A Comprehensive Tutorial on the Five Levels of Agentic AI Architectures: From Basic Prompt Responses to Fully Autonomous Code Generation and Execution

import os
import torch
from transformers import pipeline, AutoTokenizer, AutoModelForCausalLM
import re
import json
import time
import random
from IPython.display import clear_output

MODEL_NAME = "TinyLlama/TinyLlama-1.1B-Chat-v1.0"
def get_model_and_tokenizer():
    if not hasattr(get_model_and_tokenizer, "model"):
        print(f"Loading model {MODEL_NAME}...")
        tokenizer = AutoTokenizer.from_pretrained(MODEL_NAME)
        model = AutoModelForCausalLM.from_pretrained(
            MODEL_NAME,
            torch_dtype=torch.float16,
            device_map="auto",
            low_cpu_mem_usage=True
        )
        get_model_and_tokenizer.model = model
        get_model_and_tokenizer.tokenizer = tokenizer
        print("Model loaded successfully!")
   
    return get_model_and_tokenizer.model, get_model_and_tokenizer.tokenizer

def get_model_and_tokenizer():
    if not hasattr(get_model_and_tokenizer, "model"):
        print(f"Loading model {MODEL_NAME}...")
        tokenizer = AutoTokenizer.from_pretrained(MODEL_NAME)
        model = AutoModelForCausalLM.from_pretrained(
            MODEL_NAME,
            torch_dtype=torch.float16,
            device_map="auto",
            low_cpu_mem_usage=True
        )
        get_model_and_tokenizer.model = model
        get_model_and_tokenizer.tokenizer = tokenizer
        print("Model loaded successfully!")
   
    return get_model_and_tokenizer.model, get_model_and_tokenizer.tokenizer

def generate_text(prompt, max_length=512):
    model, tokenizer = get_model_and_tokenizer()
   
    messages = [{"role": "user", "content": prompt}]
    formatted_prompt = tokenizer.apply_chat_template(messages, tokenize=False)
   
    inputs = tokenizer(formatted_prompt, return_tensors="pt").to(model.device)
   
    with torch.no_grad():
        output = model.generate(
            **inputs,
            max_new_tokens=max_length,
            do_sample=True,
            temperature=0.7,
            top_p=0.9,
        )
   
    generated_text = tokenizer.decode(output[0], skip_special_tokens=True)
   
    response = generated_text.split("ASSISTANT: ")[-1].strip()
    return response

def simple_processor(prompt):
    """Level 1: Simple Processor - Model has no impact on program flow"""
    response = generate_text(prompt)
    return response


def demo_level1():
    print("\n" + "="*50)
    print("LEVEL 1: SIMPLE PROCESSOR DEMO")
    print("="*50)
    print("At this level, the AI has no control over program flow.")
    print("It simply takes input and produces output.\n")
   
    user_input = input("Enter your question or prompt: ") or "Write a short poem about artificial intelligence."
    print("\nProcessing your request...\n")
   
    output = simple_processor(user_input)
    print("OUTPUT:")
    print("-"*50)
    print(output)
    print("-"*50)

def router_agent(user_query):
    """Level 2: Router - Model determines basic program flow"""
   
    category_prompt = f"""Classify the following query into one of these categories:
    'technical', 'creative', or 'factual'.
   
    Query: {user_query}
   
    Return ONLY the category name and nothing else."""
   
    category_response = generate_text(category_prompt)
   
    category = category_response.lower()
    if "technical" in category:
        category = "technical"
    elif "creative" in category:
        category = "creative"
    else:
        category = "factual"
   
    print(f"Query classified as: {category}")
   
    if category == "technical":
        return handle_technical_query(user_query)
    elif category == "creative":
        return handle_creative_query(user_query)
    else:  
        return handle_factual_query(user_query)


def handle_technical_query(query):
    system_prompt = f"""You are a technical assistant. Provide detailed technical explanations.
   
