diff --git a/contexthub/aidl/vts/VtsAidlHalContextHubTargetTest.cpp b/contexthub/aidl/vts/VtsAidlHalContextHubTargetTest.cpp
index 392e23c..a47f64e 100644
--- a/contexthub/aidl/vts/VtsAidlHalContextHubTargetTest.cpp
+++ b/contexthub/aidl/vts/VtsAidlHalContextHubTargetTest.cpp
@@ -103,15 +103,12 @@
 };
 
 TEST_P(ContextHubAidl, TestRegisterCallback) {
-    bool success;
     sp<EmptyContextHubCallback> cb = sp<EmptyContextHubCallback>::make();
-    ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb, &success).isOk());
-    ASSERT_TRUE(success);
+    ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb).isOk());
 }
 
 TEST_P(ContextHubAidl, TestRegisterNullCallback) {
-    bool success;
-    ASSERT_TRUE(contextHub->registerCallback(getHubId(), nullptr, &success).isOk());
+    ASSERT_TRUE(contextHub->registerCallback(getHubId(), nullptr).isOk());
 }
 
 // Helper callback that puts the async appInfo callback data into a promise
@@ -140,12 +137,8 @@
 // Calls queryApps() and checks the returned metadata
 TEST_P(ContextHubAidl, TestQueryApps) {
     sp<QueryAppsCallback> cb = sp<QueryAppsCallback>::make();
-    bool success;
-    ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb, &success).isOk());
-    ASSERT_TRUE(success);
-
-    ASSERT_TRUE(contextHub->queryNanoapps(getHubId(), &success).isOk());
-    ASSERT_TRUE(success);
+    ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb).isOk());
+    ASSERT_TRUE(contextHub->queryNanoapps(getHubId()).isOk());
 
     std::vector<NanoappInfo> appInfoList;
     ASSERT_TRUE(waitForCallback(cb->promise.get_future(), &appInfoList));
@@ -197,9 +190,7 @@
   public:
     virtual void SetUp() override {
         ContextHubAidl::SetUp();
-        bool success;
-        ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb, &success).isOk());
-        ASSERT_TRUE(success);
+        ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb).isOk());
     }
 
     sp<TransactionResultCallback> cb = sp<TransactionResultCallback>::make();
@@ -213,9 +204,7 @@
     std::fill(message.messageBody.begin(), message.messageBody.end(), 0);
 
     ALOGD("Sending message to non-existent nanoapp");
-    bool success;
-    ASSERT_TRUE(contextHub->sendMessageToHub(getHubId(), message, &success).isOk());
-    ASSERT_TRUE(success);
+    ASSERT_TRUE(contextHub->sendMessageToHub(getHubId(), message).isOk());
 }
 
 TEST_P(ContextHubTransactionTest, TestLoadEmptyNanoapp) {
@@ -229,9 +218,7 @@
     emptyApp.targetChreApiMinorVersion = 0;
 
     ALOGD("Loading empty nanoapp");
-    bool success;
-    ASSERT_TRUE(contextHub->loadNanoapp(getHubId(), emptyApp, cb->expectedTransactionId, &success)
-                        .isOk());
+    bool success = contextHub->loadNanoapp(getHubId(), emptyApp, cb->expectedTransactionId).isOk();
     if (success) {
         bool transactionSuccess;
         ASSERT_TRUE(waitForCallback(cb->promise.get_future(), &transactionSuccess));
@@ -243,11 +230,9 @@
     cb->expectedTransactionId = 1234;
 
     ALOGD("Unloading nonexistent nanoapp");
-    bool success;
-    ASSERT_TRUE(contextHub
-                        ->unloadNanoapp(getHubId(), kNonExistentAppId, cb->expectedTransactionId,
-                                        &success)
-                        .isOk());
+    bool success =
+            contextHub->unloadNanoapp(getHubId(), kNonExistentAppId, cb->expectedTransactionId)
+                    .isOk();
     if (success) {
         bool transactionSuccess;
         ASSERT_TRUE(waitForCallback(cb->promise.get_future(), &transactionSuccess));
@@ -259,11 +244,9 @@
     cb->expectedTransactionId = 2345;
 
     ALOGD("Enabling nonexistent nanoapp");
-    bool success;
-    ASSERT_TRUE(contextHub
-                        ->enableNanoapp(getHubId(), kNonExistentAppId, cb->expectedTransactionId,
-                                        &success)
-                        .isOk());
+    bool success =
+            contextHub->enableNanoapp(getHubId(), kNonExistentAppId, cb->expectedTransactionId)
+                    .isOk();
     if (success) {
         bool transactionSuccess;
         ASSERT_TRUE(waitForCallback(cb->promise.get_future(), &transactionSuccess));
@@ -275,11 +258,9 @@
     cb->expectedTransactionId = 3456;
 
     ALOGD("Disabling nonexistent nanoapp");
-    bool success;
-    ASSERT_TRUE(contextHub
-                        ->disableNanoapp(getHubId(), kNonExistentAppId, cb->expectedTransactionId,
-                                         &success)
-                        .isOk());
+    bool success =
+            contextHub->disableNanoapp(getHubId(), kNonExistentAppId, cb->expectedTransactionId)
+                    .isOk();
     if (success) {
         bool transactionSuccess;
         ASSERT_TRUE(waitForCallback(cb->promise.get_future(), &transactionSuccess));
@@ -290,16 +271,13 @@
 void ContextHubAidl::testSettingChanged(Setting setting) {
     // In VTS, we only test that sending the values doesn't cause things to blow up - GTS tests
     // verify the expected E2E behavior in CHRE
-    bool success;
     sp<EmptyContextHubCallback> cb = sp<EmptyContextHubCallback>::make();
-    ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb, &success).isOk());
-    ASSERT_TRUE(success);
+    ASSERT_TRUE(contextHub->registerCallback(getHubId(), cb).isOk());
 
     ASSERT_TRUE(contextHub->onSettingChanged(setting, true /* enabled */).isOk());
     ASSERT_TRUE(contextHub->onSettingChanged(setting, false /* enabled */).isOk());
 
-    ASSERT_TRUE(contextHub->registerCallback(getHubId(), nullptr, &success).isOk());
-    ASSERT_TRUE(success);
+    ASSERT_TRUE(contextHub->registerCallback(getHubId(), nullptr).isOk());
 }
 
 TEST_P(ContextHubAidl, TestOnLocationSettingChanged) {