feat: support function factory (#4)

backend/src/agents/lead_agent/__init__.py

@@ -1,3 +1,3 @@
-from .agent import lead_agent
+from .agent import make_lead_agent
 
-__all__ = ["lead_agent"]
+__all__ = ["make_lead_agent"]

backend/src/agents/lead_agent/agent.py

@@ -1,4 +1,5 @@
 from langchain.agents import create_agent
+from langchain_core.runnables import RunnableConfig
 
 from src.agents.lead_agent.prompt import apply_prompt_template
 from src.agents.middlewares.thread_data_middleware import ThreadDataMiddleware
@@ -11,10 +12,15 @@ from src.tools import get_available_tools
 # ThreadDataMiddleware must be before SandboxMiddleware to ensure thread_id is available
 middlewares = [ThreadDataMiddleware(), SandboxMiddleware(), TitleMiddleware()]
 
-lead_agent = create_agent(
-    model=create_chat_model(thinking_enabled=True),
-    tools=get_available_tools(),
-    middleware=middlewares,
-    system_prompt=apply_prompt_template(),
-    state_schema=ThreadState,
-)
+
+def make_lead_agent(config: RunnableConfig):
+    thinking_enabled = config.get("configurable", {}).get("thinking_enabled", True)
+    model_name = config.get("configurable", {}).get("model_name")
+    print(f"thinking_enabled: {thinking_enabled}, model_name: {model_name}")
+    return create_agent(
+        model=create_chat_model(name=model_name, thinking_enabled=thinking_enabled),
+        tools=get_available_tools(),
+        middleware=middlewares,
+        system_prompt=apply_prompt_template(),
+        state_schema=ThreadState,
+    )

backend/src/agents/lead_agent/prompt.py

@@ -1,4 +1,3 @@
-import os
 from datetime import datetime
 
 SYSTEM_PROMPT = f"""