diff --git a/src/cron/legacy-delivery.ts b/src/cron/legacy-delivery.ts
index 8dcc6ecda5d..0474f5d7b95 100644
--- a/src/cron/legacy-delivery.ts
+++ b/src/cron/legacy-delivery.ts
@@ -42,6 +42,102 @@ export function buildDeliveryFromLegacyPayload(
   return next;
 }
 
+export function buildDeliveryPatchFromLegacyPayload(payload: Record<string, unknown>) {
+  const deliver = payload.deliver;
+  const channelRaw =
+    typeof payload.channel === "string" && payload.channel.trim()
+      ? payload.channel.trim().toLowerCase()
+      : typeof payload.provider === "string" && payload.provider.trim()
+        ? payload.provider.trim().toLowerCase()
+        : "";
+  const toRaw = typeof payload.to === "string" ? payload.to.trim() : "";
+  const next: Record<string, unknown> = {};
+  let hasPatch = false;
+
+  if (deliver === false) {
+    next.mode = "none";
+    hasPatch = true;
+  } else if (
+    deliver === true ||
+    channelRaw ||
+    toRaw ||
+    typeof payload.bestEffortDeliver === "boolean"
+  ) {
+    next.mode = "announce";
+    hasPatch = true;
+  }
+  if (channelRaw) {
+    next.channel = channelRaw;
+    hasPatch = true;
+  }
+  if (toRaw) {
+    next.to = toRaw;
+    hasPatch = true;
+  }
+  if (typeof payload.bestEffortDeliver === "boolean") {
+    next.bestEffort = payload.bestEffortDeliver;
+    hasPatch = true;
+  }
+
+  return hasPatch ? next : null;
+}
+
+export function mergeLegacyDeliveryInto(
+  delivery: Record<string, unknown>,
+  payload: Record<string, unknown>,
+) {
+  const patch = buildDeliveryPatchFromLegacyPayload(payload);
+  if (!patch) {
+    return { delivery, mutated: false };
+  }
+
+  const next = { ...delivery };
+  let mutated = false;
+
+  if ("mode" in patch && patch.mode !== next.mode) {
+    next.mode = patch.mode;
+    mutated = true;
+  }
+  if ("channel" in patch && patch.channel !== next.channel) {
+    next.channel = patch.channel;
+    mutated = true;
+  }
+  if ("to" in patch && patch.to !== next.to) {
+    next.to = patch.to;
+    mutated = true;
+  }
+  if ("bestEffort" in patch && patch.bestEffort !== next.bestEffort) {
+    next.bestEffort = patch.bestEffort;
+    mutated = true;
+  }
+
+  return { delivery: next, mutated };
+}
+
+export function normalizeLegacyDeliveryInput(params: {
+  delivery?: Record<string, unknown> | null;
+  payload?: Record<string, unknown> | null;
+}) {
+  if (!params.payload || !hasLegacyDeliveryHints(params.payload)) {
+    return {
+      delivery: params.delivery ?? undefined,
+      mutated: false,
+    };
+  }
+
+  const nextDelivery = params.delivery
+    ? mergeLegacyDeliveryInto(params.delivery, params.payload)
+    : {
+        delivery: buildDeliveryFromLegacyPayload(params.payload),
+        mutated: true,
+      };
+  stripLegacyDeliveryFields(params.payload);
+  return {
+    delivery: nextDelivery.delivery,
+    mutated: true,
+  };
+}
+
 export function stripLegacyDeliveryFields(payload: Record<string, unknown>) {
   if ("deliver" in payload) {
     delete payload.deliver;
diff --git a/src/cron/normalize.ts b/src/cron/normalize.ts
index fe06eaf2f46..5a6c66ff356 100644
--- a/src/cron/normalize.ts
+++ b/src/cron/normalize.ts
@@ -1,10 +1,6 @@
 import { sanitizeAgentId } from "../routing/session-key.js";
 import { isRecord } from "../utils.js";
-import {
-  buildDeliveryFromLegacyPayload,
-  hasLegacyDeliveryHints,
-  stripLegacyDeliveryFields,
-} from "./legacy-delivery.js";
+import { normalizeLegacyDeliveryInput } from "./legacy-delivery.js";
 import { parseAbsoluteTimeMs } from "./parse.js";
 import { migrateLegacyCronPayload } from "./payload-migration.js";
 import { inferLegacyName } from "./service/normalize.js";
@@ -469,14 +465,20 @@ export function normalizeCronJobInput(
     const isIsolatedAgentTurn =
       sessionTarget === "isolated" || (sessionTarget === "" && payloadKind === "agentTurn");
     const hasDelivery = "delivery" in next && next.delivery !== undefined;
-    const hasLegacyDelivery = payload ? hasLegacyDeliveryHints(payload) : false;
-    if (!hasDelivery && isIsolatedAgentTurn && payloadKind === "agentTurn") {
-      if (payload && hasLegacyDelivery) {
-        next.delivery = buildDeliveryFromLegacyPayload(payload);
-        stripLegacyDeliveryFields(payload);
-      } else {
-        next.delivery = { mode: "announce" };
-      }
+    const normalizedLegacy = normalizeLegacyDeliveryInput({
+      delivery: isRecord(next.delivery) ? next.delivery : null,
+      payload,
+    });
+    if (normalizedLegacy.mutated && normalizedLegacy.delivery) {
+      next.delivery = normalizedLegacy.delivery;
+    }
+    if (
+      !hasDelivery &&
+      !normalizedLegacy.delivery &&
+      isIsolatedAgentTurn &&
+      payloadKind === "agentTurn"
+    ) {
+      next.delivery = { mode: "announce" };
     }
   }
 
