diff --git a/AGENTS.MD b/AGENTS.MD
index f23d666..9f1b41f 100644
--- a/AGENTS.MD
+++ b/AGENTS.MD
@@ -118,7 +118,7 @@ Tool schemas are cleaned via allowlist. Unsupported fields (`const`, `$ref`, `$d
 Accounts rotate on rate limits. Gemini has dual quota pools (Antigravity headers + Gemini CLI headers). Fingerprints are per-account and regenerated on capacity exhaustion.
 
 ### 6. Fingerprint System
-Per-account device fingerprints stored in `antigravity-accounts.json`. Each fingerprint includes deviceId, sessionToken, userAgent, apiClient, clientMetadata. Headers: `User-Agent`, `X-Goog-Api-Client`, `Client-Metadata`, `X-Goog-QuotaUser`, `X-Client-Device-Id`. History tracked (max 5), restorable.
+Per-account device fingerprints stored in `antigravity-accounts.json`. Each fingerprint includes deviceId, sessionToken, userAgent, and a reduced clientMetadata (ideType, platform, pluginType — no osVersion, arch, or sqmId). The only header composed is `User-Agent`, built by `buildFingerprintHeaders()` in `fingerprint.ts` and applied on the antigravity request path in `request.ts`. History tracked (max 5), restorable.
 
 ## Dependencies
 
diff --git a/src/plugin.ts b/src/plugin.ts
index 340e0ed..a85e5fe 100644
--- a/src/plugin.ts
+++ b/src/plugin.ts
@@ -847,7 +847,7 @@ async function persistAccountPool(
     : (typeof stored?.activeIndex === "number" && Number.isFinite(stored.activeIndex) ? stored.activeIndex : 0);
 
   await saveAccounts({
-    version: 3,
+    version: 4,
     accounts,
     activeIndex: clampInt(activeIndex, 0, accounts.length - 1),
     activeIndexByFamily: {
@@ -2929,7 +2929,7 @@ export const createAntigravityPlugin = (providerId: string) => async (
                 );
                 // Use saveAccountsReplace to bypass merge (otherwise deleted account gets merged back)
                 await saveAccountsReplace({
-                  version: 3,
+                  version: 4,
                   accounts: updatedAccounts,
                   activeIndex: 0,
                   activeIndexByFamily: { claude: 0, gemini: 0 },
@@ -3145,7 +3145,7 @@ export const createAntigravityPlugin = (providerId: string) => async (
                         lastUsed: Date.now(),
                       };
                       await saveAccounts({
-                        version: 3,
+                        version: 4,
                         accounts: updatedAccounts,
                         activeIndex: currentStorage.activeIndex,
                         activeIndexByFamily: currentStorage.activeIndexByFamily,
diff --git a/src/plugin/accounts.test.ts b/src/plugin/accounts.test.ts
index 01bf561..24a02a5 100644
--- a/src/plugin/accounts.test.ts
+++ b/src/plugin/accounts.test.ts
@@ -1,7 +1,7 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
 
 import { AccountManager, type ModelFamily, type HeaderStyle, parseRateLimitReason, calculateBackoffMs, type RateLimitReason, resolveQuotaGroup } from "./accounts";
-import type { AccountStorageV3 } from "./storage";
+import type { AccountStorageV4 } from "./storage";
 import type { OAuthAuthDetails } from "./types";
 
 // Mock storage to prevent test data from leaking to real config files
@@ -28,8 +28,8 @@ describe("AccountManager", () => {
       expires: 123,
     };
 
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [],
       activeIndex: 0,
     };
@@ -39,8 +39,8 @@ describe("AccountManager", () => {
   });
 
   it("returns current account when not rate-limited for family", () => {
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -58,8 +58,8 @@ describe("AccountManager", () => {
   });
 
   it("switches to next account when current is rate-limited for family", () => {
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -78,8 +78,8 @@ describe("AccountManager", () => {
   });
 
   it("returns null when all accounts are rate-limited for family", () => {
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -101,8 +101,8 @@ describe("AccountManager", () => {
     vi.useFakeTimers();
     vi.setSystemTime(new Date(0));
 
