Use A2A DeepAgents model resolver

agent.py

@@ -16,10 +16,9 @@ import ssl
 from typing import Any
 
 import httpx
-from deepagents import create_deep_agent
+from a2a_pack.deepagents import create_a2a_deep_agent
 from langchain_core.messages import BaseMessage
 from langchain_core.tools import StructuredTool
-from langchain_openai import ChatOpenAI
 from pydantic import BaseModel, Field
 
 from a2a_pack import (
@@ -136,18 +135,9 @@ class MailuOpenapiAgent(A2AAgent):
                 ),
                 "messages": [],
             }
-        model_kwargs: dict[str, Any] = {
-            "model": creds.model,
-            "base_url": creds.base_url,
-            "api_key": creds.api_key,
-        }
-        if creds.temperature_mode != "omit" and creds.temperature is not None:
-            model_kwargs["temperature"] = creds.temperature
-        if creds.extra_body:
-            model_kwargs["extra_body"] = dict(creds.extra_body)
-        model = ChatOpenAI(**model_kwargs)
-        graph = create_deep_agent(
-            model=model,
+        graph = create_a2a_deep_agent(
+            ctx,
+            creds=creds,
             tools=self._operation_tools(ctx),
             system_prompt=self._system_prompt(),
         )