feat(maestro): drill into a session's action page with tab

Tab on a highlighted session in the web command bar opens that session's
action page in the same overlay: kill, rename, spawn similar, still fuzzy
searchable and headed by the session's name. Escape, or backspace at an
empty query, returns to the result list with the previous query intact.

Each action raises the flow the card already has. The two that lived
inside the sidebar get an event apiece — the confirm-and-blockers kill and
the inline rename prompt — so the bar picks the action and nothing more;
spawn similar reuses the existing SPAWN_SIMILAR_EVENT.

web/src/barActions.test.ts

@@ -0,0 +1,131 @@
+// @vitest-environment happy-dom
+//
+// The sidebar's half of the command bar's action page (#151): the bar picks
+// kill or rename and raises the flow the card already has, so what the page
+// runs is what the ✕ button and the `r` key run.
+import { afterEach, beforeAll, describe, expect, it } from "vitest";
+
+import { KILL_SESSION_EVENT, RENAME_SESSION_EVENT, renderSidebar } from "./catalog.js";
+import type { CatalogListener, CatalogStore } from "./events.js";
+import type { Session } from "./types.js";
+
+beforeAll(() => {
+  Object.defineProperty(window, "localStorage", {
+    value: { getItem: () => null, setItem: () => {} },
+  });
+});
+
+let mounted: { el: HTMLElement; dispose: () => void } | null = null;
+
+afterEach(() => {
+  document.querySelector(".kill-dialog")?.remove();
+  mounted?.dispose();
+  mounted = null;
+  document.body.replaceChildren();
+});
+
+function session(overrides: Partial<Session> = {}): Session {
+  return {
+    id: "aaaaaaaa-0000-0000-0000-0000000000ff",
+    cwd: "/home/naps/tea/maestro",
+    command: "claude",
+    env: {},
+    metadata: { name: "amber-falcon" },
+    status: "Running",
+    created_at: "2026-08-24T10:00:00Z",
+    ...overrides,
+  };
+}
+
+function storeWith(sessions: Session[]): CatalogStore {
+  const state = { sessions: new Map(sessions.map((s) => [s.id, s])) };
+  return {
+    snapshot: () => state,
+    subscribe: (fn: CatalogListener) => {
+      fn(state);
+      return () => {};
+    },
+  } as unknown as CatalogStore;
+}
+
+function mount(s: Session): HTMLElement {
+  const handle = renderSidebar(storeWith([s]));
+  mounted = handle;
+  document.body.appendChild(handle.el);
+  return handle.el;
+}
+
+function raise(name: string, s: Session): void {
+  document.dispatchEvent(new CustomEvent(name, { detail: s }));
+}
+
+/** Let the kill chain's awaits (fetch, its json body) settle. */
+async function flush(): Promise<void> {
+  for (let i = 0; i < 8; i++) await Promise.resolve();
+}
+
+describe("kill from the action page", () => {
+  it("goes through the daemon, without a first confirmation", async () => {
+    const calls: string[] = [];
+    window.fetch = ((url: string, init?: RequestInit) => {
+      calls.push(`${init?.method ?? "GET"} ${url}`);
+      return Promise.resolve(new Response(null, { status: 204 }));
+    }) as typeof fetch;
+    const s = session();
+    mount(s);
+    raise(KILL_SESSION_EVENT, s);
+    await flush();
+    expect(calls).toContain(`DELETE /api/sessions/${s.id}`);
+    expect(document.querySelector(".kill-dialog")).toBeNull();
+  });
+
+  it("raises the existing confirm-and-blockers dialog on a guarded refusal", async () => {
+    window.fetch = ((url: string) => {
+      if (String(url).includes("force=true")) {
+        return Promise.resolve(new Response(null, { status: 204 }));
+      }
+      return Promise.resolve(
+        new Response(
+          JSON.stringify({
+            error: {
+              code: "kill_guarded",
+              message: "worktree has unsaved work",
+              unsaved_work: { untracked_files: 1 },
+            },
+          }),
+          { status: 409, headers: { "content-type": "application/json" } },
+        ),
+      );
+    }) as typeof fetch;
+    const s = session({ blocked_work: { untracked_files: 1 } });
+    mount(s);
+    raise(KILL_SESSION_EVENT, s);
+    await flush();
+    const dialog = document.querySelector(".kill-dialog");
+    expect(dialog?.getAttribute("aria-label")).toBe("Kill amber-falcon");
+    expect(dialog?.textContent).toContain("1 untracked file");
+  });
+});
+
+describe("rename from the action page", () => {
+  it("expands the folder hiding the card, since the prompt lives in the card", () => {
+    window.fetch = (() => Promise.reject(new Error("offline"))) as typeof fetch;
+    const s = session();
+    const el = mount(s);
+    const folder = el.querySelector<HTMLElement>(".tree-folder-header");
+    folder?.click();
+    expect(el.querySelector(`[data-session-id="${s.id}"]`)).toBeNull();
+    raise(RENAME_SESSION_EVENT, s);
+    expect(el.querySelector<HTMLInputElement>(".leaf-rename")?.value).toBe("amber-falcon");
+  });
+
+  it("raises the card's own prompt, pre-filled with the session's name", () => {
+    window.fetch = (() => Promise.reject(new Error("offline"))) as typeof fetch;
+    const s = session();
+    const el = mount(s);
+    raise(RENAME_SESSION_EVENT, s);
+    const input = el.querySelector<HTMLInputElement>(".leaf-rename");
+    expect(input?.value).toBe("amber-falcon");
+    expect(input?.getAttribute("aria-label")).toBe("Rename amber-falcon");
+  });
+});

