diff --git a/packages/runtime-host/src/__tests__/event-wait-manager.test.ts b/packages/runtime-host/src/__tests__/event-wait-manager.test.ts
index a420ccff8dc..57c3daa0122 100644
--- a/packages/runtime-host/src/__tests__/event-wait-manager.test.ts
+++ b/packages/runtime-host/src/__tests__/event-wait-manager.test.ts
@@ -22,6 +22,7 @@ import { mkdtemp, rm, readFile } from 'node:fs/promises';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
 import { test, type TestContext } from 'node:test';
+import { setTimeout as delay } from 'node:timers/promises';
 import {
   EVENT_WAIT_LIMITS,
   eventWaitDeliveryKey,
@@ -55,9 +56,12 @@ async function settle() {
   for (let n = 0; n < 40; n++) await new Promise<void>((resolve) => setImmediate(resolve));
 }
 async function eventually(check: () => Promise<boolean> | boolean) {
-  for (let n = 0; n < 100; n++) {
+  // Host I/O needs wall-clock time; immediate turns can exhaust before it completes.
+  // Keep the injected observation clock fixed so timeout/Retry-After assertions remain exact.
+  const deadline = performance.now() + 5_000;
+  while (performance.now() < deadline) {
     if (await check()) return;
-    await settle();
+    await delay(5);
   }
   assert.fail('Condition did not settle without advancing the observation clock');
 }
@@ -94,6 +98,26 @@ class Clock implements EventWaitClock {
     await settle();
   }
 }
+test('eventually waits for delayed host work without advancing the observation clock', async () => {
+  const clock = new Clock();
+  let observationTimerRan = false;
+  clock.schedule(() => {
+    observationTimerRan = true;
+  }, 1);
+  let completed = false;
+  const work = delay(200).then(() => {
+    completed = true;
+  });
+  try {
+    await eventually(() => completed);
+    assert.equal(clock.now(), 1_000);
+    assert.equal(observationTimerRan, false);
+    assert.equal(clock.timers.size, 1);
+  } finally {
+    await work;
+  }
+});
+
 const satisfied = (key = 'event-1'): EventWaitObservationResult => ({
   kind: 'satisfied',
   receiptKey: key,