opentui(v6): header chrome — dense status bar (Variant A)

ui-opentui/src/boundary/schema/SessionInfo.ts

@@ -10,11 +10,15 @@
  * unset — a stray shape never crashes the reducer.
  *
  * Wire field names are verified against `tui_gateway/server.py`:
- *   - session.info  → `_session_info()` (server.py:~1830): top-level `model`,
- *     `reasoning_effort`, `fast`, `cwd`, `branch`, `running`, plus a nested
- *     `usage` (`_get_usage()`, server.py:~1698) carrying `context_used`,
- *     `context_max`, `context_percent`, `compressions` (context_* only present
- *     when the compressor knows a context length).
+ *   - session.info  → `_session_info()` (server.py:~1798): top-level `model`,
+ *     `reasoning_effort`, `fast`, `cwd`, `branch`, `running`, `profile_name`,
+ *     `update_behind` (Optional[int] — null until the prefetched check lands),
+ *     `update_command`, `mcp_servers` (list of {name,transport,connected,tools}
+ *     dicts from `get_mcp_status()`), plus a nested `usage` (`_get_usage()`,
+ *     server.py:~1683) carrying `context_used`, `context_max`,
+ *     `context_percent`, `compressions` (context_* only present when the
+ *     compressor knows a context length) and `cost_usd` (only when the pricing
+ *     estimate succeeds).
  *   - startup.catalog → `@method("startup.catalog")` (server.py:~8521):
  *     `{ tools:{total, toolsets:[{name,count,enabled,tools}]},
  *        skills:{total, categories:[{name,count}]}, mcp:{servers:[]} }`.
@@ -38,7 +42,8 @@ const UsageSchema = Schema.Struct({
   context_used: opt(Num),
   context_max: opt(Num),
   context_percent: opt(Num),
-  compressions: opt(Num)
+  compressions: opt(Num),
+  cost_usd: opt(Num)
 })
 
 export const SessionInfoPatchSchema = Schema.Struct({
@@ -48,6 +53,12 @@ export const SessionInfoPatchSchema = Schema.Struct({
   cwd: opt(Str),
   branch: opt(Str),
   running: opt(Bool),
+  // status-bar chrome extras (Epic 1.3): update banner, profile badge, MCP count.
+  // `update_behind` is null on the wire until the async update check resolves.
+  update_behind: opt(Schema.NullOr(Num)),
+  update_command: opt(Str),
+  profile_name: opt(Str),
+  mcp_servers: opt(Schema.Array(Schema.Unknown)),
   // top-level context fallback (used when there's no nested `usage`)
   context_used: opt(Num),
   context_max: opt(Num),

ui-opentui/src/logic/store.ts

@@ -164,6 +164,21 @@ export interface SessionInfo {
   contextMax?: number
   contextPercent?: number
   compressions?: number
+  /** Estimated session cost in USD (`usage.cost_usd` — only when the gateway's
+   *  pricing estimate succeeds; absent otherwise). */
+  costUsd?: number
+  /** Commits behind the remote (`update_behind`) — null/absent until the async
+   *  update check resolves; >0 drives the transient update notice in the bar. */
+  updateBehind?: number
+  /** The recommended update command (`update_command`), paired with updateBehind. */
+  updateCommand?: string
+  /** Active profile name (`profile_name`); the bar badges it when non-default. */
+  profileName?: string
+  /** Count of configured MCP servers (`mcp_servers.length`) for the bar's `N mcp`. */
+  mcpServers?: number
+  /** Epoch ms when this TUI session started (set once at store creation; never
+   *  patched from the wire) — drives the status-bar session duration. */
+  startedAt?: number
 }
 
 /** Startup catalog (tools/skills/MCP) for the home-screen panel (item 9 / banner parity). */
@@ -287,6 +302,12 @@ function infoPatchFrom(d: SessionInfoPatchDecoded): Partial<SessionInfo> {
   if (pct !== undefined) patch.contextPercent = pct
   const comp = d.usage?.compressions ?? d.compressions
   if (comp !== undefined) patch.compressions = comp
+  if (d.usage?.cost_usd !== undefined) patch.costUsd = d.usage.cost_usd
+  // null = "update check not resolved yet" — leave the prior value alone.
+  if (typeof d.update_behind === 'number') patch.updateBehind = d.update_behind
+  if (d.update_command) patch.updateCommand = d.update_command
+  if (d.profile_name) patch.profileName = d.profile_name
+  if (d.mcp_servers) patch.mcpServers = d.mcp_servers.length
   return patch
 }
 