web/src/catalog.ts

@@ -7,6 +7,7 @@ import { CommandSet, defineCommands } from "./commands.js";
 import { CatalogStore } from "./events.js";
 import type { InTheWay, Session } from "./types.js";
 import {
+  abbreviateCwd,
   abbreviateFolderName,
   blockerStats,
   customSessionName,
@@ -16,6 +17,7 @@ import {
   sessionBlockers,
   isProvisionalName,
   sessionName,
+  sessionTreePath,
 } from "./types.js";
 import { splitCommand, toolIconSvg } from "./toolIcon.js";
 import {
@@ -50,6 +52,17 @@ export const FOCUS_SIDEBAR_EVENT = "catalog-focus-sidebar";
  *  ("Spawn similar"). Detail is the session being cloned. */
 export const SPAWN_SIMILAR_EVENT = "catalog-spawn-similar";
 
+/** Ask the sidebar to kill a session — the command bar's action page picking
+ *  `kill` (#151). Detail is the session. Handled here, so the kill goes
+ *  through the same confirm-and-blockers flow the card's ✕ does
+ *  (`docs/WORKTREES.md`); the bar never reimplements it. */
+export const KILL_SESSION_EVENT = "catalog-kill-session";
+
+/** Ask the sidebar to rename a session — the command bar's action page picking
+ *  `rename` (#151). Detail is the session. The prompt is the card's own inline
+ *  field, pre-filled with the session's name (`docs/SIDEBAR.md`). */
+export const RENAME_SESSION_EVENT = "catalog-rename-session";
+
 /** A session row was clicked (issue #133). The row's `href` drives normal
  *  hash navigation, but a split/drag can move focus without ever touching
  *  `location.hash` — so a click back onto a session whose hash still
@@ -745,6 +758,40 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
   };
   document.addEventListener("catalog-rerender", rerenderHandler);
 