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
       ],
@@ -123,8 +123,8 @@ describe("AccountManager", () => {
     vi.useFakeTimers();
     vi.setSystemTime(new Date(0));
 
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -143,8 +143,8 @@ describe("AccountManager", () => {
   });
 
   it("tracks rate limits per model family independently", () => {
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
       ],
@@ -172,8 +172,8 @@ describe("AccountManager", () => {
     vi.useFakeTimers();
     vi.setSystemTime(new Date(0));
 
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -206,8 +206,8 @@ describe("AccountManager", () => {
     vi.useFakeTimers();
     vi.setSystemTime(new Date(0));
 
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -237,8 +237,8 @@ describe("AccountManager", () => {
       expires: 123,
     };
 
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -259,8 +259,8 @@ describe("AccountManager", () => {
     vi.useFakeTimers();
     vi.setSystemTime(new Date(0));
 
-    const stored: AccountStorageV3 = {
-      version: 3,
+    const stored: AccountStorageV4 = {
+      version: 4,
       accounts: [
         { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
       ],
@@ -282,8 +282,8 @@ describe("AccountManager", () => {
 
   describe("header style fallback for Gemini", () => {
     it("tracks rate limits separately for each header style", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -300,8 +300,8 @@ describe("AccountManager", () => {
     });
 
     it("getAvailableHeaderStyle returns antigravity first for Gemini", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -315,8 +315,8 @@ describe("AccountManager", () => {
     });
 
     it("getAvailableHeaderStyle returns gemini-cli when antigravity is rate-limited", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -332,8 +332,8 @@ describe("AccountManager", () => {
     });
 
     it("getAvailableHeaderStyle returns null when both header styles are rate-limited", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -350,8 +350,8 @@ describe("AccountManager", () => {
     });
 
     it("getAvailableHeaderStyle always returns antigravity for Claude", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -365,8 +365,8 @@ describe("AccountManager", () => {
     });
 
     it("getAvailableHeaderStyle returns null for Claude when rate-limited", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -385,8 +385,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(0));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -411,8 +411,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(0));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -434,8 +434,8 @@ describe("AccountManager", () => {
 
   describe("per-family account tracking", () => {
     it("tracks current account independently per model family", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -458,8 +458,8 @@ describe("AccountManager", () => {
     });
 
     it("switching Claude account does not affect Gemini account selection", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -486,8 +486,8 @@ describe("AccountManager", () => {
     });
 
     it("persists per-family indices to storage", async () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -506,8 +506,8 @@ describe("AccountManager", () => {
     });
 
     it("loads per-family indices from storage", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -527,8 +527,8 @@ describe("AccountManager", () => {
     });
 
     it("falls back to activeIndex when activeIndexByFamily is not present", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -545,8 +545,8 @@ describe("AccountManager", () => {
 
   describe("account cooldown (non-429 errors)", () => {
     it("marks account as cooling down with reason", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -565,8 +565,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(0));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -586,8 +586,8 @@ describe("AccountManager", () => {
     });
 
     it("clearAccountCooldown removes cooldown state", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -605,8 +605,8 @@ describe("AccountManager", () => {
     });
 
     it("cooling down account is skipped in getCurrentOrNextForFamily", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -624,8 +624,8 @@ describe("AccountManager", () => {
     });
 
     it("cooldown is independent from rate limits", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -646,8 +646,8 @@ describe("AccountManager", () => {
   describe("account selection strategies", () => {
     describe("sticky strategy (default)", () => {
       it("returns same account on consecutive calls", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -667,8 +667,8 @@ describe("AccountManager", () => {
       });
 
       it("switches account only when current is rate-limited", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -690,8 +690,8 @@ describe("AccountManager", () => {
 
     describe("round-robin strategy", () => {
       it("rotates to next account on each call", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -712,8 +712,8 @@ describe("AccountManager", () => {
       });
 
       it("skips rate-limited accounts", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -736,8 +736,8 @@ describe("AccountManager", () => {
 
     describe("hybrid strategy", () => {
       it("returns fresh (untouched) accounts first", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -759,8 +759,8 @@ describe("AccountManager", () => {
       });
 
