@nicknisi/pi-auto-theme

Syncs pi's UI theme with the macOS system appearance. Polls dark/light mode every 3 seconds via AppleScript and swaps the active theme to the paired dark/light counterpart. Exists so pi doesn't stay on a dark theme (or vice versa) when the OS switches modes on a schedule.

What it adds

• No slash commands, tools, keybindings, or widgets.
• Hooks two events:
  • session_start — checks OS appearance once, corrects the theme if mismatched, then starts the poll interval.
  • session_shutdown — clears the poll interval.

Theme pairs

Every theme in the map is bidirectional — if the active theme has an entry in PAIRS, it is swapped to its counterpart when the OS mode changes.

Dark	Light
nightowl	lightowl
tokyonight-night	tokyonight-day
catppuccin-mocha	catppuccin-latte
dark	light

If the active theme is not in the map, the extension does nothing (appearance is still polled, but no switch occurs).

Usage

Install and forget. There is nothing to invoke or configure.

On session_start:

1. isDarkMode() runs osascript -e 'tell application "System Events" to tell appearance preferences to return dark mode' with a 2000 ms timeout.
2. If the current theme's mode disagrees with the OS, ctx.ui.setTheme(PAIRS[current]) corrects it.
3. A setInterval(…, 3000) re-polls; on a mode change it swaps the theme to its pair.

Configuration

None. No config files, no options, no environment variables. The theme pairs and 3-second poll interval are hardcoded in index.ts.

Dependencies

• @earendil-works/pi-coding-agent (peer, *) — ExtensionAPI type, pi.on events, ctx.ui.theme.name, ctx.ui.setTheme.
• node:child_process.execSync — shells out to osascript.
• No npm runtime dependencies, no workspace deps.

Caveats

• macOS only. The appearance check is an AppleScript call to System Events. On any other platform execSync throws, the catch returns true (dark), and the extension forces dark themes forever. Behavior on Linux/Windows is "always dark".
• Failure defaults to dark. If osascript errors or times out (>2 s), isDarkMode() returns true, so transient failures read as dark mode.
• Fixed poll interval. 3 seconds; there is up to a 3-second lag between an OS appearance change and the theme swap. No event-driven notification is used.
• pi internals. Depends on ctx.ui.theme.name and ctx.ui.setTheme() from pi's extension API — both could change across pi versions. Theme names must match pi's theme registry exactly (nightowl, tokyonight-night, catppuccin-mocha, etc.); a renamed or removed theme silently no-ops.
• Unknown themes are untouched. If you run a custom theme not in PAIRS, this extension never switches it.
• Synchronous subprocess on the main thread. execSync blocks the extension's poll tick while AppleScript runs; with the 2 s timeout this is bounded but not async.

Install

pi install /Users/nicknisi/Developer/pi-extensions/packages/auto-theme