From 961bde27feae2809ef294608cb8463403305e521 Mon Sep 17 00:00:00 2001
From: Vignesh Natarajan <vigneshnatarajan92@gmail.com>
Date: Sat, 21 Feb 2026 20:18:11 -0800
Subject: [PATCH] Cron: guard missing expr in schedule parsing

---
 CHANGELOG.md                                      |  1 +
 src/cron/schedule.test.ts                         | 12 ++++++++++++
 src/cron/schedule.ts                              |  6 +++++-
 .../service/jobs.schedule-error-isolation.test.ts | 15 +++++++++++++++
 src/cron/stagger.test.ts                          |  9 +++++++++
 src/cron/stagger.ts                               |  4 +++-
 6 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 21babf4e1ea..a9ab01cd637 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -21,6 +21,7 @@ Docs: https://docs.openclaw.ai
 - Agents/Ollama: preserve unsafe integer tool-call arguments as exact strings during NDJSON parsing, preventing large numeric IDs from being rounded before tool execution. (#23170) Thanks @BestJoester.
 - Cron/Gateway: keep `cron.list` and `cron.status` responsive during startup catch-up by avoiding a long-held cron lock while missed jobs execute. (#23106) Thanks @jayleekr.
 - Gateway/Config reload: compare array-valued config paths structurally during diffing so unchanged `memory.qmd.paths` and `memory.qmd.scope.rules` no longer trigger false restart-required reloads. (#23185) Thanks @rex05ai.
+- Cron/Scheduling: validate runtime cron expressions before schedule/stagger evaluation so malformed persisted jobs report a clear `invalid cron schedule: expr is required` error instead of crashing with `undefined.trim` failures and auto-disable churn. (#23223) Thanks @asimons81.
 - TUI/Input: enable multiline-paste burst coalescing on macOS Terminal.app and iTerm so pasted blocks no longer submit line-by-line as separate messages. (#18809) Thanks @fwends.
 - TUI/Status: request immediate renders after setting `sending`/`waiting` activity states so in-flight runs always show visible progress indicators instead of appearing idle until completion. (#21549) Thanks @13Guinness.
 - Agents/Fallbacks: treat JSON payloads with `type: "api_error"` + `"Internal server error"` as transient failover errors so Anthropic 500-style failures trigger model fallback. (#23193) Thanks @jarvis-lane.
diff --git a/src/cron/schedule.test.ts b/src/cron/schedule.test.ts
index 3a4e66f9f15..1bea936b274 100644
--- a/src/cron/schedule.test.ts
+++ b/src/cron/schedule.test.ts
@@ -13,6 +13,18 @@ describe("cron schedule", () => {
     expect(next).toBe(Date.parse("2025-12-17T17:00:00.000Z"));
   });
 
+  it("throws a clear error when cron expr is missing at runtime", () => {
+    const nowMs = Date.parse("2025-12-13T00:00:00.000Z");
+    expect(() =>
+      computeNextRunAtMs(
+        {
+          kind: "cron",
+        } as unknown as { kind: "cron"; expr: string; tz?: string },
+        nowMs,
+      ),
+    ).toThrow("invalid cron schedule: expr is required");
+  });
+
   it("computes next run for every schedule", () => {
     const anchor = Date.parse("2025-12-13T00:00:00.000Z");
     const now = anchor + 10_000;
diff --git a/src/cron/schedule.ts b/src/cron/schedule.ts
index 140cbb82936..d80aaa440cb 100644
--- a/src/cron/schedule.ts
+++ b/src/cron/schedule.ts
@@ -41,7 +41,11 @@ export function computeNextRunAtMs(schedule: CronSchedule, nowMs: number): numbe
     return anchor + steps * everyMs;
   }
 
-  const expr = schedule.expr.trim();
+  const exprSource = (schedule as { expr?: unknown }).expr;
+  if (typeof exprSource !== "string") {
+    throw new Error("invalid cron schedule: expr is required");
+  }
+  const expr = exprSource.trim();
   if (!expr) {
     return undefined;
   }
diff --git a/src/cron/service/jobs.schedule-error-isolation.test.ts b/src/cron/service/jobs.schedule-error-isolation.test.ts
index 064ff37c1ee..84cd8e0a1e9 100644
--- a/src/cron/service/jobs.schedule-error-isolation.test.ts
+++ b/src/cron/service/jobs.schedule-error-isolation.test.ts
@@ -186,4 +186,19 @@ describe("cron schedule error isolation", () => {
     expect(badJob.state.lastError).toMatch(/^schedule error:/);
     expect(badJob.state.lastError).toBeTruthy();
   });
+
+  it("records a clear schedule error when cron expr is missing", () => {
+    const badJob = createJob({
+      id: "missing-expr",
+      name: "Missing Expr",
+      schedule: { kind: "cron" } as unknown as CronJob["schedule"],
+    });
+    const state = createMockState([badJob]);
+
+    recomputeNextRuns(state);
+
+    expect(badJob.state.lastError).toContain("invalid cron schedule: expr is required");
+    expect(badJob.state.lastError).not.toContain("Cannot read properties of undefined");
+    expect(badJob.state.scheduleErrorCount).toBe(1);
+  });
 });
diff --git a/src/cron/stagger.test.ts b/src/cron/stagger.test.ts
index d62e3fe3d61..a2c2cdd60ec 100644
--- a/src/cron/stagger.test.ts
+++ b/src/cron/stagger.test.ts
@@ -33,4 +33,13 @@ describe("cron stagger helpers", () => {
     expect(resolveCronStaggerMs({ kind: "cron", expr: "0 * * * *", staggerMs: 0 })).toBe(0);
     expect(resolveCronStaggerMs({ kind: "cron", expr: "15 * * * *" })).toBe(0);
   });
+
+  it("handles missing runtime expr values without throwing", () => {
+    expect(() =>
+      resolveCronStaggerMs({ kind: "cron" } as unknown as { kind: "cron"; expr: string }),
+    ).not.toThrow();
+    expect(
+      resolveCronStaggerMs({ kind: "cron" } as unknown as { kind: "cron"; expr: string }),
+    ).toBe(0);
+  });
 });
diff --git a/src/cron/stagger.ts b/src/cron/stagger.ts
index 2eecdd18f33..4b251dfb43c 100644
--- a/src/cron/stagger.ts
+++ b/src/cron/stagger.ts
@@ -41,5 +41,7 @@ export function resolveCronStaggerMs(schedule: Extract<CronSchedule, { kind: "cr
   if (explicit !== undefined) {
     return explicit;
   }
-  return resolveDefaultCronStaggerMs(schedule.expr) ?? 0;
+  const expr = (schedule as { expr?: unknown }).expr;
+  const cronExpr = typeof expr === "string" ? expr : "";
+  return resolveDefaultCronStaggerMs(cronExpr) ?? 0;
 }