       it("continues to return valid accounts after all touched", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -785,8 +785,8 @@ describe("AccountManager", () => {
 
     describe("hybrid strategy with token bucket", () => {
       it("returns account based on health and token availability", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -803,8 +803,8 @@ describe("AccountManager", () => {
       });
 
       it("skips rate-limited accounts", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -821,8 +821,8 @@ describe("AccountManager", () => {
       });
 
       it("skips cooling down accounts", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -842,8 +842,8 @@ describe("AccountManager", () => {
         vi.useFakeTimers();
         vi.setSystemTime(new Date(0));
 
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           ],
@@ -860,8 +860,8 @@ describe("AccountManager", () => {
         vi.useFakeTimers();
         vi.setSystemTime(new Date(5000));
 
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
             { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -884,8 +884,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(1000));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -901,8 +901,8 @@ describe("AccountManager", () => {
     });
 
     it("isFreshForQuota returns true for untouched accounts", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -919,8 +919,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(1000));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -939,8 +939,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(1000));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -962,8 +962,8 @@ describe("AccountManager", () => {
 
   describe("consecutiveFailures tracking", () => {
     it("initializes consecutiveFailures as undefined", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -977,8 +977,8 @@ describe("AccountManager", () => {
     });
 
     it("can increment and reset consecutiveFailures", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1001,8 +1001,8 @@ describe("AccountManager", () => {
 
   describe("Issue #147: headerStyle-aware account selection", () => {
     it("skips account when requested headerStyle is rate-limited even if other style is available", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -1037,8 +1037,8 @@ describe("AccountManager", () => {
     });
 
     it("returns same account when a different headerStyle is rate-limited", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -1070,8 +1070,8 @@ describe("AccountManager", () => {
     it("requestSaveToDisk coalesces multiple calls into one write", async () => {
       vi.useFakeTimers();
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1097,8 +1097,8 @@ describe("AccountManager", () => {
     it("flushSaveToDisk waits for pending save to complete", async () => {
       vi.useFakeTimers();
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1123,8 +1123,8 @@ describe("AccountManager", () => {
     it("does not save again if no new requestSaveToDisk after flush", async () => {
       vi.useFakeTimers();
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1152,8 +1152,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(0));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1248,8 +1248,8 @@ describe("AccountManager", () => {
         vi.useFakeTimers();
         vi.setSystemTime(1000);
 
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           ],
@@ -1284,8 +1284,8 @@ describe("AccountManager", () => {
         vi.useFakeTimers();
         vi.setSystemTime(1000);
 
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           ],
@@ -1306,8 +1306,8 @@ describe("AccountManager", () => {
 
     describe("markRequestSuccess", () => {
       it("resets consecutive failure counter", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           ],
@@ -1328,8 +1328,8 @@ describe("AccountManager", () => {
         vi.useFakeTimers();
         vi.setSystemTime(10_000);
 
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0, rateLimitResetTimes: { "gemini-antigravity": 11_500, "gemini-cli": 11_500 } },
           ],
@@ -1346,8 +1346,8 @@ describe("AccountManager", () => {
         vi.useFakeTimers();
         vi.setSystemTime(10_000);
 
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0, rateLimitResetTimes: { "gemini-antigravity": 15_000, "gemini-cli": 15_000 } },
           ],
@@ -1361,8 +1361,8 @@ describe("AccountManager", () => {
       });
 
       it("shouldTryOptimisticReset returns false when accounts are available", () => {
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           ],
@@ -1377,8 +1377,8 @@ describe("AccountManager", () => {
         vi.useFakeTimers();
         vi.setSystemTime(10_000);
 