diff --git a/src/cron/service.jobs.test.ts b/src/cron/service.jobs.test.ts
index ae77f488f0a..053ea8764de 100644
--- a/src/cron/service.jobs.test.ts
+++ b/src/cron/service.jobs.test.ts
@@ -589,19 +589,6 @@ describe("createJob delivery defaults", () => {
     expect(job.delivery).toEqual({ mode: "none" });
   });
 
-  it("preserves legacy payload deliver=false when explicit delivery is omitted", () => {
-    const state = createMockState(now);
-    const job = createJob(state, {
-      name: "isolated-legacy-no-deliver",
-      enabled: true,
-      schedule: { kind: "every", everyMs: 60_000 },
-      sessionTarget: "isolated",
-      wakeMode: "now",
-      payload: { kind: "agentTurn", message: "hello", deliver: false } as never,
-    });
-    expect(job.delivery).toEqual({ mode: "none" });
-  });
-
   it("does not set delivery for main systemEvent jobs without explicit delivery", () => {
     const state = createMockState(now, { defaultAgentId: "main" });
     const job = createJob(state, {
diff --git a/src/cron/service/initial-delivery.ts b/src/cron/service/initial-delivery.ts
index 8aff8ef4452..9dc2eb908d5 100644
--- a/src/cron/service/initial-delivery.ts
+++ b/src/cron/service/initial-delivery.ts
@@ -1,17 +1,9 @@
-import { buildDeliveryFromLegacyPayload, hasLegacyDeliveryHints } from "../legacy-delivery.js";
 import type { CronDelivery, CronJobCreate } from "../types.js";
 
 export function resolveInitialCronDelivery(input: CronJobCreate): CronDelivery | undefined {
   if (input.delivery) {
     return input.delivery;
   }
-  const payloadRecord =
-    input.payload && typeof input.payload === "object"
-      ? (input.payload as Record<string, unknown>)
-      : undefined;
-  if (payloadRecord && hasLegacyDeliveryHints(payloadRecord)) {
-    return buildDeliveryFromLegacyPayload(payloadRecord) as CronDelivery;
-  }
   if (input.sessionTarget === "isolated" && input.payload.kind === "agentTurn") {
     return { mode: "announce" };
   }
diff --git a/src/cron/service/ops.ts b/src/cron/service/ops.ts
index 14758c5df34..2b86b7253c2 100644
--- a/src/cron/service/ops.ts
+++ b/src/cron/service/ops.ts
@@ -1,3 +1,4 @@
+import { normalizeCronJobCreate } from "../normalize.js";
 import type { CronJob, CronJobCreate, CronJobPatch } from "../types.js";
 import {
   applyJobPatch,
@@ -234,7 +235,11 @@ export async function add(state: CronServiceState, input: CronJobCreate) {
   return await locked(state, async () => {
     warnIfDisabled(state, "add");
     await ensureLoaded(state);
-    const job = createJob(state, input);
+    const normalizedInput = normalizeCronJobCreate(input);
+    if (!normalizedInput) {
+      throw new Error("invalid cron job input");
+    }
+    const job = createJob(state, normalizedInput);
     state.store?.jobs.push(job);
 
     // Defensive: recompute all next-run times to ensure consistency
diff --git a/src/cron/service/store.ts b/src/cron/service/store.ts
index 0a52197bf81..2c40ac50643 100644
--- a/src/cron/service/store.ts
+++ b/src/cron/service/store.ts
@@ -1,9 +1,5 @@
 import fs from "node:fs";
-import {
-  buildDeliveryFromLegacyPayload,
-  hasLegacyDeliveryHints,
-  stripLegacyDeliveryFields,
-} from "../legacy-delivery.js";
+import { normalizeLegacyDeliveryInput } from "../legacy-delivery.js";
 import { parseAbsoluteTimeMs } from "../parse.js";
 import { migrateLegacyCronPayload } from "../payload-migration.js";
 import { coerceFiniteScheduleNumber } from "../schedule.js";
@@ -14,69 +10,6 @@ import { recomputeNextRuns } from "./jobs.js";
 import { inferLegacyName, normalizeOptionalText } from "./normalize.js";
 import type { CronServiceState } from "./state.js";
 
