"""Unit tests for AgentExecutor.

Tests the Flow-based agent executor implementation including state management,
flow methods, routing logic, and error handling.
"""

from unittest.mock import Mock, patch

import pytest

from crewai.experimental.agent_executor import (
    AgentReActState,
    AgentExecutor,
)
from crewai.agents.parser import AgentAction, AgentFinish

class TestAgentReActState:
    """Test AgentReActState Pydantic model."""

    def test_state_initialization(self):
        """Test AgentReActState initialization with defaults."""
        state = AgentReActState()
        assert state.iterations == 0
        assert state.messages == []
        assert state.current_answer is None
        assert state.is_finished is False
        assert state.ask_for_human_input is False
        # Planning state fields
        assert state.plan is None
        assert state.plan_ready is False

    def test_state_with_plan(self):
        """Test AgentReActState initialization with planning fields."""
        state = AgentReActState(
            plan="Step 1: Do X\nStep 2: Do Y",
            plan_ready=True,
        )
        assert state.plan == "Step 1: Do X\nStep 2: Do Y"
        assert state.plan_ready is True

    def test_state_with_values(self):
        """Test AgentReActState initialization with values."""
        messages = [{"role": "user", "content": "test"}]
        state = AgentReActState(
            messages=messages,
            iterations=5,
            current_answer=AgentFinish(thought="thinking", output="done", text="final"),
            is_finished=True,
            ask_for_human_input=True,
        )
        assert state.messages == messages
        assert state.iterations == 5
        assert isinstance(state.current_answer, AgentFinish)
        assert state.is_finished is True
        assert state.ask_for_human_input is True


class TestAgentExecutor:
    """Test AgentExecutor class."""

    @pytest.fixture
    def mock_dependencies(self):
        """Create mock dependencies for executor."""
        llm = Mock()
        llm.supports_stop_words.return_value = True

        task = Mock()
        task.description = "Test task"
        task.human_input = False
        task.response_model = None

        crew = Mock()
        crew.verbose = False
        crew._train = False

        agent = Mock()
        agent.id = "test-agent-id"
        agent.role = "Test Agent"
        agent.verbose = False
        agent.key = "test-key"

        prompt = {"prompt": "Test prompt with {input}, {tool_names}, {tools}"}

        tools = []
        tools_handler = Mock()

        return {
            "llm": llm,
            "task": task,
            "crew": crew,
            "agent": agent,
            "prompt": prompt,
            "max_iter": 10,
            "tools": tools,
            "tools_names": "",
            "stop_words": ["Observation"],
            "tools_description": "",
            "tools_handler": tools_handler,
        }

    def test_executor_initialization(self, mock_dependencies):
        """Test AgentExecutor initialization."""
        executor = AgentExecutor(**mock_dependencies)

        assert executor.llm == mock_dependencies["llm"]
        assert executor.task == mock_dependencies["task"]
        assert executor.agent == mock_dependencies["agent"]
        assert executor.crew == mock_dependencies["crew"]
        assert executor.max_iter == 10
        assert executor.use_stop_words is True

    def test_initialize_reasoning(self, mock_dependencies):
        """Test flow entry point."""
        with patch.object(
            AgentExecutor, "_show_start_logs"
        ) as mock_show_start:
            executor = AgentExecutor(**mock_dependencies)
            result = executor.initialize_reasoning()

            assert result == "initialized"
            mock_show_start.assert_called_once()

    def test_check_max_iterations_not_reached(self, mock_dependencies):
        """Test routing when iterations < max."""
        executor = AgentExecutor(**mock_dependencies)
        executor.state.iterations = 5

        result = executor.check_max_iterations()
        assert result == "continue_reasoning"

    def test_check_max_iterations_reached(self, mock_dependencies):
        """Test routing when iterations >= max."""
        executor = AgentExecutor(**mock_dependencies)
        executor.state.iterations = 10

        result = executor.check_max_iterations()
        assert result == "force_final_answer"

    def test_route_by_answer_type_action(self, mock_dependencies):
        """Test routing for AgentAction."""
        executor = AgentExecutor(**mock_dependencies)
        executor.state.current_answer = AgentAction(
            thought="thinking", tool="search", tool_input="query", text="action text"
        )

        result = executor.route_by_answer_type()
        assert result == "execute_tool"