-        const stored: AccountStorageV3 = {
-          version: 3,
+        const stored: AccountStorageV4 = {
+          version: 4,
           accounts: [
             { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0, rateLimitResetTimes: { "gemini-antigravity": 70_000, "gemini-cli": 80_000 } },
             { refreshToken: "r2", projectId: "p2", addedAt: 2, lastUsed: 0, rateLimitResetTimes: { "gemini-antigravity": 90_000 } },
@@ -1409,8 +1409,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(0));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1439,8 +1439,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(0));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1467,8 +1467,8 @@ describe("AccountManager", () => {
 
   describe("Fingerprint History", () => {
     it("regenerateAccountFingerprint saves old fingerprint to history", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1493,8 +1493,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(1000)); // Start at 1000 to avoid 0 being falsy
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1533,8 +1533,8 @@ describe("AccountManager", () => {
     });
 
     it("getAccountFingerprintHistory returns empty array for new account", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1548,8 +1548,8 @@ describe("AccountManager", () => {
     });
 
     it("limits fingerprint history to MAX_FINGERPRINT_HISTORY", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1570,8 +1570,8 @@ describe("AccountManager", () => {
 
   describe("soft quota threshold", () => {
     it("skips account over soft quota threshold in sticky mode", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 2, lastUsed: 0 },
@@ -1587,8 +1587,8 @@ describe("AccountManager", () => {
     });
 
     it("allows account under soft quota threshold", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1603,8 +1603,8 @@ describe("AccountManager", () => {
     });
 
     it("threshold of 100 disables soft quota protection", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1619,8 +1619,8 @@ describe("AccountManager", () => {
     });
 
     it("returns null when all accounts over threshold", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 2, lastUsed: 0 },
@@ -1637,8 +1637,8 @@ describe("AccountManager", () => {
     });
 
     it("skips account over threshold in round-robin mode", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 2, lastUsed: 0 },
@@ -1654,8 +1654,8 @@ describe("AccountManager", () => {
     });
 
     it("account without cached quota is not skipped", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1669,8 +1669,8 @@ describe("AccountManager", () => {
     });
 
     it("handles remainingFraction of 0 (fully exhausted)", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 2, lastUsed: 0 },
@@ -1689,8 +1689,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date(0));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1709,8 +1709,8 @@ describe("AccountManager", () => {
     });
 
     it("fails open when cachedQuotaUpdatedAt is missing", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1729,8 +1729,8 @@ describe("AccountManager", () => {
 
   describe("getMinWaitTimeForSoftQuota", () => {
     it("returns 0 when accounts are available (under threshold)", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1745,8 +1745,8 @@ describe("AccountManager", () => {
     });
 
     it("returns null when no resetTime available", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1764,8 +1764,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date("2026-01-28T10:00:00Z"));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1791,8 +1791,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date("2026-01-28T16:00:00Z"));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
         ],
@@ -1818,8 +1818,8 @@ describe("AccountManager", () => {
       vi.useFakeTimers();
       vi.setSystemTime(new Date("2026-01-28T10:00:00Z"));
 
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 2, lastUsed: 0 },
diff --git a/src/plugin/accounts.ts b/src/plugin/accounts.ts
index 01eed27..e86ed5f 100644
--- a/src/plugin/accounts.ts
+++ b/src/plugin/accounts.ts
@@ -1,5 +1,5 @@
 import { formatRefreshParts, parseRefreshParts } from "./auth";
-import { loadAccounts, saveAccounts, type AccountStorageV3, type AccountMetadataV3, type RateLimitStateV3, type ModelFamily, type HeaderStyle, type CooldownReason } from "./storage";
+import { loadAccounts, saveAccounts, type AccountStorageV4, type AccountMetadataV3, type RateLimitStateV3, type ModelFamily, type HeaderStyle, type CooldownReason } from "./storage";
 import type { OAuthAuthDetails, RefreshParts } from "./types";
 import type { AccountSelectionStrategy } from "./config/schema";
 import { getHealthTracker, getTokenTracker, selectHybridAccount, type AccountWithMetrics } from "./rotation";
@@ -318,7 +318,7 @@ export class AccountManager {
     return new AccountManager(authFallback, stored);
   }
 
