feat: 1.0.0 changes blocking default from true to false (#537)

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: kabir

server-common/src/main/java/io/a2a/server/requesthandlers/DefaultRequestHandler.java

@@ -269,10 +269,7 @@ public EventKind onMessageSend(MessageSendParams params, ServerCallContext conte
         EventQueue queue = queueManager.createOrTap(taskId);
         ResultAggregator resultAggregator = new ResultAggregator(mss.taskManager, null, executor);
 
-        boolean blocking = true; // Default to blocking behavior
-        if (params.configuration() != null && Boolean.FALSE.equals(params.configuration().blocking())) {
-            blocking = false;
-        }
+        boolean blocking = params.configuration() != null && Boolean.TRUE.equals(params.configuration().blocking());
 
         boolean interruptedOrNonBlocking = false;
 

server-common/src/test/java/io/a2a/server/requesthandlers/DefaultRequestHandlerTest.java

@@ -516,9 +516,8 @@ void testNonBlockingMessagePersistsAllEventsInBackground() throws Exception {
             .contextId(contextId)
             .build();
 
-        // Set blocking=false for non-blocking behavior
+        // Use default non-blocking behavior
         MessageSendConfiguration config = new MessageSendConfiguration.Builder()
-                .blocking(false)
                 .build();
 
         MessageSendParams params = new MessageSendParams(message, config, null);
@@ -880,7 +879,7 @@ void testBlockingMessageStoresPushNotificationConfigForNewTask() throws Exceptio
      */
     @Test
     @Timeout(10)
-    void testMessageStoresPushNotificationConfigForExistingTask() throws Exception {
+    void testBlockingMessageStoresPushNotificationConfigForExistingTask() throws Exception {
         String taskId = "push-config-existing-task";
         String contextId = "push-config-existing-ctx";
 

spec-grpc/src/test/java/io/a2a/grpc/utils/ToProtoTest.java

@@ -3,6 +3,7 @@
 import static io.a2a.grpc.Role.ROLE_AGENT;
 import static io.a2a.grpc.Role.ROLE_USER;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 import io.a2a.grpc.SendMessageConfiguration;
@@ -269,10 +270,9 @@ public void convertTaskStatusUpdateEvent() {
     public void convertSendMessageConfiguration() {
         MessageSendConfiguration configuration = new MessageSendConfiguration.Builder()
                 .acceptedOutputModes(List.of("text"))
-                .blocking(false)
                 .build();
         SendMessageConfiguration result = ProtoUtils.ToProto.messageSendConfiguration(configuration);
-        assertEquals(false, result.getBlocking());
+        assertFalse(result.getBlocking());
         assertEquals(1, result.getAcceptedOutputModesCount());
         assertEquals("text", result.getAcceptedOutputModesBytes(0).toStringUtf8());
     }

spec/src/main/java/io/a2a/spec/MessageSendConfiguration.java

@@ -16,7 +16,7 @@
  * @param acceptedOutputModes list of output modes the client can handle (e.g., "text", "audio")
  * @param historyLength number of previous messages to include in conversation context (must be non-negative)
  * @param pushNotificationConfig configuration for asynchronous push notifications when task state changes
- * @param blocking whether the request should block until task completion (defaults to true)
+ * @param blocking whether the request should block until task completion (defaults to false)
  * @see MessageSendParams for the parameters that use this configuration
  * @see PushNotificationConfig for push notification options
  * @see <a href="https://a2a-protocol.org/latest/">A2A Protocol Specification</a>
@@ -40,7 +40,7 @@ public static class Builder {
         List<String> acceptedOutputModes;
         Integer historyLength;
         PushNotificationConfig pushNotificationConfig;
-        Boolean blocking = true;
+        Boolean blocking = false;
 
         /**
          * Sets the accepted output modes.