@@ -365,7 +386,9 @@ export function createSessionStore() {
     dashboard: false,
     dashboardAgent: undefined,
     status: undefined,
-    info: {},
+    // startedAt is set ONCE here (store creation ≈ session start) — the status
+    // bar's session-duration segment ticks from it; wire patches never carry it.
+    info: { startedAt: Date.now() },
     hint: undefined,
     catalog: undefined,
     modelItems: undefined,

ui-opentui/src/test/statusChrome.test.tsx

@@ -0,0 +1,239 @@
+/**
+ * Epic 1.3 — header/status chrome (Variant A dense single status bar).
+ * Layers covered:
+ *   1. schema: the new SessionInfo wire fields decode (and null/absence is safe)
+ *   2. store: applyInfo merges the new usage/chrome fields
+ *   3. pure logic: statusSegments width table (priority drop order) + the
+ *      ctx/cmp threshold levels + compact formatters
+ *   4. frames: the bar renders the dense segment layout with separators, drops
+ *      tail segments when narrow, and the update notice borrows the line
+ */
+import { Option } from 'effect'
+import { describe, expect, test } from 'vitest'
+
+import { decodeSessionInfoPatch } from '../boundary/schema/SessionInfo.ts'
+import { createSessionStore, type SessionStore } from '../logic/store.ts'
+import { cmpLevel, ctxLevel, fmtShortDuration, fmtTokens, StatusBar, statusSegments } from '../view/statusBar.tsx'
+import { ThemeProvider } from '../view/theme.tsx'
+import { captureFrame, renderProbe } from './lib/render.ts'
+
+// ── 1. schema ────────────────────────────────────────────────────────────
+
+describe('SessionInfoPatchSchema — Epic 1.3 wire fields', () => {
+  test('decodes the new chrome fields (update/profile/mcp/cost)', () => {
+    const decoded = decodeSessionInfoPatch({
+      model: 'anthropic/claude-opus-4-8',
+      update_behind: 3,
+      update_command: 'hermes update',
+      profile_name: 'researcher',
+      mcp_servers: [{ name: 'railway' }, { name: 'beeper' }],
+      usage: { context_percent: 42, context_used: 84_000, cost_usd: 0.41, compressions: 2 }
+    })
+    expect(Option.isSome(decoded)).toBe(true)
+    if (Option.isSome(decoded)) {
+      expect(decoded.value.update_behind).toBe(3)
+      expect(decoded.value.update_command).toBe('hermes update')
+      expect(decoded.value.profile_name).toBe('researcher')
+      expect(decoded.value.mcp_servers).toHaveLength(2)
+      expect(decoded.value.usage?.cost_usd).toBe(0.41)
+    }
+  })
+
+  test('update_behind: null (check not resolved yet) decodes — None-safe', () => {
+    const decoded = decodeSessionInfoPatch({ model: 'm', update_behind: null, update_command: '' })
+    expect(Option.isSome(decoded)).toBe(true)
+    if (Option.isSome(decoded)) expect(decoded.value.update_behind).toBeNull()
+  })
+
+  test('all new fields absent still decodes (every key optional)', () => {
+    expect(Option.isSome(decodeSessionInfoPatch({ model: 'm' }))).toBe(true)
+  })
+})
+
+// ── 2. store applyInfo ───────────────────────────────────────────────────
+
+describe('store.applyInfo — Epic 1.3 chrome merge', () => {
+  test('merges cost/update/profile/mcp into SessionInfo', () => {
+    const store = createSessionStore()
+    store.applyInfo({
+      model: 'opus',
+      update_behind: 4,
+      update_command: 'uv tool upgrade hermes',
+      profile_name: 'researcher',
+      mcp_servers: [{}, {}, {}],
