content: /*
   * Copyright 2024-2025 the original author or authors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     https://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package io.github.a2ap.core.model;
  
  /**
   * Marker interface for responses returned by synchronous message sending operations.
   * 
   * This interface serves as a common type for all possible response objects that can be
   * returned when sending a message to an agent in a non-streaming context. The response
   * can be either:
   * 
   * - A Message object: When the agent provides an immediate response
   * - A Task object: When the agent creates a task to handle the request asynchronously
   * 
   * This design allows for flexible response handling while maintaining type safety
   * in the A2A protocol implementation. Clients can check the actual type of the
   * response to determine the appropriate handling strategy.
   */
  public interface SendMessageResponse {
  
  }
  