    User query: {query}"""
   
    response = generate_text(system_prompt)
    return f"[Technical Response]\n{response}"


def handle_creative_query(query):
    system_prompt = f"""You are a creative assistant. Be imaginative and inspiring.
   
    User query: {query}"""
   
    response = generate_text(system_prompt)
    return f"[Creative Response]\n{response}"


def handle_factual_query(query):
    system_prompt = f"""You are a factual assistant. Provide accurate information concisely.
   
    User query: {query}"""
   
    response = generate_text(system_prompt)
    return f"[Factual Response]\n{response}"


def demo_level2():
    print("\n" + "="*50)
    print("LEVEL 2: ROUTER DEMO")
    print("="*50)
    print("At this level, the AI determines basic program flow.")
    print("It decides which processing path to take.\n")
   
    user_query = input("Enter your question or prompt: ") or "How do neural networks work?"
    print("\nProcessing your request...\n")
   
    result = router_agent(user_query)
    print("OUTPUT:")
    print("-"*50)
    print(result)
    print("-"*50)

def tool_calling_agent(user_query):
    """Level 3: Tool Calling - Model determines how functions are executed"""
   
    tool_selection_prompt = f"""Based on the user query, select the most appropriate tool from the following list:
    1. get_weather: Get the current weather for a location
    2. search_information: Search for specific information on a topic
    3. get_date_time: Get current date and time
    4. direct_response: Provide a direct response without using tools
   
    USER QUERY: {user_query}
   
    INSTRUCTIONS:
    - Return your response in valid JSON format
    - Include the tool name and any required parameters
    - For get_weather, include location parameter
    - For search_information, include query and depth parameter (basic or detailed)
    - For get_date_time, include timezone parameter (optional)
    - For direct_response, no parameters needed
   
    Example output format: {{"tool": "get_weather", "parameters": {{"location": "New York"}}}}"""
   
    tool_selection_response = generate_text(tool_selection_prompt)
   
    try:
        json_match = re.search(r'({.*})', tool_selection_response, re.DOTALL)
        if json_match:
            tool_selection = json.loads(json_match.group(1))
        else:
            print("Could not parse tool selection. Defaulting to direct response.")
            tool_selection = {"tool": "direct_response", "parameters": {}}
    except json.JSONDecodeError:
        print("Invalid JSON in tool selection. Defaulting to direct response.")
        tool_selection = {"tool": "direct_response", "parameters": {}}
   
    tool_name = tool_selection.get("tool", "direct_response")
    parameters = tool_selection.get("parameters", {})
   
    print(f"Selected tool: {tool_name}")
   
    if tool_name == "get_weather":
        location = parameters.get("location", "Unknown")
        tool_result = get_weather(location)
    elif tool_name == "search_information":
        query = parameters.get("query", user_query)
        depth = parameters.get("depth", "basic")
        tool_result = search_information(query, depth)
    elif tool_name == "get_date_time":
        timezone = parameters.get("timezone", "UTC")
        tool_result = get_date_time(timezone)
    else:
        return generate_text(f"Please provide a helpful response to: {user_query}")
   
    final_prompt = f"""User Query: {user_query}
    Tool Used: {tool_name}
    Tool Result: {json.dumps(tool_result)}
   
    Based on the user's query and the tool result above, provide a helpful response."""
   
