fix: prevent kickoff hanging on LLM auth failures

- Move iteration counter increment before LLM call
- Add proper error handling for LLM failures
- Implement max iterations check and handling
- Add error messaging for failed LLM calls

This prevents the agent from hanging in an infinite loop when LLM
authentication fails by properly incrementing the iteration counter
and respecting the max_iterations limit.

Co-Authored-By: brandon@crewai.com <brandon@crewai.com>

src/crewai/agents/crew_agent_executor.py

@@ -108,14 +108,42 @@ class CrewAgentExecutor(CrewAgentExecutorMixin):
         self._create_long_term_memory(formatted_answer)
         return {"output": formatted_answer.output}
 
+    def _has_reached_max_iterations(self) -> bool:
+        """Check if the maximum number of iterations has been reached."""
+        return self.iterations >= self.max_iter
+
+    def _handle_max_iterations_exceeded(self, formatted_answer) -> AgentFinish:
+        """Handle the case when maximum iterations have been exceeded."""
+        error_msg = f"Agent has exceeded maximum iterations ({self.max_iter}). This could be due to repeated failures or infinite loops."
+        self._printer.print(content=error_msg, color="red")
+        return AgentFinish(
+            thought="Maximum iterations exceeded",
+            output=error_msg,
+            text=formatted_answer.text if formatted_answer else error_msg
+        )
+
     def _invoke_loop(self, formatted_answer=None):
         try:
             while not isinstance(formatted_answer, AgentFinish):
                 if not self.request_within_rpm_limit or self.request_within_rpm_limit():
-                    answer = self.llm.call(
-                        self.messages,
-                        callbacks=self.callbacks,
-                    )
+                    # Increment iteration counter before LLM call to prevent hanging
+                    self.iterations += 1
+                    
+                    try:
+                        answer = self.llm.call(
+                            self.messages,
+                            callbacks=self.callbacks,
+                        )
+                    except Exception as llm_error:
+                        self._printer.print(
+                            content=f"LLM call failed: {str(llm_error)}",
+                            color="red",
+                        )
+                        # Check if we've reached max iterations to avoid infinite loops
+                        if self._has_reached_max_iterations():
+                            return self._handle_max_iterations_exceeded(formatted_answer)
+                        # Re-raise authentication and other critical errors
+                        raise
 
                     if answer is None or answer == "":
                         self._printer.print(
@@ -136,7 +164,6 @@ class CrewAgentExecutor(CrewAgentExecutorMixin):
                             ):
                                 answer = answer.split("Observation:")[0].strip()
 
-                    self.iterations += 1
                     formatted_answer = self._format_answer(answer)
 
                     if isinstance(formatted_answer, AgentAction):