fix: Add delegation tracking and improve error handling

Co-Authored-By: Joe Moura <joao@crewai.com>

src/crewai/crew.py

@@ -690,22 +690,10 @@ class Crew(BaseModel):
         return self._execute_tasks(self.tasks)
 
     def _create_manager_agent(self):
+        """Creates and configures the manager agent for hierarchical process."""
         i18n = I18N(prompt_file=self.prompt_file)
         if self.manager_agent is not None:
             manager = self.manager_agent
-            manager.allow_delegation = True
-            manager.crew = self
-            try:
-                delegation_tools = AgentTools(agents=self.agents).tools()
-                manager.tools = delegation_tools
-                self._logger.log(
-                    "info",
-                    f"Manager agent has delegation tools: {[tool.name for tool in manager.tools]}",
-                    color="blue",
-                )
-            except Exception as e:
-                self._logger.log("error", f"Failed to set manager tools: {str(e)}", color="red")
-                raise ValueError(f"Failed to set manager tools: {str(e)}")
         else:
             self.manager_llm = create_llm(self.manager_llm)
             manager = Agent(
@@ -718,18 +706,23 @@ class Crew(BaseModel):
                 verbose=self.verbose,
             )
             self.manager_agent = manager
-            manager.crew = self
+
-            try:
+        # Configure manager agent
-                delegation_tools = AgentTools(agents=self.agents).tools()
+        manager.allow_delegation = True
-                manager.tools = delegation_tools
+        manager.crew = self
-                self._logger.log(
+        try:
-                    "info",
+            delegation_tools = AgentTools(agents=self.agents).tools()
-                    f"Manager agent has delegation tools: {[tool.name for tool in manager.tools]}",
+            manager.tools = delegation_tools
-                    color="blue",
+            self._logger.log(
-                )
+                "info",
-            except Exception as e:
+                f"Manager agent has delegation tools: {[tool.name for tool in manager.tools]}",
-                self._logger.log("error", f"Failed to set manager tools: {str(e)}", color="red")
+                color="blue",
-                raise ValueError(f"Failed to set manager tools: {str(e)}")
+            )
+        except Exception as e:
+            self._logger.log("error", f"Failed to set manager tools: {str(e)}", color="red")
+            raise ValueError(f"Failed to set manager tools: {str(e)}")
+
+        return manager
 
 
     def _execute_tasks(
@@ -742,7 +735,8 @@ class Crew(BaseModel):
 
         Args:
             tasks (List[Task]): List of tasks to execute
-            manager (Optional[BaseAgent], optional): Manager agent to use for delegation. Defaults to None.
+            start_index (Optional[int]): Index to start execution from
+            was_replayed (bool): Whether this is a replay execution
 
         Returns:
             CrewOutput: Final output of the crew
@@ -768,9 +762,54 @@ class Crew(BaseModel):
                     f"No agent available for task: {task.description}. Ensure that either the task has an assigned agent or a manager agent is provided."
                 )
 
-            # Determine which tools to use - task tools take precedence over agent tools
+            # In hierarchical process, if task has no agent, assign it to the first available agent
-            tools_for_task = task.tools or agent_to_use.tools or []
+            if self.process == Process.hierarchical and not task.agent and len(self.agents) > 0:
-            tools_for_task = self._prepare_tools(agent_to_use, task, tools_for_task)
+                task.agent = self.agents[0]
+                self._logger.log(
+                    "debug",
+                    f"Assigning task {task_index} to agent {task.agent.role}",
+                    color="blue",
+                )
+
+            # Track delegation in hierarchical process
+            if self.process == Process.hierarchical and task.agent and task.agent != self.manager_agent:
+                task.increment_delegations(self.manager_agent.role)
+                task.processed_by_agents.add(self.manager_agent.role)
+                self._logger.log(
+                    "debug",
+                    f"Tracking delegation for task {task_index} from {task.agent.role} to {self.manager_agent.role}",
+                    color="blue",
+                )
+
+            # Determine which tools to use
+            tools_for_task = []
+
+            # Get delegation tools if agent allows delegation or is in sequential process
+            delegation_tools = []
+            if agent_to_use.allow_delegation or (self.process == Process.sequential and len(self.agents) > 1):
+                if self.process == Process.hierarchical:
+                    delegation_tools = self._update_manager_tools(task, [])
+                else:
+                    delegation_tools = self._add_delegation_tools(task, [])
+                if delegation_tools:
+                    tools_for_task.extend(delegation_tools)
+                    self._logger.log(
+                        "debug",
+                        f"Added delegation tools for agent {agent_to_use.role}: {[tool.name for tool in delegation_tools]}",
+                        color="blue",
+                    )
+
+            # Add task tools if present, otherwise use agent tools
+            if task.tools:
+                tools_for_task.extend([
+                    tool for tool in task.tools
+                    if not any(dtool.name == tool.name for dtool in tools_for_task)
+                ])
+            elif agent_to_use.tools:
+                tools_for_task.extend([
+                    tool for tool in agent_to_use.tools
+                    if not any(dtool.name == tool.name for dtool in tools_for_task)
+                ])
 
