feat: Implement PaymentReceipt artifact and refine payment processing

python/examples/ap2-demo/client_agent/agent.py

@@ -13,14 +13,40 @@
 # limitations under the License.
 import httpx
 
-# Local imports
-from client_agent._task_store import TaskStore
+from google.adk.agents.remote_a2a_agent import RemoteA2aAgent
 from client_agent.client_agent import ClientAgent
 
-root_agent = ClientAgent(
-    remote_agent_addresses=[
-        "http://localhost:10000/agents/merchant_agent",
-    ],
-    http_client=httpx.AsyncClient(timeout=30),
-    task_callback=TaskStore().update_task,
-).create_agent()
+# The addresses of the remote agents this agent will talk to.
+REMOTE_AGENT_ADDRESSES = [
+    "http://localhost:10000/agents/merchant_agent",
+]
+
+
+def create_root_agent():
+    """Creates and returns the root agent."""
+    # Create an httpx client to be shared across all remote agents.
+    async_client = httpx.AsyncClient(timeout=30)
+
+    # Create RemoteA2aAgent instances for each remote agent.
+    remote_agents = []
+    for address in REMOTE_AGENT_ADDRESSES:
+        # The server exposes the agent card at a path relative to the agent's RPC endpoint.
+        agent_card_url = f"{address}/.well-known/agent-card.json"
+        agent_name = address.split("/")[-1]
+        remote_agents.append(
+            RemoteA2aAgent(
+                name=agent_name,
+                agent_card=agent_card_url,
+                httpx_client=async_client,
+            )
+        )
+
+    # Create the main orchestrator agent, passing the remote agents as tools.
+    client_agent_impl = ClientAgent(
+        remote_agents=remote_agents,
+        http_client=async_client,
+    )
+    return client_agent_impl.create_agent()
+
+
+root_agent = create_root_agent()