fix: ignore unsafe timestamp values

steipete · steipete · commit 41366d3f5190 · 2026-05-28T15:17:13.000-04:00
diff --git a/src/agents/date-time.test.ts b/src/agents/date-time.test.ts
@@ -0,0 +1,20 @@
+import { describe, expect, it } from "vitest";
+import { normalizeTimestamp } from "./date-time.js";
+
+describe("normalizeTimestamp", () => {
+  it("normalizes numeric second and millisecond timestamps", () => {
+    expect(normalizeTimestamp("1700000000")).toEqual({
+      timestampMs: 1_700_000_000_000,
+      timestampUtc: "2023-11-14T22:13:20.000Z",
+    });
+    expect(normalizeTimestamp("1700000000000")).toEqual({
+      timestampMs: 1_700_000_000_000,
+      timestampUtc: "2023-11-14T22:13:20.000Z",
+    });
+  });
+
+  it("ignores unsafe or out-of-range numeric timestamp strings", () => {
+    expect(normalizeTimestamp("9007199254740993")).toBeUndefined();
+    expect(normalizeTimestamp("999999999999999999999999")).toBeUndefined();
+  });
+});
diff --git a/src/agents/date-time.ts b/src/agents/date-time.ts
@@ -5,6 +5,16 @@ export type ResolvedTimeFormat = "12" | "24";
 
 let cachedTimeFormat: ResolvedTimeFormat | undefined;
 
+function buildNormalizedTimestamp(
+  timestampMs: number,
+): { timestampMs: number; timestampUtc: string } | undefined {
+  if (!Number.isSafeInteger(timestampMs)) {
+    return undefined;
+  }
+  const timestampUtc = new Date(timestampMs).toISOString();
+  return { timestampMs, timestampUtc };
+}
+
 export function resolveUserTimezone(configured?: string): string {
   const trimmed = configured?.trim();
   if (trimmed) {
@@ -69,7 +79,11 @@ export function normalizeTimestamp(
   if (timestampMs === undefined || !Number.isFinite(timestampMs)) {
     return undefined;
   }
-  return { timestampMs, timestampUtc: new Date(timestampMs).toISOString() };
+  try {
+    return buildNormalizedTimestamp(timestampMs);
+  } catch {
+    return undefined;
+  }
 }
 
 export function withNormalizedTimestamp<T extends Record<string, unknown>>(