+  // The command bar's action page (#151) picks an action and hands it here:
+  // both flows are the ones the card already has, reached by session rather
+  // than by row.
+  const killHandler = (ev: Event) => {
+    const s = (ev as CustomEvent<Session>).detail;
+    void requestKill(s, sessionName(s));
+  };
+  const renameHandler = (ev: Event) => {
+    const s = (ev as CustomEvent<Session>).detail;
+    const row = rowForSession(s);
+    if (row) beginRename(row, s);
+  };
+  document.addEventListener(KILL_SESSION_EVENT, killHandler);
+  document.addEventListener(RENAME_SESSION_EVENT, renameHandler);
+
+  /** The card a session is rendered as, expanding whatever folder hides it
+   *  first: the rename prompt lives inside the card, so a collapsed folder
+   *  would otherwise swallow the request. */
+  function rowForSession(s: Session): HTMLElement | null {
+    const find = () => treeHost.querySelector<HTMLElement>(`.tree-leaf[data-session-id="${s.id}"]`);
+    const found = find();
+    if (found) return found;
+    // Folder paths are the abbreviated directory's segments joined back up
+    // (see buildTree), so the session's own path is normalised the same way
+    // before it is compared against them.
+    const cwd = sessionTreePath(s);
+    const path = (cwd ? abbreviateCwd(cwd, homeDir) : "").split("/").filter(Boolean).join("/");
+    for (const folder of [...collapsed]) {
+      if (path === folder || path.startsWith(`${folder}/`)) collapsed.delete(folder);
+    }
+    rerenderHandler();
+    return find();
+  }
+
   // "Spawn similar" (#28) is dispatched here and handled in main.ts, where the
   // multi-view controller can seed the spawn modal with the session's dir/command.
 
@@ -794,6 +841,8 @@ export function renderSidebar(store: CatalogStore, opts: SidebarOptions = {}): S
       // refusing to refresh.
       renamingId = null;
       document.removeEventListener("catalog-rerender", rerenderHandler);
+      document.removeEventListener(KILL_SESSION_EVENT, killHandler);
+      document.removeEventListener(RENAME_SESSION_EVENT, renameHandler);
       unsubscribe();
     },
   };

web/src/commandBar.test.ts

@@ -1,7 +1,12 @@
 // @vitest-environment happy-dom
 import { afterEach, describe, expect, it, vi } from "vitest";
 
