diff --git a/.changeset/vertical-rail-detailed-rows.md b/.changeset/vertical-rail-detailed-rows.md
new file mode 100644
index 000000000..950b2f7ad
--- /dev/null
+++ b/.changeset/vertical-rail-detailed-rows.md
@@ -0,0 +1,20 @@
+---
+"aicodeman": patch
+---
+
+Vertical tab rail: detailed rows, and a rename cancel that no longer wipes the name.
+
+The vertical rail (Tab Orientation → Vertical) now draws the same per-session
+line the home screen and the rich sidebar draw — when the session was created,
+how long it has been in the state it is in, the folder it runs in, and a status
+pill — instead of just the name. New per-device setting **Vertical Rail Rows**
+(`tabRailDetail`, App Settings → Appearance → Tabs) with `Detailed` as the
+default and `Simple (name only)` as the opt-out. A rail that has never been
+sized now opens at 320px (the existing Wide preset) so the line fits; a narrower
+rail sheds the created stamp below 288px and falls back to simple rows below
+240px.
+
+Also fixes a data-loss bug in the inline tab rename that predates the rail:
+pressing Escape cleared the input and blurred it, and the blur handler commits —
+so cancelling a rename stored an EMPTY session name and the tab fell back to its
+folder label. Escape now cancels without a request, in every layout.
diff --git a/CLAUDE.md b/CLAUDE.md
index 35e0addc9..4b4842a39 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -270,7 +270,7 @@ Frontend JS modules have `@fileoverview` with `@dependency`/`@loadorder` tags. L
 
 **Mobile tab strip scrolling** (issue #257): under 768px the tab strip is a horizontal scroller (desktop wraps to a second row instead), so the active tab can sit off-screen. Three rules keep it reachable and they only work together: `_updateActiveTabImmediate()` scrolls the selected tab into view via `computeTabScrollLeft()` (pure, in constants.js) using **rect math on the strip's own `scrollLeft`**, never `scrollIntoView()`, which would also scroll the document under a fixed header; `_fullRenderSessionTabs()` **restores `scrollLeft`** across the `innerHTML` rebuild, since ambient rebuilds (a task badge appearing, a session created elsewhere) otherwise snap a mid-swipe strip back to 0; and it re-reveals the active tab **only when it changed** (`_lastRenderedActiveTabId`), so browsing the far end of the strip is not undone by background renders. ⚠️ **The ACTIVE tab is the only one with action icons, and on a phone they can eat it**: `.session-tab.active .tab-name` reserves `min-width: 44px` in the ≤430px block, because a short session name rendered a 13px label against a 50px gear+close cluster, putting the tab's geometric CENTRE on the gear, so a thumb aiming at the tab opened Session Options instead of switching (measured at 360/393/430px; only long names cleared it). ⚠️ **The floor is set by the 10th tab onward, not by the tabs you can see**: `.tab-number` renders only for `_tabIdx < 9`, so tab 10 loses 16px + a gap off its left and its centre sits 10px further right. The centre clears the icons when `reserved > icons + rightEdge - leftRunUp - gap` (= 50 + 9 - 17 - 4 = **38px**), hit-testing snaps to whole pixels so 39px still lands on the gear, and the practical floor is 40px — a NUMBERED tab clears it at 20px, which is exactly why reasoning from the tabs on screen would put the centre back on the gear. `test/mobile-tab-tap-zones.test.ts` recomputes that inequality from the stylesheet, so widening the gear or the padding fails there rather than on a phone. The guarantee is centre-off-the-ICONS, not centre-inside-the-label (on a numberless tab it lands in the gap between them, which still switches). Non-active tabs keep their icons hidden and stay tappable end to end. ⚠️ Mobile no longer hoists the active session to the front of the strip: that reordering ran on full renders only, so tab order flipped depending on which render path fired, and it renumbered the Alt+N badges. Scroll-into-view replaces it; do not reintroduce it.
 
-**Session list layout: header strip or left sidebar** (`sessionListLayout`, App Settings → Appearance → Tabs, default `header`; per-device policy — it IS in `SettingsUpdateSchema` and persists server-side, but `displayKeys` makes a device keep its own value): with many sessions the horizontal strip stops being scannable, so the list can move into a vertical `<aside>` with a filter box and a live count, collapsible to a 44px rail (`--sidebar-width` 260 / `--sidebar-width-collapsed` 44) via **Alt+B** (`toggleSessionSidebar`; Alt, not Ctrl+B, which must reach tmux/readline in the terminal). ⚠️ **There is ONE `#sessionTabs` element and it is MOVED between hosts** (`#sessionTabsHost` in the header, `#sessionSidebarList` in the aside, `#tabRail` for the vertical rail below), never a second list — so every render path, drag-reorder handler and Alt+N index keeps working unchanged. Exactly TWO functions reparent it and they must run in this order: `applySessionListLayout()` first (sidebar wins), then `applyTabOrientation()` (settings-ui.js), which moves the tabs into `#tabRail` only when the sidebar does not own them. ⚠️ It sets `data-session-list` / `data-sidebar` on `<html>` and must run BEFORE `applyTabWrapSettings()`, which is the one owner of `tabs-two-rows`/`tabs-show-folder` and reads those attributes. ⚠️ **The vertical tab rail** (`tabOrientation`/`tabRailWidth`/`sessionSidebarFontSize`, all per-device display keys that ARE in the schema, like `sessionListLayout`) is a SECOND vertical list next to the sidebar: the orientation setting is silently ignored while the sidebar layout is chosen, desktop/tablet only (`resolveTabOrientation` forces horizontal on mobile), resizable via `tab-rail-resize.js` (which owns terminal refits during the drag). ⚠️ **Axis decisions must use `_isVerticalTabList()`** (sidebar OR rail), never `isSessionSidebarActive()` alone: the rail leaves `data-session-list` at `header`, and the sidebar-only predicate shipped four rail bugs at once (drag insertion side read from clientX, active tab never scrolled into view, floating windows anchored below tabs instead of beside them, connector redraws skipped on rail scroll). The pre-paint script stamps `data-tab-orientation` (+ `--tab-rail-width`) like it stamps the sidebar keys, or vertical mode flashes through the header strip; the name font size defaults to 12px, the sidebar's historical size, so untouched installs are never restyled. ⚠️ Leaving sidebar mode **clears `_sidebarFilter`**: the filter box only exists in the aside, so a stale filter would hide sessions from the header strip with no reachable control to clear it. ⚠️ On handhelds the aside is an off-canvas overlay rather than a docked rail, and a closed drawer keeps `display: flex`, so it is marked `inert` + `aria-hidden` (`_isSessionSidebarOverlay()`) or its filter box and ~4 tab stops per session stay in the tab order; the DOCKED desktop rail must never be inerted, its rows are still clickable. The desktop home rail (`home-sessions.js`) defers to it, since both dock the session list flush left.
+**Session list layout: header strip or left sidebar** (`sessionListLayout`, App Settings → Appearance → Tabs, default `header`; per-device policy — it IS in `SettingsUpdateSchema` and persists server-side, but `displayKeys` makes a device keep its own value): with many sessions the horizontal strip stops being scannable, so the list can move into a vertical `<aside>` with a filter box and a live count, collapsible to a 44px rail (`--sidebar-width` 260 / `--sidebar-width-collapsed` 44) via **Alt+B** (`toggleSessionSidebar`; Alt, not Ctrl+B, which must reach tmux/readline in the terminal). ⚠️ **There is ONE `#sessionTabs` element and it is MOVED between hosts** (`#sessionTabsHost` in the header, `#sessionSidebarList` in the aside, `#tabRail` for the vertical rail below), never a second list — so every render path, drag-reorder handler and Alt+N index keeps working unchanged. Exactly TWO functions reparent it and they must run in this order: `applySessionListLayout()` first (sidebar wins), then `applyTabOrientation()` (settings-ui.js), which moves the tabs into `#tabRail` only when the sidebar does not own them. ⚠️ It sets `data-session-list` / `data-sidebar` on `<html>` and must run BEFORE `applyTabWrapSettings()`, which is the one owner of `tabs-two-rows`/`tabs-show-folder` and reads those attributes. ⚠️ **The vertical tab rail** (`tabOrientation`/`tabRailWidth`/`sessionSidebarFontSize`, all per-device display keys that ARE in the schema, like `sessionListLayout`) is a SECOND vertical list next to the sidebar: the orientation setting is silently ignored while the sidebar layout is chosen, desktop/tablet only (`resolveTabOrientation` forces horizontal on mobile), resizable via `tab-rail-resize.js` (which owns terminal refits during the drag). ⚠️ **Detailed rows are a property of a vertical LIST, not of one surface** (`sessionListLayout: 'sidebar-rich'` for the sidebar, `tabRailDetail: 'rich'|'simple'` for the rail, rail default **rich**): both draw the home screen's per-session line (`created 3d ago · working 12m`) plus a status pill, from the SAME row model (`_sidebarRichRow`/`_sidebarRichMetaHTML` in app.js, classified by `_mobileOverviewState`/`_mobileOverviewSince`), and the render paths ask ONE gate, `isRichTabRows()` (= `isSessionSidebarRich() || isTabRailRich()`). ⚠️ Detail rides on its own attribute (`data-sidebar-detail` / `data-tab-rail-detail`) so every existing `[data-session-list="sidebar"]` / `[data-tab-orientation='vertical']` rule keeps matching both variants untouched; a flip of detail ALONE still needs a full render (the stamps line is emitted by the row template, not toggled by CSS) and must re-run `applyTabWrapSettings()`, which owns the folder line and is now rail-aware. ⚠️ The rich CSS rules carry a rail twin as a COMMA-GROUPED selector, never `:is()` (an `:is()` list takes its most specific argument, which would lift the sidebar arm from (0,3,1) to the rail's (0,5,1)). ⚠️ Width is the whole reason there are thresholds: the rich sidebar is 300px (`--sidebar-width-rich`) and a rail that has never been sized defaults to **320** (`RICH_DEFAULT_WIDTH`, the existing Wide preset) instead of 256, because at 256 the stamps line ellipsizes mid-word; a user-narrowed rail drops the created stamp below 288 (`tab-rail-tight`, CSS only) and drops rich rows entirely below 240 (`tab-rail-compact`, which re-renders). A stored width is never overridden. ⚠️ Only detailed rows carry stamps that go stale with no event behind them, so `_startSidebarRichClock()` (20s, rewrites text in place — a re-render would restart every row's animation) must be armed and disarmed by BOTH `applySessionListLayout()` and `applyTabOrientation()`. ⚠️ **Axis decisions must use `_isVerticalTabList()`** (sidebar OR rail), never `isSessionSidebarActive()` alone: the rail leaves `data-session-list` at `header`, and the sidebar-only predicate shipped four rail bugs at once (drag insertion side read from clientX, active tab never scrolled into view, floating windows anchored below tabs instead of beside them, connector redraws skipped on rail scroll). The pre-paint script stamps `data-tab-orientation` (+ `--tab-rail-width`) like it stamps the sidebar keys, or vertical mode flashes through the header strip; the name font size defaults to 12px, the sidebar's historical size, so untouched installs are never restyled. ⚠️ Leaving sidebar mode **clears `_sidebarFilter`**: the filter box only exists in the aside, so a stale filter would hide sessions from the header strip with no reachable control to clear it. ⚠️ On handhelds the aside is an off-canvas overlay rather than a docked rail, and a closed drawer keeps `display: flex`, so it is marked `inert` + `aria-hidden` (`_isSessionSidebarOverlay()`) or its filter box and ~4 tab stops per session stay in the tab order; the DOCKED desktop rail must never be inerted, its rows are still clickable. The desktop home rail (`home-sessions.js`) defers to it, since both dock the session list flush left.
 
