fix(autonomous-loop): omit the tools kwarg instead of passing None

Pyre flagged the call: Agent.__init__ annotates tools as List[Callable], not
Optional, so tools=parent_tools or None is an incompatible parameter type.

tools=[] is not an equivalent substitute — exists([]) is true, so an empty list
would send every sub-agent response through tool execution. Omitting the
keyword leaves the parameter at its own None default, which is what a
tool-less sub-agent had before this branch.

Author: ayaangazali

swarms/structs/autonomous_loop_utils.py

@@ -1244,19 +1244,27 @@ def create_sub_agent_tool(
             # strictly less capable than the parent asking the question itself.
             parent_tools = list(getattr(agent, "tools", None) or [])
 
+            # Omitted rather than passed as [], which is not the same thing:
+            # exists([]) is true, so an empty list sends every response
+            # through tool execution. Agent.tools is annotated List[Callable],
+            # so None is not passable either.
+            tool_kwargs = (
+                {"tools": parent_tools} if parent_tools else {}
+            )
+
             # Create sub-agent with the same LLM and tools as parent
             sub_agent = Agent(
                 id=agent_id,
                 agent_name=agent_name,
                 agent_description=agent_description,
                 system_prompt=system_prompt,  # Use custom system prompt if provided
                 model_name=agent.model_name,
-                tools=parent_tools or None,
                 # Tools need a call-then-read turn. Finite whatever the parent
                 # is, so a max_loops="auto" parent cannot recurse into sub-agents.
                 max_loops=5 if parent_tools else 1,
                 print_on=getattr(agent, "print_on", False),
                 verbose=agent.verbose,
+                **tool_kwargs,
             )
 
             # Cache the sub-agent