-import { SESSION_SELECT_EVENT } from "./catalog.js";
+import {
+  KILL_SESSION_EVENT,
+  RENAME_SESSION_EVENT,
+  SESSION_SELECT_EVENT,
+  SPAWN_SIMILAR_EVENT,
+} from "./catalog.js";
 import {
   barGroups,
   barRows,
@@ -15,6 +20,7 @@ import {
   orderSessionsForBar,
   parseBarQuery,
   sessionBarCandidates,
+  sessionActionCandidates,
   sessionCandidate,
   SPAWN_DIRECTORY_EVENT,
 } from "./commandBar.js";
@@ -542,3 +548,176 @@ describe("the focus round-trip over a pane (#152)", () => {
     }
   });
 });
+
+describe("the session action page (#151)", () => {
+  const sessions = [
+    session("api", {
+      metadata: { name: "api" },
+      current_cwd: "/home/me/dev/api",
+      last_focused_at: "2026-01-01T11:00:00Z",
+    }),
+    session("worker", {
+      metadata: { name: "worker" },
+      current_cwd: "/home/me/dev/worker",
+      last_focused_at: "2026-01-01T10:00:00Z",
+    }),
+  ];
+
+  function open(over: Partial<Parameters<typeof openCommandBar>[0]> = {}) {
+    return openCommandBar({
+      sessions,
+      homeDir: "/home/me",
+      commands: [],
+      onOpenSession: () => {},
+      ...over,
+    });
+  }
+
+  function headerText(): string | undefined {
+    return document.querySelector(".cmdbar-page-header")?.textContent ?? undefined;
+  }
+
+  it("lists kill, rename and spawn similar for the highlighted session", () => {
+    open();
+    press("Tab");
+    expect(rowNames()).toEqual(["Kill session", "Rename session", "Spawn similar"]);
+    expect(activeName()).toBe("Kill session");
+  });
+
+  it("names the session being acted on", () => {
+    open();
+    press("ArrowDown");
+    press("Tab");
+    expect(headerText()).toContain("worker");
+  });
+
+  it("drops the kind headers, since the page is one kind", () => {
+    open();
+    press("Tab");
+    expect(document.querySelectorAll(".cmdbar-group-title")).toHaveLength(0);
+  });
+
+  it("stays fuzzy-searchable over the three actions", () => {
+    open();
+    press("Tab");
+    type("ren");
+    expect(rowNames()).toEqual(["Rename session"]);
+    type("spwn");
+    expect(rowNames()).toEqual(["Spawn similar"]);
+    type("zzz");
+    expect(document.querySelector(".cmdbar-empty")?.textContent).toBe("No matches");
+  });
+
+  it("does nothing on a command row", () => {
+    openCommandBar({
+      sessions,
+      homeDir: "/home/me",
+      commands: [{ ...COMMAND_SPECS[0], run: () => {} } as Command],
+      onOpenSession: () => {},
+    });
+    type(">");
+    const before = rowNames();
+    press("Tab");
+    expect(rowNames()).toEqual(before);
+    expect(headerText()).toBeUndefined();
+  });
+
+  it("does nothing on a directory row", async () => {
+    open({ loadDirectories: () => Promise.resolve(["/home/me/dev/api"]) });
+    type("~");
+    await Promise.resolve();
+    press("Tab");
+    expect(rowNames()).toEqual(["~/dev/api"]);
+    expect(headerText()).toBeUndefined();
+  });
+
+  it("returns to the result list on Escape, with the previous query intact", () => {
+    open();
+    type("wor");
+    press("Tab");
+    expect(headerText()).toContain("worker");
+    press("Escape");
+    expect(isCommandBarOpen()).toBe(true);
+    expect(headerText()).toBeUndefined();
+    expect((document.querySelector(".cmdbar-input") as HTMLInputElement).value).toBe("wor");
+    expect(rowNames()).toEqual(["worker"]);
+  });
+
+  it("returns to the result list on backspace at an empty query", () => {
+    open();
+    type("wor");
+    press("Tab");
+    type("");
+    press("Backspace");
+    expect(headerText()).toBeUndefined();
+    expect((document.querySelector(".cmdbar-input") as HTMLInputElement).value).toBe("wor");
+    expect(rowNames()).toEqual(["worker"]);
+  });
+
+  it("keeps backspace ordinary while the page's query has text", () => {
+    open();
+    press("Tab");
+    type("ren");
+    press("Backspace");
+    expect(headerText()).toContain("api");
+    expect(rowNames()).toEqual(["Rename session"]);
+  });
+
+  it("closes the bar when the page's Escape has already been used", () => {
+    open();
+    press("Tab");
+    press("Escape");
+    press("Escape");
+    expect(isCommandBarOpen()).toBe(false);
+  });
+
+  it("raises kill, rename and spawn similar with the session, closing the bar", () => {
+    const seen: string[] = [];
+    for (const [hook, key] of [
+      ["onKillSession", "Kill session"],
+      ["onRenameSession", "Rename session"],
+      ["onSpawnSimilar", "Spawn similar"],
+    ] as const) {
+      open({ [hook]: (s: Session) => seen.push(`${hook}:${s.id}`) });
+      type("wor");
+      press("Tab");
+      type(key);
+      press("Enter");
+      expect(isCommandBarOpen()).toBe(false);
+    }
+    expect(seen).toEqual([
+      "onKillSession:worker",
+      "onRenameSession:worker",
+      "onSpawnSimilar:worker",
+    ]);
+  });
+
+  it("hands each action to the flow it already has, by default", () => {
+    const seen: string[] = [];
+    const listeners: Array<[string, EventListener]> = [
+      [KILL_SESSION_EVENT, (e) => seen.push(`kill:${(e as CustomEvent<Session>).detail.id}`)],
+      [RENAME_SESSION_EVENT, (e) => seen.push(`rename:${(e as CustomEvent<Session>).detail.id}`)],
+      [SPAWN_SIMILAR_EVENT, (e) => seen.push(`similar:${(e as CustomEvent<Session>).detail.id}`)],
+    ];
+    for (const [name, fn] of listeners) document.addEventListener(name, fn);
+    try {
+      for (const action of ["Kill session", "Rename session", "Spawn similar"]) {
+        open();
+        press("Tab");
+        type(action);
+        press("Enter");
+      }
+    } finally {
+      for (const [name, fn] of listeners) document.removeEventListener(name, fn);
+    }
+    expect(seen).toEqual(["kill:api", "rename:api", "similar:api"]);
+  });
+
+  it("offers no action beyond the three", () => {
+    expect(sessionActionCandidates().map((c) => c.action.id)).toEqual([
+      "kill",
+      "rename",
+      "spawn-similar",
+    ]);
+  });
+});