    def test_route_by_answer_type_finish(self, mock_dependencies):
        """Test routing for AgentFinish."""
        executor = AgentExecutor(**mock_dependencies)
        executor.state.current_answer = AgentFinish(
            thought="final thoughts", output="Final answer", text="complete"
        )

        result = executor.route_by_answer_type()
        assert result == "agent_finished"

    def test_continue_iteration(self, mock_dependencies):
        """Test iteration continuation."""
        executor = AgentExecutor(**mock_dependencies)

        result = executor.continue_iteration()

        assert result == "check_iteration"

    def test_finalize_success(self, mock_dependencies):
        """Test finalize with valid AgentFinish."""
        with patch.object(AgentExecutor, "_show_logs") as mock_show_logs:
            executor = AgentExecutor(**mock_dependencies)
            executor.state.current_answer = AgentFinish(
                thought="final thinking", output="Done", text="complete"
            )

            result = executor.finalize()

            assert result == "completed"
            assert executor.state.is_finished is True
            mock_show_logs.assert_called_once()

    def test_finalize_failure(self, mock_dependencies):
        """Test finalize skips when given AgentAction instead of AgentFinish."""
        executor = AgentExecutor(**mock_dependencies)
        executor.state.current_answer = AgentAction(
            thought="thinking", tool="search", tool_input="query", text="action text"
        )

        result = executor.finalize()

        # Should return "skipped" and not set is_finished
        assert result == "skipped"
        assert executor.state.is_finished is False

    def test_format_prompt(self, mock_dependencies):
        """Test prompt formatting."""
        executor = AgentExecutor(**mock_dependencies)
        inputs = {"input": "test input", "tool_names": "tool1, tool2", "tools": "desc"}

        result = executor._format_prompt("Prompt {input} {tool_names} {tools}", inputs)

        assert "test input" in result
        assert "tool1, tool2" in result
        assert "desc" in result

    def test_is_training_mode_false(self, mock_dependencies):
        """Test training mode detection when not in training."""
        executor = AgentExecutor(**mock_dependencies)
        assert executor._is_training_mode() is False

    def test_is_training_mode_true(self, mock_dependencies):
        """Test training mode detection when in training."""
        mock_dependencies["crew"]._train = True
        executor = AgentExecutor(**mock_dependencies)
        assert executor._is_training_mode() is True

    def test_append_message_to_state(self, mock_dependencies):
        """Test message appending to state."""
        executor = AgentExecutor(**mock_dependencies)
        initial_count = len(executor.state.messages)

        executor._append_message_to_state("test message")

        assert len(executor.state.messages) == initial_count + 1
        assert executor.state.messages[-1]["content"] == "test message"

    def test_invoke_step_callback(self, mock_dependencies):
        """Test step callback invocation."""
        callback = Mock()
        mock_dependencies["step_callback"] = callback

        executor = AgentExecutor(**mock_dependencies)
        answer = AgentFinish(thought="thinking", output="test", text="final")

        executor._invoke_step_callback(answer)

        callback.assert_called_once_with(answer)

    def test_invoke_step_callback_none(self, mock_dependencies):
        """Test step callback when none provided."""
        mock_dependencies["step_callback"] = None
        executor = AgentExecutor(**mock_dependencies)

        # Should not raise error
        executor._invoke_step_callback(
            AgentFinish(thought="thinking", output="test", text="final")
        )

    @patch("crewai.experimental.agent_executor.handle_output_parser_exception")
    def test_recover_from_parser_error(
        self, mock_handle_exception, mock_dependencies
    ):
        """Test recovery from OutputParserError."""
        from crewai.agents.parser import OutputParserError

        mock_handle_exception.return_value = None

        executor = AgentExecutor(**mock_dependencies)
        executor._last_parser_error = OutputParserError("test error")
        initial_iterations = executor.state.iterations

        result = executor.recover_from_parser_error()

        assert result == "initialized"
        assert executor.state.iterations == initial_iterations + 1
        mock_handle_exception.assert_called_once()