 **Phone overview home screen** (`mobile-overview.js`, phones only, per-device `mobileOverviewEnabled`, default ON): under 430px the "C" logo shows a session overview (NEEDS YOU / CURRENT SESSIONS / PAST SESSIONS) instead of the welcome overlay; tablet and desktop are unchanged. The branch lives in `showWelcome()`/`hideWelcome()` (terminal-ui.js) behind `shouldUseMobileOverview()`, which is **width-driven** (`getDeviceType() === 'mobile'`) because this is a layout decision, unlike the settings namespace which stays handheld-based. ⚠️ The container ships with the `hidden` attribute and only this module removes it: never give `.mobile-overview` a bare `display` rule, since desktop does not load `mobile.css` (`media="(max-width: 1023px)"`) and would then render it unstyled. Live re-renders ride on the tail of `_renderSessionTabsImmediate()` (every state change it needs already funnels there); PAST rows come from one `_fetchUnifiedSessions(60)` per home-screen visit and resume through the shared `resumeHistorySession()`, so they behave exactly like the welcome screen's Resume list. ⚠️ Two things must stay in lockstep with surfaces outside this module, because divergence reads as a bug rather than a style: the split Run button carries the **toolbar's own classes** (`btn-toolbar btn-run mode-<backend>` / `btn-run-gear`) so the per-backend gradient and the light-skin overrides apply unchanged (mobile.css must therefore set no `background`/`color` on it), and row status uses the **session-tab language** (green dot when fine, `pulse` while working, yellow blinking row when waiting for input, red blinking row when a question is pending, mirroring `tab-alert-idle`/`tab-alert-action`). The picker mirrors the toolbar run-mode menu (`setRunMode()` + `run()`, `openWebviewFromMenu()` for saved dashboards) and deliberately omits its Recent-Sessions block, since PAST SESSIONS is that. Status pills carry `data-i18n-skip` (generic words like "idle" collide with state strings elsewhere).
 
diff --git a/src/web/public/app.js b/src/web/public/app.js
index 52e97b149..73eee32cd 100644
--- a/src/web/public/app.js
+++ b/src/web/public/app.js
@@ -3826,6 +3826,38 @@ class CodemanApp {
     return root.dataset.sessionList === 'sidebar' && root.dataset.sidebarDetail === 'rich';
   }
 
+  /**
+   * True when the VERTICAL TAB RAIL (tabOrientation 'vertical') is showing the
+   * detailed rows: the same "created 3d ago · working 12m" line and status pill
+   * the rich sidebar and both home screens carry.
+   *
+   * A docked column is not a tab strip — that was the argument for the rich
+   * sidebar, and the rail is a docked column too, so it defaults to rich and
+   * `tabRailDetail: 'simple'` is the opt-out.
+   *
+   * The compact carve-out is not cosmetic: below 240px the rail already drops
+   * the row actions to a hover affordance, and three lines of stamps in a
+   * ~208px column ellipsize into noise. `_setTabRailWidth()` re-renders the
+   * tabs whenever that class flips, so this gate is re-read at the right moment.
+   */
+  isTabRailRich() {
+    const root = document.documentElement;
+    return (
+      root.getAttribute('data-tab-orientation') === 'vertical' &&
+      root.dataset.tabRailDetail === 'rich' &&
+      !root.classList.contains('tab-rail-compact')
+    );
+  }
+
+  /**
+   * The one gate the render paths ask: does THIS list draw detailed rows?
+   * Either vertical surface can, and neither can be on at once (the sidebar
+   * owns the tabs whenever it is active, which forces the rail off).
+   */
+  isRichTabRows() {
+    return this.isSessionSidebarRich() || this.isTabRailRich();
+  }
+
   /**
    * True where the sidebar is a MODAL off-canvas drawer over the terminal
    * instead of a docked column.
@@ -3999,7 +4031,7 @@ class CodemanApp {
       this.showHomeSessions?.();
     }
     // Only the rich rows carry stamps that go stale with no event behind them.
-    if (this.isSessionSidebarRich()) this._startSidebarRichClock();
+    if (this.isRichTabRows()) this._startSidebarRichClock();
     else this._stopSidebarRichClock();
   }
 
