feat: support ConditionalToolRule in new agent loop (#1977)

letta/agents/letta_agent.py

@@ -32,6 +32,7 @@ from letta.services.helpers.agent_manager_helper import compile_system_message
 from letta.services.message_manager import MessageManager
 from letta.services.passage_manager import PassageManager
 from letta.services.tool_executor.tool_execution_manager import ToolExecutionManager
+from letta.system import package_function_response
 from letta.tracing import log_event, trace_method
 from letta.utils import united_diff
 
@@ -59,6 +60,8 @@ class LettaAgent(BaseAgent):
         self.use_assistant_message = use_assistant_message
         self.response_messages: List[Message] = []
 
+        self.last_function_response = self._load_last_function_response()
+
     @trace_method
     async def step(self, input_messages: List[MessageCreate], max_steps: int = 10) -> LettaResponse:
         agent_state = self.agent_manager.get_agent_by_id(self.agent_id, actor=self.actor)
@@ -194,7 +197,12 @@ class LettaAgent(BaseAgent):
             or (t.tool_type == ToolType.EXTERNAL_COMPOSIO)
         ]
 
-        valid_tool_names = tool_rules_solver.get_allowed_tool_names(available_tools=set([t.name for t in tools]))
+        # Mirror the sync agent loop: get allowed tools or allow all if none are allowed
+        valid_tool_names = tool_rules_solver.get_allowed_tool_names(
+            available_tools=set([t.name for t in tools]),
+            last_function_response=self.last_function_response,
+        ) or list(set(t.name for t in tools))
+
         # TODO: Copied from legacy agent loop, so please be cautious
         # Set force tool
         force_tool_call = None
@@ -255,6 +263,7 @@ class LettaAgent(BaseAgent):
             tool_args=tool_args,
             agent_state=agent_state,
         )
+        function_response = package_function_response(tool_result, success_flag)
 
         # 4. Register tool call with tool rule solver
         # Resolve whether or not to continue stepping
@@ -283,6 +292,7 @@ class LettaAgent(BaseAgent):
             pre_computed_tool_message_id=pre_computed_tool_message_id,
         )
         persisted_messages = self.message_manager.create_many_messages(tool_call_messages, actor=self.actor)
+        self.last_function_response = function_response
 
         return persisted_messages, continue_stepping
 
@@ -348,10 +358,6 @@ class LettaAgent(BaseAgent):
                 results = await self._send_message_to_agents_matching_tags(**tool_args)
                 log_event(name="finish_send_message_to_agents_matching_tags", attributes=tool_args)
                 return json.dumps(results), True
-            elif target_tool.tool_type == ToolType.EXTERNAL_COMPOSIO:
-                log_event(name=f"start_composio_{tool_name}_execution", attributes=tool_args)
-                log_event(name=f"finish_compsio_{tool_name}_execution", attributes=tool_args)
-                return tool_execution_result.func_return, True
             else:
                 tool_execution_manager = ToolExecutionManager(agent_state=agent_state, actor=self.actor)
                 # TODO: Integrate sandbox result
@@ -416,3 +422,17 @@ class LettaAgent(BaseAgent):
         tasks = [asyncio.create_task(process_agent(agent_state=agent_state, message=message)) for agent_state in matching_agents]
         results = await asyncio.gather(*tasks)
         return results
+
+    def _load_last_function_response(self):
+        """Load the last function response from message history"""
+        in_context_messages = self.agent_manager.get_in_context_messages(agent_id=self.agent_id, actor=self.actor)
+        for msg in reversed(in_context_messages):
+            if msg.role == MessageRole.tool and msg.content and len(msg.content) == 1 and isinstance(msg.content[0], TextContent):
+                text_content = msg.content[0].text
+                try:
+                    response_json = json.loads(text_content)
+                    if response_json.get("message"):
+                        return response_json["message"]
+                except (json.JSONDecodeError, KeyError):
+                    raise ValueError(f"Invalid JSON format in message: {text_content}")
+        return None