diff --git a/core/build.gradle b/core/build.gradle
index 8cbced662..32668a2cc 100644
--- a/core/build.gradle
+++ b/core/build.gradle
@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+import java.lang.reflect.Constructor
+
 plugins {
   id 'java-library'
 }
@@ -660,6 +662,33 @@ task outcastTest(type: FilteringTest) {
   maxParallelForks 5
 }
 
+// Whitebox test verifying that RegistryTool can be instantiated. Note the
+// use of runtimeClasspath. This test emulates the logic in RegistryCli#run.
+// A to-do is added there to refactor.
+// TODO(weiminyu): Need a similar test for Registry server.
+task registryToolIntegrationTest {
+  dependsOn compileJava
+  doLast {
+    def classLoader =
+        new URLClassLoader(sourceSets.main.runtimeClasspath.collect {
+            it.toURI().toURL()
+        } as URL[])
+    def commandClasses =
+        (classLoader.loadClass('google.registry.tools.RegistryTool')
+            .getDeclaredField('COMMAND_MAP').get(null) as Map).values()
+
+    commandClasses.each {
+      try {
+        Constructor<?> c = ((Class<?>) it).getDeclaredConstructor()
+        c.setAccessible(true)
+        c.newInstance()
+      } catch (Throwable e) {
+        throw new RuntimeException("Failed to instantiate ${it}:\n ${e}")
+      }
+    }
+  }
+}
+
 // Dedicated test suite for schema-dependent tests.
 task sqlIntegrationTest(type: FilteringTest) {
   systemProperties project.getProperties().subMap('sql_schema_resource_root')
@@ -779,7 +808,7 @@ test {
   // Don't run any tests from this task, all testing gets done in the
   // FilteringTest tasks.
   exclude "**"
-}.dependsOn(fragileTest, outcastTest, standardTest)
+}.dependsOn(fragileTest, outcastTest, standardTest, registryToolIntegrationTest)
 
 createUberJar('nomulus', 'nomulus', 'google.registry.tools.RegistryTool')
 project.nomulus.dependsOn project(':third_party').jar
diff --git a/core/gradle/dependency-locks/compileClasspath.lockfile b/core/gradle/dependency-locks/compileClasspath.lockfile
index 619076b60..b845be83b 100644
--- a/core/gradle/dependency-locks/compileClasspath.lockfile
+++ b/core/gradle/dependency-locks/compileClasspath.lockfile
@@ -205,7 +205,6 @@ org.jetbrains:annotations:17.0.0
 org.joda:joda-money:1.0.1
 org.json:json:20160810
 org.jvnet.staxex:stax-ex:1.8
-org.mockito:mockito-core:1.9.5
 org.mortbay.jetty:jetty-util:6.1.26
 org.mortbay.jetty:jetty:6.1.26
 org.objenesis:objenesis:1.2
diff --git a/core/src/main/java/google/registry/tools/RegistryCli.java b/core/src/main/java/google/registry/tools/RegistryCli.java
index 0b21014c7..4fb7ede2f 100644
--- a/core/src/main/java/google/registry/tools/RegistryCli.java
+++ b/core/src/main/java/google/registry/tools/RegistryCli.java
@@ -104,6 +104,8 @@ final class RegistryCli implements AutoCloseable, CommandRunner {
     // Create all command instances. It would be preferrable to do this in the constructor, but
     // JCommander mutates the command instances and doesn't reset them so we have to do it for every
     // run.
+    // TODO(weiminyu): extract this into a standalone static method to simplify
+    //   :core:registryToolIntegrationTest
     try {
       for (Map.Entry<String, ? extends Class<? extends Command>> entry : commands.entrySet()) {
         Command command = entry.getValue().getDeclaredConstructor().newInstance();
diff --git a/java_common.gradle b/java_common.gradle
index 6acd4ff6a..1f19579e9 100644
--- a/java_common.gradle
+++ b/java_common.gradle
@@ -54,7 +54,9 @@ tasks.test.finalizedBy jacocoTestReport
 configurations {
   deploy_jar.extendsFrom runtimeClasspath
 
-  runtimeClasspath {
+  all.findAll {
+    it.name in ['runtimeClasspath', 'compileClasspath']
+  }.each {
     // JUnit is from org.apache.beam:beam-runners-google-cloud-dataflow-java,
     // testcontainer (which we use in the nomulus tool), and json-simple.
     // We should really be excluding this, however GenerateSqlCommand in
@@ -62,7 +64,7 @@ configurations {
     //exclude group: 'junit'
     // Mockito is from org.apache.beam:beam-runners-google-cloud-dataflow-java
     // See https://issues.apache.org/jira/browse/BEAM-8862
-    exclude group: 'org.mockito', module: 'mockito-core'
+    it.exclude group: 'org.mockito', module: 'mockito-core'
   }
 }