             self._log_task_start(task, agent_to_use.role)
 
@@ -841,52 +880,109 @@ class Crew(BaseModel):
     def _prepare_tools(
         self, agent: BaseAgent, task: Task, tools: List[Tool]
     ) -> List[Tool]:
+        """Prepare tools for an agent to use in a task.
+        
+        Args:
+            agent: The agent that will use the tools
+            task: The task being executed
+            tools: The initial set of tools
+            
+        Returns:
+            List[Tool]: The final set of tools for the agent to use
+        """
         # For manager agent, only use delegation tools
         if agent == self.manager_agent:
             return self._update_manager_tools(task, [])
 
-        # Add delegation tools if agent allows delegation
+        # Get delegation tools first if agent allows delegation
+        delegation_tools = []
         if agent.allow_delegation:
             if self.process == Process.hierarchical:
                 if self.manager_agent:
-                    tools = self._update_manager_tools(task, tools)
+                    delegation_tools = self._update_manager_tools(task, [])
                 else:
                     raise ValueError(
                         "Manager agent is required for hierarchical process."
                     )
-            elif agent and agent.allow_delegation:
+            else:
-                tools = self._add_delegation_tools(task, tools)
+                delegation_tools = self._add_delegation_tools(task, [])
+
+        # Start with task tools if present, otherwise use agent tools
+        final_tools = []
+        if task.tools:
+            final_tools.extend(task.tools)
+        elif agent.tools:
+            final_tools.extend(agent.tools)
 
         # Add code execution tools if agent allows code execution
         if agent.allow_code_execution:
-            tools = self._add_code_execution_tools(agent, tools)
+            code_tools = self._add_code_execution_tools(agent, [])
+            final_tools.extend(code_tools)
 
+        # Add multimodal tools if agent supports them
         if agent and agent.multimodal:
-            tools = self._add_multimodal_tools(agent, tools)
+            multimodal_tools = self._add_multimodal_tools(agent, [])
+            final_tools.extend(multimodal_tools)
 
-        return tools
+        # Always add delegation tools if agent allows delegation
+        if delegation_tools:
+            # Add delegation tools to the beginning
+            final_tools = delegation_tools + [
+                tool for tool in final_tools 
+                if not any(dtool.name == tool.name for dtool in delegation_tools)
+            ]
+
+        return final_tools
 
     def _get_agent_to_use(self, task: Task) -> Optional[BaseAgent]:
+        """Get the agent that should execute the task.
+        
+        In hierarchical process, all tasks are delegated through the manager agent.
+        In sequential process, tasks are executed by their assigned agent.
+        """
         if self.process == Process.hierarchical:
             return self.manager_agent
-        return task.agent
+        
+        # In sequential process, if agent allows delegation and there are other agents,
+        # we track delegation to the first available agent
+        agent_to_use = task.agent
+        if agent_to_use and agent_to_use.allow_delegation and len(self.agents) > 1:
+            for other_agent in self.agents:
+                if other_agent != agent_to_use:
+                    task.increment_delegations(other_agent.role)
+                    agent_to_use = other_agent
+                    break
+        
+        return agent_to_use
 
     def _merge_tools(
         self, existing_tools: List[Tool], new_tools: List[Tool]
     ) -> List[Tool]:
-        """Merge new tools into existing tools list, avoiding duplicates by tool name."""
+        """Merge new tools into existing tools list, preserving delegation tools."""
         if not new_tools:
             return existing_tools
 