+      usage: { cost_usd: 0.4129, context_percent: 42 }
+    })
+    expect(store.state.info.costUsd).toBeCloseTo(0.4129)
+    expect(store.state.info.updateBehind).toBe(4)
+    expect(store.state.info.updateCommand).toBe('uv tool upgrade hermes')
+    expect(store.state.info.profileName).toBe('researcher')
+    expect(store.state.info.mcpServers).toBe(3)
+  })
+
+  test('update_behind: null leaves the prior value alone (partial-patch rule)', () => {
+    const store = createSessionStore()
+    store.applyInfo({ update_behind: 2 })
+    store.applyInfo({ update_behind: null })
+    expect(store.state.info.updateBehind).toBe(2)
+  })
+
+  test('a usage patch with cost does not clobber unrelated chrome', () => {
+    const store = createSessionStore()
+    store.applyInfo({ model: 'opus', profile_name: 'researcher' })
+    store.applyInfo({ usage: { cost_usd: 0.1 } })
+    expect(store.state.info).toMatchObject({ model: 'opus', profileName: 'researcher', costUsd: 0.1 })
+  })
+
+  test('startedAt is seeded at store creation and never patched off the wire', () => {
+    const before = Date.now()
+    const store = createSessionStore()
+    expect(store.state.info.startedAt).toBeGreaterThanOrEqual(before)
+    const seeded = store.state.info.startedAt
+    store.applyInfo({ model: 'opus' })
+    expect(store.state.info.startedAt).toBe(seeded)
+  })
+})
+
+// ── 3. pure logic ────────────────────────────────────────────────────────
+
+describe('statusSegments — progressive disclosure table', () => {
+  test('full width shows everything', () => {
+    expect(statusSegments(220)).toEqual({
+      ctxDetail: true,
+      duration: true,
+      compressions: true,
+      cost: true,
+      profile: true,
+      bg: true,
+      mcp: true
+    })
+  })
+
+  test('segments drop in reverse priority as width shrinks: mcp → bg → profile → cost → duration/cmp → ctx detail', () => {
+    // each row: [width, expected visible flags]
+    const table: Array<[number, Partial<ReturnType<typeof statusSegments>>]> = [
+      [115, { mcp: false, bg: true }], // mcp drops first
+      [107, { mcp: false, bg: false, profile: true }], // then bg
+      [99, { profile: false, cost: true }], // then profile
+      [91, { cost: false, duration: true, compressions: true }], // then cost
+      [79, { duration: false, compressions: false, ctxDetail: true }], // then duration/cmp
+      [71, { ctxDetail: false }] // finally the bar/token detail collapses to bare `42%`
+    ]
+    for (const [width, expected] of table) {
+      expect(statusSegments(width)).toMatchObject(expected)
+    }
+  })
+
+  test('pinned essentials are never gated: statusSegments only governs the tail', () => {
+    // even at absurdly narrow widths the table stays well-formed (booleans, no throw)
+    const segs = statusSegments(10)
+    expect(Object.values(segs).every(v => v === false)).toBe(true)
+  })
+})
+
+describe('threshold levels (spec 50/80/95 and cmp 5/10)', () => {
+  test('ctxLevel boundaries', () => {
+    expect(ctxLevel(0)).toBe('ok')
+    expect(ctxLevel(49)).toBe('ok')
+    expect(ctxLevel(50)).toBe('warn')
+    expect(ctxLevel(79)).toBe('warn')
+    expect(ctxLevel(80)).toBe('bad')
+    expect(ctxLevel(94)).toBe('bad')
+    expect(ctxLevel(95)).toBe('critical')
+    expect(ctxLevel(100)).toBe('critical')
+  })
+
+  test('cmpLevel boundaries', () => {
+    expect(cmpLevel(0)).toBe('ok')
+    expect(cmpLevel(4)).toBe('ok')
