diff --git a/changelog.d/fixes/7940-gemini-429-model-lockout.md b/changelog.d/fixes/7940-gemini-429-model-lockout.md
new file mode 100644
index 0000000000..cac486caf9
--- /dev/null
+++ b/changelog.d/fixes/7940-gemini-429-model-lockout.md
@@ -0,0 +1 @@
+- fix(sse): parse Gemini 429 RetryInfo.retryDelay / "please retry in Ns" so model lockout honors the short upstream hint instead of falling back to a ~19h until-midnight cooldown (#7940)
diff --git a/open-sse/services/accountFallback.ts b/open-sse/services/accountFallback.ts
index bd1dbabe66..7617e5054d 100644
--- a/open-sse/services/accountFallback.ts
+++ b/open-sse/services/accountFallback.ts
@@ -36,7 +36,11 @@ import { getCodexModelScope } from "../config/codexQuotaScopes.ts";
 import { getQuotaScopedModelForProvider } from "./antigravityQuotaFamily.ts";
 import { isRpdExhausted, isRpmExhausted } from "./geminiRateLimitTracker.ts";
 import { setConnectionRateLimitUntil } from "@/lib/db/providers";
-import { parseRetryHintFromJsonBody } from "./retryAfterJson.ts";
+import {
+  parseRetryHintFromJsonBody,
+  parseDelayString,
+  MAX_SHORT_RETRY_HINT_MS,
+} from "./retryAfterJson.ts";
 import {
   isSubscriptionQuotaText,
   buildSubscriptionQuotaFallback,
@@ -1036,24 +1040,8 @@ export function parseRetryAfterFromBody(responseBody: unknown): {
   return { retryAfterMs: null, reason };
 }
 
-/**
- * Parse delay strings like "33s", "2m", "1h", "1500ms"
- */
-function parseDelayString(value: unknown): number | null {
-  if (!value) return null;
-  const str = String(value).trim();
-  const msMatch = /^(\d+)\s*ms$/i.exec(str);
-  if (msMatch) return Number.parseInt(msMatch[1], 10);
-  const secMatch = /^(\d+)\s*s$/i.exec(str);
-  if (secMatch) return Number.parseInt(secMatch[1], 10) * 1000;
-  const minMatch = /^(\d+)\s*m$/i.exec(str);
-  if (minMatch) return Number.parseInt(minMatch[1], 10) * 60 * 1000;
-  const hrMatch = /^(\d+)\s*h$/i.exec(str);
-  if (hrMatch) return Number.parseInt(hrMatch[1], 10) * 3600 * 1000;
-  // Bare number → seconds
-  const num = Number.parseInt(str, 10);
-  return Number.isNaN(num) ? null : num * 1000;
-}
+// parseDelayString now lives in ./retryAfterJson.ts (shared with parseRetryHintFromJsonBody's
+// Gemini RetryInfo.retryDelay parsing, #7940) — see the import at the top of this file.
 
 // T07: parse retry time from error text body with combined "XhYmZs" format.
 export function parseRetryFromErrorText(errorText: unknown): number | null {
@@ -1063,6 +1051,14 @@ export function parseRetryFromErrorText(errorText: unknown): number | null {
   const bodyHintMs = parseRetryHintFromJsonBody(msg, MAX_PROVIDER_COOLDOWN_MS);
   if (bodyHintMs !== null) return bodyHintMs;
 
+  // Gemini free-tier text fallback (no parseable JSON details present):
+  // "Please retry in 26.660853464s." Short throttle hint — capped independently of
+  // MAX_PROVIDER_COOLDOWN_MS, mirroring the JSON RetryInfo.retryDelay cap (#7940).
+  const pleaseRetryMs = parseDelayString(/please retry in\s+([\d.]+\s*s)/i.exec(msg)?.[1]);
+  if (pleaseRetryMs !== null && pleaseRetryMs > 0) {
+    return Math.min(pleaseRetryMs, MAX_SHORT_RETRY_HINT_MS);
+  }
+
   // Issue #2321: parse embedded absolute ISO retry timestamps.
   const isoMatch =
     /\b(?:try again at|wait until|reset(?:s)? at|available at|retry after)\s+(\d{4}-\d{2}-\d{2}[Tt ]\d{2}:\d{2}(?::\d{2})?(?:\.\d+)?(?:Z|[+-]\d{2}:?\d{2})?)/i.exec(
diff --git a/open-sse/services/retryAfterJson.ts b/open-sse/services/retryAfterJson.ts
index 1426fc3447..1c4b89f30a 100644
--- a/open-sse/services/retryAfterJson.ts
+++ b/open-sse/services/retryAfterJson.ts
@@ -18,6 +18,47 @@ function futureTimestampMs(value: unknown, maxMs: number): number | null {
   return waitMs > 0 ? Math.min(waitMs, maxMs) : null;
 }
 