    @patch("crewai.experimental.agent_executor.handle_context_length")
    def test_recover_from_context_length(
        self, mock_handle_context, mock_dependencies
    ):
        """Test recovery from context length error."""
        executor = AgentExecutor(**mock_dependencies)
        executor._last_context_error = Exception("context too long")
        initial_iterations = executor.state.iterations

        result = executor.recover_from_context_length()

        assert result == "initialized"
        assert executor.state.iterations == initial_iterations + 1
        mock_handle_context.assert_called_once()

    def test_use_stop_words_property(self, mock_dependencies):
        """Test use_stop_words property."""
        mock_dependencies["llm"].supports_stop_words.return_value = True
        executor = AgentExecutor(**mock_dependencies)
        assert executor.use_stop_words is True

        mock_dependencies["llm"].supports_stop_words.return_value = False
        executor = AgentExecutor(**mock_dependencies)
        assert executor.use_stop_words is False

    def test_compatibility_properties(self, mock_dependencies):
        """Test compatibility properties for mixin."""
        executor = AgentExecutor(**mock_dependencies)
        executor.state.messages = [{"role": "user", "content": "test"}]
        executor.state.iterations = 5

        # Test that compatibility properties return state values
        assert executor.messages == executor.state.messages
        assert executor.iterations == executor.state.iterations


class TestFlowErrorHandling:
    """Test error handling in flow methods."""

    @pytest.fixture
    def mock_dependencies(self):
        """Create mock dependencies."""
        llm = Mock()
        llm.supports_stop_words.return_value = True

        task = Mock()
        task.description = "Test task"

        crew = Mock()
        agent = Mock()
        agent.role = "Test Agent"
        agent.verbose = False

        prompt = {"prompt": "Test {input}"}

        return {
            "llm": llm,
            "task": task,
            "crew": crew,
            "agent": agent,
            "prompt": prompt,
            "max_iter": 10,
            "tools": [],
            "tools_names": "",
            "stop_words": [],
            "tools_description": "",
            "tools_handler": Mock(),
        }

    @patch("crewai.experimental.agent_executor.get_llm_response")
    @patch("crewai.experimental.agent_executor.enforce_rpm_limit")
    def test_call_llm_parser_error(
        self, mock_enforce_rpm, mock_get_llm, mock_dependencies
    ):
        """Test call_llm_and_parse handles OutputParserError."""
        from crewai.agents.parser import OutputParserError

        mock_enforce_rpm.return_value = None
        mock_get_llm.side_effect = OutputParserError("parse failed")

        executor = AgentExecutor(**mock_dependencies)
        result = executor.call_llm_and_parse()

        assert result == "parser_error"
        assert executor._last_parser_error is not None

    @patch("crewai.experimental.agent_executor.get_llm_response")
    @patch("crewai.experimental.agent_executor.enforce_rpm_limit")
    @patch("crewai.experimental.agent_executor.is_context_length_exceeded")
    def test_call_llm_context_error(
        self,
        mock_is_context_exceeded,
        mock_enforce_rpm,
        mock_get_llm,
        mock_dependencies,
    ):
        """Test call_llm_and_parse handles context length error."""
        mock_enforce_rpm.return_value = None
        mock_get_llm.side_effect = Exception("context length")
        mock_is_context_exceeded.return_value = True

        executor = AgentExecutor(**mock_dependencies)
        result = executor.call_llm_and_parse()

        assert result == "context_error"
        assert executor._last_context_error is not None


class TestFlowInvoke:
    """Test the invoke method that maintains backward compatibility."""

    @pytest.fixture
    def mock_dependencies(self):
        """Create mock dependencies."""
        llm = Mock()
        task = Mock()
        task.description = "Test"
        task.human_input = False

        crew = Mock()
        crew._short_term_memory = None
        crew._long_term_memory = None
        crew._entity_memory = None
        crew._external_memory = None

        agent = Mock()
        agent.role = "Test"
        agent.verbose = False

        prompt = {"prompt": "Test {input} {tool_names} {tools}"}

        return {
            "llm": llm,
            "task": task,
            "crew": crew,
            "agent": agent,
            "prompt": prompt,
            "max_iter": 10,
            "tools": [],
            "tools_names": "",
            "stop_words": [],
            "tools_description": "",
            "tools_handler": Mock(),
        }