    final_response = generate_text(final_prompt)
    return final_response


def get_weather(location):
    weather_conditions = ["Sunny", "Partly cloudy", "Overcast", "Light rain", "Heavy rain", "Thunderstorms", "Snowy", "Foggy"]
    temperatures = {
        "cold": list(range(-10, 10)),
        "mild": list(range(10, 25)),
        "hot": list(range(25, 40))
    }
   
    location_hash = sum(ord(c) for c in location)
    condition_index = location_hash % len(weather_conditions)
    season = ["winter", "spring", "summer", "fall"][location_hash % 4]
   
    temp_range = temperatures["cold"] if season in ["winter", "fall"] else temperatures["hot"] if season == "summer" else temperatures["mild"]
    temperature = random.choice(temp_range)
   
    return {
        "location": location,
        "temperature": f"{temperature}°C",
        "conditions": weather_conditions[condition_index],
        "humidity": f"{random.randint(30, 90)}%"
    }


def search_information(query, depth="basic"):
    mock_results = [
        f"First result about {query}",
        f"Second result discussing {query}",
        f"Third result analyzing {query}"
    ]
   
    if depth == "detailed":
        mock_results.extend([
            f"Fourth detailed analysis of {query}",
            f"Fifth comprehensive overview of {query}",
            f"Sixth academic paper on {query}"
        ])
   
    return {
        "query": query,
        "results": mock_results,
        "depth": depth,
        "sources": [f"source{i}.com" for i in range(1, len(mock_results) + 1)]
    }


def get_date_time(timezone="UTC"):
    current_time = time.strftime("%Y-%m-%d %H:%M:%S", time.gmtime())
    return {
        "current_datetime": current_time,
        "timezone": timezone
    }


def demo_level3():
    print("\n" + "="*50)
    print("LEVEL 3: TOOL CALLING DEMO")
    print("="*50)
    print("At this level, the AI selects which tools to use and with what parameters.")
    print("It can process the results from tools to create a final response.\n")
   
    user_query = input("Enter your question or prompt: ") or "What's the weather like in San Francisco?"
    print("\nProcessing your request...\n")
   
    result = tool_calling_agent(user_query)
    print("OUTPUT:")
    print("-"*50)
    print(result)
    print("-"*50)

class MultiStepAgent:
    """Level 4: Multi-Step Agent - Model controls iteration and program continuation"""
   
    def __init__(self):
        self.tools = {
            "search_web": self.search_web,
            "extract_info": self.extract_info,
            "summarize_text": self.summarize_text,
            "create_report": self.create_report
        }
        self.memory = []
        self.max_steps = 5
   
    def run(self, user_task):
        self.memory.append({"role": "user", "content": user_task})
       
        steps_taken = 0
        while steps_taken < self.max_steps:
            next_action = self.determine_next_action()
           
            if next_action["action"] == "complete":
                return next_action["output"]
           
            tool_name = next_action["tool"]
            tool_args = next_action["args"]
           
            print(f"\n📌 Step {steps_taken + 1}: Using tool '{tool_name}' with arguments: {tool_args}")
           
            tool_result = self.tools[tool_name](**tool_args)
           
            self.memory.append({
                "role": "tool",
                "content": json.dumps(tool_result)
            })
           
            steps_taken += 1
       
        return self.generate_final_response("Maximum steps reached. Here's what I've found so far.")
   
    def determine_next_action(self):
        context = "Current memory state:\n"
        for item in self.memory:
            if item["role"] == "user":
                context += f"USER INPUT: {item['content']}\n\n"
            elif item["role"] == "tool":
                context += f"TOOL RESULT: {item['content']}\n\n"
       
        prompt = f"""{context}
       
        Based on the above information, determine the next action to take.
        Choose one of the following options:
        1. search_web: Search for information (args: query)
        2. extract_info: Extract specific information from a text (args: text, target_info)
        3. summarize_text: Create a summary of text (args: text)
        4. create_report: Create a structured report (args: title, content)
        5. complete: Task is complete (include final output)
       
        Respond with a JSON object with the following structure:
        For tools: {{"action": "tool", "tool": "tool_name", "args": {{tool-specific arguments}}}}
        For completion: {{"action": "complete", "output": "final output text"}}
       
        Only return the JSON object and nothing else."""
       
