diff --git a/tests/nexus/test_1_3_GEN_TC_2.cpp b/tests/nexus/test_1_3_GEN_TC_2.cpp
index 6f253b7bf..9189a595f 100644
--- a/tests/nexus/test_1_3_GEN_TC_2.cpp
+++ b/tests/nexus/test_1_3_GEN_TC_2.cpp
@@ -176,6 +176,8 @@ void Test_1_3_GEN_TC_2(const char *aJsonFileName)
          */
         Log("Step 2: Eth_1 sends mDNS PTR query for _meshcop._udp.local.");
         Dns::Multicast::Core::Browser browser;
+
+        ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const Dns::Multicast::Core::BrowseResult *) {};
         browser.mServiceType  = kMeshCoPServiceType;
         browser.mInfraIfIndex = kInfraIfIndex;
@@ -202,6 +204,7 @@ void Test_1_3_GEN_TC_2(const char *aJsonFileName)
             Dns::Multicast::Core::TxtResolver resolver;
             char                              serviceInstance[64];
 
+            ClearAllBytes(resolver);
             snprintf(serviceInstance, sizeof(serviceInstance), "OpenThread%s",
                      br1.Get<Mac::Mac>().GetExtAddress().ToString().AsCString());
 
diff --git a/tests/nexus/test_1_3_SRP_TC_1.cpp b/tests/nexus/test_1_3_SRP_TC_1.cpp
index 70fef0576..ee42be6dc 100644
--- a/tests/nexus/test_1_3_SRP_TC_1.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_1.cpp
@@ -285,6 +285,7 @@ void Test_1_3_SRP_TC_1(const char *aJsonFileName)
     Log("Step 8: Eth 1 sends mDNS query QType=PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -463,6 +464,7 @@ void Test_1_3_SRP_TC_1(const char *aJsonFileName)
     Log("Step 14: Eth 1 sends mDNS query QType=PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
diff --git a/tests/nexus/test_1_3_SRP_TC_13.cpp b/tests/nexus/test_1_3_SRP_TC_13.cpp
index fbd6ce9c0..0cc779a97 100644
--- a/tests/nexus/test_1_3_SRP_TC_13.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_13.cpp
@@ -32,8 +32,6 @@
 #include "platform/nexus_core.hpp"
 #include "platform/nexus_node.hpp"
 
-#include "common/clearable.hpp"
-
 namespace ot {
 namespace Nexus {
 
diff --git a/tests/nexus/test_1_3_SRP_TC_15.cpp b/tests/nexus/test_1_3_SRP_TC_15.cpp
index 1d7f07297..a2266e266 100644
--- a/tests/nexus/test_1_3_SRP_TC_15.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_15.cpp
@@ -242,6 +242,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
     Log("Step 8: Eth 1 sends mDNS query QType PTR for service type");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -307,6 +308,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
         snprintf(subServiceType, sizeof(subServiceType), "%s._sub.%s", kSrpSubtype1, kSrpServiceType);
 
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = subServiceType;
@@ -374,6 +376,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
         snprintf(subServiceType, sizeof(subServiceType), "%s._sub.%s", kSrpSubtype2, kSrpServiceType);
 
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = subServiceType;
@@ -412,6 +415,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
         snprintf(subServiceType, sizeof(subServiceType), "%s._sub.%s", kSrpSubtype1, kSrpServiceType);
 
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = subServiceType;
@@ -441,6 +445,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
     Log("Step 20: Eth 1 sends mDNS query QType PTR for the parent service type");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -474,6 +479,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
         snprintf(subServiceType, sizeof(subServiceType), "%s._sub.%s", kSrpSubtypeInvalid, kSrpServiceType);
 
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = subServiceType;
@@ -538,6 +544,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
         snprintf(subServiceType, sizeof(subServiceType), "%s._sub.%s", kSrpSubtype2, kSrpServiceType);
 
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = subServiceType;
@@ -570,6 +577,7 @@ void Test_1_3_SRP_TC_15(const char *aJsonFileName)
         snprintf(subServiceType, sizeof(subServiceType), "%s._sub.%s", kSrpSubtype1, kSrpServiceType);
 
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = subServiceType;
diff --git a/tests/nexus/test_1_3_SRP_TC_2.cpp b/tests/nexus/test_1_3_SRP_TC_2.cpp
index 560ea7715..6378a7fae 100644
--- a/tests/nexus/test_1_3_SRP_TC_2.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_2.cpp
@@ -251,6 +251,7 @@ void Test_1_3_SRP_TC_2(const char *aJsonFileName)
     Log("Step 8: Eth 1 performs mDNS query QType PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -372,6 +373,7 @@ void Test_1_3_SRP_TC_2(const char *aJsonFileName)
     Log("Step 12: Eth 1 repeats mDNS query QType PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -459,6 +461,7 @@ void Test_1_3_SRP_TC_2(const char *aJsonFileName)
     Log("Step 16: Eth 1 performs mDNS query QType PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
diff --git a/tests/nexus/test_1_3_SRP_TC_3.cpp b/tests/nexus/test_1_3_SRP_TC_3.cpp
index 21ac3dbff..9c897dd8f 100644
--- a/tests/nexus/test_1_3_SRP_TC_3.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_3.cpp
@@ -370,6 +370,7 @@ void Test_1_3_SRP_TC_3(const char *aJsonFileName)
     Log("Step 16: Eth 1 sends mDNS query QType PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -494,6 +495,7 @@ void Test_1_3_SRP_TC_3(const char *aJsonFileName)
     Log("Step 25: Eth 1 sends mDNS query QType PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
diff --git a/tests/nexus/test_1_3_SRP_TC_4.cpp b/tests/nexus/test_1_3_SRP_TC_4.cpp
index c6d58b40f..c4ffeb606 100644
--- a/tests/nexus/test_1_3_SRP_TC_4.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_4.cpp
@@ -369,7 +369,7 @@ void Test_1_3_SRP_TC_4(const char *aJsonFileName)
     {
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
-        browser.mServiceType  = "_thread-test._udp";
+        browser.mServiceType  = kSrpServiceType;
         browser.mInfraIfIndex = kInfraIfIndex;
         SuccessOrQuit(eth1.Get<Dns::Multicast::Core>().StartBrowser(browser));
     }
@@ -408,6 +408,10 @@ void Test_1_3_SRP_TC_4(const char *aJsonFileName)
      *   - N/A
      */
     Log("Step 19: Eth 1 sends mDNS query QType PTR.");
+    ClearAllBytes(browser);
+    browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
+    browser.mServiceType  = kSrpServiceType;
+    browser.mInfraIfIndex = kInfraIfIndex;
     SuccessOrQuit(eth1.Get<Dns::Multicast::Core>().StartBrowser(browser));
     nexus.AdvanceTime(kDnsQueryTime);
 
