diff --git a/canvas/src/components/BatchActionBar.tsx b/canvas/src/components/BatchActionBar.tsx
index 5421fbe2..f207e843 100644
--- a/canvas/src/components/BatchActionBar.tsx
+++ b/canvas/src/components/BatchActionBar.tsx
@@ -1,6 +1,6 @@
 "use client";
 
-import { useState } from "react";
+import { useEffect, useState } from "react";
 import { createPortal } from "react-dom";
 import { useCanvasStore } from "@/store/canvas";
 import { ConfirmDialog } from "./ConfirmDialog";
@@ -17,14 +17,32 @@ export function BatchActionBar() {
 
   const [pending, setPending] = useState<BatchAction>(null);
   const [busy, setBusy] = useState(false);
+  // Retry survivorship (QA pr-949 follow-up): when a batch action partial-fails
+  // and leaves a single survivor id, the default `count < 2` gate unmounts the
+  // bar and forces per-node context-menu retry. Track "active failure" so the
+  // bar stays mounted with a single item and the user can click the same action
+  // button to retry without re-selecting. Resets on success or Escape/clear.
+  const [hasFailedBatch, setHasFailedBatch] = useState(false);
 
   const count = selectedNodeIds.size;
-  if (count < 2) return null;
+  // Reset failure flag when the user clears selection (Escape / ✕ button).
+  useEffect(() => {
+    if (count === 0 && hasFailedBatch) setHasFailedBatch(false);
+  }, [count, hasFailedBatch]);
 
+  // Hide when nothing is selected. Hide for single-node selection UNLESS a
+  // partial-failure left a survivor awaiting retry.
+  if (count === 0) return null;
+  if (count < 2 && !hasFailedBatch) return null;
+
+  // Message copy must handle both multi (count >= 2) and single-survivor retry
+  // (count === 1 && hasFailedBatch). Use a helper so we render singular form
+  // only when there is exactly one survivor to act on.
+  const plural = (n: number) => (n === 1 ? "workspace" : "workspaces");
   const confirmMessages: Record<NonNullable<BatchAction>, string> = {
-    restart: `Restart ${count} workspace${count !== 1 ? "s" : ""}? Each will briefly go offline while it restarts.`,
-    pause:   `Pause ${count} workspace${count !== 1 ? "s" : ""}? Their containers will be stopped.`,
-    delete:  `Permanently delete ${count} workspace${count !== 1 ? "s" : ""}? This cannot be undone.`,
+    restart: `Restart ${count} ${plural(count)}? Each will briefly go offline while it restarts.`,
+    pause:   `Pause ${count} ${plural(count)}? Their containers will be stopped.`,
+    delete:  `Permanently delete ${count} ${plural(count)}? This cannot be undone.`,
   };
 
   const confirmLabels: Record<NonNullable<BatchAction>, string> = {
@@ -40,10 +58,18 @@ export function BatchActionBar() {
       if (pending === "restart") await batchRestart();
       if (pending === "pause")   await batchPause();
       if (pending === "delete")  await batchDelete();
-      showToast(`${pending.charAt(0).toUpperCase() + pending.slice(1)} applied to ${count} workspace${count !== 1 ? "s" : ""}`, "success");
+      // Reaching here means every store call fulfilled (the store throws on
+      // any partial failure), so `count` is the actual success count.
+      showToast(`${pending.charAt(0).toUpperCase() + pending.slice(1)} applied to ${count} ${plural(count)}`, "success");
+      setHasFailedBatch(false);
       clearSelection();
-    } catch {
-      showToast(`Batch ${pending} failed`, "error");
+    } catch (e) {
+      const msg = e instanceof Error && e.message ? e.message : `Batch ${pending} failed`;
+      showToast(msg, "error");
+      // Leave the failed IDs selected (the store preserved them) so the user
+      // can retry without re-selecting, and set hasFailedBatch so the bar
+      // stays mounted even if a single survivor remains.