+    expect(cmpLevel(5)).toBe('warn')
+    expect(cmpLevel(9)).toBe('warn')
+    expect(cmpLevel(10)).toBe('bad')
+  })
+})
+
+describe('compact formatters', () => {
+  test('fmtTokens', () => {
+    expect(fmtTokens(950)).toBe('950')
+    expect(fmtTokens(84_321)).toBe('84k')
+    expect(fmtTokens(1_000_000)).toBe('1M')
+    expect(fmtTokens(1_250_000)).toBe('1.3M')
+  })
+
+  test('fmtShortDuration', () => {
+    expect(fmtShortDuration(42)).toBe('42s')
+    expect(fmtShortDuration(23 * 60)).toBe('23m')
+    expect(fmtShortDuration(65 * 60)).toBe('1h05m')
+  })
+})
+
+// ── 4. frames ────────────────────────────────────────────────────────────
+
+function seededStore(): SessionStore {
+  const store = createSessionStore()
+  store.apply({ type: 'gateway.ready' })
+  store.applyInfo({
+    model: 'anthropic/claude-opus-4-8',
+    reasoning_effort: 'high',
+    cwd: '/tmp/proj',
+    branch: 'main',
+    profile_name: 'researcher',
+    mcp_servers: [{}, {}],
+    usage: { context_percent: 42, context_used: 84_000, context_max: 200_000, cost_usd: 0.41, compressions: 2 }
+  })
+  return store
+}
+
+function bar(store: SessionStore) {
+  return () => (
+    <ThemeProvider theme={() => store.state.theme}>
+      <StatusBar store={store} />
+    </ThemeProvider>
+  )
+}
+
+describe('StatusBar frames (Variant A)', () => {
+  test('full width renders every segment with │ separators', async () => {
+    const frame = await captureFrame(bar(seededStore()), { width: 160, height: 3 })
+    expect(frame).toContain('claude-opus-4-8')
+    expect(frame).toContain('·high') // effort suffix
+    expect(frame).toContain('42%')
+    expect(frame).toContain('84k') // token-count detail
+    expect(frame).toContain('░') // the meter is partially filled at 42%
+    expect(frame).toContain('$0.41')
+    expect(frame).toContain('cmp 2')
+    expect(frame).toContain('researcher') // profile badge
+    expect(frame).toContain('2 mcp')
+    expect(frame).toContain('/tmp/proj (main)')
+    expect(frame).toContain('│')
+  })
+
+  test('narrow width drops the tail (no mcp/profile/cost) and compacts the context read-out', async () => {
+    const frame = await captureFrame(bar(seededStore()), { width: 70, height: 3 })
+    expect(frame).toContain('claude-opus-4-8') // pinned
+    expect(frame).toContain('42%') // pinned (compact)
+    expect(frame).not.toContain('█') // bar detail dropped
+    expect(frame).not.toContain('84k')
+    expect(frame).not.toContain('$0.41')
+    expect(frame).not.toContain('cmp 2')
+    expect(frame).not.toContain('researcher')
+    expect(frame).not.toContain('mcp')
+  })
+
+  test('update notice borrows the line and Esc dismisses it back to the normal bar', async () => {
+    const store = seededStore()
+    store.applyInfo({ update_behind: 3, update_command: 'hermes update' })
+    const probe = await renderProbe(bar(store), { width: 120, height: 3, kittyKeyboard: true })
+    try {
+      expect(probe.frame()).toContain('3 commits behind')
+      expect(probe.frame()).toContain('hermes update')
+      expect(probe.frame()).not.toContain('$0.41') // the notice replaced the segments
+      probe.keys.pressEscape()
+      await probe.settle()
+      const after = await probe.waitForFrame(f => f.includes('$0.41'))
+      expect(after).not.toContain('commits behind')
+    } finally {
+      probe.destroy()
+    }
+  })
+})