diff --git a/tests/nexus/test_1_3_SRP_TC_5.cpp b/tests/nexus/test_1_3_SRP_TC_5.cpp
index 48c6dc6ba..33ea2e901 100644
--- a/tests/nexus/test_1_3_SRP_TC_5.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_5.cpp
@@ -244,6 +244,7 @@ void Test_1_3_SRP_TC_5(const char *aJsonFileName)
     Log("Step 8: Eth_1 send mDNS QType=PTR query.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -306,6 +307,7 @@ void Test_1_3_SRP_TC_5(const char *aJsonFileName)
     Log("Step 10.8: Eth_1 send mDNS QType=PTR query.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
diff --git a/tests/nexus/test_1_3_SRP_TC_6.cpp b/tests/nexus/test_1_3_SRP_TC_6.cpp
index b10d77107..c072e73b6 100644
--- a/tests/nexus/test_1_3_SRP_TC_6.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_6.cpp
@@ -236,6 +236,7 @@ void Test_1_3_SRP_TC_6(const char *aJsonFileName)
     Log("Step 8: Eth 1 sends mDNS query QType=PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
@@ -331,6 +332,7 @@ void Test_1_3_SRP_TC_6(const char *aJsonFileName)
     Log("Step 8 (Repeat): Eth 1 sends mDNS query QType=PTR.");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
diff --git a/tests/nexus/test_1_3_SRP_TC_8.cpp b/tests/nexus/test_1_3_SRP_TC_8.cpp
index 364d8899b..3110abc4f 100644
--- a/tests/nexus/test_1_3_SRP_TC_8.cpp
+++ b/tests/nexus/test_1_3_SRP_TC_8.cpp
@@ -32,8 +32,6 @@
 #include "platform/nexus_core.hpp"
 #include "platform/nexus_node.hpp"
 
-#include "common/clearable.hpp"
-
 namespace ot {
 namespace Nexus {
 
@@ -453,6 +451,7 @@ void Test_1_3_SRP_TC_8(const char *aJsonFileName)
     Log("Step 24: Eth 1 sends mDNS query PTR for services");
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = [](otInstance *, const otPlatDnssdBrowseResult *) {};
         browser.mServiceType  = kSrpServiceType;
diff --git a/tests/nexus/test_1_4_CS_TC_3.cpp b/tests/nexus/test_1_4_CS_TC_3.cpp
index 63c577222..76f31cb84 100644
--- a/tests/nexus/test_1_4_CS_TC_3.cpp
+++ b/tests/nexus/test_1_4_CS_TC_3.cpp
@@ -201,6 +201,7 @@ static void DiscoverMeshcopEService(Node &aCommNode, Core &aNexus, Ip6::Address
     sBrowseOutcomes.Clear();
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mServiceType  = "_meshcop-e._udp";
         browser.mInfraIfIndex = kInfraIfIndex;
@@ -350,6 +351,7 @@ void Test1_4_CS_TC_3(void)
 
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mServiceType  = "_meshcop._udp";
         browser.mInfraIfIndex = kInfraIfIndex;
@@ -604,6 +606,7 @@ void Test1_4_CS_TC_3(void)
 
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mServiceType  = "_meshcop-e._udp";
         browser.mInfraIfIndex = kInfraIfIndex;
@@ -893,6 +896,7 @@ void Test1_4_CS_TC_3(void)
 
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mServiceType  = "_meshcop-e._udp";
         browser.mInfraIfIndex = kInfraIfIndex;
diff --git a/tests/nexus/test_1_4_TREL_TC_6.cpp b/tests/nexus/test_1_4_TREL_TC_6.cpp
index 043eb437c..498d2fa21 100644
--- a/tests/nexus/test_1_4_TREL_TC_6.cpp
+++ b/tests/nexus/test_1_4_TREL_TC_6.cpp
@@ -153,6 +153,7 @@ void Test_1_4_TREL_TC_6(void)
     SuccessOrQuit(eth1.Get<Dns::Multicast::Core>().SetEnabled(true, kInfraIfIndex));
     {
         Dns::Multicast::Core::Browser browser;
+
         ClearAllBytes(browser);
         browser.mCallback     = HandleBrowseResult;
         browser.mServiceType  = "_trel._udp";