-  constructor(authFallback?: OAuthAuthDetails, stored?: AccountStorageV3 | null) {
+  constructor(authFallback?: OAuthAuthDetails, stored?: AccountStorageV4 | null) {
     const authParts = authFallback ? parseRefreshParts(authFallback.refresh) : null;
 
     if (stored && stored.accounts.length === 0) {
@@ -359,8 +359,8 @@ export class AccountManager {
             coolingDownUntil: acc.coolingDownUntil,
             cooldownReason: acc.cooldownReason,
             touchedForQuota: {},
-            // Always regenerate fingerprint on load to pick up alignment changes
-            fingerprint: generateFingerprint(),
+            fingerprint: acc.fingerprint ?? generateFingerprint(),
+            fingerprintHistory: acc.fingerprintHistory ?? [],
             cachedQuota: acc.cachedQuota as Partial<Record<QuotaGroup, QuotaGroupSummary>> | undefined,
             cachedQuotaUpdatedAt: acc.cachedQuotaUpdatedAt,
             verificationRequired: acc.verificationRequired,
@@ -977,8 +977,8 @@ export class AccountManager {
     const claudeIndex = Math.max(0, this.currentAccountIndexByFamily.claude);
     const geminiIndex = Math.max(0, this.currentAccountIndexByFamily.gemini);
     
-    const storage: AccountStorageV3 = {
-      version: 3,
+    const storage: AccountStorageV4 = {
+      version: 4,
       accounts: this.accounts.map((a) => ({
         email: a.email,
         refreshToken: a.parts.refreshToken,
diff --git a/src/plugin/antigravity-first-fallback.test.ts b/src/plugin/antigravity-first-fallback.test.ts
index 0006eb9..917872e 100644
--- a/src/plugin/antigravity-first-fallback.test.ts
+++ b/src/plugin/antigravity-first-fallback.test.ts
@@ -1,7 +1,7 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
 
 import { AccountManager, type ModelFamily, type HeaderStyle } from "./accounts";
-import type { AccountStorageV3 } from "./storage";
+import type { AccountStorageV4 } from "./storage";
 
 /**
  * Test: Antigravity-first fallback logic
@@ -21,8 +21,8 @@ describe("Antigravity-first fallback", () => {
 
   describe("hasOtherAccountWithAntigravityAvailable", () => {
     it("returns true when another account has antigravity available", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -47,8 +47,8 @@ describe("Antigravity-first fallback", () => {
     });
 
     it("returns false when all other accounts are also rate-limited for antigravity", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -73,8 +73,8 @@ describe("Antigravity-first fallback", () => {
     });
 
     it("skips disabled accounts", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0, enabled: false },
@@ -99,8 +99,8 @@ describe("Antigravity-first fallback", () => {
     });
 
     it("skips cooling down accounts", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -126,8 +126,8 @@ describe("Antigravity-first fallback", () => {
     });
 
     it("works with model-specific rate limits", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -152,8 +152,8 @@ describe("Antigravity-first fallback", () => {
     });
 
     it("returns false for Claude family (no gemini-cli fallback)", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -177,8 +177,8 @@ describe("Antigravity-first fallback", () => {
 
   describe("Pre-check fallback logic", () => {
     it("should switch to account with antigravity rather than fall back to gemini-cli", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
@@ -211,8 +211,8 @@ describe("Antigravity-first fallback", () => {
     });
 
     it("should only fall back to gemini-cli when ALL accounts exhausted antigravity", () => {
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           { refreshToken: "r1", projectId: "p1", addedAt: 1, lastUsed: 0 },
           { refreshToken: "r2", projectId: "p2", addedAt: 1, lastUsed: 0 },
diff --git a/src/plugin/persist-account-pool.test.ts b/src/plugin/persist-account-pool.test.ts
index db0b539..b98c590 100644
--- a/src/plugin/persist-account-pool.test.ts
+++ b/src/plugin/persist-account-pool.test.ts
@@ -11,7 +11,7 @@
 import { describe, expect, it, vi, beforeEach, afterEach } from "vitest";
 import { promises as fs } from "node:fs";
 import * as storageModule from "./storage";
-import type { AccountStorageV3, AccountMetadataV3 } from "./storage";
+import type { AccountStorageV4, AccountMetadataV3 } from "./storage";
 
 vi.mock("proper-lockfile", () => ({
   default: {
@@ -46,9 +46,9 @@ function createMockAccount(overrides: Partial<AccountMetadataV3> = {}): AccountM
   };
 }
 
