diff --git a/CHANGELOG.md b/CHANGELOG.md
index b95d8a0c2eb..f6fc92252e6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Cron/Delivery: disable the agent messaging tool when `delivery.mode` is `"none"` so cron output is not sent to Telegram or other channels. (#21808)
 - Feishu/Reply media attachments: send Feishu reply `mediaUrl`/`mediaUrls` payloads as attachments alongside text/streamed replies in the reply dispatcher, including legacy fallback when `mediaUrls` is empty. (#28959)
 - Feishu/Reaction notifications: add `channels.feishu.reactionNotifications` (`off | own | all`, default `own`) so operators can disable reaction ingress or allow all verified reaction events (not only bot-authored message reactions). (#28529)
 - Feishu/Outbound session routing: stop assuming bare `oc_` identifiers are always group chats, honor explicit `dm:`/`group:` prefixes for `oc_` chat IDs, and default ambiguous bare `oc_` targets to direct routing to avoid DM session misclassification. (#10407) Thanks @Bermudarat.
diff --git a/src/cron/delivery.test.ts b/src/cron/delivery.test.ts
index d2e9223cd13..7cc690f79cf 100644
--- a/src/cron/delivery.test.ts
+++ b/src/cron/delivery.test.ts
@@ -43,29 +43,16 @@ describe("resolveCronDeliveryPlan", () => {
     expect(plan.requested).toBe(false);
   });
 
-  it("passes through accountId from delivery config", () => {
+  it("resolves mode=none with requested=false and no channel (#21808)", () => {
     const plan = resolveCronDeliveryPlan(
       makeJob({
-        delivery: {
-          mode: "announce",
-          channel: "telegram",
-          to: "-1003816714067",
-          accountId: "coordinator",
-        },
+        delivery: { mode: "none", to: "telegram:123" },
       }),
     );
-    expect(plan.mode).toBe("announce");
-    expect(plan.accountId).toBe("coordinator");
-    expect(plan.to).toBe("-1003816714067");
-  });
-
-  it("returns undefined accountId when not set", () => {
-    const plan = resolveCronDeliveryPlan(
-      makeJob({
-        delivery: { mode: "announce", channel: "telegram", to: "123" },
-      }),
-    );
-    expect(plan.accountId).toBeUndefined();
+    expect(plan.mode).toBe("none");
+    expect(plan.requested).toBe(false);
+    expect(plan.channel).toBeUndefined();
+    expect(plan.to).toBe("telegram:123");
   });
 
   it("resolves webhook mode without channel routing", () => {
diff --git a/src/cron/isolated-agent/run.ts b/src/cron/isolated-agent/run.ts
index f9875e1212a..16a69cf5711 100644
--- a/src/cron/isolated-agent/run.ts
+++ b/src/cron/isolated-agent/run.ts
@@ -470,7 +470,7 @@ export async function runCronIsolatedAgentTurn(params: {
           // was successfully resolved. When resolution fails the agent should not
           // be blocked by a target it cannot satisfy (#27898).
           requireExplicitMessageTarget: deliveryRequested && resolvedDelivery.ok,
-          disableMessageTool: deliveryRequested,
+          disableMessageTool: deliveryRequested || deliveryPlan.mode === "none",
           abortSignal,
         });
       },