pi-topping-statusline

OMP's powerline statusline, ported as a Pi extension with modifications.

The bar renders into the editor's top border: π > model · thinking level > path > git > PR (with the default powerline-thin separator), with the session name (hue hashed from the name) right-aligned over a border-colored fill. The box's bottom border carries configurable left/right segment groups — by default a scroll hint on the left, and pi's footer stats plus a context usage graph on the right.

Install

pi install npm:@underactive/pi-topping-statusline

Then /reload (or restart pi). Requirements: a Nerd Font and a truecolor terminal for the default look — the Symbols setting in /topping-statusline-settings (unicode or ascii) drops the font requirement.

Configuration — /topping-statusline-settings

/topping-statusline-settings opens a settings TUI with a live preview of the box's top and bottom bars. Requires TUI mode. Settings persist to ~/.pi/agent/pi-topping-statusline/settings.json and apply live.

╔═[ Pi Topping Statusline: Settings ]════════════════════════════╗
╟─ Preview ──────────────────────────────────────────────────────╢
║                                                                ║
║ ╭── π > ⬢ Sonnet · ◉ max > pi/pi-topping > main ── session ──╮ ║
║ │                                                            │ ║
║ ╰── ↑ 3 more ── ↑ 12.4K ↓ 3.1K R 148K W 12K 92.3% $0.42 42%──╯ ║
║                                                                ║
╟─ Global ───────────────────────────────────────────────────────╢
║  ▸ [■] Transparent Segments                                ON  ║
║    Separator                               ‹ powerline-thin ›  ║
║    Symbols                                       ‹ nerdfont ›  ║
║    Border style                                   ‹ rounded ›  ║
║    [■] Rainbow border on max thinking                      ON  ║
║    [■] Animate rainbow border                              ON  ║
║    [ ] Embed 'Working' indicator                           OFF ║
║                                                                ║
╟─ Top Left Segment Group ───────────────────────────────────────╢
║    [■] Pi symbol                                           ON  ║
║    [■] Model                                               ON  ║
║    [ ] Provider                                            OFF ║
║    [■] Thinking level                                      ON  ║
║    [■] Path                                                ON  ║
║    [■] Git                                                 ON  ║
║    [■] PR                                                  ON  ║
║                                                                ║
╟─ Top Right Segment Group ──────────────────────────────────────╢
║    [ ] Token rate                                          OFF ║
║    [■] Session name                                        ON  ║
║  … Bottom Right / Bottom Left groups — 8 more toggles          ║
║                                                                ║
╟─ Feeds ────────────────────────────────────────────────────────╢
║    1. type         pi-prompt-cache/savings                     ║
║    1. field        savedUsd                                    ║
║    1. prefix       CS                                          ║
║    1. format                                     ‹ currency ›  ║
║    1. remove this feed                                         ║
║    + add feed                                                  ║
║                                                                ║
║  ↑↓ move  ←→ cycle  ␣ toggle  ⏎ apply/edit  esc cancel         ║
╚════════════════════════════════════════════════════════[ 1/30 ]╝

Section	Settings
Global	Transparent Segments · Separator (powerline powerline-thin slash pipe ascii) · Symbols (nerdfont unicode ascii — stored in settings.json as nerd/unicode/ascii) · Border style (rounded heavy double single) · Rainbow border on max thinking · Animate rainbow border · Embed 'Working' indicator
Top Left Segment Group	Pi symbol · Model · Provider · Thinking level · Path · Git · PR
Top Right Segment Group	Token rate · Session name
Bottom Right Segment Group	Feeds · Token rate · Pi stats · Context bar · Context stats
Bottom Left Segment Group	Scroll hint · Feeds · Token rate
Feeds	One subscription per row: type · field · prefix · format, plus add/remove
Defaults	Transparent on · Separator powerline-thin · Symbols nerdfont · Border style rounded · Rainbow border on · Animate rainbow border on · Embed 'Working' indicator off

With Rainbow border on max thinking on (the default), cycling the thinking level to max replaces the border's fixed theme color with a rainbow: a full hue cycle distributed around the box perimeter. Animate rainbow border is also on by default, so the hues flow around the border (~14s per rotation), like Apple Intelligence's screen border. Turn animation off to keep the rainbow at a fixed color phase without its repaint timer; the settings preview uses a stable phase too. Any other thinking level keeps the normal theme border color. Disable animation over slow SSH links or in terminals with expensive redraws while retaining the rainbow border.

Embed 'Working' indicator (off by default) moves pi's streaming status — spinner, message, and any loader text a topping such as pi-topping supplies — out of its own row and into the top-left group, right after the Pi symbol and its chevron. The remaining left segments (model, path, git, PR) step aside while a response streams and return when it ends; the Pi symbol never moves. The status appears instantly when a stream starts; when it ends, the swap back cross-fades over 750ms (the status sinks into the bar background, then the user's segments rise out of it) rather than cutting. A status too long for the bar is truncated without an ellipsis, as pi's own border does. Requires pi 0.85 or later. Toggling the setting reinstalls the editor through pi, so it applies immediately, even mid-response. Only the statusline's own editor opts in: when another extension owns the editor slot and is wrapped, pi keeps its standalone working row.