@@ -4116,13 +4148,14 @@ class CodemanApp {
   }
 
   /**
-   * The per-row model for a rich sidebar row: which state the session is in,
-   * when it was first created, and how long it has been in that state.
+   * The per-row model for a rich row (detailed sidebar or vertical tab rail):
+   * which state the session is in, when it was first created, and how long it
+   * has been in that state.
    *
    * Classification is `_mobileOverviewState()` and the state duration is
    * `_mobileOverviewSince()` (both mobile-overview.js), NOT re-derived here —
-   * the sidebar, the desktop home rail and the phone overview must never
-   * disagree about what "working" means or about which stamp measures it.
+   * the sidebar, the rail, the desktop home rail and the phone overview must
+   * never disagree about what "working" means or about which stamp measures it.
    *
    * Guarded like every other cross-file consumer in this app: a stale cached
    * mobile-overview.js must degrade to a row with no meta line, not throw and
@@ -4169,7 +4202,21 @@ class CodemanApp {
       parts.push(stamp(row.since.key, row.since.at, 'for', 'tab-meta-since'));
     }
     parts.push(`<span class="tab-pill tab-pill--${escapeHtml(row.state)}">${escapeHtml(row.pill)}</span>`);
-    return `<span class="tab-meta" data-i18n-skip>${parts.join('')}</span>`;
+    // Both absolute stamps ALSO on the line itself, not only on the two items.
+    // Below 288px the rail hides `.tab-meta-created` (the `tab-rail-tight`
+    // rule), and a tooltip on a `display: none` element has no hover target —
+    // so without this the created stamp is not merely shrunk, it is gone with
+    // no way to ask for it. The pill and the gaps around the stamps are the
+    // hover targets that remain; an item's own title still wins over this one
+    // where the item is visible.
+    const lineTitle = [
+      row.createdAt ? `First created: ${new Date(row.createdAt).toLocaleString()}` : '',
+      row.since && row.since.at ? `${row.since.key}: ${new Date(row.since.at).toLocaleString()}` : '',
+    ]
+      .filter(Boolean)
+      .join('  \u00B7  ');
+    const lineTitleAttr = lineTitle ? ` title="${escapeHtml(lineTitle)}"` : '';
+    return `<span class="tab-meta"${lineTitleAttr} data-i18n-skip>${parts.join('')}</span>`;
   }
 
   /** Same formatter as both home screens, so a duration is written the same way everywhere. */
@@ -4214,7 +4261,7 @@ class CodemanApp {
   _startSidebarRichClock() {
     if (this._sidebarRichClock) return;
     this._sidebarRichClock = setInterval(() => {
-      if (!this.isSessionSidebarRich()) {
+      if (!this.isRichTabRows()) {
         this._stopSidebarRichClock();
         return;
       }
@@ -4431,7 +4478,7 @@ class CodemanApp {
     if (canIncremental) {
       // Read once for the whole pass, like the full-rebuild path: this touches
       // the DOM and the loop below runs for every session on every SSE tick.
-      const richRows = this.isSessionSidebarRich();
+      const richRows = this.isRichTabRows();
       // Incremental update - only modify changed properties
       for (const [id, session] of this.sessions) {
         const tab = container.querySelector(`.session-tab[data-id="${id}"]`);
@@ -4740,9 +4787,9 @@ class CodemanApp {
     // into view replaces it.
     const parts = [];
     const tabOrder = this.sessionOrder;
-    // Read once, not per session: isSessionSidebarRich() touches the DOM and
+    // Read once, not per session: isRichTabRows() touches the DOM and
     // this loop runs for every tab on every full rebuild.
-    const richRows = this.isSessionSidebarRich();
+    const richRows = this.isRichTabRows();
     let _tabIdx = 0;
     for (const id of tabOrder) {
       const session = this.sessions.get(id);
@@ -4786,9 +4833,10 @@ class CodemanApp {
         ? (session.workingDir ? `${parsedName.prefix} (${session.workingDir})` : parsedName.prefix)
         : (session.workingDir || '');
 
-      // Rich sidebar rows only: the home screen's created/state stamps and a
-      // status pill. richRow is null in every other layout, and both helpers
-      // below collapse to '' — the header strip's markup is unchanged.
+      // Rich rows only (the detailed sidebar OR the vertical tab rail): the home
+      // screen's created/state stamps and a status pill. richRow is null in every
+      // other layout, and both helpers below collapse to '' — the header strip's
+      // markup is unchanged.
       const richRow = richRows ? this._sidebarRichRow(id, session) : null;
       const richMeta = this._sidebarRichMetaHTML(richRow);
       const richClass = richRow ? ` tab-state-${richRow.state}` : '';
diff --git a/src/web/public/constants.js b/src/web/public/constants.js
index 8fcc4c4b2..45579ca17 100644
--- a/src/web/public/constants.js
+++ b/src/web/public/constants.js
@@ -164,6 +164,9 @@ function resolveTabOrientation(input) {
 
 const TAB_RAIL_MIN_WIDTH = 208;
 const TAB_RAIL_DEFAULT_WIDTH = 256;
+/** Detailed rows carry a third line, and it ellipsizes at 256px — see the
+    rich sidebar's own 300px column. 320px is the existing Wide preset. */
+const TAB_RAIL_RICH_DEFAULT_WIDTH = 320;
 const TAB_RAIL_MAX_WIDTH = 360;
 