web/src/commandBar.ts

@@ -2,11 +2,16 @@
 // list, opened from the sidebar, closed with Escape.
 //
 // Three kinds live here: sessions and commands, ranked together by default,
-// and directories, which need the `~` sigil. The action page and the
-// terminal-focus binding land in #151-#152.
+// and directories, which need the `~` sigil. `tab` on a session drills into
+// its action page (#151), which is the same overlay over three actions.
 
 import { listDir, projects as fetchProjects, recentDirs } from "./api.js";
-import { SESSION_SELECT_EVENT } from "./catalog.js";
+import {
+  KILL_SESSION_EVENT,
+  RENAME_SESSION_EVENT,
+  SESSION_SELECT_EVENT,
+  SPAWN_SIMILAR_EVENT,
+} from "./catalog.js";
 import { keyCaps, publishedCommands, type Command } from "./commands.js";
 import {
   matchAndRank,
@@ -30,7 +35,13 @@ export type CommandBarCandidate = CommandCandidate & { command: Command };
  *  ranks; `path` is the one a spawn is made in. */
 export type DirectoryBarCandidate = DirectoryCandidate & { path: string };
 
-export type BarCandidate = SessionBarCandidate | CommandBarCandidate | DirectoryBarCandidate;
+/** One row of a session's action page. It is a `command` to the matcher — a
+ *  single `label` field, ranked exactly like a registry command — and carries
+ *  the action it stands for instead of a registry entry. */
+export type ActionBarCandidate = CommandCandidate & { action: SessionAction };
+
+export type BarCandidate =
+  SessionBarCandidate | CommandBarCandidate | ActionBarCandidate | DirectoryBarCandidate;
 export type BarResult = MatchResult<BarCandidate>;
 
 /** Raised when Enter lands on a directory row. The bar picks the directory; the
@@ -73,6 +84,40 @@ export function parseBarQuery(raw: string): BarQuery {
   return { sigil: null, query: raw };
 }
 
+// ---- the session action page ----
+
+/** The actions a session's action page offers, and no others: the bar picks
+ *  one and hands off to the flow that already implements it
+ *  (docs/COMMAND-BAR.md, "Drill-in"). */
+export type SessionActionId = "kill" | "rename" | "spawn-similar";
+
+export interface SessionAction {
+  id: SessionActionId;
+  label: string;
+}
+
+export const SESSION_ACTIONS: readonly SessionAction[] = [
+  { id: "kill", label: "Kill session" },
+  { id: "rename", label: "Rename session" },
+  { id: "spawn-similar", label: "Spawn similar" },
+];
+
+/** The action page's candidates, in the order above — which is the order an
+ *  empty query lists them in, since the matcher keeps input order. */
+export function sessionActionCandidates(): ActionBarCandidate[] {
+  return SESSION_ACTIONS.map((action) => ({
+    kind: "command",
+    action,
+    fields: { label: action.label },
+  }));
+}
+
+/** Narrow a `command` candidate to an action row. Both share the matcher's
+ *  `command` kind, so what separates them is what they carry. */
+export function isActionCandidate(candidate: BarCandidate): candidate is ActionBarCandidate {
+  return candidate.kind === "command" && "action" in candidate;
+}
+
 // ---- candidates ----
 
 function focusedAt(s: Session): number | null {
@@ -306,6 +351,8 @@ function renderRow(result: BarResult, index: number): HTMLElement {
   if (candidate.kind === "session") {
     row.dataset.sessionId = candidate.session.id;
     if (candidate.session.status === "Dead") row.classList.add("is-dead");
+  } else if (isActionCandidate(candidate)) {
+    row.dataset.actionId = candidate.action.id;
   } else if (candidate.kind === "command") {
     row.dataset.commandId = candidate.command.id;
   } else {
@@ -322,7 +369,7 @@ function renderRow(result: BarResult, index: number): HTMLElement {
 
