

Common commands

"$PB" permissions status --all-sources --json
open -gj -a Peekaboo
"$PB" bridge status --verbose --json

"$PB" screen list --json
"$PB" app list --include-hidden --include-background --json
"$PB" window list --app Safari --json

# Screenshot only; observation does not activate the target app.
"$PB" see --no-elements --mode screen --path /tmp/screen.png --json

# Interactive map plus a directly accessible image artifact.
"$PB" see --app Safari --annotate --path /tmp/safari-see.png --json

# AX-only inspection, with no pixel capture or screenshot artifact.
"$PB" see --app Safari --tree --no-screenshot --json

# Use IDs and the snapshot returned by a fresh `see`.
"$PB" click --on "$ELEMENT_ID" --snapshot "$SNAPSHOT_ID" --json
"$PB" action AXPress --on "$ELEMENT_ID" --snapshot "$SNAPSHOT_ID" --json

# Process-targeted background keyboard delivery.
"$PB" type "text" --app TextEdit --json
"$PB" press cmd+shift+t --app Safari --json
"$PB" paste "text" --app TextEdit --json

"$PB" tools --json
"$PB" tools describe click --json

Click coordinates safely

Screenshot pixels are not automatically click coordinates. click --at uses logical points. With target flags, coordinates are relative to the resolved window; without them they are global screen coordinates. Add --global to make targeted coordinates use the global logical space. Use screen list --json for display bounds and scale factors when converting Retina pixels.

A background coordinate click requires an explicit snapshot from a fresh exact-window observation. First resolve the canonical window ID, then observe that exact window and use both its window ID and returned snapshot ID:

"$PB" window list --app Safari --json
"$PB" see --app Safari --window-id 12345 --path /tmp/safari.png --json
"$PB" click --window-id 12345 --at 20,40 --snapshot "$SNAPSHOT_ID" --json

Peekaboo revalidates the captured PID, process generation, window ID, and bounds before dispatch. If the exact receipt cannot be established, background input must fail instead of guessing. Use --foreground only when visible shared-pointer interaction is intentional. Background right/double click can be dispatched to an exact route but remains effect-unverifiable; run a fresh see before retrying.

For element work, prefer IDs from a fresh see and pass the snapshot explicitly. Queries and the implicit latest snapshot are convenient but less deterministic. After an action changes UI, capture a new snapshot rather than reusing stale IDs.

Workflow

  1. Resolve PB, confirm its version, and launch the signed GUI host in the background when app-held TCC is needed.
  2. Verify the selected Bridge host and compare permissions across sources.
  3. Resolve the target with app list or window list; prefer PID/window ID over a broad name or title when cleanup or mutation must be exact.
  4. Observe without focus theft: use see --no-elements for a screenshot, ordinary see for element IDs, or see --tree --no-screenshot for AX-only inspection. Pass --path when the caller needs the image file.
  5. Interact in the background with an exact target and fresh snapshot. Prefer action or an element click over coordinate input.
  6. Verify every mutation with a new see or a purpose-built read-only command.
  7. Escalate to explicit --foreground only for authorized shared cursor/global input or a confirmed application limitation; never silently promote modes.
  8. Use capture live for change-aware capture, capture video for video frame sampling, tools describe <name> for MCP schemas, and <command> --help for current CLI syntax.
  9. Verify image artifacts with sips -g pixelWidth -g pixelHeight <path> or view them locally.

Source of truth: ~/Projects/peekaboo/docs/commands/ and the selected binary's --help output.

Repository
steipete/agent-scripts
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