 function resolveTabRailWidth(input = {}) {
@@ -185,7 +188,9 @@ function resolveTabRailKeyboardWidth(input = {}) {
   let width;
   if (input.key === 'Home') width = TAB_RAIL_MIN_WIDTH;
   else if (input.key === 'End') width = TAB_RAIL_MAX_WIDTH;
-  else if (input.key === 'Enter') width = TAB_RAIL_DEFAULT_WIDTH;
+  // Enter resets to the caller's effective default (the rich rail's is the
+  // Wide preset, not 256 — see _defaultTabRailWidth); absent, the base default.
+  else if (input.key === 'Enter') width = Number(input.defaultWidth) || TAB_RAIL_DEFAULT_WIDTH;
   else if (input.key === 'ArrowLeft' || input.key === 'ArrowRight') {
     const direction = input.key === 'ArrowLeft' ? -1 : 1;
     width = (Number(input.currentWidth) || TAB_RAIL_DEFAULT_WIDTH) + direction * (input.shiftKey ? 32 : 8);
@@ -686,6 +691,7 @@ if (typeof window !== 'undefined') {
   };
   window.CodemanTabRail = {
     DEFAULT_WIDTH: TAB_RAIL_DEFAULT_WIDTH,
+    RICH_DEFAULT_WIDTH: TAB_RAIL_RICH_DEFAULT_WIDTH,
     MIN_WIDTH: TAB_RAIL_MIN_WIDTH,
     MAX_WIDTH: TAB_RAIL_MAX_WIDTH,
     resolveWidth: resolveTabRailWidth,
diff --git a/src/web/public/index.html b/src/web/public/index.html
index 2031f5e26..f48ca6410 100644
--- a/src/web/public/index.html
+++ b/src/web/public/index.html
@@ -65,7 +65,7 @@
        app.js, NOT the handheld storage-key test `m`. Use a different predicate
        here and boot will contradict this value, animating the drawer open by
        itself on every load between 768 and 1023px. -->
-  <script>try{var m=window.innerWidth<768||(('ontouchstart' in window||navigator.maxTouchPoints>0)&&window.innerWidth<1024);var k=m?'codeman-app-settings-mobile':'codeman-app-settings';var A=JSON.parse(localStorage.getItem(k)||'{}');var L=A.sessionListLayout;var F=Number(A.sessionSidebarFontSize);var solo=/^\/session\//.test(location.pathname);var C=localStorage.getItem('codeman-sidebar-collapsed');var S=(L==='sidebar'||L==='sidebar-rich')&&!solo;document.documentElement.dataset.sessionList=S?'sidebar':'header';document.documentElement.dataset.sidebarDetail=(S&&L==='sidebar-rich')?'rich':'simple';document.documentElement.dataset.sidebar=(C===null?window.innerWidth<1024:C==='1')?'collapsed':'expanded';var V=A.tabOrientation==='vertical'&&!S&&!solo&&window.innerWidth>=768;document.documentElement.dataset.tabOrientation=V?'vertical':'horizontal';var W=Number(A.tabRailWidth);if(V&&Number.isInteger(W)&&W>=208&&W<=360)document.documentElement.style.setProperty('--tab-rail-width',W+'px');if(Number.isInteger(F)&&F>=11&&F<=18)document.documentElement.style.setProperty('--session-sidebar-name-font-size',F+'px');}catch(e){document.documentElement.dataset.sessionList='header';document.documentElement.dataset.sidebarDetail='simple';document.documentElement.dataset.sidebar='expanded';document.documentElement.dataset.tabOrientation='horizontal';}</script>
+  <script>try{var m=window.innerWidth<768||(('ontouchstart' in window||navigator.maxTouchPoints>0)&&window.innerWidth<1024);var k=m?'codeman-app-settings-mobile':'codeman-app-settings';var A=JSON.parse(localStorage.getItem(k)||'{}');var L=A.sessionListLayout;var F=Number(A.sessionSidebarFontSize);var solo=/^\/session\//.test(location.pathname);var C=localStorage.getItem('codeman-sidebar-collapsed');var S=(L==='sidebar'||L==='sidebar-rich')&&!solo;document.documentElement.dataset.sessionList=S?'sidebar':'header';document.documentElement.dataset.sidebarDetail=(S&&L==='sidebar-rich')?'rich':'simple';document.documentElement.dataset.sidebar=(C===null?window.innerWidth<1024:C==='1')?'collapsed':'expanded';var V=A.tabOrientation==='vertical'&&!S&&!solo&&window.innerWidth>=768;document.documentElement.dataset.tabOrientation=V?'vertical':'horizontal';document.documentElement.dataset.tabRailDetail=(A.tabRailDetail==='simple')?'simple':'rich';var W=Number(A.tabRailWidth);if(V){if(Number.isInteger(W)&&W>=208&&W<=360)document.documentElement.style.setProperty('--tab-rail-width',W+'px');else if(document.documentElement.dataset.tabRailDetail!=='simple')document.documentElement.style.setProperty('--tab-rail-width','320px');}if(Number.isInteger(F)&&F>=11&&F<=18)document.documentElement.style.setProperty('--session-sidebar-name-font-size',F+'px');}catch(e){document.documentElement.dataset.sessionList='header';document.documentElement.dataset.sidebarDetail='simple';document.documentElement.dataset.sidebar='expanded';document.documentElement.dataset.tabOrientation='horizontal';document.documentElement.dataset.tabRailDetail='rich';}</script>
   <!-- Inline critical CSS for instant skeleton paint (before styles.css loads) -->
   <style>
     .loading-skeleton{display:flex;flex-direction:column;height:100vh;height:100dvh;background:var(--bg-dark,#11151c)}
@@ -1903,6 +1903,16 @@ <h2>Appearance</h2>
                       <option value="vertical">Vertical (side rail)</option>
                     </select>
                   </div>
+                  <div class="set-row has-field" data-search="tab rail detail rows created working idle status pill simple">
+                    <div class="set-row-text">
+                      <span class="set-row-label">Vertical Rail Rows</span>
+                      <span class="set-row-desc">Detailed rows carry the home screen's per-session line (created, how long it has been working or idle) and a status pill. Needs ~280px of rail; a rail narrower than 240px drops back to simple rows.</span>
+                    </div>
+                    <select id="appSettingsTabRailDetail" class="set-select">
+                      <option value="rich">Detailed</option>
+                      <option value="simple">Simple (name only)</option>
+                    </select>
+                  </div>
                   <div class="set-row has-field" data-search="tab rail width resize compact wide maximum">
                     <div class="set-row-text">
                       <span class="set-row-label">Vertical Rail Width</span>
diff --git a/src/web/public/session-ui.js b/src/web/public/session-ui.js
index ed014e3b7..ebdcbb9ee 100644
--- a/src/web/public/session-ui.js
+++ b/src/web/public/session-ui.js
@@ -1976,8 +1976,13 @@ Object.assign(CodemanApp.prototype, {
         e.preventDefault();
         input.blur();
       } else if (e.key === 'Escape') {
-        input.value = '';
-        input.blur();
+        // Cancel, never commit. This used to clear the field and blur, and the
+        // blur handler commits — so Escape RENAMED the session to an empty
+        // string (measured: the tab fell back to its folder name and the server
+        // stored ""), in every layout. cancelRename() marks the edit
+        // invalidated, so the blur that follows the input's removal is a no-op.
+        e.preventDefault();
+        cancelRename();
       }
     });
   },
diff --git a/src/web/public/settings-ui.js b/src/web/public/settings-ui.js
index 9d9a42bd0..005c94e68 100644
--- a/src/web/public/settings-ui.js
+++ b/src/web/public/settings-ui.js
@@ -403,9 +403,18 @@ Object.assign(CodemanApp.prototype, {
     document.getElementById('appSettingsTabOrientation').value =
       settings.tabOrientation ?? defaults.tabOrientation ?? 'horizontal';
     const tabRailWidth = window.CodemanTabRail?.resolveWidth({
-      width: settings.tabRailWidth ?? defaults.tabRailWidth ?? 256,
+      // Same default resolution as applyTabRailWidth(): a rail that has never
+      // been sized shows the width it is actually rendering at, which for
+      // detailed rows is the Wide preset rather than 256. The rich-aware
+      // default must come BEFORE the per-device defaults blob: the handheld
+      // blob carries tabRailWidth: 256, which applyTabRailWidth() never reads,
+      // so consulting it first showed a tablet's unsized rich rail as 256 while
+      // it rendered at 320 — and a routine Save then PERSISTED the 256.
+      width: settings.tabRailWidth ?? this._defaultTabRailWidth?.() ?? defaults.tabRailWidth ?? 256,
     }) ?? 256;
     this.syncTabRailWidthSetting?.(tabRailWidth);
+    document.getElementById('appSettingsTabRailDetail').value =
+      settings.tabRailDetail ?? defaults.tabRailDetail ?? 'rich';
     document.getElementById('appSettingsShowTabDetachButton').checked = settings.showTabDetachButton ?? defaults.showTabDetachButton ?? false;
     document.getElementById('appSettingsSessionListLayout').value =
       settings.sessionListLayout ?? defaults.sessionListLayout ?? 'header';
@@ -2041,6 +2050,7 @@ Object.assign(CodemanApp.prototype, {
       tabTwoRows: document.getElementById('appSettingsTabTwoRows').checked,
       tabOrientation: document.getElementById('appSettingsTabOrientation').value,
       tabRailWidth: this.readTabRailWidthSetting?.() ?? 256,
+      tabRailDetail: document.getElementById('appSettingsTabRailDetail').value,
       showTabDetachButton: document.getElementById('appSettingsShowTabDetachButton').checked,
       sessionListLayout: document.getElementById('appSettingsSessionListLayout').value,
       sessionSidebarFontSize: this.resolveSessionSidebarFontSize(
@@ -2443,6 +2453,7 @@ Object.assign(CodemanApp.prototype, {
         tabTwoRows: false,
         tabOrientation: 'horizontal',
         tabRailWidth: 256,
+        tabRailDetail: 'rich',
         sessionListLayout: 'header',
         sessionSidebarFontSize: 12,
         cjkInputEnabled: false,
@@ -2701,6 +2712,14 @@ Object.assign(CodemanApp.prototype, {
     const previous = root.getAttribute('data-tab-orientation') || 'horizontal';
     root.setAttribute('data-tab-orientation', orientation);
 
+    // Row detail rides on its OWN attribute, exactly like the sidebar's
+    // data-sidebar-detail: every html[data-tab-orientation='vertical'] rule in
+    // styles.css keeps matching both variants untouched, and the gate in app.js
+    // reads one attribute instead of re-parsing localStorage per tab.
+    const previousDetail = root.dataset.tabRailDetail || 'rich';
+    const detail = (settings.tabRailDetail ?? defaults.tabRailDetail ?? 'rich') === 'simple' ? 'simple' : 'rich';
+    root.dataset.tabRailDetail = detail;
+
     const tabsEl = document.getElementById('sessionTabs');
     const rail = document.getElementById('tabRail');
     const headerHost = document.getElementById('sessionTabsHost');
@@ -2718,13 +2737,43 @@ Object.assign(CodemanApp.prototype, {
     const settleRailWidth =
       options.settleRailWidth === true && (orientation === 'vertical' || previous !== orientation);
     this.applyTabRailWidth?.({ settle: settleRailWidth });
-    if (previous !== orientation) {
+    const orientationChanged = previous !== orientation;
+    // A detail flip counts as a change on its own: simple ⟷ detailed leaves the
+    // orientation on 'vertical' both times, and the stamps line is emitted by
+    // the row template, not toggled by CSS — same reasoning as the sidebar's
+    // detail half in applySessionListLayout(). Taller rows also move every
+    // connector anchored to a tab rect.
+    const changed = orientationChanged || previousDetail !== detail;
+    if (orientationChanged) {
       this.updateTabOverflowMode?.();
       if (!settleRailWidth) this.fitAddon?.fit();
-      this._fullRenderSessionTabs?.();
+    }
+    // applyTabWrapSettings() is the ONE owner of tabs-show-folder and is
+    // rail-aware, so it has to run AFTER the two attributes above — the
+    // applySessionListLayout() call that precedes this one on the settings-save
+    // path ran while data-tab-rail-detail still held the old value. It
+    // re-renders by itself when the folder row appears or disappears, which is
+    // why the render below is skipped in that case rather than doubled.
+    const prevTall = this._tallTabsEnabled;
+    if (changed) this.applyTabWrapSettings?.();
+    if (changed) {
+      // Mirror of applyTabWrapSettings()'s OWN render condition, which is
+      // `prevTallTabs !== undefined && prevTallTabs !== showFolder`: its first
+      // call ever only establishes the baseline and deliberately renders
+      // nothing. Reading an undefined previous value as "it rendered" skips
+      // BOTH renders and leaves the rows stale — reachable whenever this is the
+      // first call, i.e. when the pre-paint script threw and left the
+      // attributes on their fallbacks for applyTabOrientation() to correct.
+      const wrapRendered = prevTall !== undefined && prevTall !== this._tallTabsEnabled;
+      if (!wrapRendered) this._fullRenderSessionTabs?.();
       this._updateConnectionLinesImmediate?.();
       this._refreshHomeSessionsIfVisible?.();
     }
+    // Only detailed rows carry stamps that go stale with no event behind them.
+    // _fullRenderSessionTabs() settles this too, but applyTabOrientation() runs
+    // on paths where nothing re-rendered (boot with the layout already applied).
+    if (this.isRichTabRows?.()) this._startSidebarRichClock?.();
+    else this._stopSidebarRichClock?.();
   },
 