        next_action_response = generate_text(prompt)
       
        try:
            json_match = re.search(r'({.*})', next_action_response, re.DOTALL)
            if json_match:
                next_action = json.loads(json_match.group(1))
            else:
                return {"action": "complete", "output": "I encountered an error in planning. Here's what I know so far: " + self.generate_final_response("Error in planning")}
        except json.JSONDecodeError:
            return {"action": "complete", "output": "I encountered an error in planning. Here's what I know so far: " + self.generate_final_response("Error in planning")}
           
        self.memory.append({"role": "assistant", "content": next_action_response})
        return next_action
   
    def generate_final_response(self, prefix=""):
        context = "Task history:\n"
        for item in self.memory:
            if item["role"] == "user":
                context += f"USER INPUT: {item['content']}\n\n"
            elif item["role"] == "tool":
                context += f"TOOL RESULT: {item['content']}\n\n"
            elif item["role"] == "assistant":
                context += f"AGENT ACTION: {item['content']}\n\n"
       
        prompt = f"""{context}
       
        {prefix} Generate a comprehensive final response that addresses the original user task."""
       
        final_response = generate_text(prompt)
        return final_response
   
    def search_web(self, query):
        time.sleep(1)  
       
        query_hash = sum(ord(c) for c in query)
        num_results = (query_hash % 3) + 2
       
        results = []
        for i in range(num_results):
            results.append(f"Result {i+1}: Information about '{query}' related to aspect {chr(97 + i)}.")
       
        return {
            "query": query,
            "results": results
        }
   
    def extract_info(self, text, target_info):
        time.sleep(0.5)  
       
        return {
            "extracted_info": f"Extracted information about '{target_info}' from the text: The text indicates that {target_info} is related to several key aspects mentioned in the content.",
            "confidence": round(random.uniform(0.7, 0.95), 2)
        }
   
    def summarize_text(self, text):
        time.sleep(0.5)
       
        word_count = len(text.split())
       
        return {
            "summary": f"Summary of the provided text ({word_count} words): The text discusses key points related to the subject matter, highlighting important aspects and providing context.",
            "original_length": word_count,
            "summary_length": round(word_count * 0.3)
        }
   
    def create_report(self, title, content):
        time.sleep(0.7)
       
        report_sections = [
            "## Introduction",
            f"This report provides an overview of {title}.",
            "",
            "## Key Findings",
            content,
            "",
            "## Conclusion",
            f"This analysis of {title} highlights several important aspects that warrant consideration."
        ]
       
        return {
            "report": "\n".join(report_sections),
            "word_count": len(content.split()),
            "section_count": 3
        }


def demo_level4():
    print("\n" + "="*50)
    print("LEVEL 4: MULTI-STEP AGENT DEMO")
    print("="*50)
    print("At this level, the AI manages the entire workflow, deciding which tools")
    print("to use, when to use them, and determining when the task is complete.\n")
   
    user_task = input("Enter a research or analysis task: ") or "Research quantum computing recent developments and create a brief report"
    print("\nProcessing your request... (this may take a minute)\n")
   
    agent = MultiStepAgent()
    result = agent.run(user_task)
    print("\nFINAL OUTPUT:")
    print("-"*50)
    print(result)
    print("-"*50)

class AutonomousAgent:
    """Level 5: Fully Autonomous Agent - Model creates & executes new code"""
   
    def __init__(self):
        self.memory = []
   
    def run(self, user_task):
        self.memory.append({"role": "user", "content": user_task})
       
        print("🧠 Planning solution approach...")
        planning_message = self.plan_solution(user_task)
        self.memory.append({"role": "assistant", "content": planning_message})
       
        print("💻 Generating solution code...")
        generated_code = self.generate_solution_code()
        self.memory.append({"role": "assistant", "content": f"Generated code: ```python\n{generated_code}\n```"})
       
        print("🔍 Validating code...")
        validation_result = self.validate_code(generated_code)
        if not validation_result["valid"]:
            print("⚠️ Code validation found issues - refining...")
            refined_code = self.refine_code(generated_code, validation_result["issues"])
            self.memory.append({"role": "assistant", "content": f"Refined code: ```python\n{refined_code}\n```"})
            generated_code = refined_code
        else:
            print("✅ Code validation passed")
       
        try:
            print("🚀 Executing solution...")
            execution_result = self.safe_execute_code(generated_code, user_task)
            self.memory.append({"role": "system", "content": f"Execution result: {execution_result}"})
           