+// RetryInfo.retryDelay / "please retry in Ns" are short per-request throttling
+// hints (Gemini free-tier RPM/TPM), not long-lived quota resets like Antigravity's
+// "Resets in 160h" — cap them independently of the caller's maxMs so a malformed or
+// adversarial upstream value cannot masquerade as a multi-day reset (#7940).
+export const MAX_SHORT_RETRY_HINT_MS = 24 * 60 * 60 * 1000; // 24h
+
+/**
+ * Parse delay strings like "33s", "26.660853464s", "2m", "1h", "1500ms", or a bare
+ * number of seconds. Shared by `parseRetryAfterFromBody` (rateLimitManager wiring)
+ * and `parseRetryHintFromJsonBody` (model-lockout wiring) so both honor the same
+ * upstream `RetryInfo.retryDelay` grammar (#7940).
+ */
+export function parseDelayString(value: unknown): number | null {
+  if (!value) return null;
+  const str = String(value).trim();
+  const msMatch = /^(\d+(?:\.\d+)?)\s*ms$/i.exec(str);
+  if (msMatch) return Math.round(Number.parseFloat(msMatch[1]));
+  const secMatch = /^(\d+(?:\.\d+)?)\s*s$/i.exec(str);
+  if (secMatch) return Math.round(Number.parseFloat(secMatch[1]) * 1000);
+  const minMatch = /^(\d+(?:\.\d+)?)\s*m$/i.exec(str);
+  if (minMatch) return Math.round(Number.parseFloat(minMatch[1]) * 60 * 1000);
+  const hrMatch = /^(\d+(?:\.\d+)?)\s*h$/i.exec(str);
+  if (hrMatch) return Math.round(Number.parseFloat(hrMatch[1]) * 3600 * 1000);
+  // Bare number → seconds
+  const num = Number.parseFloat(str);
+  return Number.isFinite(num) ? Math.round(num * 1000) : null;
+}
+
+// Gemini/Google RPC 429 bodies embed the short throttle hint as
+// `error.details[].{"@type": ".../google.rpc.RetryInfo", "retryDelay": "26s"}`.
+function retryInfoDetailsMs(details: unknown): number | null {
+  for (const detail of Array.isArray(details) ? details : []) {
+    const detailRecord = objectRecord(detail);
+    const type = String(detailRecord["@type"] ?? "");
+    if (!type.includes("RetryInfo")) continue;
+    const ms = parseDelayString(detailRecord.retryDelay);
+    if (ms !== null && ms > 0) return Math.min(ms, MAX_SHORT_RETRY_HINT_MS);
+  }
+  return null;
+}
+
 /**
  * Parse Retry-After hints from a 429 JSON response body. Providers use both
  * top-level and nested `error` fields for ISO timestamps and millisecond values.
@@ -34,6 +75,9 @@ export function parseRetryHintFromJsonBody(body: string, maxMs: number): number
   if (!Object.keys(root).length) return null;
   const errorObj = objectRecord(root.error);
 
+  const retryInfoMs = retryInfoDetailsMs(errorObj.details ?? root.details);
+  if (retryInfoMs !== null) return retryInfoMs;
+
   const isoHint = futureTimestampMs(errorObj.retryAfter ?? root.retryAfter, maxMs);
   if (isoHint !== null) return isoHint;
 