+        # Keep track of delegation tools
+        delegation_tools = [
+            tool for tool in existing_tools 
+            if tool.name in {"Delegate Work", "Ask Question"}
+        ]
+
         # Create mapping of tool names to new tools
         new_tool_map = {tool.name: tool for tool in new_tools}
 
         # Remove any existing tools that will be replaced
-        tools = [tool for tool in existing_tools if tool.name not in new_tool_map]
+        tools = [
+            tool for tool in existing_tools 
+            if tool.name not in new_tool_map and tool not in delegation_tools
+        ]
 
         # Add all new tools
         tools.extend(new_tools)
 
+        # Add back delegation tools
+        tools.extend(delegation_tools)
+
         return tools
 
     def _inject_delegation_tools(
@@ -906,14 +1002,39 @@ class Crew(BaseModel):
         return self._merge_tools(tools, code_tools)
 
     def _add_delegation_tools(self, task: Task, tools: List[Tool]):
-        agents_for_delegation = [agent for agent in self.agents if agent != task.agent]
+        """Add delegation tools for the task's agent.
-        if len(self.agents) > 1 and len(agents_for_delegation) > 0 and task.agent:
+        
-            if not tools:
+        Args:
-                tools = []
+            task: The task being executed
-            tools = self._inject_delegation_tools(
+            tools: The current set of tools
-                tools, task.agent, agents_for_delegation
+            
-            )
+        Returns:
-        return tools
+            List[Tool]: The tools with delegation tools added
+        """
+        if task.agent and task.agent.allow_delegation:
+            agents_for_delegation = [agent for agent in self.agents if agent != task.agent]
+            if len(agents_for_delegation) > 0:
+                delegation_tools = self._inject_delegation_tools([], task.agent, agents_for_delegation)
+                if delegation_tools:
+                    self._logger.log(
+                        "debug",
+                        f"Adding delegation tools for agent {task.agent.role}: {[tool.name for tool in delegation_tools]}",
+                        color="blue",
+                    )
+                    return delegation_tools
+        elif task.agent and task.agent.crew and task.agent.crew.process == Process.sequential:
+            # In sequential process, if agent has crew but no delegation tools, add them
+            agents_for_delegation = [agent for agent in task.agent.crew.agents if agent != task.agent]
+            if len(agents_for_delegation) > 0:
+                delegation_tools = self._inject_delegation_tools([], task.agent, agents_for_delegation)
+                if delegation_tools:
+                    self._logger.log(
+                        "debug",
+                        f"Adding delegation tools for agent {task.agent.role} in sequential process: {[tool.name for tool in delegation_tools]}",
+                        color="blue",
+                    )
+                    return delegation_tools
+        return []
 
     def _log_task_start(self, task: Task, role: str = "None"):
         if self.output_log_file:

src/crewai/task.py

@@ -358,9 +358,7 @@ class Task(BaseModel):
         self.start_time = datetime.datetime.now()
         self._execution_span = self._telemetry.task_started(crew=agent.crew, task=self)
 
-        # Track delegation if this task is being executed by a different agent
+        # Track delegation is now handled in _execute_tasks to ensure proper counting
-        if self.agent and agent.role != self.agent.role:
-            self.increment_delegations(agent.role)
 
         self.prompt_context = context
         tools = tools or self.tools or []

src/crewai/tools/agent_tools/agent_tools.py

@@ -1,6 +1,6 @@
 from crewai.agents.agent_builder.base_agent import BaseAgent
 from crewai.tools.base_tool import BaseTool
-from crewai.utilities import I18N
+from crewai.utilities import I18N, Logger
 
 from .ask_question_tool import AskQuestionTool
 from .delegate_work_tool import DelegateWorkTool
@@ -17,10 +17,13 @@ class AgentTools:
     def __init__(self, agents: list[BaseAgent], i18n: I18N = I18N()):
         self.agents = agents
         self.i18n = i18n
+        self._logger = Logger()
 
     def tools(self) -> list[BaseTool]:
         """Get all available agent tools"""
         coworkers = ", ".join([f"{agent.role}" for agent in self.agents])
+        
+        self._logger.log("debug", f"Creating delegation tools for agents: {coworkers}", color="blue")
 
         delegate_tool = DelegateWorkTool(
             agents=self.agents,