diff --git a/src/cron/service.runs-one-shot-main-job-disables-it.test.ts b/src/cron/service.runs-one-shot-main-job-disables-it.test.ts
index 1cc3eca03c..bbee9cf7e8 100644
--- a/src/cron/service.runs-one-shot-main-job-disables-it.test.ts
+++ b/src/cron/service.runs-one-shot-main-job-disables-it.test.ts
@@ -200,6 +200,49 @@ describe("CronService", () => {
     await store.cleanup();
   });
 
+  it("passes agentId to runHeartbeatOnce for main-session wakeMode now jobs", async () => {
+    const store = await makeStorePath();
+    const enqueueSystemEvent = vi.fn();
+    const requestHeartbeatNow = vi.fn();
+    const runHeartbeatOnce = vi.fn(async () => ({ status: "ran" as const, durationMs: 1 }));
+
+    const cron = new CronService({
+      storePath: store.storePath,
+      cronEnabled: true,
+      log: noopLogger,
+      enqueueSystemEvent,
+      requestHeartbeatNow,
+      runHeartbeatOnce,
+      runIsolatedAgentJob: vi.fn(async () => ({ status: "ok" })),
+    });
+
+    await cron.start();
+    const job = await cron.add({
+      name: "wakeMode now with agent",
+      agentId: "ops",
+      enabled: true,
+      schedule: { kind: "at", at: new Date(1).toISOString() },
+      sessionTarget: "main",
+      wakeMode: "now",
+      payload: { kind: "systemEvent", text: "hello" },
+    });
+
+    await cron.run(job.id, "force");
+
+    expect(runHeartbeatOnce).toHaveBeenCalledTimes(1);
+    expect(runHeartbeatOnce).toHaveBeenCalledWith(
+      expect.objectContaining({
+        reason: `cron:${job.id}`,
+        agentId: "ops",
+      }),
+    );
+    expect(requestHeartbeatNow).not.toHaveBeenCalled();
+    expect(enqueueSystemEvent).toHaveBeenCalledWith("hello", { agentId: "ops" });
+
+    cron.stop();
+    await store.cleanup();
+  });
+
   it("wakeMode now falls back to queued heartbeat when main lane stays busy", async () => {
     const store = await makeStorePath();
     const enqueueSystemEvent = vi.fn();
diff --git a/src/cron/service/state.ts b/src/cron/service/state.ts
index c51103f339..025da7b3fa 100644
--- a/src/cron/service/state.ts
+++ b/src/cron/service/state.ts
@@ -37,7 +37,7 @@ export type CronServiceDeps = {
   sessionStorePath?: string;
   enqueueSystemEvent: (text: string, opts?: { agentId?: string }) => void;
   requestHeartbeatNow: (opts?: { reason?: string }) => void;
-  runHeartbeatOnce?: (opts?: { reason?: string }) => Promise<HeartbeatRunResult>;
+  runHeartbeatOnce?: (opts?: { reason?: string; agentId?: string }) => Promise<HeartbeatRunResult>;
   runIsolatedAgentJob: (params: { job: CronJob; message: string }) => Promise<{
     status: "ok" | "error" | "skipped";
     summary?: string;
diff --git a/src/cron/service/timer.ts b/src/cron/service/timer.ts
index 3b446848a3..802ff63b70 100644
--- a/src/cron/service/timer.ts
+++ b/src/cron/service/timer.ts
@@ -440,7 +440,7 @@ async function executeJobCore(
 
       let heartbeatResult: HeartbeatRunResult;
       for (;;) {
-        heartbeatResult = await state.deps.runHeartbeatOnce({ reason });
+        heartbeatResult = await state.deps.runHeartbeatOnce({ reason, agentId: job.agentId });
         if (
           heartbeatResult.status !== "skipped" ||
           heartbeatResult.reason !== "requests-in-flight"
diff --git a/src/gateway/server-cron.ts b/src/gateway/server-cron.ts
index 10ce4200a6..07fd2831cb 100644
--- a/src/gateway/server-cron.ts
+++ b/src/gateway/server-cron.ts
@@ -69,9 +69,11 @@ export function buildGatewayCronService(params: {
     requestHeartbeatNow,
     runHeartbeatOnce: async (opts) => {
       const runtimeConfig = loadConfig();
+      const agentId = opts?.agentId ? resolveCronAgent(opts.agentId).agentId : undefined;
       return await runHeartbeatOnce({
         cfg: runtimeConfig,
         reason: opts?.reason,
+        agentId,
         deps: { ...params.deps, runtime: defaultRuntime },
       });
     },