   applyTabWrapSettings() {
@@ -2746,7 +2795,13 @@ Object.assign(CodemanApp.prototype, {
     const twoRows = !sidebar && deviceType === 'desktop'
       ? (settings.tabTwoRows ?? defaults.tabTwoRows ?? false)
       : false;
-    const showFolder = sidebar || twoRows;
+    // The DETAILED vertical rail is the third tall-row surface, for the same
+    // reason as the sidebar: it is a docked column with a row per session, and
+    // the stamps line below the name says nothing about WHICH project the
+    // session is in. Read from the applied attribute, which applyTabOrientation()
+    // has already written (app.js calls it before this).
+    const railRich = this.isTabRailRich?.() === true;
+    const showFolder = sidebar || twoRows || railRich;
     const prevTallTabs = this._tallTabsEnabled;
     this._tallTabsEnabled = showFolder;
     const tabsEl = document.getElementById('sessionTabs');
@@ -2960,7 +3015,7 @@ Object.assign(CodemanApp.prototype, {
           'showFontControls', 'showSystemStats', 'showTokenCount', 'showCost',
           'showLifecycleLog', 'showResponseViewer', 'showRedrawButton',
           'showMonitor', 'showProjectInsights', 'showFileBrowser', 'showSubagents',
-          'subagentActiveTabOnly', 'tabTwoRows', 'tabOrientation', 'tabRailWidth', 'sessionListLayout', 'sessionSidebarFontSize', 'localEchoEnabled', 'cjkInputEnabled', 'extendedKeyboardBar',
+          'subagentActiveTabOnly', 'tabTwoRows', 'tabOrientation', 'tabRailWidth', 'tabRailDetail', 'sessionListLayout', 'sessionSidebarFontSize', 'localEchoEnabled', 'cjkInputEnabled', 'extendedKeyboardBar',
           'skin', 'showPlanUsageLimits', 'showAttachmentsButton', 'showFileViewerButton', 'webglRendererEnabled',
           'terminalFontFamily',
           'language',
diff --git a/src/web/public/styles.css b/src/web/public/styles.css
index 7533ea50f..e4ebf4e77 100644
--- a/src/web/public/styles.css
+++ b/src/web/public/styles.css
@@ -17217,19 +17217,31 @@ html[data-session-list="sidebar"] .session-tab.tab-filtered-out {
   display: none !important;
 }
 
-/* --- Rich rows (sessionListLayout 'sidebar-rich') ----------------------- */
+/* --- Rich rows (sessionListLayout 'sidebar-rich' + tabRailDetail 'rich') --- */
 /* The detailed variant of the SAME sidebar: identical column, identical
    re-parented #sessionTabs, identical filter and Alt+B toggle. The only
    difference is that each row also carries the line the desktop home rail and
    the phone overview carry — when the session was first created, how long it
    has been in the state it is in, and a status pill.
 
-   Everything here is scoped to html[data-sidebar-detail="rich"], which
+   The VERTICAL TAB RAIL is the second surface that draws those rows (it is a
+   docked column too, and #sessionTabs is the same element re-parented into it),
+   so every rule below carries a rail twin as an extra COMMA-GROUPED selector.
+   Deliberately not :is(): an :is() list takes its most specific argument's
+   specificity, which would silently raise the sidebar arm from (0,3,1) to the
+   rail arm's (0,5,1) and let these paint rules outrank things they never used
+   to. Grouped selectors each keep their own weight.
+
+   Sidebar rules are scoped to html[data-sidebar-detail="rich"], which
    applySessionListLayout() only ever sets to 'rich' while data-session-list is
-   'sidebar'. `.tab-meta` is emitted by the row template exclusively in that
-   mode, so these rules have nothing to match anywhere else — the display:none
-   below is the second lock, not the mechanism. */
-html[data-sidebar-detail="rich"] .session-sidebar .tab-meta {
+   'sidebar'; rail rules to html[data-tab-orientation='vertical']
+   [data-tab-rail-detail='rich']:not(.tab-rail-compact), so a rail dragged below
+   240px drops back to simple rows the same way the collapsed sidebar does.
+   `.tab-meta` is emitted by the row template exclusively in those modes, so
+   these rules have nothing to match anywhere else — the display:none below is
+   the second lock, not the mechanism. */
+html[data-sidebar-detail="rich"] .session-sidebar .tab-meta,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-meta {
   display: flex;
   align-items: center;
   gap: 0.35em;
@@ -17251,33 +17263,56 @@ html[data-sidebar-detail="rich"] .session-sidebar .tab-meta {
   display: none;
 }
 
-html[data-sidebar-detail="rich"] .session-sidebar .tab-meta-item {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-meta-item,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-meta-item {
   min-width: 0;
   overflow: hidden;
   text-overflow: ellipsis;
 }
 
-html[data-sidebar-detail="rich"] .session-sidebar .tab-meta-key {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-meta-key,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-meta-key {
   margin-right: 0.35em;
   opacity: 0.7;
   text-transform: uppercase;
   letter-spacing: 0.06em;
 }
 
-html[data-sidebar-detail="rich"] .session-sidebar .tab-meta-sep {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-meta-sep,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-meta-sep {
   opacity: 0.45;
 }
 
+/* Narrower than the detailed default (the .tab-rail-tight class,
+   _setTabRailWidth): the created stamp is dropped rather than shown as
+   "CREA…". Its value stays reachable as the tooltip on the meta LINE
+   (`.tab-meta` carries both absolute stamps, _sidebarRichMetaHTML) — the title
+   on the hidden `.tab-meta-created` itself goes away with it, since a
+   `display: none` element has no hover target. */
+html.tab-rail-tight[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-meta-created,
+html.tab-rail-tight[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-meta-sep {
+  display: none;
+}
+
+/* On a rail narrower than the detailed default, the state duration is the last
+   thing that should go: it is the number the row is sorted by, and the pill
+   next to it is only a word. The created stamp ellipsizes instead. */
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-meta-since {
+  flex-shrink: 0;
+}
+
 /* While a session is actually doing something, how long it has been doing it is
    what the eye should land on — same emphasis the home rail gives it. */
-html[data-sidebar-detail="rich"] .session-sidebar .session-tab.tab-state-working .tab-meta-since {
+html[data-sidebar-detail="rich"] .session-sidebar .session-tab.tab-state-working .tab-meta-since,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .session-tab.tab-state-working .tab-meta-since {
   color: var(--green);
   opacity: 0.95;
 }
 
 /* Pushed hard right and never shrinking, so the stamps ellipsize before the
    status word does. */
-html[data-sidebar-detail="rich"] .session-sidebar .tab-pill {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-pill,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-pill {
   flex-shrink: 0;
   margin-left: auto;
   padding: 0.1em 0.5em;
@@ -17294,19 +17329,23 @@ html[data-sidebar-detail="rich"] .session-sidebar .tab-pill {
 /* Same three colors as every other session surface: red means a question is
    pending, yellow means it wants input, green means work is happening. */
 html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--needs,
-html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--error {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--error,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-pill--needs,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-pill--error {
   background: color-mix(in srgb, var(--red) 18%, transparent);
   border-color: color-mix(in srgb, var(--red) 45%, transparent);
   color: var(--red);
 }
 
