diff --git a/packages/gateway-protocol/src/connect-error-details.test.ts b/packages/gateway-protocol/src/connect-error-details.test.ts
index 1cdb3a3bd3f4..377fcee42cde 100644
--- a/packages/gateway-protocol/src/connect-error-details.test.ts
+++ b/packages/gateway-protocol/src/connect-error-details.test.ts
@@ -11,7 +11,7 @@ import {
   formatConnectPairingRequiredMessage,
   normalizePairingConnectRequestId,
   readConnectErrorDetailCode,
-  readControlUiBuildMismatchDetails,
+  readControlUiBuildMismatchId,
   readConnectErrorRecoveryAdvice,
   readConnectPairingRequiredMessage,
   readPairingConnectErrorDetails,
@@ -44,19 +44,15 @@ describe("readConnectErrorDetailCode", () => {
   });
 });
 
-describe("readControlUiBuildMismatchDetails", () => {
+describe("readControlUiBuildMismatchId", () => {
   it("returns a bounded reload target", () => {
     expect(
-      readControlUiBuildMismatchDetails({
+      readControlUiBuildMismatchId({
         code: ConnectErrorDetailCodes.CONTROL_UI_BUILD_MISMATCH,
         gatewayBuildId: "gateway-build",
         reloadRequired: true,
       }),
-    ).toEqual({
-      code: ConnectErrorDetailCodes.CONTROL_UI_BUILD_MISMATCH,
-      gatewayBuildId: "gateway-build",
-      reloadRequired: true,
-    });
+    ).toBe("gateway-build");
   });
 
   it.each([
@@ -73,7 +69,7 @@ describe("readControlUiBuildMismatchDetails", () => {
       reloadRequired: false,
     },
   ])("rejects malformed details", (details) => {
-    expect(readControlUiBuildMismatchDetails(details)).toBeNull();
+    expect(readControlUiBuildMismatchId(details)).toBeNull();
   });
 });
 
diff --git a/packages/gateway-protocol/src/connect-error-details.ts b/packages/gateway-protocol/src/connect-error-details.ts
index f9221ee6ceb7..04ba3b1cf0c1 100644
--- a/packages/gateway-protocol/src/connect-error-details.ts
+++ b/packages/gateway-protocol/src/connect-error-details.ts
@@ -55,12 +55,6 @@ export const ConnectErrorDetailCodes = {
 type ConnectErrorDetailCode =
   (typeof ConnectErrorDetailCodes)[keyof typeof ConnectErrorDetailCodes];
 
-export type ControlUiBuildMismatchDetails = {
-  code: typeof ConnectErrorDetailCodes.CONTROL_UI_BUILD_MISMATCH;
-  gatewayBuildId: string;
-  reloadRequired: true;
-};
-
 /** Pairing-specific reasons clients can display and use for reconnect policy. */
 const ConnectPairingRequiredReasons = {
   NOT_PAIRED: "not-paired",
@@ -237,15 +231,8 @@ export function readConnectErrorDetailCode(details: unknown): string | null {
 }
 
 /** Read the exact target artifact from an untrusted reload-required rejection. */
-export function readControlUiBuildMismatchDetails(
-  details: unknown,
-): ControlUiBuildMismatchDetails | null {
-  if (
-    readConnectErrorDetailCode(details) !== ConnectErrorDetailCodes.CONTROL_UI_BUILD_MISMATCH ||
-    !details ||
-    typeof details !== "object" ||
-    Array.isArray(details)
-  ) {
+export function readControlUiBuildMismatchId(details: unknown): string | null {
+  if (readConnectErrorDetailCode(details) !== ConnectErrorDetailCodes.CONTROL_UI_BUILD_MISMATCH) {
     return null;
   }
   const raw = details as { gatewayBuildId?: unknown; reloadRequired?: unknown };
@@ -253,11 +240,7 @@ export function readControlUiBuildMismatchDetails(
   if (!gatewayBuildId || gatewayBuildId.length > 96 || raw.reloadRequired !== true) {
     return null;
   }
-  return {
-    code: ConnectErrorDetailCodes.CONTROL_UI_BUILD_MISMATCH,
-    gatewayBuildId,
-    reloadRequired: true,
-  };
+  return gatewayBuildId;
 }
 
 /** Extracts normalized retry advice from untrusted connect-error details. */
diff --git a/ui/src/api/gateway-connect-errors.ts b/ui/src/api/gateway-connect-errors.ts
index a765f3afd430..354f82ef4b06 100644
--- a/ui/src/api/gateway-connect-errors.ts
+++ b/ui/src/api/gateway-connect-errors.ts
@@ -1,10 +1,8 @@
 import {
   ConnectErrorDetailCodes,
-  GatewayProtocolRequestError,
   MIN_CLIENT_PROTOCOL_VERSION,
   PROTOCOL_VERSION,
   readConnectErrorDetailCode,
-  shouldPauseGatewayReconnect,
 } from "@openclaw/gateway-client/browser";
 