-function createMockStorage(accounts: AccountMetadataV3[], activeIndex = 0): AccountStorageV3 {
+function createMockStorage(accounts: AccountMetadataV3[], activeIndex = 0): AccountStorageV4 {
   return {
-    version: 3,
+    version: 4,
     accounts,
     activeIndex,
   };
@@ -83,7 +83,7 @@ describe("loadAccounts", () => {
       const result = await storageModule.loadAccounts();
 
       expect(result).not.toBeNull();
-      expect(result?.version).toBe(3);
+      expect(result?.version).toBe(4);
       expect(result?.accounts).toHaveLength(1);
     });
 
@@ -141,7 +141,7 @@ describe("loadAccounts", () => {
     });
 
     it("returns null on invalid storage format", async () => {
-      vi.mocked(fs.readFile).mockResolvedValue(JSON.stringify({ version: 3, notAccounts: [] }));
+      vi.mocked(fs.readFile).mockResolvedValue(JSON.stringify({ version: 4, notAccounts: [] }));
 
       const result = await storageModule.loadAccounts();
 
@@ -175,7 +175,7 @@ describe("loadAccounts", () => {
 
       const result = await storageModule.loadAccounts();
 
-      expect(result?.version).toBe(3);
+      expect(result?.version).toBe(4);
       expect(result?.accounts).toHaveLength(1);
     });
   });
@@ -197,7 +197,7 @@ describe("saveAccounts", () => {
     const writtenContent = vi.mocked(fs.writeFile).mock.calls[0]?.[1];
     expect(writtenContent).toBeDefined();
     const parsed = JSON.parse(writtenContent as string);
-    expect(parsed.version).toBe(3);
+    expect(parsed.version).toBe(4);
     expect(parsed.accounts).toHaveLength(1);
   });
 });
diff --git a/src/plugin/refresh-queue.test.ts b/src/plugin/refresh-queue.test.ts
index 8bae7a8..d87903f 100644
--- a/src/plugin/refresh-queue.test.ts
+++ b/src/plugin/refresh-queue.test.ts
@@ -1,7 +1,7 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
 import { ProactiveRefreshQueue } from "./refresh-queue";
 import { AccountManager } from "./accounts";
-import type { AccountStorageV3 } from "./storage";
+import type { AccountStorageV4 } from "./storage";
 import type { PluginClient } from "./types";
 
 // Mock PluginClient
@@ -22,8 +22,8 @@ describe("ProactiveRefreshQueue", () => {
   describe("getAccountsNeedingRefresh", () => {
     it("skips disabled accounts", () => {
       const now = Date.now();
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           {
             refreshToken: "r1",
@@ -75,8 +75,8 @@ describe("ProactiveRefreshQueue", () => {
 
     it("includes accounts with undefined enabled (default to enabled)", () => {
       const now = Date.now();
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           {
             refreshToken: "r1",
@@ -109,8 +109,8 @@ describe("ProactiveRefreshQueue", () => {
 
     it("skips expired accounts", () => {
       const now = Date.now();
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           {
             refreshToken: "r1",
@@ -142,8 +142,8 @@ describe("ProactiveRefreshQueue", () => {
 
     it("skips accounts that don't need refresh yet", () => {
       const now = Date.now();
-      const stored: AccountStorageV3 = {
-        version: 3,
+      const stored: AccountStorageV4 = {
+        version: 4,
         accounts: [
           {
             refreshToken: "r1",
diff --git a/src/plugin/storage.test.ts b/src/plugin/storage.test.ts
index e935764..e1c6f9e 100644
--- a/src/plugin/storage.test.ts
+++ b/src/plugin/storage.test.ts
@@ -373,7 +373,7 @@ describe("Storage Migration", () => {
       vi.clearAllMocks();
     });
 
