Adding support to force a tool return to be the final answer. (#867)

* Adding support to force a tool return to be the final answer.
This will at the end of the execution return the tool output.
It will return the output of the latest tool with the flag

* Update src/crewai/agent.py

Co-authored-by: Gui Vieira <guilherme_vieira@me.com>

* Update tests/agent_test.py

Co-authored-by: Gui Vieira <guilherme_vieira@me.com>

---------

Co-authored-by: Gui Vieira <guilherme_vieira@me.com>

src/crewai/agent.py

@@ -90,6 +90,9 @@ class Agent(BaseAgent):
     response_template: Optional[str] = Field(
         default=None, description="Response format for the agent."
     )
+    tools_results: Optional[List[Any]] = Field(
+        default=[], description="Results of the tools used by the agent."
+    )
     allow_code_execution: Optional[bool] = Field(
         default=False, description="Enable code execution for the agent."
     )
@@ -116,7 +119,8 @@ class Agent(BaseAgent):
                 self.llm.callbacks.append(token_handler)
 
             if agentops and not any(
-                isinstance(handler, agentops.LangchainCallbackHandler) for handler in self.llm.callbacks
+                isinstance(handler, agentops.LangchainCallbackHandler)
+                for handler in self.llm.callbacks
             ):
                 agentops.stop_instrumenting()
                 self.llm.callbacks.append(agentops.LangchainCallbackHandler())
@@ -188,6 +192,14 @@ class Agent(BaseAgent):
         )["output"]
         if self.max_rpm:
             self._rpm_controller.stop_rpm_counter()
+
+        # If there was any tool in self.tools_results that had result_as_answer
+        # set to True, return the results of the last tool that had
+        # result_as_answer set to True
+        for tool_result in self.tools_results:
+            if tool_result.get("result_as_answer", False):
+                result = tool_result["result"]
+
         return result
 
     def format_log_to_str(