[WRONG BRANCH] fix(codex): honor scoped cooldowns in subagent fallback

src/codex/routing.ts

@@ -589,6 +589,15 @@ export function tryAcquireCodexQuotaScopeProbeLease(
   return probeLeaseId;
 }
 
+/** Side-effect-free check for a confirmed model-specific quota probe. */
+export function canAcquireCodexQuotaScopeProbeLease(
+  accountId: string,
+  scope: CodexQuotaScope,
+  now = Date.now(),
+): boolean {
+  return canAcquireQuotaProbeLease(scopedHealthFor(accountId, scope), now);
+}
+
 /**
  * Hand a probe lease back without recording an upstream outcome. Used by paths
  * that take a lease and then fail before any request reaches upstream.

src/codex/subagent-model-fallback.ts

@@ -15,11 +15,11 @@ import { CODEX_HOME, getCodexHome } from "./paths";
 import { CODEX_UNKNOWN_USAGE_SCORE, getAccountQuota } from "./quota";
 import {
   canAcquireCodexQuotaProbeLease,
+  canAcquireCodexQuotaScopeProbeLease,
   codexQuotaScopeForModel,
   computeCodexUsageScore,
   getCodexQuotaHealthSnapshot,
   getPoolAccountPlan,
-  isCodexAccountInCooldown,
 } from "./routing";
 import {
   isCodexAccountUsable,
@@ -233,11 +233,15 @@ export function isSubagentModelUnavailable(
     // advances instead of selecting a candidate that exact auth will reject.
     const quotaScope = codexQuotaScopeForModel(route.modelId);
     if (getCodexQuotaHealthSnapshot(resolvedAccountId, quotaScope, now) !== null) return true;
-  } else if (
-    isCodexAccountInCooldown(resolvedAccountId, now)
-    && !canAcquireCodexQuotaProbeLease(resolvedAccountId, now)
-  ) {
-    return true;
+  } else {
+    const quotaScope = codexQuotaScopeForModel(route.modelId);
+    const cooldown = getCodexQuotaHealthSnapshot(resolvedAccountId, quotaScope, now);
+    if (cooldown !== null) {
+      const probeAvailable = cooldown.quotaScope
+        ? canAcquireCodexQuotaScopeProbeLease(resolvedAccountId, cooldown.quotaScope, now)
+        : canAcquireCodexQuotaProbeLease(resolvedAccountId, now);
+      if (!probeAvailable) return true;
+    }
   }
   return isNativeModelQuotaExhausted(model, config, accountId, now);
 }

tests/subagent-model-fallback.test.ts

@@ -295,6 +295,23 @@ describe("subagent model fallback chain", () => {
     });
   });
 
+  test("pool fallback skips a reset-derived cooldown in the model's quota scope", () => {
+    const now = 1_800_000_000_000;
+    updateAccountQuota("pool-a", 10, undefined, 20);
+    const config = cfg({ subagentModelFallback: ["kimi/k3"] });
+    recordCodexUpstreamOutcome(config, "pool-a", 429, {
+      modelId: "gpt-5.6-sol",
+      now,
+      resetAt: Math.floor((now + 60 * 60_000) / 1_000),
+    });
+
+    expect(selectAvailableSubagentModel("gpt-5.6-sol", config, [], "pool-a", now + 1)).toEqual({
+      model: "kimi/k3",
+      rewritten: true,
+      skipped: ["gpt-5.6-sol"],
+    });
+  });
+
   test("account selector fallbacks still reject invalid or disabled native models", () => {
     resetSubagentModelFallbackStateForTests();
     updateAccountQuota("pool-a", 95, undefined, 20);