-    it("migrates V2 storage on load and persists V3", async () => {
+    it("migrates V2 storage on load and persists V4", async () => {
       const v2Data = {
         version: 2,
         accounts: [
@@ -402,7 +402,7 @@ describe("Storage Migration", () => {
       const result = await loadAccounts();
 
       expect(result).not.toBeNull();
-      expect(result?.version).toBe(3);
+      expect(result?.version).toBe(4);
 
       const account = result?.accounts[0];
       if (!account) throw new Error("Account not found");
@@ -419,7 +419,7 @@ describe("Storage Migration", () => {
       if (!saveCall) throw new Error("saveAccounts was not called (tmp file not found)");
 
       const savedContent = JSON.parse(saveCall[1] as string);
-      expect(savedContent.version).toBe(3);
+      expect(savedContent.version).toBe(4);
       expect(savedContent.accounts[0].rateLimitResetTimes).toEqual({
         "gemini-antigravity": future,
       });
diff --git a/src/plugin/storage.ts b/src/plugin/storage.ts
index 7d42152..6dac278 100644
--- a/src/plugin/storage.ts
+++ b/src/plugin/storage.ts
@@ -193,6 +193,7 @@ export interface AccountMetadataV3 {
   cooldownReason?: CooldownReason;
   /** Per-account device fingerprint for rate limit mitigation */
   fingerprint?: import("./fingerprint").Fingerprint;
+  fingerprintHistory?: import("./fingerprint").FingerprintVersion[];
   /** Set when Google asks the user to verify this account before requests can continue. */
   verificationRequired?: boolean;
   verificationRequiredAt?: number;
@@ -213,7 +214,21 @@ export interface AccountStorageV3 {
   };
 }
 
-type AnyAccountStorage = AccountStorageV1 | AccountStorage | AccountStorageV3;
+export interface AccountStorageV4 {
+  version: 4;
+  accounts: AccountMetadataV3[];
+  activeIndex: number;
+  activeIndexByFamily?: {
+    claude?: number;
+    gemini?: number;
+  };
+}
+
+type AnyAccountStorage =
+  | AccountStorageV1
+  | AccountStorage
+  | AccountStorageV3
+  | AccountStorageV4;
 
 /**
  * Gets the legacy Windows config directory (%APPDATA%\opencode).
@@ -361,7 +376,7 @@ async function ensureFileExists(path: string): Promise<void> {
     await fs.mkdir(dirname(path), { recursive: true });
     await fs.writeFile(
       path,
-      JSON.stringify({ version: 3, accounts: [], activeIndex: 0 }, null, 2),
+      JSON.stringify({ version: 4, accounts: [], activeIndex: 0 }, null, 2),
       { encoding: "utf-8", mode: 0o600 },
     );
   }
@@ -385,9 +400,9 @@ async function withFileLock<T>(path: string, fn: () => Promise<T>): Promise<T> {
 }
 
 function mergeAccountStorage(
-  existing: AccountStorageV3,
-  incoming: AccountStorageV3,
-): AccountStorageV3 {
+  existing: AccountStorageV4,
+  incoming: AccountStorageV4,
+): AccountStorageV4 {
   const accountMap = new Map<string, AccountMetadataV3>();
 
   for (const acc of existing.accounts) {
@@ -419,7 +434,7 @@ function mergeAccountStorage(
   }
 
   return {
-    version: 3,
+    version: 4,
     accounts: Array.from(accountMap.values()),
     activeIndex: incoming.activeIndex,
     activeIndexByFamily: incoming.activeIndexByFamily,
@@ -558,7 +573,20 @@ export function migrateV2ToV3(v2: AccountStorage): AccountStorageV3 {
   };
 }
 
-export async function loadAccounts(): Promise<AccountStorageV3 | null> {
+export function migrateV3ToV4(v3: AccountStorageV3): AccountStorageV4 {
+  return {
+    version: 4,
+    accounts: v3.accounts.map((acc) => ({
+      ...acc,
+      fingerprint: undefined,
+      fingerprintHistory: undefined,
+    })),
+    activeIndex: v3.activeIndex,
+    activeIndexByFamily: v3.activeIndexByFamily,
+  };
+}
+
+export async function loadAccounts(): Promise<AccountStorageV4 | null> {
   try {
     const path = getStoragePath();
     // Ensure permissions are correct on load (fixes existing files)
@@ -572,32 +600,45 @@ export async function loadAccounts(): Promise<AccountStorageV3 | null> {
       return null;
     }
 