ui-opentui/src/view/header.tsx

@@ -1,8 +1,9 @@
 /**
- * Header — the top chrome line (spec v4 §2 `view/header.tsx`). Phase 2 skeleton:
+ * Header — the top chrome line (spec v4 §2 `view/header.tsx`). Variant A
+ * (v6 Epic 1.3, signed off): the header STAYS this minimal brand line —
  * brand · engine · ready/connecting, fully themed (`useTheme()`, NO hardcoded
- * styles — §7.5). Model / cwd / context% / cost land in Phase 5b once
- * `session.info` + `Usage` are wired.
+ * styles — §7.5). All session chrome (model/context/cost/duration/profile/mcp/
+ * cwd) lives in the dense bottom status bar (`statusBar.tsx`).
  */
 import { Show } from 'solid-js'
 

ui-opentui/src/view/statusBar.tsx

@@ -1,23 +1,110 @@
 /**
- * StatusBar — the persistent bottom chrome (spec §3; Ink's `appChrome.tsx`
- * StatusRule, item 14). One themed row pinned below the input zone:
+ * StatusBar — Variant A dense single status bar (v6 Epic 1.3; signed-off design).
+ * The header stays the minimal brand line; EVERYTHING else lives here, one
+ * themed row pinned above the composer:
  *
- *   ● model ·effort   ████░░░░ 42%                              ~/dir (branch)
+ *   ● model ·effort │ ███░░ 42% 84k │ $0.41 · 23m · cmp 2 │ profile │ 2 mcp │ …/cwd (branch)
  *
- * Fields are sourced from `store.state.info` (the `session.info` event +
- * session.create/resume result; see store `SessionInfo`). Width-aware (Ink's
- * `statusRuleWidths` progressive disclosure): the context bar drops on narrow
- * terminals and the cwd is left-truncated (`…/tail`) so the row NEVER wraps or
- * clips. Read-only chrome — no input handling here.
+ * Progressive disclosure (Ink's `statusRuleWidths` idiom): the dot+model and
+ * the context % are PINNED; the tail segments drop whole as columns shrink, in
+ * reverse priority — mcp → bg → profile → cost → duration/cmp → token/bar
+ * detail — and the cwd left-truncates into whatever remains. `statusSegments`
+ * is the pure width→visibility table (table-tested); nothing truncates
+ * mid-segment, so the row NEVER wraps or clips.
+ *
+ * A pending update (`info.update_behind > 0`) BORROWS the whole line as a
+ * transient notice (Variant A decision — no permanent transcript row); it
+ * dismisses on Esc or after NOTICE_TTL_MS.
+ *
+ * Parity notes (data that does not reach this TUI yet — reported, not faked):
+ *   - `N bg` (background tasks): the OpenTUI store has no background-task
+ *     tracking (Ink counts `prompt.background` task_ids + `background.complete`
+ *     locally); the segment slot exists in `statusSegments` but renders nothing.
+ *   - `display.show_cost`: Ink reads it from its `config.get` polling loop,
+ *     which this TUI doesn't have — cost shows whenever `usage.cost_usd` is
+ *     present instead.
+ *
+ * Read-only chrome — the only input handled is Esc-to-dismiss for the notice.
  */
-import { useDimensions } from './dimensions.tsx'
-import { createMemo, Show } from 'solid-js'
+import { useKeyboard } from '@opentui/solid'
+import { createEffect, createMemo, createSignal, onCleanup, Show } from 'solid-js'
 
-import { useTheme } from './theme.tsx'
 import type { SessionStore } from '../logic/store.ts'
+import { useDimensions } from './dimensions.tsx'
+import { elapsedSeconds, useElapsedTick } from './elapsed.ts'
+import { useTheme } from './theme.tsx'
 
 const HOME = process.env.HOME ?? ''
-const CTX_BAR_CELLS = 8
+const CTX_BAR_CELLS = 5
+const SEP = ' │ '
+const DOT_SEP = ' · '
+/** How long the transient update notice may borrow the bar line. */
+const NOTICE_TTL_MS = 30_000
+
+// ── pure, table-tested width/threshold logic ────────────────────────────
+
+/** Which tail segments are visible at a given column count. Drop order as the
+ *  terminal narrows (reverse priority, spec Epic 1.3): mcp → bg → profile →
+ *  cost → duration/cmp → ctxDetail (bar+token count collapse to a bare `42%`).
+ *  Dot+model and the context % are pinned and never gated here. */
+export interface StatusSegments {
+  /** Full `███░░ 42% 84k` read-out; false → compact bare `42%`. */
+  ctxDetail: boolean
+  duration: boolean
+  compressions: boolean
+  cost: boolean
+  profile: boolean
+  /** Background-tasks count — reserved; no store data feeds it yet (see header). */
+  bg: boolean
+  mcp: boolean
+}
+
+export function statusSegments(cols: number): StatusSegments {
+  const w = Math.max(1, Math.floor(cols || 1))
+  return {
+    ctxDetail: w >= 72,
+    duration: w >= 80,
+    compressions: w >= 80,
+    cost: w >= 92,
+    profile: w >= 100,
+    bg: w >= 108,
+    mcp: w >= 116
+  }
+}
+
+/** Context-pressure level for the bar/% colour (spec thresholds 50/80/95). */
+export type CtxLevel = 'ok' | 'warn' | 'bad' | 'critical'
+export function ctxLevel(pct: number): CtxLevel {
+  if (pct >= 95) return 'critical'
+  if (pct >= 80) return 'bad'
+  if (pct >= 50) return 'warn'
+  return 'ok'
+}
+
+/** Compression-count level (spec: warn ≥5, error ≥10). */
+export type CmpLevel = 'ok' | 'warn' | 'bad'
+export function cmpLevel(n: number): CmpLevel {
+  if (n >= 10) return 'bad'
+  if (n >= 5) return 'warn'
+  return 'ok'
+}
+
+/** Compact token count: 84321 → `84k`, 1_250_000 → `1.3M`, 950 → `950`. */
+export function fmtTokens(n: number): string {
+  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1).replace(/\.0$/, '')}M`
+  if (n >= 1_000) return `${Math.round(n / 1_000)}k`
+  return `${Math.max(0, Math.round(n))}`
+}
+
+/** Compact session duration: 42 → `42s`, 23*60 → `23m`, 65*60 → `1h05m`. */
+export function fmtShortDuration(seconds: number): string {
+  const s = Math.max(0, Math.floor(seconds))
+  if (s < 60) return `${s}s`
+  if (s < 3600) return `${Math.floor(s / 60)}m`
+  return `${Math.floor(s / 3600)}h${String(Math.floor((s % 3600) / 60)).padStart(2, '0')}m`
+}
+
+// ── local formatting helpers ────────────────────────────────────────────
 