diff --git a/stryker.conf.json b/stryker.conf.json
index e93b99e852..4926210178 100644
--- a/stryker.conf.json
+++ b/stryker.conf.json
@@ -70,6 +70,7 @@
       "tests/unit/auto-combo-context-advertising.test.ts",
       "tests/unit/auto-combo-engine.test.ts",
       "tests/unit/auto-combo-scoring-clamp.test.ts",
+      "tests/unit/bug-7940-gemini-retrydelay.test.ts",
       "tests/unit/build/check-circular-deps.test.ts",
       "tests/unit/cache-sweeps.test.ts",
       "tests/unit/cc-bridge-openai-image-7777.test.ts",
diff --git a/tests/unit/bug-7940-gemini-retrydelay.test.ts b/tests/unit/bug-7940-gemini-retrydelay.test.ts
new file mode 100644
index 0000000000..c86cfdec37
--- /dev/null
+++ b/tests/unit/bug-7940-gemini-retrydelay.test.ts
@@ -0,0 +1,71 @@
+import { test } from "node:test";
+import assert from "node:assert/strict";
+import {
+  parseRetryFromErrorText,
+  recordModelLockoutFailure,
+  clearAllModelLockouts,
+  getModelLockoutInfo,
+} from "../../open-sse/services/accountFallback.ts";
+
+const GEMINI_429_BODY = JSON.stringify({
+  error: {
+    code: 429,
+    message:
+      "You exceeded your current quota, please check your plan and billing details. " +
+      "Please retry in 26.660853464s.",
+    status: "RESOURCE_EXHAUSTED",
+    details: [
+      {
+        "@type": "type.googleapis.com/google.rpc.QuotaFailure",
+        violations: [
+          { quotaMetric: "generativelanguage.googleapis.com/generate_content_free_tier_requests" },
+        ],
+      },
+      { "@type": "type.googleapis.com/google.rpc.RetryInfo", retryDelay: "26s" },
+    ],
+  },
+});
+
+test("parseRetryFromErrorText extracts Gemini RetryInfo.retryDelay (26s), not null", () => {
+  const parsedMs = parseRetryFromErrorText(GEMINI_429_BODY);
+  assert.notEqual(parsedMs, null, "expected the 26s RetryInfo hint to be parsed, got null");
+  assert.ok(parsedMs! >= 25_000 && parsedMs! <= 28_000, `expected ~26000ms, got ${parsedMs}ms`);
+});
+
+test("recordModelLockoutFailure quota_exhausted with a short upstream hint must NOT fall back to midnight", () => {
+  clearAllModelLockouts();
+  const provider = "gemini",
+    connectionId = "conn-7940",
+    model = "gemini-2.5-flash";
+  const quotaResetHintMs = parseRetryFromErrorText(GEMINI_429_BODY) ?? undefined;
+  const result = recordModelLockoutFailure(provider, connectionId, model, "quota_exhausted", 429, 0, null, {
+    exactCooldownMs: quotaResetHintMs ?? null,
+  });
+  const oneHourMs = 60 * 60 * 1000;
+  assert.ok(result.cooldownMs < oneHourMs, `expected ~26s cooldown, got ${result.cooldownMs}ms`);
+  clearAllModelLockouts();
+});
+
+test("parseRetryFromErrorText falls back to 'please retry in Ns' text when no JSON details are present", () => {
+  const plainText =
+    "429 RESOURCE_EXHAUSTED: You exceeded your current quota. Please retry in 12.5s.";
+  const parsedMs = parseRetryFromErrorText(plainText);
+  assert.notEqual(parsedMs, null, "expected the 12.5s text hint to be parsed, got null");
+  assert.ok(parsedMs! >= 12_000 && parsedMs! <= 13_500, `expected ~12500ms, got ${parsedMs}ms`);
+});
+
+test("getModelLockoutInfo reflects the short lockout, not a multi-hour one", () => {
+  clearAllModelLockouts();
+  const provider = "gemini",
+    connectionId = "conn-7940b",
+    model = "gemini-2.5-flash";
+  const quotaResetHintMs = parseRetryFromErrorText(GEMINI_429_BODY) ?? undefined;
+  recordModelLockoutFailure(provider, connectionId, model, "quota_exhausted", 429, 0, null, {
+    exactCooldownMs: quotaResetHintMs ?? null,
+  });
+  const info = getModelLockoutInfo(provider, connectionId, model);
+  assert.ok(info, "expected an active lockout entry");
+  const oneHourMs = 60 * 60 * 1000;
+  assert.ok(info!.remainingMs < oneHourMs, `expected <1h remaining, got ${info!.remainingMs}ms`);
+  clearAllModelLockouts();
+});