-    let storage: AccountStorageV3;
+    let storage: AccountStorageV4;
 
     if (data.version === 1) {
-      log.info("Migrating account storage from v1 to v3");
+      log.info("Migrating account storage from v1 to v4");
       const v2 = migrateV1ToV2(data);
-      storage = migrateV2ToV3(v2);
+      const v3 = migrateV2ToV3(v2);
+      storage = migrateV3ToV4(v3);
       try {
         await saveAccounts(storage);
-        log.info("Migration to v3 complete");
+        log.info("Migration to v4 complete");
       } catch (saveError) {
         log.warn("Failed to persist migrated storage", {
           error: String(saveError),
         });
       }
     } else if (data.version === 2) {
-      log.info("Migrating account storage from v2 to v3");
-      storage = migrateV2ToV3(data);
+      log.info("Migrating account storage from v2 to v4");
+      const v3 = migrateV2ToV3(data);
+      storage = migrateV3ToV4(v3);
       try {
         await saveAccounts(storage);
-        log.info("Migration to v3 complete");
+        log.info("Migration to v4 complete");
       } catch (saveError) {
         log.warn("Failed to persist migrated storage", {
           error: String(saveError),
         });
       }
     } else if (data.version === 3) {
+      log.info("Migrating account storage from v3 to v4");
+      storage = migrateV3ToV4(data);
+      try {
+        await saveAccounts(storage);
+        log.info("Migration to v4 complete");
+      } catch (saveError) {
+        log.warn("Failed to persist migrated storage", {
+          error: String(saveError),
+        });
+      }
+    } else if (data.version === 4) {
       storage = data;
     } else {
       log.warn("Unknown storage version, ignoring", {
@@ -634,7 +675,7 @@ export async function loadAccounts(): Promise<AccountStorageV3 | null> {
     }
 
     return {
-      version: 3,
+      version: 4,
       accounts: deduplicatedAccounts,
       activeIndex,
     };
@@ -648,7 +689,7 @@ export async function loadAccounts(): Promise<AccountStorageV3 | null> {
   }
 }
 
-export async function saveAccounts(storage: AccountStorageV3): Promise<void> {
+export async function saveAccounts(storage: AccountStorageV4): Promise<void> {
   const path = getStoragePath();
   const configDir = dirname(path);
   await fs.mkdir(configDir, { recursive: true });
@@ -681,7 +722,7 @@ export async function saveAccounts(storage: AccountStorageV3): Promise<void> {
  * Use this for destructive operations like delete where we need to
  * remove accounts that would otherwise be merged back from existing storage.
  */
-export async function saveAccountsReplace(storage: AccountStorageV3): Promise<void> {
+export async function saveAccountsReplace(storage: AccountStorageV4): Promise<void> {
   const path = getStoragePath();
   const configDir = dirname(path);
   await fs.mkdir(configDir, { recursive: true });
@@ -705,7 +746,7 @@ export async function saveAccountsReplace(storage: AccountStorageV3): Promise<vo
   });
 }
 
-async function loadAccountsUnsafe(): Promise<AccountStorageV3 | null> {
+async function loadAccountsUnsafe(): Promise<AccountStorageV4 | null> {
   try {
     const path = getStoragePath();
     // Ensure permissions are correct on load (fixes existing files)
@@ -715,10 +756,13 @@ async function loadAccountsUnsafe(): Promise<AccountStorageV3 | null> {
     const parsed = JSON.parse(content);
 
     if (parsed.version === 1) {
-      return migrateV2ToV3(migrateV1ToV2(parsed));
+      return migrateV3ToV4(migrateV2ToV3(migrateV1ToV2(parsed)));
     }
     if (parsed.version === 2) {
-      return migrateV2ToV3(parsed);
+      return migrateV3ToV4(migrateV2ToV3(parsed));
+    }
+    if (parsed.version === 3) {
+      return migrateV3ToV4(parsed);
     }
 
     return {