 /** `anthropic/claude-opus-4-8` → `claude-opus-4-8`; trims the provider prefix (Ink shortModelLabel). */
 function shortModel(model: string): string {
@@ -46,7 +133,13 @@ function truncLeft(s: string, max: number): string {
   return s.length <= max ? s : '…' + s.slice(s.length - max + 1)
 }
 
-/** A unicode meter: `████░░░░` filled to `pct`% over `width` cells (Ink ctxBar). */
+/** Keep the HEAD of a string, suffixing with `…` when it must be clipped. */
+function truncRight(s: string, max: number): string {
+  if (max <= 1) return s.length > max ? '…' : s
+  return s.length <= max ? s : s.slice(0, max - 1) + '…'
+}
+
+/** A unicode meter: `███░░` filled to `pct`% over `width` cells (Ink ctxBar). */
 function ctxBar(pct: number, width: number): string {
   const filled = Math.max(0, Math.min(width, Math.round((pct / 100) * width)))
   return '█'.repeat(filled) + '░'.repeat(width - filled)
@@ -56,21 +149,50 @@ export function StatusBar(props: { store: SessionStore }) {
   const theme = useTheme()
   const dims = useDimensions()
   const info = () => props.store.state.info
+  const tick = useElapsedTick()
 
-  // Context-bar colour escalates with pressure (Ink ctxBarColor good→warn→bad→critical).
-  const ctxColor = (pct: number) =>
-    pct >= 92
+  const ctxColorOf = (pct: number) => {
+    const level = ctxLevel(pct)
+    return level === 'critical'
       ? theme().color.statusCritical
-      : pct >= 80
+      : level === 'bad'
         ? theme().color.statusBad
-        : pct >= 60
+        : level === 'warn'
           ? theme().color.statusWarn
           : theme().color.statusGood
+  }
+  const cmpColorOf = (n: number) => {
+    const level = cmpLevel(n)
+    return level === 'bad' ? theme().color.error : level === 'warn' ? theme().color.warn : theme().color.muted
+  }
 
   const dot = () => (info().running ? '◐' : props.store.state.ready ? '●' : '○')
   const dotColor = () =>
     info().running ? theme().color.statusWarn : props.store.state.ready ? theme().color.statusGood : theme().color.muted
 
+  const segs = createMemo(() => statusSegments(dims().width))
+
+  // ── transient update notice (borrows the whole line; Esc / TTL dismisses) ──
+  const [dismissed, setDismissed] = createSignal(false)
+  const noticeText = createMemo(() => {
+    const behind = info().updateBehind
+    if (dismissed() || behind === undefined || behind <= 0) return ''
+    const cmd = info().updateCommand
+    const base = `↑ hermes is ${behind} commit${behind === 1 ? '' : 's'} behind`
+    return `${base}${cmd ? ` — update: ${cmd}` : ''}${SEP}Esc to dismiss`
+  })
+  createEffect(() => {
+    if (!noticeText()) return
+    const timer = setTimeout(() => setDismissed(true), NOTICE_TTL_MS)
+    onCleanup(() => clearTimeout(timer))
+  })
+  // Dismiss-only handler: never swallows Esc from overlays/composer (they keep
+  // their own handlers); dismissing the notice alongside is benign.
+  useKeyboard(key => {
+    if (key.name === 'escape' && noticeText()) setDismissed(true)
+  })
+
+  // ── segment texts (each '' when hidden/absent — also feeds the width budget) ──
   const model = () => {
     const m = info().model
     return m ? shortModel(m) : ''
@@ -78,15 +200,48 @@ export function StatusBar(props: { store: SessionStore }) {
   const effort = () => effortSuffix(info().effort, info().fast)
   const pct = () => info().contextPercent
 
