feat: update fingerprint versioning to match current runtime version

Author: NoeFabris

package.json

@@ -1,6 +1,6 @@
 {
     "name": "opencode-antigravity-auth",
-    "version": "1.5.4",
+    "version": "1.5.5",
     "description": "Google Antigravity IDE OAuth auth plugin for Opencode - access Gemini 3 Pro and Claude 4.6 using Google credentials",
     "main": "./dist/index.js",
     "types": "./dist/index.d.ts",

src/plugin/accounts.ts

@@ -3,7 +3,7 @@ import { loadAccounts, saveAccounts, type AccountStorageV4, type AccountMetadata
 import type { OAuthAuthDetails, RefreshParts } from "./types";
 import type { AccountSelectionStrategy } from "./config/schema";
 import { getHealthTracker, getTokenTracker, selectHybridAccount, type AccountWithMetrics } from "./rotation";
-import { generateFingerprint, type Fingerprint, type FingerprintVersion, MAX_FINGERPRINT_HISTORY } from "./fingerprint";
+import { generateFingerprint, updateFingerprintVersion, type Fingerprint, type FingerprintVersion, MAX_FINGERPRINT_HISTORY } from "./fingerprint";
 import type { QuotaGroup, QuotaGroupSummary } from "./quota";
 import { getModelFamily } from "./transform/model-resolver";
 import { debugLogToFile } from "./debug";
@@ -371,6 +371,16 @@ export class AccountManager {
         })
         .filter((a): a is ManagedAccount => a !== null);
 
+      // Update fingerprint versions to match the current runtime version.
+      // Saved fingerprints may carry an older version string; this ensures
+      // they always reflect the latest fetched (or fallback) version.
+      let fingerprintVersionChanged = false;
+      for (const acc of this.accounts) {
+        if (acc.fingerprint && updateFingerprintVersion(acc.fingerprint)) {
+          fingerprintVersionChanged = true;
+        }
+      }
+
       this.cursor = clampNonNegativeInt(stored.activeIndex, 0);
       if (this.accounts.length > 0) {
         this.cursor = this.cursor % this.accounts.length;
@@ -385,6 +395,11 @@ export class AccountManager {
         ) % this.accounts.length;
       }
 
+      // Persist updated fingerprint versions to disk
+      if (fingerprintVersionChanged) {
+        this.requestSaveToDisk();
+      }
+
       return;
     }
 

src/plugin/fingerprint.ts

@@ -137,6 +137,24 @@ export function collectCurrentFingerprint(): Fingerprint {
   };
 }
 
+/**
+ * Update the version in a fingerprint's userAgent to match the current runtime version.
+ * Called after version fetcher resolves so saved fingerprints always carry the latest version.
+ * Returns true if the userAgent was changed.
+ */
+export function updateFingerprintVersion(fingerprint: Fingerprint): boolean {
+  const currentVersion = getAntigravityVersion();
+  const versionPattern = /^(antigravity\/)([\d.]+)/;
+  const match = fingerprint.userAgent.match(versionPattern);
+
+  if (!match || match[2] === currentVersion) {
+    return false;
+  }
+
+  fingerprint.userAgent = fingerprint.userAgent.replace(versionPattern, `$1${currentVersion}`);
+  return true;
+}
+
 /**
  * Build HTTP headers from a fingerprint object.
  * These headers are used to identify the "device" making API requests.