    @patch.object(AgentExecutor, "kickoff")
    @patch.object(AgentExecutor, "_create_short_term_memory")
    @patch.object(AgentExecutor, "_create_long_term_memory")
    @patch.object(AgentExecutor, "_create_external_memory")
    def test_invoke_success(
        self,
        mock_external_memory,
        mock_long_term_memory,
        mock_short_term_memory,
        mock_kickoff,
        mock_dependencies,
    ):
        """Test successful invoke without human feedback."""
        executor = AgentExecutor(**mock_dependencies)

        # Mock kickoff to set the final answer in state
        def mock_kickoff_side_effect():
            executor.state.current_answer = AgentFinish(
                thought="final thinking", output="Final result", text="complete"
            )

        mock_kickoff.side_effect = mock_kickoff_side_effect

        inputs = {"input": "test", "tool_names": "", "tools": ""}
        result = executor.invoke(inputs)

        assert result == {"output": "Final result"}
        mock_kickoff.assert_called_once()
        mock_short_term_memory.assert_called_once()
        mock_long_term_memory.assert_called_once()
        mock_external_memory.assert_called_once()

    @patch.object(AgentExecutor, "kickoff")
    def test_invoke_failure_no_agent_finish(self, mock_kickoff, mock_dependencies):
        """Test invoke fails without AgentFinish."""
        executor = AgentExecutor(**mock_dependencies)
        executor.state.current_answer = AgentAction(
            thought="thinking", tool="test", tool_input="test", text="action text"
        )

        inputs = {"input": "test", "tool_names": "", "tools": ""}

        with pytest.raises(RuntimeError, match="without reaching a final answer"):
            executor.invoke(inputs)

    @patch.object(AgentExecutor, "kickoff")
    @patch.object(AgentExecutor, "_create_short_term_memory")
    @patch.object(AgentExecutor, "_create_long_term_memory")
    @patch.object(AgentExecutor, "_create_external_memory")
    def test_invoke_with_system_prompt(
        self,
        mock_external_memory,
        mock_long_term_memory,
        mock_short_term_memory,
        mock_kickoff,
        mock_dependencies,
    ):
        """Test invoke with system prompt configuration."""
        mock_dependencies["prompt"] = {
            "system": "System: {input}",
            "user": "User: {input} {tool_names} {tools}",
        }
        executor = AgentExecutor(**mock_dependencies)

        def mock_kickoff_side_effect():
            executor.state.current_answer = AgentFinish(
                thought="final thoughts", output="Done", text="complete"
            )

        mock_kickoff.side_effect = mock_kickoff_side_effect

        inputs = {"input": "test", "tool_names": "", "tools": ""}
        result = executor.invoke(inputs)
        mock_short_term_memory.assert_called_once()
        mock_long_term_memory.assert_called_once()
        mock_external_memory.assert_called_once()
        mock_kickoff.assert_called_once()

        assert result == {"output": "Done"}
        assert len(executor.state.messages) >= 2


class TestAgentExecutorPlanning:
    """Test planning functionality in AgentExecutor with real agent kickoff."""

    @pytest.mark.vcr()
    def test_agent_kickoff_with_planning_stores_plan_in_state(self):
        """Test that Agent.kickoff() with planning enabled stores plan in executor state."""
        from crewai import Agent, PlanningConfig
        from crewai.llm import LLM

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Math Assistant",
            goal="Help solve simple math problems",
            backstory="A helpful assistant that solves math problems step by step",
            llm=llm,
            planning_config=PlanningConfig(max_attempts=1),
            verbose=False,
        )

        # Execute kickoff with a simple task
        result = agent.kickoff("What is 2 + 2?")

        # Verify result
        assert result is not None
        assert "4" in str(result)

    @pytest.mark.vcr()
    def test_agent_kickoff_without_planning_skips_plan_generation(self):
        """Test that Agent.kickoff() without planning skips planning phase."""
        from crewai import Agent
        from crewai.llm import LLM

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Math Assistant",
            goal="Help solve simple math problems",
            backstory="A helpful assistant",
            llm=llm,
            # No planning_config = no planning
            verbose=False,
        )

        # Execute kickoff
        result = agent.kickoff("What is 3 + 3?")

        # Verify we get a result
        assert result is not None
        assert "6" in str(result)

    @pytest.mark.vcr()
    def test_planning_disabled_skips_planning(self):
        """Test that planning=False skips planning."""
        from crewai import Agent
        from crewai.llm import LLM

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Math Assistant",
            goal="Help solve simple math problems",
            backstory="A helpful assistant",
            llm=llm,
            planning=False,  # Explicitly disable planning
            verbose=False,
        )

        result = agent.kickoff("What is 5 + 5?")