Segments

Ported with pi data: pi, model (model · provider · thinking level), path (worktree/scratch-dir aware; always strips ~/Projects and /work prefixes — not exposed in the settings TUI), git (branch + *unstaged +staged ?untracked, HEAD fs-watch), pr (via gh, hidden if missing), session_name, token_rate (live tok/s — accent while active, held 1.5s, faded 0.5s, then a dim --- tok/s placeholder; estimate pipelined from pi-topping's word-count EMA; available in the top-right, bottom-left, and bottom-right groups), pi_stats, context_graph (bar + stats), scroll_hint, plus feeds (documented below).

When the terminal narrows: right segments drop first, then the path shrinks (to ~8 cells), then left segments drop end-first — the path is always the last to go.

Feeds

feeds surfaces values other extensions publish as custom session entries, so the bar can carry figures this extension knows nothing about. There is one subscription list, shared by the Bottom Right and Bottom Left Feeds toggles — enabling both shows the same values twice. Each subscription is four fields, all configurable in the settings TUI:

Field	Meaning	Example
type	the publisher's customType	pi-prompt-cache/savings
field	property of the entry's data to read	savedUsd
prefix	literal label drawn before the value	CS
format	currency, number, or text	currency

In settings.json the first column is persisted as customType; the settings TUI labels it type. That example renders CS$1.44. The prefix is glued directly to the value, so write it as TOK when you want TOK 42; leading and trailing spaces survive, while escape sequences and control characters are stripped.

The list ships seeded with the savings feed published by pi-prompt-cache, which is where the currency rules come from: figures under half a cent are hidden, matching that extension's own footer cutoff so the two never disagree. That floor hides the negative values published early in a session, before the cache-write premium is amortized by reads. Above the floor, currency shows two decimals below $100 and whole dollars above.

A feed contributes nothing when its publisher is absent, has published nothing this run, or reports a value its format suppresses; the segment disappears entirely once every feed is quiet, so it costs nothing to leave switched on. Feed values are shown in dim text; a value that remains unchanged for five minutes fades into the statusline background over 500ms and then hides. It reappears in dim text only when that configured field's value changes. Publishers typically reset per process run, so entries predating the current session start (--resume, /reload, /new, fork) are ignored rather than shown as a stale total. During steady-state rendering, the session is re-read at most once every two seconds, because pi copies the whole entry list on each read while the bar re-renders on every keystroke; changing subscriptions or starting a new session forces an immediate scan.

Publishing a feed

Any extension can expose a value to this bar with one call and no dependency on this package — the contract is a pi custom session entry, not an API of ours:

import type { ExtensionAPI } from "@earendil-works/pi-coding-agent";

export default function (pi: ExtensionAPI) {
	let published = 0;
	pi.on("turn_end", () => {
		const savedUsd = currentSavings();
		// Publish only when the figure actually moves: consumers read the newest
		// entry, never the history.
		if (Math.abs(savedUsd - published) < 0.01) return;
		published = savedUsd;
		pi.appendEntry("my-extension/savings", { savedUsd });
	});
}

A user then subscribes with type my-extension/savings, field savedUsd, and whatever prefix and format they like.

Use appendEntry. It writes a type: "custom" entry, which is what the bar looks for. It checks the entry kind before the customType, because custom message entries carry a customType field too — so a value pushed through sendMessage is never read.

Make data an object. The subscription names a field, and the bar reads data[field]. A bare number or string published as the whole payload cannot be addressed. Several fields in one entry are fine; each can be subscribed to separately, and one entry can feed several segments.

Match the value to the format. currency and number need a finite number and ignore anything else, so a pre-formatted "$1.44" string only works under text. Publish the raw number and let the user pick the presentation.

Publish at turn boundaries, not per token. A high emission rate buys no extra freshness, and every append writes to the session file.

Re-publish after a session start if your figure carries over. As noted above, entries written before the consumer's session_start are ignored, so after --resume the segment stays empty until you publish again. Per-run counters get this for free; a lifetime counter should emit once on the first turn of each run to become visible again.

Nothing appears in the transcript. Custom entries are excluded from LLM context, and pi renders nothing for a customType with no registered entry renderer — a feed costs a line in the session file and no screen space.

Name the type after your extension (your-extension/metric) to avoid collisions, and document the field names and units — those are the strings your users type into the settings TUI.

Caveats

• Other editor-replacing extensions are wrapped rather than raced — their editor renders inside this box — but ones that draw their own bar or chrome will clash visually.
• The palette is OMP's dark theme; light terminal themes will look off.

Development

Requires Node >= 22.19 (the test runner uses --import with TypeScript resolution).

ln -s "$(pwd)" ~/.pi/agent/extensions/pi-topping-statusline
npm install && npm run typecheck && npm test

Attribution

The statusline design and most of the rendering code come from oh-my-pi (MIT, © 2025 Mario Zechner, © 2025–2026 Can Bölük), itself a fork of Mario Zechner's pi. This port is MIT as well.