fix(spring): make A2A server auto-configuration opt-in

docs/en/API_REFERENCE.md

@@ -609,7 +609,7 @@ not add private negotiation-state keys to the wire message.
 ## spring-boot-starter Module
 
 The `spring-boot-starter` module provides Spring Boot auto-configuration for the A2A **server** side (not the
-client/workflow side). When on the classpath of a Spring Boot web application, it auto-registers all A2A SDK server
+client/workflow side). In a Spring Boot web application, set `a2at.server.enabled=true` to register the A2A SDK server
 components as Spring beans.
 
 ### A2AProperties
@@ -618,6 +618,7 @@ Configuration properties prefixed with `a2at.server`:
 
 | Property                                     | Default                    | Description                                                            |
 |----------------------------------------------|----------------------------|------------------------------------------------------------------------|
+| `a2at.server.enabled`                        | `false`                    | Enable A2A server auto-configuration                                   |
 | `a2at.server.agent-card`                     | `classpath:agentcard.json` | Path to the AgentCard JSON file (classpath: or file: prefix supported) |
 | `a2at.server.path-prefix`                    | `/a2a/json`                | URL path prefix for A2A endpoints                                      |
 | `a2at.server.slash-action-aliases-enabled`   | `false`                    | Expose slash-style action aliases for gateways that reject colons      |
@@ -632,6 +633,7 @@ Configuration properties prefixed with `a2at.server`:
 ```yaml
 a2at:
   server:
+    enabled: true
     agent-card: classpath:agentcard/my_agent.json
     path-prefix: /a2a/json
     slash-action-aliases-enabled: false
@@ -658,7 +660,7 @@ Auto-configures the following beans (all `@ConditionalOnMissingBean`, so you can
 | `requestHandler`    | `RequestHandler`              | Default request handler                                   |
 | `restHandler`       | `RestHandler`                 | REST protocol handler                                     |
 | `a2aController`     | `A2AController`               | Spring MVC controller for message and task endpoints     |
-| `a2aSlashActionAliasController` | internal controller | Optional slash-style aliases for action endpoints         |
+| `a2aSlashActionAliasController` | `A2ASlashActionAliasController` | Optional public controller for slash-style action aliases |
 
 ### A2AController
 

docs/en/INTEGRATION_GUIDE.md

@@ -565,6 +565,7 @@ If the gateway cannot rewrite the backend path, enable the starter's aliases:
 ```yaml
 a2at:
   server:
+    enabled: true
     path-prefix: /a2a/json
     slash-action-aliases-enabled: true
 ```

docs/zh/API_REFERENCE.md

@@ -575,15 +575,16 @@ getReceivedMessages() 是保留层级的响应来源，getOutputs() 为便利投
 
 ## spring-boot-starter 模块
 
-`spring-boot-starter` 模块为 A2A **服务端**（非客户端/工作流侧）提供 Spring Boot 自动配置。当位于 Spring Boot Web 应用的
-classpath 时，自动将所有 A2A SDK 服务端组件注册为 Spring Bean。
+`spring-boot-starter` 模块为 A2A **服务端**（非客户端/工作流侧）提供 Spring Boot 自动配置。在 Spring Boot Web 应用中配置
+`a2at.server.enabled=true` 后，才会将 A2A SDK 服务端组件注册为 Spring Bean。
 
 ### A2AProperties
 
 以 `a2at.server` 为前缀的配置属性：
 
 | 属性                                         | 默认值                     | 说明                                                     |
 |----------------------------------------------|----------------------------|----------------------------------------------------------|
+| `a2at.server.enabled`                        | `false`                    | 启用 A2A 服务端自动配置                                  |
 | `a2at.server.agent-card`                     | `classpath:agentcard.json` | AgentCard JSON 文件路径（支持 classpath: 或 file: 前缀） |
 | `a2at.server.path-prefix`                    | `/a2a/json`                | A2A 端点的 URL 路径前缀                                  |
 | `a2at.server.slash-action-aliases-enabled`   | `false`                    | 为拒绝冒号路径的网关暴露斜杠动作别名                    |
@@ -598,6 +599,7 @@ classpath 时，自动将所有 A2A SDK 服务端组件注册为 Spring Bean。
 ```yaml
 a2at:
   server:
+    enabled: true
     agent-card: classpath:agentcard/my_agent.json
     path-prefix: /a2a/json
     slash-action-aliases-enabled: false
@@ -624,7 +626,7 @@ a2at:
 | `requestHandler`    | `RequestHandler`              | 默认请求处理器                                         |
 | `restHandler`       | `RestHandler`                 | REST 协议处理器                                        |
 | `a2aController`     | `A2AController`               | 消息和任务端点的 Spring MVC 控制器                    |
-| `a2aSlashActionAliasController` | 内部控制器         | 可选的斜杠形式动作端点别名                            |
+| `a2aSlashActionAliasController` | `A2ASlashActionAliasController` | 可选的斜杠动作别名公共控制器                    |
 