-html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--waiting {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--waiting,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-pill--waiting {
   background: color-mix(in srgb, var(--yellow) 18%, transparent);
   border-color: color-mix(in srgb, var(--yellow) 45%, transparent);
   color: var(--yellow);
 }
 
-html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--working {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--working,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-pill--working {
   background: color-mix(in srgb, var(--green) 15%, transparent);
   border-color: color-mix(in srgb, var(--green) 40%, transparent);
   color: var(--green);
@@ -17314,7 +17353,8 @@ html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--working {
 
 /* Muted one step further than the idle dot: the pill is a block of color, so it
    reads louder than a 9px dot at the same mix. */
-html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--idle {
+html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--idle,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .tab-pill--idle {
   background: color-mix(in srgb, var(--green) 7%, transparent);
   border-color: color-mix(in srgb, var(--green) 18%, var(--border));
   color: color-mix(in srgb, var(--green) 45%, var(--text-muted));
@@ -17329,7 +17369,8 @@ html[data-sidebar-detail="rich"] .session-sidebar .tab-pill--idle {
    then just a status dot and its badges. Without the guard, `align-items:
    flex-start` and a 0.15rem top margin on .tab-status would push that dot off
    the centre line of every row in the rail. */
-html[data-sidebar-detail="rich"]:not([data-sidebar="collapsed"]) .session-sidebar .session-tab {
+html[data-sidebar-detail="rich"]:not([data-sidebar="collapsed"]) .session-sidebar .session-tab,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .session-tab {
   align-items: flex-start;
   padding: 0.45rem 0.5rem;
 }
@@ -17338,7 +17379,10 @@ html[data-sidebar-detail="rich"]:not([data-sidebar="collapsed"]) .session-sideba
    three-line one it drifts low, so pin it to the name it acts on. */
 html[data-sidebar-detail="rich"]:not([data-sidebar="collapsed"]) .session-sidebar .session-tab .tab-actions,
 html[data-sidebar-detail="rich"]:not([data-sidebar="collapsed"]) .session-sidebar .session-tab .tab-number,
-html[data-sidebar-detail="rich"]:not([data-sidebar="collapsed"]) .session-sidebar .session-tab .tab-status {
+html[data-sidebar-detail="rich"]:not([data-sidebar="collapsed"]) .session-sidebar .session-tab .tab-status,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .session-tab .tab-name-row > .tab-actions,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .session-tab .tab-number,
+html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail .session-tab .tab-status {
   margin-top: 0.15rem;
 }
 
diff --git a/src/web/public/tab-rail-resize.js b/src/web/public/tab-rail-resize.js
index 6e1453185..ab2e54aba 100644
--- a/src/web/public/tab-rail-resize.js
+++ b/src/web/public/tab-rail-resize.js
@@ -70,7 +70,27 @@ Object.assign(CodemanApp.prototype, {
     const wasCompact = root.classList.contains('tab-rail-compact');
     const compact = resolved < 240;
     root.classList.toggle('tab-rail-compact', compact);
-    if (wasCompact !== compact) this._fullRenderSessionTabs?.();
+    // Second, softer threshold, CSS-only: a detailed row carries two stamps and
+    // below ~288px the created one ellipsizes to "CREA…", which says nothing.
+    // It is dropped there instead, leaving the state duration (the number the
+    // list is ordered by) and its pill intact. No re-render — unlike the rows
+    // themselves, this is a display toggle on markup that is already there.
+    root.classList.toggle('tab-rail-tight', resolved < 288);
+    if (wasCompact !== compact) {
+      // The folder line is owned by applyTabWrapSettings(), whose railRich
+      // input reads the compact class this function just toggled — without
+      // re-running it, a rich rail dragged below 240px kept emitting folder
+      // rows (and, for a stored width < 240, kept them across reloads: the
+      // boot-time wrap pass runs before this function first applies the
+      // class). It re-renders only when the folder flag actually flipped, so
+      // cover the flip-without-folder-change case (a simple-detail rail
+      // crossing 240px still changes the row-action affordance) without
+      // rendering twice.
+      const prevTall = this._tallTabsEnabled;
+      this.applyTabWrapSettings?.();
+      const wrapRendered = prevTall !== undefined && this._tallTabsEnabled !== prevTall;
+      if (!wrapRendered) this._fullRenderSessionTabs?.();
+    }
     const handle = document.getElementById('tabRailResizeHandle');
     if (handle) {
       handle.setAttribute('aria-valuemax', String(effectiveMax));
@@ -144,9 +164,28 @@ Object.assign(CodemanApp.prototype, {
     }, 150);
   },
 
+  /**
+   * The width a rail gets when the user has never picked one.
+   *
+   * Detailed rows carry a third line ("created 3d ago · working 12m" plus a
+   * status pill) and at 256px that line ellipsizes before it is finished — the
+   * same reason the rich SIDEBAR is 300px and the simple one 260px. 320px is
+   * the existing Wide preset, so a fresh detailed rail lands on a named choice
+   * rather than reading "Custom" in the settings select.
+   *
+   * Only the DEFAULT moves: a width the user has actually chosen (stored) is
+   * never overridden, and dragging the rail narrower is never fought — below
+   * 240px the rows drop back to simple ones on their own.
+   */
+  _defaultTabRailWidth() {
+    const rich = document.documentElement.dataset.tabRailDetail !== 'simple';
+    if (rich) return window.CodemanTabRail?.RICH_DEFAULT_WIDTH ?? 320;
+    return window.CodemanTabRail?.DEFAULT_WIDTH ?? 256;
+  },
+
   applyTabRailWidth(options = {}) {
     const settings = this.loadAppSettingsFromStorage();
-    const requested = settings.tabRailWidth ?? window.CodemanTabRail?.DEFAULT_WIDTH ?? 256;
+    const requested = settings.tabRailWidth ?? this._defaultTabRailWidth();
     const preferred = window.CodemanTabRail?.resolveWidth({ width: requested }) ?? 256;
     if (options.settle) this._claimTabRailResize();
     const resolved = this._setTabRailWidth(preferred);
@@ -198,6 +237,7 @@ Object.assign(CodemanApp.prototype, {
       key: event.key,
       shiftKey: event.shiftKey,
       currentWidth: this._getCurrentTabRailWidth(),
+      defaultWidth: this._defaultTabRailWidth?.(),
       ...this._getTabRailBounds(),
     });
     if (width === null || width === undefined) return;
@@ -240,7 +280,9 @@ Object.assign(CodemanApp.prototype, {
     handle.addEventListener('dblclick', (event) => {
       event.preventDefault();
       this._claimTabRailResize();
-      const preferred = window.CodemanTabRail?.DEFAULT_WIDTH || 256;
+      // Rich-aware: resetting a detailed rail to 256 would land it below the
+      // 288px tight threshold and silently drop the created stamp.
+      const preferred = this._defaultTabRailWidth?.() ?? (window.CodemanTabRail?.DEFAULT_WIDTH || 256);
       const effective = this._setTabRailWidth(preferred);
       this._scheduleTabRailSettle(effective, preferred);
     });
diff --git a/src/web/schemas.ts b/src/web/schemas.ts
index 3e09b01ab..4329dac39 100644
--- a/src/web/schemas.ts
+++ b/src/web/schemas.ts
@@ -997,6 +997,7 @@ export const SettingsUpdateSchema = z
     tabTwoRows: z.boolean().optional(),
     tabOrientation: z.enum(['horizontal', 'vertical']).optional(),
     tabRailWidth: z.number().int().min(208).max(360).optional(),
+    tabRailDetail: z.enum(['simple', 'rich']).optional(),
     /**
      * Session list layout. Display key (per-device).
      * 'header'       = horizontal tab strip
diff --git a/test/inline-rename.test.ts b/test/inline-rename.test.ts
index b89b1aa8b..d536917fa 100644
--- a/test/inline-rename.test.ts
+++ b/test/inline-rename.test.ts
@@ -125,6 +125,45 @@ describe('Inline rename input', () => {
     expect(renameStillActive).toBe(true);
   });
 
