From bfd2d5603cecaa36ec78cd1f240c11fe1ca46354 Mon Sep 17 00:00:00 2001
From: Diego Rodrigues de Sa e Souza <diegosouza.pw@gmail.com>
Date: Wed, 5 Aug 2026 22:40:33 -0300
Subject: [PATCH] fix(codex): preserve quota window duration (#9222)
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Validated in local merge-train (devbox-vm-06-dev002) @ combined-tip (FAST gates — only pre-existing audit.test.ts flake).
---
 .../fixes/9222-codex-quota-window-duration.md |  1 +
 open-sse/services/codexUsageQuotas.ts         | 28 ++++++++--
 tests/unit/codex-usage-windows.test.ts        | 52 +++++++++++++++++++
 3 files changed, 76 insertions(+), 5 deletions(-)
 create mode 100644 changelog.d/fixes/9222-codex-quota-window-duration.md
 create mode 100644 tests/unit/codex-usage-windows.test.ts

diff --git a/changelog.d/fixes/9222-codex-quota-window-duration.md b/changelog.d/fixes/9222-codex-quota-window-duration.md
new file mode 100644
index 0000000000..2f2e7dd2b7
--- /dev/null
+++ b/changelog.d/fixes/9222-codex-quota-window-duration.md
@@ -0,0 +1 @@
+- **fix(codex):** preserve quota window duration in usage shape. (thanks @HectorBernstorff)
diff --git a/open-sse/services/codexUsageQuotas.ts b/open-sse/services/codexUsageQuotas.ts
index 4d4ed9c229..e730e9279d 100644
--- a/open-sse/services/codexUsageQuotas.ts
+++ b/open-sse/services/codexUsageQuotas.ts
@@ -13,6 +13,7 @@ export type CodexUsageQuota = {
   remaining?: number;
   resetAt: string | null;
   unlimited: boolean;
+  windowSeconds: number | null;
   displayName?: string;
 };
 
@@ -38,6 +39,15 @@ function toNumber(value: unknown, fallback = 0): number {
   return fallback;
 }
 
+function toNullableNumber(value: unknown): number | null {
+  if (typeof value === "number" && Number.isFinite(value)) return value;
+  if (typeof value === "string" && value.trim().length > 0) {
+    const parsed = Number(value);
+    return Number.isFinite(parsed) ? parsed : null;
+  }
+  return null;
+}
+
 function parseResetTime(resetValue: unknown): string | null {
   if (!resetValue) return null;
   try {
@@ -81,6 +91,15 @@ function buildPercentageQuota(window: JsonRecord, displayName?: string): CodexUs
     remaining: 100 - usedPercent,
     resetAt: parseWindowReset(window),
     unlimited: false,
+    windowSeconds: toNullableNumber(
+      getFieldValue(
+        window,
+        "limit_window_seconds",
+        "limitWindowSeconds",
+        "window_seconds",
+        "windowSeconds"
+      )
+    ),
     ...(displayName ? { displayName } : {}),
   };
 }
@@ -105,10 +124,7 @@ function isLatentWindow(window: JsonRecord): boolean {
     getFieldValue(window, "limit_window_seconds", "limitWindowSeconds"),
     0
   );
-  const resetAfter = toNumber(
-    getFieldValue(window, "reset_after_seconds", "resetAfterSeconds"),
-    0
-  );
+  const resetAfter = toNumber(getFieldValue(window, "reset_after_seconds", "resetAfterSeconds"), 0);
   return usedPercent === 0 && limitWindow > 0 && resetAfter >= limitWindow;
 }
 
@@ -225,7 +241,9 @@ function findCodexReviewRateLimit(data: JsonRecord): JsonRecord {
  * (issue #5199).
  */
 function parseBankedResetCredits(data: JsonRecord): number | undefined {
-  const resetCredits = toRecord(getFieldValue(data, "rate_limit_reset_credits", "rateLimitResetCredits"));
+  const resetCredits = toRecord(
+    getFieldValue(data, "rate_limit_reset_credits", "rateLimitResetCredits")
+  );
   const availableCount = getFieldValue(resetCredits, "available_count", "availableCount");
   const count = toNumber(availableCount, NaN);
   return Number.isFinite(count) ? count : undefined;
diff --git a/tests/unit/codex-usage-windows.test.ts b/tests/unit/codex-usage-windows.test.ts
new file mode 100644
index 0000000000..e45c51c562
--- /dev/null
+++ b/tests/unit/codex-usage-windows.test.ts
@@ -0,0 +1,52 @@
+import assert from "node:assert/strict";
+import { describe, it } from "node:test";
+
+import { buildCodexUsageQuotas } from "../../open-sse/services/codexUsageQuotas";
+
+describe("Codex usage windows", () => {
+  it("preserves upstream durations for session and weekly windows", () => {
+    const { quotas } = buildCodexUsageQuotas({
+      rate_limit: {
+        primary_window: {
+          used_percent: 7,
+          limit_window_seconds: 18_000,
+          reset_at: 1_785_623_016,
+        },
+        secondary_window: {
+          used_percent: 19,
+          limit_window_seconds: 604_800,
+          reset_at: 1_785_678_428,
+        },
+      },
+    });
+
+    assert.deepEqual(quotas.session, {
+      used: 7,
+      total: 100,
+      remaining: 93,
+      resetAt: new Date(1_785_623_016_000).toISOString(),
+      unlimited: false,
+      windowSeconds: 18_000,
+    });
+    assert.deepEqual(quotas.weekly, {
+      used: 19,
+      total: 100,
+      remaining: 81,
+      resetAt: new Date(1_785_678_428_000).toISOString(),
+      unlimited: false,
+      windowSeconds: 604_800,
+    });
+  });
+
+  it("accepts camelCase duration variants and nulls invalid values", () => {
+    const { quotas } = buildCodexUsageQuotas({
+      rateLimit: {
+        primaryWindow: { usedPercent: 3, windowSeconds: "18000" },
+        secondaryWindow: { usedPercent: 4, windowSeconds: "not-a-number" },
+      },
+    });
+
+    assert.equal(quotas.session.windowSeconds, 18_000);
+    assert.equal(quotas.weekly.windowSeconds, null);
+  });
+});