+      setHasFailedBatch(true);
     } finally {
       setBusy(false);
       setPending(null);
diff --git a/canvas/src/components/__tests__/BatchActionBar.test.tsx b/canvas/src/components/__tests__/BatchActionBar.test.tsx
index 55eb786d..4dd9fef6 100644
--- a/canvas/src/components/__tests__/BatchActionBar.test.tsx
+++ b/canvas/src/components/__tests__/BatchActionBar.test.tsx
@@ -41,11 +41,16 @@ vi.mock("@/store/canvas", () => ({
   ),
 }));
 
-// Mock ConfirmDialog to just render buttons for testing
+// Mock ConfirmDialog — renders title + message + buttons so tests can assert
+// on dialog copy (singular/plural, retry prompts, etc.). Keeping the message
+// accessible in the DOM keeps copy-regression tests cheap. (QA recommendation
+// from pr-batch-bar-retry-survivor review, memo qa-batch-bar-retry-survivor-
+// approve-2026-04-19.)
 vi.mock("@/components/ConfirmDialog", () => ({
   ConfirmDialog: ({
     open,
     title,
+    message,
     onConfirm,
     onCancel,
   }: {
@@ -59,7 +64,8 @@ vi.mock("@/components/ConfirmDialog", () => ({
   }) =>
     open ? (
       <div data-testid="confirm-dialog">
-        <span>{title}</span>
+        <span data-testid="confirm-dialog-title">{title}</span>
+        <p data-testid="confirm-dialog-message">{message}</p>
         <button onClick={onConfirm}>confirm</button>
         <button onClick={onCancel}>cancel</button>
       </div>
@@ -125,3 +131,137 @@ describe("BatchActionBar", () => {
     expect(toolbar.getAttribute("aria-label")).toBe("Batch workspace actions");
   });
 });
+
+/**
+ * Retry-survivorship regression tests (QA pr-949 follow-up).
+ *
+ * When batchRestart / batchPause / batchDelete partial-fail, the store
+ * preserves the failed ids in selectedNodeIds and throws. BatchActionBar's
+ * catch handler now sets hasFailedBatch=true so the toolbar stays mounted
+ * even if only 1 survivor remains, letting the user click the same action
+ * button again to retry without re-selecting.
+ *
+ * Prior behavior: `if (count < 2) return null` unmounted the bar when a
+ * single survivor remained, forcing per-node context-menu retry. These
+ * tests pin the new behavior.
+ */
+describe("BatchActionBar — partial-failure retry survivorship", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockSelectedNodeIds = new Set<string>();
+  });
+
+  it("keeps bar mounted with '1 selected' when partial failure leaves one survivor", async () => {
+    // User starts with 2 selected — bar renders.
+    mockSelectedNodeIds = new Set(["ws-ok", "ws-fail"]);
+    // Simulate store's partial-failure behavior: throws after the fulfilled-branch mutations.
+    mockBatchDelete.mockImplementationOnce(() =>
+      Promise.reject(new Error("1/2 delete(s) failed"))
+    );
+
+    const { rerender } = render(<BatchActionBar />);
+    expect(screen.getByText("2 selected")).toBeTruthy();
+
+    // Open confirm dialog → click confirm → execute() runs, rejects, catch sets hasFailedBatch.
+    fireEvent.click(screen.getByText("Delete All"));
+    fireEvent.click(screen.getByText("confirm"));
+    // Let the microtask for the rejection and the subsequent setState run.
+    await new Promise((r) => setTimeout(r, 0));
+
+    // Store would have removed ws-ok and kept ws-fail — simulate the store's
+    // `selectedNodeIds` mutation by swapping the mock and re-rendering.
+    mockSelectedNodeIds = new Set(["ws-fail"]);
+    rerender(<BatchActionBar />);
+
+    // Bar MUST still render (hasFailedBatch=true from the catch), and the
+    // count badge MUST show the survivor count so the user can retry.