        # Should still complete successfully
        assert result is not None
        assert "10" in str(result)

    def test_backward_compat_reasoning_true_enables_planning(self):
        """Test that reasoning=True (deprecated) still enables planning."""
        import warnings
        from crewai import Agent
        from crewai.llm import LLM

        llm = LLM("gpt-4o-mini")

        with warnings.catch_warnings(record=True):
            warnings.simplefilter("always")
            agent = Agent(
                role="Test Agent",
                goal="Complete tasks",
                backstory="A helpful agent",
                llm=llm,
                reasoning=True,  # Deprecated but should still work
                verbose=False,
            )

        # Should have planning_config created from reasoning=True
        assert agent.planning_config is not None
        assert agent.planning_enabled is True

    @pytest.mark.vcr()
    def test_executor_state_contains_plan_after_planning(self):
        """Test that executor state contains plan after planning phase."""
        from crewai import Agent, PlanningConfig
        from crewai.llm import LLM
        from crewai.experimental.agent_executor import AgentExecutor

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Math Assistant",
            goal="Help solve simple math problems",
            backstory="A helpful assistant that solves math problems step by step",
            llm=llm,
            planning_config=PlanningConfig(max_attempts=1),
            verbose=False,
        )

        # Track executor for inspection
        executor_ref = [None]
        original_invoke = AgentExecutor.invoke

        def capture_executor(self, inputs):
            executor_ref[0] = self
            return original_invoke(self, inputs)

        with patch.object(AgentExecutor, "invoke", capture_executor):
            result = agent.kickoff("What is 7 + 7?")

        # Verify result
        assert result is not None

        # If we captured an executor, check its state
        if executor_ref[0] is not None:
            # After planning, state should have plan info
            assert hasattr(executor_ref[0].state, "plan")
            assert hasattr(executor_ref[0].state, "plan_ready")

    @pytest.mark.vcr()
    def test_planning_creates_minimal_steps_for_multi_step_task(self):
        """Test that planning creates steps and executes them for a multi-step task.

        This task requires multiple dependent steps:
        1. Identify the first 3 prime numbers (2, 3, 5)
        2. Sum them (2 + 3 + 5 = 10)
        3. Multiply by 2 (10 * 2 = 20)

        The plan-and-execute architecture should produce step results.
        """
        from crewai import Agent, PlanningConfig
        from crewai.llm import LLM
        from crewai.experimental.agent_executor import AgentExecutor

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Math Tutor",
            goal="Solve multi-step math problems accurately",
            backstory="An expert math tutor who breaks down problems step by step",
            llm=llm,
            planning_config=PlanningConfig(max_attempts=1, max_steps=10),
            verbose=False,
        )

        # Track the plan that gets generated
        captured_plan = [None]
        original_invoke = AgentExecutor.invoke

        def capture_plan(self, inputs):
            result = original_invoke(self, inputs)
            captured_plan[0] = self.state.plan
            return result

        with patch.object(AgentExecutor, "invoke", capture_plan):
            result = agent.kickoff(
                "Calculate the sum of the first 3 prime numbers, then multiply that result by 2. "
                "Show your work for each step."
            )

        # Verify we got a result with step outputs
        assert result is not None
        result_str = str(result)
        # Should contain at least some mathematical content from the steps
        assert "prime" in result_str.lower() or "2" in result_str or "10" in result_str

        # Verify a plan was generated
        assert captured_plan[0] is not None

    @pytest.mark.vcr()
    def test_planning_handles_sequential_dependency_task(self):
        """Test planning for a task where step N depends on step N-1.