   // The chord is teaching material, not a match target: it is rendered from
   // the live registry entry and never fed to the matcher.
-  if (candidate.kind === "command") {
+  if (candidate.kind === "command" && !isActionCandidate(candidate)) {
     const keys = document.createElement("span");
     keys.className = "cmdbar-row-keys";
     for (const cap of keyCaps(candidate.command.keys[0])) {
@@ -374,6 +421,13 @@ export interface CommandBarOptions {
    *  `SPAWN_DIRECTORY_EVENT`, which the shell turns into a fast-forward
    *  spawn. */
   onSpawnDirectory?: (path: string) => void;
+  /** The action page's three actions (#151). Each defaults to raising the
+   *  event the flow that already implements it listens on — the sidebar's
+   *  confirm-and-blockers kill, its inline rename prompt, the spawn form
+   *  seeded from the session. The bar picks the action and nothing more. */
+  onKillSession?: (session: Session) => void;
+  onRenameSession?: (session: Session) => void;
+  onSpawnSimilar?: (session: Session) => void;
 }
 
 interface OpenBar {
@@ -406,6 +460,14 @@ export function openCommandBar(opts: CommandBarOptions): HTMLElement {
     opts.onSpawnDirectory ??
     ((path: string) =>
       document.dispatchEvent(new CustomEvent(SPAWN_DIRECTORY_EVENT, { detail: path })));
+  const sessionEvent =
+    (name: string) =>
+    (session: Session): void => {
+      document.dispatchEvent(new CustomEvent(name, { detail: session }));
+    };
+  const killSession = opts.onKillSession ?? sessionEvent(KILL_SESSION_EVENT);
+  const renameSession = opts.onRenameSession ?? sessionEvent(RENAME_SESSION_EVENT);
+  const spawnSimilar = opts.onSpawnSimilar ?? sessionEvent(SPAWN_SIMILAR_EVENT);
   const loadDirectories = opts.loadDirectories ?? loadBarDirectories;
   const listEntries =
     opts.listDirEntries ?? ((dir: string) => listDir(dir).then((listing) => listing.entries));
@@ -450,6 +512,13 @@ export function openCommandBar(opts: CommandBarOptions): HTMLElement {
   let rows: BarResult[] = [];
   let highlighted = 0;
 
+  // The action page (#151). `page` is the session being acted on, `stashed`
+  // the result-list query it was drilled into from — backing out restores it,
+  // so the round trip costs the operator nothing.
+  let page: Session | null = null;
+  let stashed = "";
+  let header: HTMLElement | null = null;
+
   // `~`'s candidates: the recents-and-projects list, fetched once, plus
   // whatever `/api/dirs` has filled in for the directory being typed.
   let directories: DirectoryBarCandidate[] = [];
@@ -516,6 +585,7 @@ export function openCommandBar(opts: CommandBarOptions): HTMLElement {
    *  list is mixed — sessions and commands together — except on an empty query,
    *  where the bar is a session switcher. */
   function candidatesFor(parsed: BarQuery): BarCandidate[] {
+    if (page) return sessionActionCandidates();
     switch (parsed.sigil) {
       case ">":
         return [...commandCandidates];
@@ -547,9 +617,27 @@ export function openCommandBar(opts: CommandBarOptions): HTMLElement {
     if (rows.length === 0) input.removeAttribute("aria-activedescendant");
   }
 