 export function enrichProtocolMismatchDetails(
@@ -30,22 +28,3 @@ export function resolveGatewayErrorDetailCode(
 ): string | null {
   return readConnectErrorDetailCode(error?.details);
 }
-
-export function isLegacyGatewayBuildIdSchemaError(
-  error: GatewayProtocolRequestError,
-  clientBuildId: string | undefined,
-): boolean {
-  return Boolean(
-    clientBuildId && /invalid connect params.*unexpected property.*buildid/iu.test(error.message),
-  );
-}
-
-/** Token mismatch stays with its bounded retry owner; static failures pause. */
-export function isNonRecoverableConnectError(error: { details?: unknown } | undefined): boolean {
-  return error
-    ? shouldPauseGatewayReconnect({
-        details: error.details,
-        protocolMismatchIsTerminal: true,
-      })
-    : false;
-}
diff --git a/ui/src/api/gateway.ts b/ui/src/api/gateway.ts
index ed318bc1e0ec..27f75422f6a6 100644
--- a/ui/src/api/gateway.ts
+++ b/ui/src/api/gateway.ts
@@ -27,6 +27,7 @@ import {
   PROTOCOL_VERSION,
   resolveGatewayStartupRetryAfterMs,
   resolveSafeTimeoutDelayMs,
+  shouldPauseGatewayReconnect,
 } from "@openclaw/gateway-client/browser";
 export type { EventFrame as GatewayEventFrame } from "@openclaw/gateway-client/browser";
 import type {
@@ -54,8 +55,6 @@ import { generateUUID } from "../lib/uuid.ts";
 import { createBrowserGatewaySocket } from "./gateway-browser-socket.ts";
 import {
   enrichProtocolMismatchDetails,
-  isLegacyGatewayBuildIdSchemaError,
-  isNonRecoverableConnectError,
   resolveGatewayErrorDetailCode,
 } from "./gateway-connect-errors.ts";
 
@@ -288,7 +287,6 @@ export class GatewayBrowserClient {
   // Older shipped Gateways used a closed client schema. Downgrade once per
   // browser client; a document reload creates a fresh exact-identity attempt.
   private clientBuildIdCompatibilityDisabled = false;
-  private clientBuildIdRetryBudgetUsed = false;
   // Close/stop advances this generation before another socket can make stale hello work look active.
   private recovery = { value: "", resolved: false, generation: 0 };
   private scopeUpgradeBinding: ScopeUpgradeBinding | null = null;
@@ -380,7 +378,6 @@ export class GatewayBrowserClient {
     this.pendingDeviceTokenRetry = false;
     this.deviceTokenRetryBudgetUsed = false;
     this.clientBuildIdCompatibilityDisabled = false;
-    this.clientBuildIdRetryBudgetUsed = false;
   }
 
   get connected() {
@@ -587,11 +584,11 @@ export class GatewayBrowserClient {
     const connectErrorCode =
       err instanceof GatewayRequestError ? resolveGatewayErrorDetailCode(err) : null;
     if (
-      !this.clientBuildIdRetryBudgetUsed &&
-      isLegacyGatewayBuildIdSchemaError(err, plan.params.client.buildId)
+      !this.clientBuildIdCompatibilityDisabled &&
+      plan.params.client.buildId &&
+      /invalid connect params.*unexpected property.*buildid/iu.test(err.message)
     ) {
       this.clientBuildIdCompatibilityDisabled = true;
-      this.clientBuildIdRetryBudgetUsed = true;
       this.client.resetReconnectBackoff(250);
       return { closeCode: CONNECT_FAILED_CLOSE_CODE, closeReason: "connect retry" };
     }
@@ -725,7 +722,10 @@ export class GatewayBrowserClient {
     const retry =
       connectErrorCode === ConnectErrorDetailCodes.AUTH_TOKEN_MISMATCH
         ? this.pendingDeviceTokenRetry
-        : !isNonRecoverableConnectError(connectError);
+        : !shouldPauseGatewayReconnect({
+            details: connectError?.details,
+            protocolMismatchIsTerminal: true,
+          });
     return { retry, notify: true, pendingError: error };
   }
 
diff --git a/ui/src/app/gateway-store.ts b/ui/src/app/gateway-store.ts
index ccfa28dc24b3..7afc6245777c 100644
--- a/ui/src/app/gateway-store.ts
+++ b/ui/src/app/gateway-store.ts
@@ -1,4 +1,4 @@
-import { readControlUiBuildMismatchDetails } from "@openclaw/gateway-client/browser";
+import { readControlUiBuildMismatchId } from "@openclaw/gateway-client/browser";
 import type { ControlUiBootstrapProfileHint } from "../../../src/gateway/control-ui-contract.js";
 // Control UI module owns the application gateway store: the reactive
 // snapshot around GatewayBrowserClient consumed by the app shell.
@@ -431,9 +431,9 @@ export function createApplicationGateway(
           return;
         }
         stopCanvasSurfaceLease();
-        const buildMismatch = readControlUiBuildMismatchDetails(error?.details);
-        if (buildMismatch) {
-          void scheduleStaleChunkReload({ buildId: buildMismatch.gatewayBuildId });
+        const mismatchedBuildId = readControlUiBuildMismatchId(error?.details);
+        if (mismatchedBuildId) {
+          void scheduleStaleChunkReload({ buildId: mismatchedBuildId });
         }
         setSnapshot({
           ...snapshot,