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  ║
║    [■] NVIDIA-green when using Switchyard                  ON  ║
║    [■] Animate Switchyard green border                     ON  ║
║    [ ] Embed status spinners                               OFF ║
║    [■] Embed compaction progress                           ON  ║
║                                                                ║
╟─ 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         ║
╚════════════════════════════════════════════════════════[ 1/33 ]╝

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.

When the active model provider is switchyard and NVIDIA-green when using Switchyard is on (the default), the border uses an NVIDIA-green gradient from #84c51a to #0b3d20. Animate Switchyard green border is also on by default, so it sweeps around the box on the same ~14s cycle as the max-thinking rainbow, independently of Animate rainbow border. Turn the animation setting off to keep the green gradient at a fixed color phase without its repaint timer. When enabled, green takes precedence over the max-thinking rainbow and ignores thinking level; turn the NVIDIA-green setting off to restore the normal theme or rainbow border.

Embed status spinners (off by default) moves pi's status indicators out of their own row and into the top-left group, right after the Pi symbol and its chevron. On pi 0.86 and later this covers the working, retry, compaction, and branch-summary spinners; pi 0.85 embeds only the working indicator. The configured model, provider, and thinking details remain visible after the status; path, git, and PR step aside while a status is visible, and the Pi symbol never moves. An appearing status slides out from behind the Pi symbol's chevron over 300ms, pushing the model details right; one that replaces a status still on screen swaps in place without sliding. A cleared status is held briefly so handoffs between spinners do not flash the left segments. Only the working status cross-fades over 750ms; stable model details remain solid, and the message-style spinners cut after the hold. While the bar hosts the working status, it announces that on pi's extension event bus, and pi-topping's loader slides its response model out the same way; anywhere else that model appears at once.

A status too long for the bar is truncated. The working spinner keeps pi's bare cut, while the message-style spinners use an ellipsis. Focusing the embed row in the settings preview shows the longest compaction sample. 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 status row.

Embed compaction progress (on by default) hosts pi-topping-compact's compaction progress in the box's bottom border while a compaction runs. Its phosphor bar stands in for the context graph, followed by the tokens being compacted over the window and as a share of it (86K/131K (66%)), and 57% summarized · 16.3s — how much has been summarized so far, and the time taken — stands in for pi's stats. The bar and its label follow the Context bar and Context stats toggles. The moment the compaction ends, pi's stats and the context graph return, the graph sizing the compacted context as an estimate until the next response (see Segments), and pi-topping-compact shows its completion result above the editor as it always has. Nothing changes without pi-topping-compact installed: the two talk over pi's extension event bus, this bar announcing whether it hosts the progress and pi-topping-compact broadcasting it only while it does, otherwise keeping its own above-editor widget. With the setting off, with Pi stats, Context bar, and Context stats all off, or with the terminal too narrow for the stand-ins, that widget is used instead. Focusing the setting's row in the settings preview shows the bottom bar mid-compaction.

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), with compaction_info and compaction_graph standing in for pi_stats and context_graph while pi-topping-compact's progress is hosted. On pi 0.86 and later, pi_stats includes cache-warming refreshes folded into pi's own footer totals, so cache R/W and cost can increase while idle; this segment matches the host footer by construction.

Between a compaction and the next response, pi reports context usage as unknown. Rather than vanish for that stretch, context_graph shows pi's own estimate of the compacted context, the summary plus the kept messages sized by pi's estimator, marked with ~ (~9.2%/131K). It is the same figure pi-topping-compact reports in its result. pi's measured figure replaces it after the next response.

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:

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.