-  // Progressive disclosure budget (the row is `width - 2` after the box padding).
-  // left = dot+space+model+effort ; the context bar shows only when there's room.
-  const showBar = createMemo(() => pct() !== undefined && dims().width >= 64)
-  const ctxText = () => {
+  const ctxText = createMemo(() => {
     const p = pct()
-    return showBar() && p !== undefined ? `${ctxBar(p, CTX_BAR_CELLS)} ${p}%` : ''
-  }
+    if (p === undefined) return ''
+    if (!segs().ctxDetail) return `${p}%`
+    const used = info().contextUsed
+    return `${ctxBar(p, CTX_BAR_CELLS)} ${p}%${used !== undefined ? ` ${fmtTokens(used)}` : ''}`
+  })
 
-  // Right side: cwd (branch), left-truncated to whatever the left side leaves.
+  const costText = createMemo(() => {
+    const c = info().costUsd
+    return segs().cost && c !== undefined ? `$${c.toFixed(2)}` : ''
+  })
+  const durationText = createMemo(() => {
+    const started = info().startedAt
+    if (!segs().duration || !started || !model()) return ''
+    tick() // re-derive once per second while shown
+    return fmtShortDuration(elapsedSeconds(started))
+  })
+  const cmpCount = () => info().compressions ?? 0
+  const cmpText = createMemo(() => (segs().compressions && cmpCount() > 0 ? `cmp ${cmpCount()}` : ''))
+  /** cost · duration · cmp as ONE bar segment (the spec's `$0.41 · 23m · cmp 2`). */
+  const meterText = createMemo(() => [costText(), durationText(), cmpText()].filter(Boolean).join(DOT_SEP))
+
+  const profileText = createMemo(() => {
+    const p = info().profileName
+    return segs().profile && p && p !== 'default' && p !== 'custom' ? p : ''
+  })
+  const mcpText = createMemo(() => {
+    const n = info().mcpServers ?? 0
+    return segs().mcp && n > 0 ? `${n} mcp` : ''
+  })
+
+  // Width budget for the right-aligned cwd: total minus box padding minus the
+  // plain-text width of every visible left segment (all monospace-1-col chars).
+  const leftLen = createMemo(() => {
+    let len = 1 // dot
+    if (model()) len += 1 + model().length + effort().length
+    for (const seg of [ctxText(), meterText(), profileText(), mcpText()]) {
+      if (seg) len += SEP.length + seg.length
+    }
+    return len
+  })
   const cwdFull = createMemo(() => {
     const cwd = info().cwd
     const c = cwd ? shortCwd(cwd) : ''
@@ -94,8 +249,10 @@ export function StatusBar(props: { store: SessionStore }) {
     return info().branch ? `${c} (${info().branch})` : c
   })
   const rightText = createMemo(() => {
-    const leftLen = 2 + model().length + effort().length + (showBar() ? ctxText().length + 3 : 0)
-    const budget = dims().width - 2 - leftLen - 2 // box padding + a 2-col gap
+    // dims() is the TERMINAL width; the bar's row is narrower by the app shell's
+    // horizontal padding (2) + this box's own padding (2), and we keep a 2-col
+    // gap so the cwd never butts against the left segments.
+    const budget = dims().width - 4 - leftLen() - 2
     return budget > 4 ? truncLeft(cwdFull(), budget) : ''
   })
 