+  /** The line naming the session being acted on, so the target is never
+   *  ambiguous. Present only while the action page is up. */
+  function paintHeader(): void {
+    header?.remove();
+    header = null;
+    if (!page) return;
+    header = document.createElement("div");
+    header.className = "cmdbar-page-header";
+    header.setAttribute("role", "presentation");
+    header.textContent = `Actions for "${sessionName(page)}"`;
+    panel.insertBefore(header, results);
+  }
+
   function render(): void {
-    const parsed = parseBarQuery(input.value);
-    input.placeholder = PLACEHOLDERS[parsed.sigil ?? "mixed"];
+    // On the action page the query line is over the three actions, so there is
+    // no sigil to read: `>` and `~` are ordinary characters there.
+    const parsed = page ? { sigil: null, query: input.value } : parseBarQuery(input.value);
+    input.placeholder = page
+      ? `Act on ${sessionName(page)}…`
+      : PLACEHOLDERS[parsed.sigil ?? "mixed"];
+    paintHeader();
     rows = barRows(parsed.query, candidatesFor(parsed));
     // The highlight starts on the globally best row every time the list
     // changes: an old index would point at a different result.
@@ -567,8 +655,9 @@ export function openCommandBar(opts: CommandBarOptions): HTMLElement {
 
     let index = 0;
     for (const group of barGroups(rows)) {
-      // While a sigil is in force there is one kind, so the header is dropped.
-      if (parsed.sigil === null) {
+      // While a sigil is in force there is one kind, so the header is
+      // dropped — and the action page is one kind too.
+      if (parsed.sigil === null && !page) {
         const header = document.createElement("div");
         header.className = "cmdbar-group-title";
         header.setAttribute("role", "presentation");
@@ -593,10 +682,50 @@ export function openCommandBar(opts: CommandBarOptions): HTMLElement {
     paintHighlight();
   }
 
+  /** `tab`: drill into the highlighted session's action page. No effect on any
+   *  other kind, and none on the page itself, which has no session rows. */
+  function drillIn(): void {
+    const candidate = rows[highlighted]?.candidate;
+    if (page || candidate?.kind !== "session") return;
+    page = candidate.session;
+    stashed = input.value;
+    input.value = "";
+    render();
+  }
+
+  /** Escape, or backspace at an empty query: back to the result list with the
+   *  query the drill-in was made from. */
+  function leavePage(): void {
+    page = null;
+    input.value = stashed;
+    stashed = "";
+    render();
+  }
+
+  function runAction(action: SessionAction, session: Session): void {
+    close();
+    switch (action.id) {
+      case "kill":
+        killSession(session);
+        return;
+      case "rename":
+        renameSession(session);
+        return;
+      case "spawn-similar":
+        spawnSimilar(session);
+        return;
+    }
+  }
+
   function activate(index: number): void {
     const result = rows[index];
     if (!result) return;
     const candidate = result.candidate;
+    if (isActionCandidate(candidate)) {
+      // The page cannot be up without a session to act on.
+      if (page) runAction(candidate.action, page);
+      return;
+    }
     close();
     switch (candidate.kind) {
       case "session":
@@ -615,7 +744,20 @@ export function openCommandBar(opts: CommandBarOptions): HTMLElement {
     switch (e.key) {
       case "Escape":
         e.preventDefault();
-        close();
+        // On an action page Escape is one level up, not the way out.
+        if (page) leavePage();
+        else close();
+        return;
+      case "Tab":
+        e.preventDefault();
+        drillIn();
+        return;
+      case "Backspace":
+        // Ordinary editing, except at an empty query on the action page.
+        if (page && input.value === "") {
+          e.preventDefault();
+          leavePage();
+        }
         return;
       case "Enter":
         e.preventDefault();

web/src/styles.css

@@ -1472,6 +1472,15 @@ input.leaf-rename:focus {
   padding: var(--sp-2) 0;
 }
 
+/* The action page's header (#151): names the session being acted on, so the
+   target of kill/rename/spawn-similar is never ambiguous. */
+.cmdbar-page-header {
+  padding: var(--sp-2) var(--sp-4);
+  border-bottom: 1px solid var(--border);
+  font-size: var(--fs-12);
+  color: var(--muted);
+}
+
 .cmdbar-group-title {
   padding: var(--sp-2) var(--sp-4) var(--sp-1);
   font-size: var(--fs-11);