-function buildDeliveryPatchFromLegacyPayload(payload: Record<string, unknown>) {
-  const deliver = payload.deliver;
-  const channelRaw =
-    typeof payload.channel === "string" ? payload.channel.trim().toLowerCase() : "";
-  const toRaw = typeof payload.to === "string" ? payload.to.trim() : "";
-  const next: Record<string, unknown> = {};
-  let hasPatch = false;
-
-  if (deliver === false) {
-    next.mode = "none";
-    hasPatch = true;
-  } else if (deliver === true || toRaw) {
-    next.mode = "announce";
-    hasPatch = true;
-  }
-  if (channelRaw) {
-    next.channel = channelRaw;
-    hasPatch = true;
-  }
-  if (toRaw) {
-    next.to = toRaw;
-    hasPatch = true;
-  }
-  if (typeof payload.bestEffortDeliver === "boolean") {
-    next.bestEffort = payload.bestEffortDeliver;
-    hasPatch = true;
-  }
-
-  return hasPatch ? next : null;
-}
-
-function mergeLegacyDeliveryInto(
-  delivery: Record<string, unknown>,
-  payload: Record<string, unknown>,
-) {
-  const patch = buildDeliveryPatchFromLegacyPayload(payload);
-  if (!patch) {
-    return { delivery, mutated: false };
-  }
-
-  const next = { ...delivery };
-  let mutated = false;
-
-  if ("mode" in patch && patch.mode !== next.mode) {
-    next.mode = patch.mode;
-    mutated = true;
-  }
-  if ("channel" in patch && patch.channel !== next.channel) {
-    next.channel = patch.channel;
-    mutated = true;
-  }
-  if ("to" in patch && patch.to !== next.to) {
-    next.to = patch.to;
-    mutated = true;
-  }
-  if ("bestEffort" in patch && patch.bestEffort !== next.bestEffort) {
-    next.bestEffort = patch.bestEffort;
-    mutated = true;
-  }
-
-  return { delivery: next, mutated };
-}
-
 function normalizePayloadKind(payload: Record<string, unknown>) {
   const raw = typeof payload.kind === "string" ? payload.kind.trim().toLowerCase() : "";
   if (raw === "agentturn") {
@@ -512,30 +445,25 @@ export async function ensureLoaded(
     const isIsolatedAgentTurn =
       sessionTarget === "isolated" || (sessionTarget === "" && payloadKind === "agentTurn");
     const hasDelivery = delivery && typeof delivery === "object" && !Array.isArray(delivery);
-    const hasLegacyDelivery = payloadRecord ? hasLegacyDeliveryHints(payloadRecord) : false;
+    const normalizedLegacy = normalizeLegacyDeliveryInput({
+      delivery: hasDelivery ? (delivery as Record<string, unknown>) : null,
+      payload: payloadRecord,
+    });
 
     if (isIsolatedAgentTurn && payloadKind === "agentTurn") {
-      if (!hasDelivery) {
-        raw.delivery =
-          payloadRecord && hasLegacyDelivery
-            ? buildDeliveryFromLegacyPayload(payloadRecord)
-            : { mode: "announce" };
-        mutated = true;
-      }
-      if (payloadRecord && hasLegacyDelivery) {
-        if (hasDelivery) {
-          const merged = mergeLegacyDeliveryInto(
-            delivery as Record<string, unknown>,
-            payloadRecord,
-          );
-          if (merged.mutated) {
-            raw.delivery = merged.delivery;
-            mutated = true;
-          }
-        }
-        stripLegacyDeliveryFields(payloadRecord);
+      if (!hasDelivery && normalizedLegacy.delivery) {
+        raw.delivery = normalizedLegacy.delivery;
+        mutated = true;
+      } else if (!hasDelivery) {
+        raw.delivery = { mode: "announce" };
+        mutated = true;
+      } else if (normalizedLegacy.mutated && normalizedLegacy.delivery) {
+        raw.delivery = normalizedLegacy.delivery;
         mutated = true;
       }
+    } else if (normalizedLegacy.mutated && normalizedLegacy.delivery) {
+      raw.delivery = normalizedLegacy.delivery;
+      mutated = true;
     }
   }
   state.store = { version: 1, jobs: jobs as unknown as CronJob[] };