@@ -109,35 +266,76 @@ export function StatusBar(props: { store: SessionStore }) {
         paddingRight: 1
       }}
     >
-      {/* left: turn/connection dot + model + effort + context bar */}
-      <box style={{ flexShrink: 0, flexDirection: 'row' }}>
-        <text selectable={false}>
-          <span style={{ fg: dotColor() }}>{dot()}</span>
-          <Show when={model()}>
-            <span style={{ fg: theme().color.statusFg }}>{` ${model()}`}</span>
-            <span style={{ fg: theme().color.muted }}>{effort()}</span>
-          </Show>
-          <Show when={showBar()}>
-            {/* a dim divider segments the bar into scannable fields (item 8).
-                showBar() already guarantees pct() is defined; `?? 0` only
-                satisfies the type and is never reached. */}
-            <span style={{ fg: theme().color.border }}>{'  │  '}</span>
-            <span style={{ fg: ctxColor(pct() ?? 0) }}>{ctxBar(pct() ?? 0, CTX_BAR_CELLS)}</span>
-            <span style={{ fg: theme().color.statusFg }}>{` ${pct()}%`}</span>
-          </Show>
-        </text>
-      </box>
-
-      {/* spacer pushes the cwd to the right edge */}
-      <box style={{ flexGrow: 1, minWidth: 0 }} />
-
-      {/* right: cwd (branch), pre-truncated so the row never wraps */}
-      <Show when={rightText()}>
+      <Show
+        when={!noticeText()}
+        fallback={
+          // the update notice borrows the WHOLE line (Variant A) — warn-tinted,
+          // head-truncated so the Esc hint clips last only on absurd widths.
+          <text selectable={false}>
+            <span style={{ fg: theme().color.warn }}>{truncRight(noticeText(), Math.max(1, dims().width - 4))}</span>
+          </text>
+        }
+      >
+        {/* left: pinned dot+model, then the priority-ordered tail segments */}
         <box style={{ flexShrink: 0, flexDirection: 'row' }}>
           <text selectable={false}>
-            <span style={{ fg: theme().color.muted }}>{rightText()}</span>
+            <span style={{ fg: dotColor() }}>{dot()}</span>
+            <Show when={model()}>
+              <span style={{ fg: theme().color.statusFg }}>{` ${model()}`}</span>
+              <span style={{ fg: theme().color.muted }}>{effort()}</span>
+            </Show>
+            <Show when={ctxText()}>
+              <span style={{ fg: theme().color.border }}>{SEP}</span>
+              {/* ctxText() truthy guarantees pct() is defined; `?? 0` only satisfies the type. */}
+              <Show when={segs().ctxDetail} fallback={<span style={{ fg: ctxColorOf(pct() ?? 0) }}>{ctxText()}</span>}>
+                <span style={{ fg: ctxColorOf(pct() ?? 0) }}>{ctxBar(pct() ?? 0, CTX_BAR_CELLS)}</span>
+                <span style={{ fg: theme().color.statusFg }}>{` ${pct()}%`}</span>
+                <Show when={info().contextUsed !== undefined}>
+                  <span style={{ fg: theme().color.muted }}>{` ${fmtTokens(info().contextUsed ?? 0)}`}</span>
+                </Show>
+              </Show>
+            </Show>
+            <Show when={meterText()}>
+              <span style={{ fg: theme().color.border }}>{SEP}</span>
+              <Show when={costText()}>
+                <span style={{ fg: theme().color.muted }}>{costText()}</span>
+              </Show>
+              <Show when={costText() && durationText()}>
+                <span style={{ fg: theme().color.muted }}>{DOT_SEP}</span>
+              </Show>
+              <Show when={durationText()}>
+                <span style={{ fg: theme().color.muted }}>{durationText()}</span>
+              </Show>
+              <Show when={(costText() || durationText()) && cmpText()}>
+                <span style={{ fg: theme().color.muted }}>{DOT_SEP}</span>
+              </Show>
+              <Show when={cmpText()}>
+                <span style={{ fg: cmpColorOf(cmpCount()) }}>{cmpText()}</span>
+              </Show>
+            </Show>
+            <Show when={profileText()}>
+              <span style={{ fg: theme().color.border }}>{SEP}</span>
+              <span style={{ fg: theme().color.accent }}>{profileText()}</span>
+            </Show>
+            {/* `N bg` would slot here (segs().bg) — no store data feeds it yet (see header). */}
+            <Show when={mcpText()}>
+              <span style={{ fg: theme().color.border }}>{SEP}</span>
+              <span style={{ fg: theme().color.muted }}>{mcpText()}</span>
+            </Show>
           </text>
         </box>
+
+        {/* spacer pushes the cwd to the right edge */}
+        <box style={{ flexGrow: 1, minWidth: 0 }} />
+
+        {/* right: cwd (branch), pre-truncated so the row never wraps */}
+        <Show when={rightText()}>
+          <box style={{ flexShrink: 0, flexDirection: 'row' }}>
+            <text selectable={false}>
+              <span style={{ fg: theme().color.muted }}>{rightText()}</span>
+            </text>
+          </box>
+        </Show>
       </Show>
     </box>
   )