fix(discord): guard timeout expiry dates

extensions/discord/src/send.creates-thread.test.ts

@@ -121,6 +121,7 @@ beforeEach(() => {
 
 afterEach(() => {
   vi.useRealTimers();
+  vi.restoreAllMocks();
 });
 
 afterAll(() => {
@@ -322,6 +323,18 @@ describe("sendMessageDiscord", () => {
     ).toBeTypeOf("string");
   });
 
+  it("rejects timeout durations outside Date range", async () => {
+    const { rest, patchMock } = makeDiscordRest();
+
+    await expect(
+      timeoutMemberDiscord(
+        { guildId: "g1", userId: "u1", durationMinutes: 8_640_000_000_000_001 },
+        discordClientOpts(rest),
+      ),
+    ).rejects.toThrow("Discord timeout duration is outside the supported Date range");
+    expect(patchMock).not.toHaveBeenCalled();
+  });
+
   it("adds and removes roles", async () => {
     const { rest, putMock, deleteMock } = makeDiscordRest();
     putMock.mockResolvedValue({});

extensions/discord/src/send.guild.ts

@@ -6,6 +6,7 @@ import type {
   APIVoiceState,
   RESTPostAPIGuildScheduledEventJSONBody,
 } from "discord-api-types/v10";
+import { timestampMsToIsoString } from "openclaw/plugin-sdk/number-runtime";
 import { normalizeOptionalLowercaseString } from "openclaw/plugin-sdk/string-coerce-runtime";
 import { loadWebMediaRaw } from "openclaw/plugin-sdk/web-media";
 import {
@@ -139,7 +140,10 @@ export async function timeoutMemberDiscord(
   let until = payload.until;
   if (!until && payload.durationMinutes) {
     const ms = payload.durationMinutes * 60 * 1000;
-    until = new Date(Date.now() + ms).toISOString();
+    until = timestampMsToIsoString(Date.now() + ms);
+    if (!until) {
+      throw new Error("Discord timeout duration is outside the supported Date range");
+    }
   }
   return await timeoutGuildMember(rest, payload.guildId, payload.userId, {
     body: { communication_disabled_until: until ?? null },