+    expect(screen.getByText("1 selected")).toBeTruthy();
+    expect(screen.getByText("Delete All")).toBeTruthy();
+  });
+
+  it("confirm dialog uses singular 'workspace' copy when only one survivor remains", async () => {
+    mockSelectedNodeIds = new Set(["ws-ok", "ws-fail"]);
+    mockBatchDelete.mockImplementationOnce(() =>
+      Promise.reject(new Error("1/2 delete(s) failed"))
+    );
+    const { rerender } = render(<BatchActionBar />);
+    fireEvent.click(screen.getByText("Delete All"));
+    fireEvent.click(screen.getByText("confirm"));
+    await new Promise((r) => setTimeout(r, 0));
+
+    // After failure: 1 survivor remains. Open the confirm dialog again for retry.
+    mockSelectedNodeIds = new Set(["ws-fail"]);
+    rerender(<BatchActionBar />);
+    // Dialog is closed after the prior execute() — re-open via click.
+    fireEvent.click(screen.getByText("Delete All"));
+
+    // Count badge should show the survivor count.
+    expect(screen.getByText("1 selected")).toBeTruthy();
+    // Dialog copy MUST be singular — plural(1) → "workspace" (not "workspaces").
+    // This is the primary user-facing signal that the retry is scoped to one item.
+    const msg = screen.getByTestId("confirm-dialog-message");
+    expect(msg.textContent).toBe(
+      "Permanently delete 1 workspace? This cannot be undone."
+    );
+  });
+
+  it("bar unmounts once a single-survivor selection is cleared (hasFailedBatch resets)", async () => {
+    // Setup: simulate post-failure state with 1 survivor + hasFailedBatch=true.
+    mockSelectedNodeIds = new Set(["ws-ok", "ws-fail"]);
+    mockBatchDelete.mockImplementationOnce(() =>
+      Promise.reject(new Error("1/2 delete(s) failed"))
+    );
+    const { rerender, container } = render(<BatchActionBar />);
+    fireEvent.click(screen.getByText("Delete All"));
+    fireEvent.click(screen.getByText("confirm"));
+    await new Promise((r) => setTimeout(r, 0));
+
+    mockSelectedNodeIds = new Set(["ws-fail"]);
+    rerender(<BatchActionBar />);
+    // Bar mounted with survivor visible.
+    expect(screen.getByText("1 selected")).toBeTruthy();
+
+    // User clears selection (Escape / ✕ button) — selection empties.
+    mockSelectedNodeIds = new Set<string>();
+    rerender(<BatchActionBar />);
+
+    // Bar unmounts. The count===0 early return hides it; the useEffect then
+    // resets hasFailedBatch so a future single-node selection won't re-show
+    // the bar by mistake.
+    expect(container.innerHTML).toBe("");
+  });
+
+  it("hasFailedBatch resets after a successful retry (success clears before clearSelection)", async () => {
+    // Setup: partial-fail with 1 survivor → hasFailedBatch=true.
+    mockSelectedNodeIds = new Set(["ws-ok", "ws-fail"]);
+    mockBatchDelete.mockImplementationOnce(() =>
+      Promise.reject(new Error("1/2 delete(s) failed"))
+    );
+    const { rerender, container } = render(<BatchActionBar />);
+    fireEvent.click(screen.getByText("Delete All"));
+    fireEvent.click(screen.getByText("confirm"));
+    await new Promise((r) => setTimeout(r, 0));
+
+    // Survivor remains → bar still mounted, hasFailedBatch=true.
+    mockSelectedNodeIds = new Set(["ws-fail"]);
+    rerender(<BatchActionBar />);
+    expect(screen.getByText("1 selected")).toBeTruthy();
+
+    // Successful retry: resolve without error → hasFailedBatch clears
+    // before clearSelection() is called. The survivor is then removed
+    // (deleted), leaving count=0.
+    mockBatchDelete.mockImplementationOnce(() => Promise.resolve());
+    fireEvent.click(screen.getByText("Delete All"));
+    fireEvent.click(screen.getByText("confirm"));
+    await new Promise((r) => setTimeout(r, 0));
+
+    // After success + deletion: 0 remaining, hasFailedBatch=false.