        Task: Convert 100 Celsius to Fahrenheit, then round to nearest 10.
        Step 1: Apply formula (C * 9/5 + 32) = 212
        Step 2: Round 212 to nearest 10 = 210

        This tests that the planner creates a plan and executes steps.
        """
        from crewai import Agent, PlanningConfig
        from crewai.llm import LLM
        from crewai.experimental.agent_executor import AgentExecutor

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Unit Converter",
            goal="Accurately convert between units and apply transformations",
            backstory="A precise unit conversion specialist",
            llm=llm,
            planning_config=PlanningConfig(max_attempts=1, max_steps=10),
            verbose=False,
        )

        captured_plan = [None]
        original_invoke = AgentExecutor.invoke

        def capture_plan(self, inputs):
            result = original_invoke(self, inputs)
            captured_plan[0] = self.state.plan
            return result

        with patch.object(AgentExecutor, "invoke", capture_plan):
            result = agent.kickoff(
                "Convert 100 degrees Celsius to Fahrenheit, then round the result to the nearest 10."
            )

        assert result is not None
        result_str = str(result)
        # Should contain conversion-related content
        assert "212" in result_str or "210" in result_str or "Fahrenheit" in result_str or "celsius" in result_str.lower()

        # Plan should exist
        assert captured_plan[0] is not None


class TestResponseFormatWithKickoff:
    """Test that Agent.kickoff(response_format=MyModel) returns structured output.

    Real LLM calls via VCR cassettes. Tests both with and without planning,
    using real tools for the planning case to exercise the full Plan-and-Execute
    path including synthesis with response_model.
    """

    @pytest.mark.vcr()
    def test_kickoff_response_format_without_planning(self):
        """Test that kickoff(response_format) returns structured output without planning."""
        from pydantic import BaseModel, Field
        from crewai import Agent
        from crewai.llm import LLM

        class MathResult(BaseModel):
            answer: int = Field(description="The numeric answer")
            explanation: str = Field(description="Brief explanation of the solution")

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Math Assistant",
            goal="Solve math problems and return structured results",
            backstory="A precise math assistant that always returns structured data",
            llm=llm,
            verbose=False,
        )

        result = agent.kickoff("What is 15 + 27?", response_format=MathResult)

        assert result is not None
        assert result.pydantic is not None
        assert isinstance(result.pydantic, MathResult)
        assert result.pydantic.answer == 42
        assert len(result.pydantic.explanation) > 0

    @pytest.mark.vcr()
    def test_kickoff_response_format_with_planning_and_tools(self):
        """Test response_format with planning + tools (multi-step research).

        This is the key test for _synthesize_final_answer_from_todos:
        1. Planning generates steps that use the EXA search tool
        2. StepExecutor runs each step in isolation with tool calls
        3. The synthesis step produces a structured BaseModel output

        The response_format should be respected by the synthesis LLM call,
        NOT by intermediate step executions.
        """
        from pydantic import BaseModel, Field
        from crewai import Agent, PlanningConfig
        from crewai.llm import LLM
        from crewai_tools import EXASearchTool

        class ResearchSummary(BaseModel):
            topic: str = Field(description="The research topic")
            key_findings: list[str] = Field(description="List of 3-5 key findings")
            conclusion: str = Field(description="A brief conclusion paragraph")

        llm = LLM("gpt-4o-mini")
        exa = EXASearchTool()

        agent = Agent(
            role="Research Analyst",
            goal="Research topics using search tools and produce structured summaries",
            backstory=(
                "You are a research analyst who searches the web for information, "
                "identifies key findings, and produces structured research summaries."
            ),
            llm=llm,
            planning_config=PlanningConfig(max_attempts=1, max_steps=5),
            tools=[exa],
            verbose=False,
        )

        result = agent.kickoff(
            "Research the current state of autonomous AI agents in 2025. "
            "Search for recent developments, then summarize the key findings.",
            response_format=ResearchSummary,
        )

        assert result is not None
        # The synthesis step should have produced structured output
        assert result.pydantic is not None
        assert isinstance(result.pydantic, ResearchSummary)
        # Verify the structured fields are populated
        assert len(result.pydantic.topic) > 0
        assert len(result.pydantic.key_findings) >= 1
        assert len(result.pydantic.conclusion) > 0

    @pytest.mark.vcr()
    def test_kickoff_no_response_format_returns_raw_text(self):
        """Test that kickoff without response_format returns plain text."""
        from crewai import Agent
        from crewai.llm import LLM

        llm = LLM("gpt-4o-mini")

        agent = Agent(
            role="Math Assistant",
            goal="Solve math problems",
            backstory="A helpful math assistant",
            llm=llm,
            verbose=False,
        )

        result = agent.kickoff("What is 10 + 10?")

        assert result is not None
        assert result.pydantic is None
        assert "20" in str(result)