 ### A2AController
 

docs/zh/INTEGRATION_GUIDE.md

@@ -530,6 +530,7 @@ A2A HTTP+JSON 定义了 `message:send`、`message:stream`、`tasks/{id}:cancel`
 ```yaml
 a2at:
   server:
+    enabled: true
     path-prefix: /a2a/json
     slash-action-aliases-enabled: true
 ```

samples/src/main/resources/application.yml

@@ -14,6 +14,7 @@ spring:
 
 a2at:
   server:
+    enabled: true
     agent-card: classpath:agentcard/transport_workbench_agent.json
     path-prefix: /a2a/json
 

spring-boot-starter/src/main/java/dev/openan/workflow/engine/spring/A2AAutoConfiguration.java

@@ -71,13 +71,13 @@
  * </ul>
  *
  * <p>The partner only needs to provide an {@link AgentExecutor} implementation as a
- * {@code @Component} or {@code @Bean}. Set {@code a2at.server.enabled=false} to disable the whole
+ * {@code @Component} or {@code @Bean}. Set {@code a2at.server.enabled=true} to enable the
  * server-side autoconfiguration.
  */
 @AutoConfiguration
 @ConditionalOnWebApplication
 @ConditionalOnClass(AgentExecutor.class)
-@ConditionalOnProperty(name = "a2at.server.enabled", havingValue = "true", matchIfMissing = true)
+@ConditionalOnProperty(name = "a2at.server.enabled", havingValue = "true")
 @EnableConfigurationProperties(A2AProperties.class)
 public class A2AAutoConfiguration {
 

spring-boot-starter/src/main/java/dev/openan/workflow/engine/spring/A2AProperties.java

@@ -30,8 +30,8 @@
 @ConfigurationProperties(prefix = "a2at.server")
 public class A2AProperties {
 
-  /** Whether A2A server autoconfiguration is enabled. Set false to disable all A2A beans. */
-  private boolean enabled = true;
+  /** Whether A2A server autoconfiguration is enabled. Set true to create the A2A server beans. */
+  private boolean enabled = false;
 
   /** Path to the AgentCard JSON file (classpath: or file: prefix supported). */
   private String agentCard = "classpath:agentcard.json";

spring-boot-starter/src/main/java/dev/openan/workflow/engine/spring/A2ASlashActionAliasController.java

@@ -35,13 +35,14 @@
  */
 @RestController
 @ConditionalOnProperty(
-    name = "a2at.server.slash-action-aliases-enabled",
+    prefix = "a2at.server",
+    name = {"enabled", "slash-action-aliases-enabled"},
     havingValue = "true")
-final class A2ASlashActionAliasController {
+public class A2ASlashActionAliasController {
 
   private final A2AController delegate;
 
-  A2ASlashActionAliasController(A2AController delegate) {
+  public A2ASlashActionAliasController(A2AController delegate) {
     this.delegate = delegate;
   }
 

spring-boot-starter/src/test/java/dev/openan/workflow/engine/spring/A2AAutoConfigurationTest.java

@@ -36,6 +36,7 @@
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 import static org.hamcrest.Matchers.containsString;
 
+import java.lang.reflect.Modifier;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Flow;
 import java.util.concurrent.ThreadPoolExecutor;
@@ -410,7 +411,8 @@ void slashActionAliasesAreOptIn() {
             .withBean(AgentExecutor.class, () -> mock(AgentExecutor.class))
             .withBean(RequestHandler.class, () -> mock(RequestHandler.class))
             .withBean(RestHandler.class, () -> mock(RestHandler.class))
-            .withBean(A2AController.class, () -> canonical);
+            .withBean(A2AController.class, () -> canonical)
+            .withPropertyValues("a2at.server.enabled=true");
 
     runner.run(
         context -> assertFalse(context.containsBean("a2aSlashActionAliasController")));
@@ -427,6 +429,17 @@ void slashActionAliasPropertyDefaultsToDisabled() {
     assertTrue(properties.isSlashActionAliasesEnabled());
   }
 
+  @Test
+  void slashActionAliasControllerIsPubliclyAccessible() throws Exception {
+    assertTrue(Modifier.isPublic(A2ASlashActionAliasController.class.getModifiers()));
+    assertFalse(Modifier.isFinal(A2ASlashActionAliasController.class.getModifiers()));
+    assertTrue(
+        Modifier.isPublic(
+            A2ASlashActionAliasController.class
+                .getConstructor(A2AController.class)
+                .getModifiers()));
+  }
+
   @Test
   void blockingTimeoutsComeFromProperties() {
     A2AProperties properties = new A2AProperties();
@@ -487,6 +500,24 @@ void whenEnabledFalseThenNoA2ABeansCreated() {
             });
   }
 
+  @Test
+  void whenEnabledIsMissingThenNoA2ABeansCreated() {
+    new WebApplicationContextRunner()
+        .withConfiguration(AutoConfigurations.of(A2AAutoConfiguration.class))
+        .run(
+            context -> {
+              assertFalse(context.containsBean("a2aController"));
+              assertFalse(context.containsBean("agentExecutorPool"));
+              assertFalse(context.containsBean("eventBus"));
+            });
+  }
+
+  @Test
+  void serverEnabledPropertyDefaultsToFalse() {
+    A2AProperties properties = new A2AProperties();
+    assertFalse(properties.isEnabled());
+  }
+
   @Test
   void whenEnabledTrueThenA2ABeansCreated() {
     new WebApplicationContextRunner()