+    // Clearing selection must unmount the bar. If hasFailedBatch had NOT
+    // been cleared, the bar would re-mount as a single-node toolbar
+    // (because it would still be in the survivor state from the prior
+    // catch block).
+    mockSelectedNodeIds = new Set<string>();
+    rerender(<BatchActionBar />);
+    expect(container.innerHTML).toBe("");
+  });
+});
diff --git a/canvas/src/store/__tests__/canvas-batch-partial-failure.test.ts b/canvas/src/store/__tests__/canvas-batch-partial-failure.test.ts
new file mode 100644
index 00000000..ee3771ff
--- /dev/null
+++ b/canvas/src/store/__tests__/canvas-batch-partial-failure.test.ts
@@ -0,0 +1,209 @@
+import { describe, it, expect, beforeEach, vi } from "vitest";
+
+// Mock fetch BEFORE importing the store — api.ts uses the global.
+// Individual tests replace this mock to drive ok/!ok per-URL.
+global.fetch = vi.fn();
+
+import { useCanvasStore } from "../canvas";
+import type { WorkspaceData } from "../socket";
+
+function makeWS(overrides: Partial<WorkspaceData> & { id: string }): WorkspaceData {
+  return {
+    name: "WS",
+    role: "agent",
+    tier: 1,
+    status: "online",
+    agent_card: null,
+    url: "http://localhost:9000",
+    parent_id: null,
+    active_tasks: 0,
+    last_error_rate: 0,
+    last_sample_error: "",
+    uptime_seconds: 60,
+    current_task: "",
+    x: 0,
+    y: 0,
+    collapsed: false,
+    runtime: "",
+    budget_limit: null,
+    ...overrides,
+  };
+}
+
+/**
+ * Partial-failure contract for batchRestart / batchPause / batchDelete.
+ *
+ * api.post / api.del throw on non-2xx (src/lib/api.ts:32-34). The store uses
+ * Promise.allSettled which swallows those rejections. Before the fix:
+ *   - batchDelete removed every id unconditionally, producing ghost workspaces.
+ *   - batchRestart cleared needsRestart on every id unconditionally.
+ *   - All three resolved undefined, so BatchActionBar's catch was dead code.
+ *
+ * After the fix: successful ids mutate, failed ids stay selected for retry,
+ * and the method throws an Error summarising the failure count.
+ */
+
+beforeEach(() => {
+  useCanvasStore.setState({
+    nodes: [],
+    edges: [],
+    selectedNodeId: null,
+    selectedNodeIds: new Set<string>(),
+    panelTab: "details",
+    dragOverNodeId: null,
+    contextMenu: null,
+    searchOpen: false,
+    viewport: { x: 0, y: 0, zoom: 1 },
+  });
+  vi.clearAllMocks();
+});
+
+// Drives global.fetch so that a URL matching `failSubstring` returns a 500
+// and every other call returns ok:true with an empty JSON body.
