feat: Adding validation to BaseAgent and RunConfig

core/src/main/java/com/google/adk/agents/BaseAgent.java

@@ -16,7 +16,9 @@
 
 package com.google.adk.agents;
 
+import static com.google.common.base.Strings.isNullOrEmpty;
 import static com.google.common.collect.ImmutableList.toImmutableList;
+import static java.lang.String.format;
 
 import com.google.adk.agents.Callbacks.AfterAgentCallback;
 import com.google.adk.agents.Callbacks.BeforeAgentCallback;
@@ -36,12 +38,17 @@
 import java.util.List;
 import java.util.Optional;
 import java.util.function.Function;
+import java.util.regex.Pattern;
 import java.util.stream.Stream;
 import org.jspecify.annotations.Nullable;
 
 /** Base class for all agents. */
 public abstract class BaseAgent {
 
+  // Pattern for valid agent names.
+  private static final String IDENTIFIER_REGEX = "^_?[a-zA-Z0-9]*([. _-][a-zA-Z0-9]+)*$";
+  private static final Pattern IDENTIFIER_PATTERN = Pattern.compile(IDENTIFIER_REGEX);
+
   /** The agent's name. Must be a unique identifier within the agent tree. */
   private final String name;
 
@@ -79,6 +86,7 @@ public BaseAgent(
       @Nullable List<? extends BaseAgent> subAgents,
       @Nullable List<? extends BeforeAgentCallback> beforeAgentCallback,
       @Nullable List<? extends AfterAgentCallback> afterAgentCallback) {
+    validateAgentName(name);
     this.name = name;
     this.description = description;
     this.parentAgent = null;
@@ -96,6 +104,20 @@ public BaseAgent(
     }
   }
 
+  private static void validateAgentName(String name) {
+    if (isNullOrEmpty(name)) {
+      throw new IllegalArgumentException("Agent name cannot be null or empty.");
+    }
+    if (!IDENTIFIER_PATTERN.matcher(name).matches()) {
+      throw new IllegalArgumentException(
+          format("Agent name '%s' does not match regex '%s'.", name, IDENTIFIER_REGEX));
+    }
+    if (name.equals("user")) {
+      throw new IllegalArgumentException(
+          "Agent name cannot be 'user'; reserved for end-user input.");
+    }
+  }
+
   /**
    * Gets the agent's unique name.
    *

core/src/main/java/com/google/adk/agents/RunConfig.java

@@ -134,6 +134,9 @@ public abstract Builder setInputAudioTranscription(
 
     public RunConfig build() {
       RunConfig runConfig = autoBuild();
+      if (runConfig.maxLlmCalls() == Integer.MAX_VALUE) {
+        throw new IllegalArgumentException("maxLlmCalls should be less than Integer.MAX_VALUE.");
+      }
       if (runConfig.maxLlmCalls() < 0) {
         logger.warn(
             "maxLlmCalls is negative. This will result in no enforcement on total"

core/src/test/java/com/google/adk/agents/BaseAgentTest.java

@@ -17,6 +17,7 @@
 package com.google.adk.agents;
 
 import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
 
 import com.google.adk.agents.Callbacks.AfterAgentCallback;
 import com.google.adk.agents.Callbacks.BeforeAgentCallback;
@@ -336,4 +337,18 @@ public void runLive_invokesRunLiveImpl() {
     assertThat(results.get(0).content()).hasValue(runLiveImplContent);
     assertThat(runLiveCallback.wasCalled()).isTrue();
   }
+
+  @Test
+  public void constructor_invalidName_throwsIllegalArgumentException() {
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> new TestBaseAgent("invalid name?", "description", null, null, null));
+  }
+
+  @Test
+  public void constructor_userName_throwsIllegalArgumentException() {
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> new TestBaseAgent("user", "description", null, null, null));
+  }
 }

core/src/test/java/com/google/adk/agents/RunConfigTest.java

@@ -17,6 +17,7 @@
 package com.google.adk.agents;
 
 import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.assertThrows;
 
 import com.google.common.collect.ImmutableList;
 import com.google.genai.types.AudioTranscriptionConfig;
@@ -114,4 +115,11 @@ public void testInputAudioTranscriptionOnly() {
     assertThat(runConfig.streamingMode()).isEqualTo(RunConfig.StreamingMode.BIDI);
     assertThat(runConfig.responseModalities()).containsExactly(new Modality(Modality.Known.AUDIO));
   }
+
+  @Test
+  public void testMaxLlmCalls_integerMaxValue_throwsIllegalArgumentException() {
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> RunConfig.builder().setMaxLlmCalls(Integer.MAX_VALUE).build());
+  }
 }