diff --git a/src/cron/service.list-page-sort-guards.test.ts b/src/cron/service.list-page-sort-guards.test.ts
new file mode 100644
index 00000000000..69349147adf
--- /dev/null
+++ b/src/cron/service.list-page-sort-guards.test.ts
@@ -0,0 +1,53 @@
+import { describe, expect, it } from "vitest";
+import { createMockCronStateForJobs } from "./service.test-harness.js";
+import { listPage } from "./service/ops.js";
+import type { CronJob } from "./types.js";
+
+function createBaseJob(overrides?: Partial<CronJob>): CronJob {
+  return {
+    id: "job-1",
+    name: "job",
+    enabled: true,
+    schedule: { kind: "cron", expr: "*/5 * * * *", tz: "UTC" },
+    sessionTarget: "main",
+    wakeMode: "now",
+    payload: { kind: "systemEvent", text: "tick" },
+    state: { nextRunAtMs: Date.parse("2026-02-27T15:30:00.000Z") },
+    createdAtMs: Date.parse("2026-02-27T15:00:00.000Z"),
+    updatedAtMs: Date.parse("2026-02-27T15:05:00.000Z"),
+    ...overrides,
+  };
+}
+
+describe("cron listPage sort guards", () => {
+  it("does not throw when sorting by name with malformed name fields", async () => {
+    const jobs = [
+      createBaseJob({ id: "job-a", name: undefined as unknown as string }),
+      createBaseJob({ id: "job-b", name: "beta" }),
+    ];
+    const state = createMockCronStateForJobs({ jobs });
+
+    const page = await listPage(state, { sortBy: "name", sortDir: "asc" });
+    expect(page.jobs).toHaveLength(2);
+  });
+
+  it("does not throw when tie-break sorting encounters missing ids", async () => {
+    const nextRunAtMs = Date.parse("2026-02-27T15:30:00.000Z");
+    const jobs = [
+      createBaseJob({
+        id: undefined as unknown as string,
+        name: "alpha",
+        state: { nextRunAtMs },
+      }),
+      createBaseJob({
+        id: undefined as unknown as string,
+        name: "alpha",
+        state: { nextRunAtMs },
+      }),
+    ];
+    const state = createMockCronStateForJobs({ jobs });
+
+    const page = await listPage(state, { sortBy: "nextRunAtMs", sortDir: "asc" });
+    expect(page.jobs).toHaveLength(2);
+  });
+});
diff --git a/src/cron/service/ops.ts b/src/cron/service/ops.ts
index bc2ec0934a4..af552acaabb 100644
--- a/src/cron/service/ops.ts
+++ b/src/cron/service/ops.ts
@@ -164,7 +164,9 @@ function sortJobs(jobs: CronJob[], sortBy: CronJobsSortBy, sortDir: CronSortDir)
   return jobs.toSorted((a, b) => {
     let cmp = 0;
     if (sortBy === "name") {
-      cmp = a.name.localeCompare(b.name, undefined, { sensitivity: "base" });
+      const aName = typeof a.name === "string" ? a.name : "";
+      const bName = typeof b.name === "string" ? b.name : "";
+      cmp = aName.localeCompare(bName, undefined, { sensitivity: "base" });
     } else if (sortBy === "updatedAtMs") {
       cmp = a.updatedAtMs - b.updatedAtMs;
     } else {
@@ -183,7 +185,9 @@ function sortJobs(jobs: CronJob[], sortBy: CronJobsSortBy, sortDir: CronSortDir)
     if (cmp !== 0) {
       return cmp * dir;
     }
-    return a.id.localeCompare(b.id);
+    const aId = typeof a.id === "string" ? a.id : "";
+    const bId = typeof b.id === "string" ? b.id : "";
+    return aId.localeCompare(bId);
   });
 }