+function installPartialFetch(failSubstring: string) {
+  (global.fetch as unknown as ReturnType<typeof vi.fn>).mockImplementation(
+    (input: RequestInfo | URL) => {
+      const url = typeof input === "string" ? input : input.toString();
+      if (url.includes(failSubstring)) {
+        return Promise.resolve({
+          ok: false,
+          status: 500,
+          json: () => Promise.resolve({}),
+          text: () => Promise.resolve("boom"),
+        } as Response);
+      }
+      return Promise.resolve({
+        ok: true,
+        status: 200,
+        json: () => Promise.resolve({}),
+        text: () => Promise.resolve(""),
+      } as Response);
+    }
+  );
+}
+
+// ──────────────────────────────────────────────────────────────────────────
+// batchDelete
+// ──────────────────────────────────────────────────────────────────────────
+
+describe("batchDelete — partial failure", () => {
+  it("leaves the failed workspace in `nodes` (no ghost removal)", async () => {
+    useCanvasStore.setState({
+      nodes: [
+        { id: "ws-ok", type: "workspace", position: { x: 0, y: 0 }, data: makeWS({ id: "ws-ok" }) },
+        { id: "ws-fail", type: "workspace", position: { x: 0, y: 0 }, data: makeWS({ id: "ws-fail" }) },
+      ],
+      selectedNodeIds: new Set(["ws-ok", "ws-fail"]),
+    });
+    installPartialFetch("ws-fail");
+
+    await expect(useCanvasStore.getState().batchDelete()).rejects.toThrow(/1\/2 delete/);
+
+    const ids = useCanvasStore.getState().nodes.map((n) => n.id);
+    expect(ids).toContain("ws-fail");
+    expect(ids).not.toContain("ws-ok");
+  });
+
+  it("keeps the failed id in selectedNodeIds so the user can retry", async () => {
+    useCanvasStore.setState({
+      nodes: [
+        { id: "ws-ok", type: "workspace", position: { x: 0, y: 0 }, data: makeWS({ id: "ws-ok" }) },
+        { id: "ws-fail", type: "workspace", position: { x: 0, y: 0 }, data: makeWS({ id: "ws-fail" }) },
+      ],
+      selectedNodeIds: new Set(["ws-ok", "ws-fail"]),
+    });
+    installPartialFetch("ws-fail");
+
+    await useCanvasStore.getState().batchDelete().catch(() => {
+      /* swallow — we're asserting state */
+    });
+
+    const sel = useCanvasStore.getState().selectedNodeIds;
+    expect(sel.has("ws-fail")).toBe(true);
+    expect(sel.has("ws-ok")).toBe(false);
+  });
+
+  it("rejects so the BatchActionBar error-toast path runs", async () => {
+    useCanvasStore.setState({
+      nodes: [
+        { id: "ws-fail", type: "workspace", position: { x: 0, y: 0 }, data: makeWS({ id: "ws-fail" }) },
+      ],
+      selectedNodeIds: new Set(["ws-fail"]),
+    });
+    installPartialFetch("ws-fail");
+
+    await expect(useCanvasStore.getState().batchDelete()).rejects.toBeInstanceOf(Error);
+  });
+});
+
+// ──────────────────────────────────────────────────────────────────────────
+// batchRestart
+// ──────────────────────────────────────────────────────────────────────────
+
+describe("batchRestart — partial failure", () => {
+  it("keeps needsRestart=true on the workspace that failed to restart", async () => {
+    useCanvasStore.setState({
+      nodes: [
+        {
+          id: "ws-ok",
+          type: "workspace",
+          position: { x: 0, y: 0 },
+          data: { ...makeWS({ id: "ws-ok" }), needsRestart: true } as WorkspaceData & { needsRestart: boolean },
+        },
+        {
+          id: "ws-fail",
+          type: "workspace",
+          position: { x: 0, y: 0 },
+          data: { ...makeWS({ id: "ws-fail" }), needsRestart: true } as WorkspaceData & { needsRestart: boolean },
+        },
+      ],
+      selectedNodeIds: new Set(["ws-ok", "ws-fail"]),
+    });
+    installPartialFetch("ws-fail");
+
+    await useCanvasStore.getState().batchRestart().catch(() => {
+      /* swallow — we're asserting state */
+    });
+
+    const byId = Object.fromEntries(
+      useCanvasStore.getState().nodes.map((n) => [n.id, n.data as WorkspaceData & { needsRestart?: boolean }])
+    );
+    expect(byId["ws-ok"].needsRestart).toBe(false);