+  it('Escape cancels the rename instead of committing an empty name', async () => {
+    await resetState();
+    expect(await startRename('esc-cancel', 'rail-beta')).toBe(true);
+
+    // Escape used to clear the field and blur, and the blur handler commits —
+    // so cancelling a rename PUT an empty name, and the tab fell back to its
+    // folder label (measured against a live server, in the header strip as well
+    // as both vertical layouts). The observable here is the REQUEST: this
+    // harness's server has no such session, so a failed PUT would leave the
+    // local map looking innocent.
+    const result = await page.evaluate(async () => {
+      const app = (window as unknown as { app: { _activeRename: unknown } }).app;
+      const calls: string[] = [];
+      const origFetch = window.fetch;
+      window.fetch = (async (input: RequestInfo | URL) => {
+        calls.push(String(input));
+        return new Response('{"success":true}', { status: 200 });
+      }) as typeof window.fetch;
+
+      const inputEl = document.querySelector('input.tab-rename-input') as HTMLInputElement;
+      inputEl.value = 'typed-but-abandoned';
+      inputEl.dispatchEvent(new KeyboardEvent('keydown', { key: 'Escape', bubbles: true }));
+      // The blur that follows the input's removal must not resurrect the commit.
+      inputEl.dispatchEvent(new Event('blur'));
+      await new Promise((r) => setTimeout(r, 50));
+
+      window.fetch = origFetch;
+      return {
+        renamePuts: calls.filter((url) => url.includes('/api/sessions/esc-cancel/name')),
+        renameActive: !!app._activeRename,
+        inputStillInDom: document.body.contains(inputEl),
+      };
+    });
+
+    expect(result.renamePuts).toEqual([]);
+    expect(result.renameActive).toBe(false);
+    expect(result.inputStillInDom).toBe(false);
+  });
+
   it('CJK guard: regular Enter (no IME) DOES commit', async () => {
     await resetState();
     expect(await startRename('regular-enter', 'OldName')).toBe(true);
diff --git a/test/session-list-layout.test.ts b/test/session-list-layout.test.ts
index e27b803b2..44898db51 100644
--- a/test/session-list-layout.test.ts
+++ b/test/session-list-layout.test.ts
@@ -54,6 +54,8 @@ interface LayoutApp {
   _fullRenderSessionTabs(): void;
   updateConnectionLines(): void;
   isSessionSidebarRich(): boolean;
+  isTabRailRich(): boolean;
+  isRichTabRows(): boolean;
   _sidebarRichRow(id: string, session: Record<string, unknown>): RichRow | null;
   _sidebarRichMetaHTML(row: RichRow | null): string;
   _updateSidebarRichRow(tab: Element, id: string, session: Record<string, unknown>): void;
@@ -709,6 +711,22 @@ describe('rich session sidebar', () => {
     expect(html).toContain('data-i18n-skip');
   });
 
