fix: keep readiness confirmation responsive near its deadline

Co-Authored-By: Paperclip <noreply@paperclip.ing>

packages/paperclip-runner/src/live/warm-attachment-readiness.test.ts

@@ -46,5 +46,21 @@ it("does not reset the probe budget when readiness alternates", async () => {
     .then(() => "unexpected-ready", error => String(error));
   await vi.advanceTimersByTimeAsync(122_000);
   expect(await result).toContain("native_runner_warm_attachment_not_quiescent");
-  expect(calls).toBeLessThan(250);
+  expect(calls).toBeLessThan(350);
+});
+
+it("confirms readiness near the deadline after one unsettled observation", async () => {
+  vi.useFakeTimers();
+  vi.setSystemTime(0);
+  let recoveredProbes = 0;
+  const result = waitForWarmAttachmentReadiness({
+    graceMs: 5_000,
+    waitForConnection: async () => {},
+    snapshot: async () => ({
+      warmAttachReady: Date.now() >= 4_400 && ++recoveredProbes !== 2,
+      warmAttachBlockers: [],
+    }),
+  }).then(() => "ready", error => String(error));
+  await vi.advanceTimersByTimeAsync(5_000);
+  expect(await result).toBe("ready");
 });

packages/paperclip-runner/src/live/warm-attachment-readiness.ts

@@ -8,13 +8,17 @@ export async function waitForWarmAttachmentReadiness(input: {
   const deadline = Date.now() + input.graceMs;
   let consecutiveReadyProbes = 0;
   let lastBlockers: unknown = null;
-  let blockedDelayMs = 25;
+  let probes = 0;
   // Each probe is a durable command. A 25 ms loop over the remote 120 second
   // reconnect budget can exhaust its 500-command journal before that budget.
-  const maxBlockedDelayMs = Math.max(1_000, Math.ceil(input.graceMs / 100));
+  // Leave room for both ready-confirmation probes and ordinary commands. The
+  // interval is proportional to the deadline, so a short local deadline never
+  // inherits a one-second delay after a transient readiness regression.
+  const blockedDelayMs = Math.max(25, Math.ceil(input.graceMs / 160));
   while (Date.now() < deadline) {
     await input.waitForConnection(deadline);
     const snapshot = await input.snapshot(deadline);
+    probes += 1;
     if (snapshot.warmAttachReady !== true && JSON.stringify(snapshot.warmAttachBlockers) !== JSON.stringify(lastBlockers)) {
       input.onBlocked?.(snapshot.warmAttachBlockers);
     }
@@ -25,8 +29,7 @@ export async function waitForWarmAttachmentReadiness(input: {
     } else {
       consecutiveReadyProbes = 0;
     }
-    const delayMs = snapshot.warmAttachReady === true ? 25 : blockedDelayMs;
-    if (snapshot.warmAttachReady !== true) blockedDelayMs = Math.min(blockedDelayMs * 2, maxBlockedDelayMs);
+    const delayMs = snapshot.warmAttachReady === true || probes < 8 ? 25 : blockedDelayMs;
     await new Promise<void>(resolve => setTimeout(resolve, Math.min(delayMs, Math.max(0, deadline - Date.now()))));
   }
   throw new Error(`native_runner_warm_attachment_not_quiescent: ${JSON.stringify(lastBlockers)}`);