+    expect(byId["ws-fail"].needsRestart).toBe(true);
+  });
+
+  it("rejects so the BatchActionBar error-toast path runs", async () => {
+    useCanvasStore.setState({
+      nodes: [
+        {
+          id: "ws-fail",
+          type: "workspace",
+          position: { x: 0, y: 0 },
+          data: { ...makeWS({ id: "ws-fail" }), needsRestart: true } as WorkspaceData & { needsRestart: boolean },
+        },
+      ],
+      selectedNodeIds: new Set(["ws-fail"]),
+    });
+    installPartialFetch("ws-fail");
+
+    await expect(useCanvasStore.getState().batchRestart()).rejects.toBeInstanceOf(Error);
+  });
+});
+
+// ──────────────────────────────────────────────────────────────────────────
+// batchPause
+// ──────────────────────────────────────────────────────────────────────────
+
+describe("batchPause — partial failure", () => {
+  it("rejects so the BatchActionBar error-toast path runs", async () => {
+    useCanvasStore.setState({
+      nodes: [
+        { id: "ws-fail", type: "workspace", position: { x: 0, y: 0 }, data: makeWS({ id: "ws-fail" }) },
+      ],
+      selectedNodeIds: new Set(["ws-fail"]),
+    });
+    installPartialFetch("ws-fail");
+
+    await expect(useCanvasStore.getState().batchPause()).rejects.toBeInstanceOf(Error);
+  });
+});
diff --git a/canvas/src/store/canvas.ts b/canvas/src/store/canvas.ts
index f0c73b6d..7c7cc314 100644
--- a/canvas/src/store/canvas.ts
+++ b/canvas/src/store/canvas.ts
@@ -126,22 +126,56 @@ export const useCanvasStore = create<CanvasState>((set, get) => ({
   clearSelection: () => set({ selectedNodeIds: new Set<string>() }),
   batchRestart: async () => {
     const ids = Array.from(get().selectedNodeIds);
-    await Promise.allSettled(ids.map((id) => api.post(`/workspaces/${id}/restart`)));
-    for (const id of ids) {
-      get().updateNodeData(id, { needsRestart: false });
+    const results = await Promise.allSettled(
+      ids.map((id) => api.post(`/workspaces/${id}/restart`))
+    );
+    const failed: string[] = [];
+    results.forEach((r, i) => {
+      if (r.status === "fulfilled") {
+        get().updateNodeData(ids[i], { needsRestart: false });
+      } else {
+        failed.push(ids[i]);
+      }
+    });
+    // Keep failed IDs selected so the user can retry; drop the successful ones.
+    set({ selectedNodeIds: new Set(failed) });
+    if (failed.length > 0) {
+      throw new Error(`${failed.length}/${ids.length} restart(s) failed`);
     }
   },
   batchPause: async () => {
     const ids = Array.from(get().selectedNodeIds);
-    await Promise.allSettled(ids.map((id) => api.post(`/workspaces/${id}/pause`)));
+    const results = await Promise.allSettled(
+      ids.map((id) => api.post(`/workspaces/${id}/pause`))
+    );
+    const failed: string[] = [];
+    results.forEach((r, i) => {
+      if (r.status !== "fulfilled") failed.push(ids[i]);
+    });
+    set({ selectedNodeIds: new Set(failed) });
+    if (failed.length > 0) {
+      throw new Error(`${failed.length}/${ids.length} pause(s) failed`);
+    }
   },
   batchDelete: async () => {
     const ids = Array.from(get().selectedNodeIds);
-    await Promise.allSettled(ids.map((id) => api.del(`/workspaces/${id}`)));
-    for (const id of ids) {
-      get().removeNode(id);
+    const results = await Promise.allSettled(
+      ids.map((id) => api.del(`/workspaces/${id}`))
+    );
+    const failed: string[] = [];
+    results.forEach((r, i) => {
+      if (r.status === "fulfilled") {
+        get().removeNode(ids[i]);
+      } else {
+        failed.push(ids[i]);
+      }
+    });
+    // Keep failed IDs selected so the user can retry; the successful ones
+    // were already removed from `nodes` above.
+    set({ selectedNodeIds: new Set(failed) });
+    if (failed.length > 0) {
+      throw new Error(`${failed.length}/${ids.length} delete(s) failed`);
     }
-    set({ selectedNodeIds: new Set<string>() });
   },
   wsStatus: "connecting",
   setWsStatus: (status) => set({ wsStatus: status }),