+  it('carries both absolute stamps on the LINE, not only on the two items', () => {
+    // Below 288px the rail hides `.tab-meta-created` (tab-rail-tight), and a
+    // title on a `display: none` element has no hover target — so a tooltip
+    // living only there means the created stamp is gone, not shrunk. The line
+    // itself has to carry it for the CSS rule's "still reachable" to be true.
+    const { app } = boot({ stored: { sessionListLayout: 'sidebar-rich' } });
+    stubOverview(app);
+    const html = app._sidebarRichMetaHTML(app._sidebarRichRow('s1', SESSION));
+
+    const line = html.slice(0, html.indexOf('>'));
+    expect(line).toContain('class="tab-meta"');
+    expect(line).toContain('title="');
+    expect(line).toContain('First created');
+    expect(line).toContain('working');
+  });
+
   it('drops the second stamp when the session has never been active', () => {
     const { app } = boot({ stored: { sessionListLayout: 'sidebar-rich' } });
     stubOverview(app);
@@ -795,7 +813,7 @@ describe('rich session sidebar', () => {
     // .tab-info is already a flex column, so the line needs no row-level
     // wrapping — and the collapsed 44px rail hides .tab-info wholesale, which is
     // what keeps the stamps out of it for free.
-    expect(APP).toContain('const richRows = this.isSessionSidebarRich();');
+    expect(APP).toContain('const richRows = this.isRichTabRows();');
     expect(APP).toContain('const richMeta = this._sidebarRichMetaHTML(richRow);');
     expect(APP).toContain('${richMeta}\n          </span>');
   });
@@ -819,3 +837,150 @@ describe('rich session sidebar', () => {
     expect(MOBILE_CSS).toContain('html[data-session-list="sidebar"][data-sidebar-detail="rich"] .session-sidebar {');
   });
 });
+
+describe('detailed rows in the vertical tab rail', () => {
+  /**
+   * The rail is the SECOND surface that draws rich rows. Everything about the
+   * row itself (model, markup, clock) is shared with the sidebar and covered
+   * above; what is new here is only the gate — which attribute turns it on,
+   * and the three ways it must turn back off.
+   */
+  const railBoot = (stored: Record<string, unknown>) => {
+    const booted = boot({ stored: { sessionListLayout: 'header', ...stored } });
+    booted.app.applySessionListLayout();
+    booted.app.applyTabOrientation();
+    return booted;
+  };
+
+  it('defaults the rail to detailed rows, since a docked column is not a tab strip', () => {
+    const { win, app } = railBoot({ tabOrientation: 'vertical' });
+    expect(win.document.documentElement.dataset.tabOrientation).toBe('vertical');
+    expect(win.document.documentElement.dataset.tabRailDetail).toBe('rich');
+    expect(app.isTabRailRich()).toBe(true);
+    expect(app.isRichTabRows()).toBe(true);
+    // The stamps go stale with no event behind them, so the clock has to run.
+    expect(app._sidebarRichClock).toBeTruthy();
+  });
+
+  it("honors the 'simple' opt-out", () => {
+    const { win, app } = railBoot({ tabOrientation: 'vertical', tabRailDetail: 'simple' });
+    expect(win.document.documentElement.dataset.tabRailDetail).toBe('simple');
+    expect(app.isTabRailRich()).toBe(false);
+    expect(app.isRichTabRows()).toBe(false);
+    // Falsy rather than null: _stopSidebarRichClock() returns early when there
+    // is no interval to clear, which is the state a rail that never armed one is in.
+    expect(app._sidebarRichClock).toBeFalsy();
+  });
+
+  it('drops back to simple rows once the rail is dragged into compact width', () => {
+    // Below 240px the rail already hides the row actions; three lines of stamps
+    // in a ~208px column ellipsize into noise. _setTabRailWidth() re-renders
+    // whenever this class flips, so the gate is re-read at the right moment.
+    const { win, app } = railBoot({ tabOrientation: 'vertical' });
+    expect(app.isTabRailRich()).toBe(true);
+    win.document.documentElement.classList.add('tab-rail-compact');
+    expect(app.isTabRailRich()).toBe(false);
+    expect(app.isRichTabRows()).toBe(false);
+  });
+
+  it('never draws stamps in the horizontal header strip', () => {
+    // tabRailDetail stays 'rich' in storage while the orientation is horizontal:
+    // the gate has to read BOTH, or the header strip inherits a meta line that
+    // has nowhere to go.
+    const { win, app } = railBoot({ tabOrientation: 'horizontal', tabRailDetail: 'rich' });
+    expect(win.document.documentElement.dataset.tabRailDetail).toBe('rich');
+    expect(app.isTabRailRich()).toBe(false);
+    expect(app.isRichTabRows()).toBe(false);
+  });
+
+  it('leaves the simple sidebar simple even with the rail set to detailed', () => {
+    // The sidebar owns the tabs whenever it is active, which forces the
+    // orientation back to horizontal — so a rail preference must not leak a
+    // meta line into a list the user asked to keep compact.
+    const { app } = railBoot({ sessionListLayout: 'sidebar', tabOrientation: 'vertical', tabRailDetail: 'rich' });
+    expect(app.isSessionSidebarActive()).toBe(true);
+    expect(app.isSessionSidebarRich()).toBe(false);
+    expect(app.isTabRailRich()).toBe(false);
+    expect(app.isRichTabRows()).toBe(false);
+  });
+
+  it('re-renders when only the DETAIL changes, orientation untouched', () => {
+    const { win, app } = railBoot({ tabOrientation: 'vertical', tabRailDetail: 'simple' });
+    (app._fullRenderSessionTabs as unknown as { mockClear(): void }).mockClear();
+
+    win.localStorage.setItem(
+      'codeman-app-settings',
+      JSON.stringify({ sessionListLayout: 'header', tabOrientation: 'vertical', tabRailDetail: 'rich' })
+    );
+    delete (app as unknown as { _cachedAppSettings?: unknown })._cachedAppSettings;
+    app.applyTabOrientation();
+
+    // The stamps line is emitted by the row template, not toggled by CSS: a
+    // missed render here means the setting repaints nothing until the next tick.
+    expect(win.document.documentElement.dataset.tabRailDetail).toBe('rich');
+    expect(app._fullRenderSessionTabs).toHaveBeenCalled();
+    expect(app._sidebarRichClock).toBeTruthy();
+  });
+
+  it('still renders on the first call, when applyTabWrapSettings only sets its baseline', () => {
+    // The pre-paint script stamps the layout attributes; if it THREW it leaves
+    // them on the catch-branch fallbacks and applyTabOrientation() is the first
+    // thing to correct them, with `_tallTabsEnabled` still undefined.
+    // applyTabWrapSettings() renders only when it has a previous value to
+    // compare, so reading "the value changed" as "it rendered" skipped BOTH
+    // renders and left the rows stale.
+    const { win, app } = boot({ stored: { sessionListLayout: 'header', tabOrientation: 'vertical' } });
+    expect(app._tallTabsEnabled).toBeUndefined();
+    expect(win.document.documentElement.getAttribute('data-tab-orientation')).toBeNull();
+
+    app.applyTabOrientation();
+
+    expect(win.document.documentElement.dataset.tabOrientation).toBe('vertical');
+    // The folder row turned on in the same pass, so this is exactly the case
+    // where the two guards could point at each other and neither fires.
+    expect(app._tallTabsEnabled).toBe(true);
+    expect(app._fullRenderSessionTabs).toHaveBeenCalled();
+  });
+
+  it('does not render twice when applyTabWrapSettings already did', () => {
+    // The mirror case: a detail flip that turns the folder row off makes
+    // applyTabWrapSettings() re-render, and applyTabOrientation() must not
+    // stack a second full rebuild of the strip on top of it.
+    const { win, app } = railBoot({ tabOrientation: 'vertical', tabRailDetail: 'rich' });
+    expect(app._tallTabsEnabled).toBe(true);
+    (app._fullRenderSessionTabs as unknown as { mockClear(): void }).mockClear();
+
+    win.localStorage.setItem(
+      'codeman-app-settings',
+      JSON.stringify({ sessionListLayout: 'header', tabOrientation: 'vertical', tabRailDetail: 'simple' })
+    );
+    delete (app as unknown as { _cachedAppSettings?: unknown })._cachedAppSettings;
+    app.applyTabOrientation();
+
+    expect(app._tallTabsEnabled).toBe(false);
+    expect(app._fullRenderSessionTabs).toHaveBeenCalledTimes(1);
+  });
+
+  it('plumbs the rail detail through the settings UI, the schema and the pre-paint script', () => {
+    expect(INDEX_HTML).toContain('id="appSettingsTabRailDetail"');
+    expect(INDEX_HTML).toContain('<option value="rich">Detailed</option>');
+    // Pre-paint stamps it with the rest of the layout keys, or a detailed rail
+    // paints as a simple one for the first frame and then jumps a row taller.
+    expect(INDEX_HTML).toContain("dataset.tabRailDetail=(A.tabRailDetail==='simple')?'simple':'rich'");
+    expect(SETTINGS_UI).toContain("document.getElementById('appSettingsTabRailDetail').value");
+    const displayKeys = SETTINGS_UI.slice(SETTINGS_UI.indexOf('const displayKeys = new Set(['));
+    expect(displayKeys.slice(0, 1800)).toContain("'tabRailDetail'");
+    expect(SCHEMAS).toMatch(/tabRailDetail:\s*z\.enum\(\['simple',\s*'rich'\]\)\.optional\(\)/);
+  });
+
+  it('gives every rich paint rule a rail twin without raising the sidebar arm', () => {
+    // Comma-grouped, never :is() — an :is() list takes its most specific
+    // argument, which would lift the sidebar selectors from (0,3,1) to the
+    // rail's (0,5,1) and let them outrank rules they never used to.
+    const rail = "html[data-tab-orientation='vertical'][data-tab-rail-detail='rich']:not(.tab-rail-compact) .tab-rail";
+    for (const suffix of ['.tab-meta', '.tab-meta-key', '.tab-pill', '.tab-pill--working']) {
+      expect(STYLES_CSS).toContain(`${rail} ${suffix}`);
+    }
+    expect(STYLES_CSS).not.toContain(':is(html[data-sidebar-detail="rich"]');
+  });
+});
diff --git a/test/tab-rail-resize.test.ts b/test/tab-rail-resize.test.ts
index 365124d7d..8d5a3c364 100644
--- a/test/tab-rail-resize.test.ts
+++ b/test/tab-rail-resize.test.ts
@@ -53,6 +53,10 @@ describe('tab rail width policy', () => {
     expect(policy.resolveKeyboardWidth({ ...base, key: 'Home' })).toBe(208);
     expect(policy.resolveKeyboardWidth({ ...base, key: 'End' })).toBe(360);
     expect(policy.resolveKeyboardWidth({ ...base, key: 'Enter' })).toBe(256);
+    // Enter resets to the CALLER's effective default: a rich rail passes 320
+    // (its unsized rendering width), so the reset cannot land it below the
+    // 288px tight threshold the way a hardcoded 256 did.
+    expect(policy.resolveKeyboardWidth({ ...base, key: 'Enter', defaultWidth: 320 })).toBe(320);
     expect(policy.resolveKeyboardWidth({ ...base, key: 'Escape' })).toBeNull();
   });
 });
@@ -123,6 +127,61 @@ describe('tab rail resize wiring', () => {
     expect(app._tabRailResizeOwnsObserver).toBe(false);
   });
 
+  it('re-runs the wrap pass when the compact threshold flips, without double-rendering', () => {
+    const controller = readPublic('tab-rail-resize.js');
+    class FakeCodemanApp {}
+    const classes = new Set<string>();
+    const context = vm.createContext({
+      CodemanApp: FakeCodemanApp,
+      window: { CodemanTabRail: loadRailPolicy() },
+      document: {
+        documentElement: {
+          style: { setProperty: () => {} },
+          classList: {
+            contains: (c: string) => classes.has(c),
+            toggle: (c: string, force: boolean) => {
+              if (force) classes.add(c);
+              else classes.delete(c);
+              return force;
+            },
+          },
+        },
+        getElementById: () => null,
+        querySelector: () => null,
+      },
+      console,
+      clearTimeout,
+      setTimeout,
+    });
+    vm.runInContext(controller, context, { filename: 'tab-rail-resize.js' });
+    const app = new FakeCodemanApp() as FakeCodemanApp & Record<string, any>;
+    app._getTabRailBounds = () => ({});
+    app.syncTabRailWidthSetting = vi.fn();
+    app._fullRenderSessionTabs = vi.fn();
+
+    // Rich rail dragged below 240px: applyTabWrapSettings() owns the folder
+    // line and reads the compact class this call just toggled, so it must be
+    // re-consulted on the flip — and when its own conditional render fires
+    // (the folder flag changed), the explicit render must not double it.
+    app._tallTabsEnabled = true;
+    app.applyTabWrapSettings = vi.fn(() => {
+      app._tallTabsEnabled = false;
+      app._fullRenderSessionTabs();
+    });
+    app._setTabRailWidth(210);
+    expect(app.applyTabWrapSettings).toHaveBeenCalledOnce();
+    expect(app._fullRenderSessionTabs).toHaveBeenCalledOnce();
+
+    // Flip back up with an unchanged folder flag (simple-detail rail): the
+    // explicit render must still fire — the compact row-action affordance
+    // changed even though the wrap pass rendered nothing.
+    app.applyTabWrapSettings = vi.fn();
+    app._fullRenderSessionTabs = vi.fn();
+    app._setTabRailWidth(300);
+    expect(app.applyTabWrapSettings).toHaveBeenCalledOnce();
+    expect(app._fullRenderSessionTabs).toHaveBeenCalledOnce();
+  });
+
   it('keeps resize-observer ownership for pointer drags longer than the watchdog', async () => {
     vi.useFakeTimers();
     const controller = readPublic('tab-rail-resize.js');