            # Generate a final report
            print("📝 Creating final report...")
            final_report = self.create_final_report(execution_result)
            return final_report
           
        except Exception as e:
            return f"Error executing the solution: {str(e)}\n\nGenerated code was:\n```python\n{generated_code}\n```"
   
    def plan_solution(self, task):
        prompt = f"""Task: {task}


        You are an autonomous problem-solving agent. Create a detailed plan to solve this task.
        Include:
        1. Breaking down the task into subtasks
        2. What algorithms or approaches you'll use
        3. What data structures are needed
        4. Any external resources or libraries required
        5. Expected challenges and how to address them


        Provide a step-by-step plan.
        """
       
        return generate_text(prompt)
   
    def generate_solution_code(self):
        context = "Task and planning information:\n"
        for item in self.memory:
            if item["role"] == "user":
                context += f"USER TASK: {item['content']}\n\n"
            elif item["role"] == "assistant":
                context += f"PLANNING: {item['content']}\n\n"
       
        prompt = f"""{context}


        Generate clean, efficient Python code that solves this task. Include comments to explain the code.
        The code should be self-contained and able to run inside a Python script or notebook.
        Only include the Python code itself without any markdown formatting.
        """
       
        code = generate_text(prompt)
       
        code = re.sub(r'^```python\n|```$', '', code, flags=re.MULTILINE)
       
        return code
   
    def validate_code(self, code):
        prompt = f"""Code to validate:
        ```python
        {code}
        ```


        Examine the code for the following issues:
        1. Syntax errors
        2. Logic errors
        3. Inefficient implementations
        4. Security concerns
        5. Missing error handling
        6. Import statements for unavailable libraries


        If the code has any issues, describe them in detail. If the code looks good, state "No issues found."
        """
       
        validation_response = generate_text(prompt)
       
        if "no issues" in validation_response.lower() or "code looks good" in validation_response.lower():
            return {"valid": True, "issues": None}
        else:
            return {"valid": False, "issues": validation_response}
   
    def refine_code(self, original_code, issues):
        prompt = f"""Original code:
        ```python
        {original_code}
        ```


        Issues identified:
        {issues}


        Please provide a corrected version of the code that addresses these issues.
        Only include the Python code itself without any markdown formatting.
        """
       
        refined_code = generate_text(prompt)
       
        refined_code = re.sub(r'^```python\n|```$', '', refined_code, flags=re.MULTILINE)
       
        return refined_code
   


    def safe_execute_code(self, code, user_task):
       
        safe_imports = """
    # Standard library imports
    import math
    import random
    import re
    import time
    import json
    from datetime import datetime


    # Define a function to capture printed output
    captured_output = []
    original_print = print


    def safe_print(*args, **kwargs):
        output = " ".join(str(arg) for arg in args)
        captured_output.append(output)
        original_print(output)
       
    print = safe_print


    # Define a result variable to store the final output
    result = None


    # Function to store the final result
    def store_result(value):
        global result
        result = value
        return value
    """
       
        result_capture = """
    # Store the final result if not already done
    if 'result' not in locals() or result is None:
        try:
            # Look for variables that might contain the final result
            potential_results = [var for var in locals() if not var.startswith('_') and var not in
                                ['math', 'random', 're', 'time', 'json', 'datetime',
                                'captured_output', 'original_print', 'safe_print',
                                'result', 'store_result']]
            if potential_results:
                # Use the last defined variable as the result
                store_result(locals()[potential_results[-1]])
        except:
            pass
    """
       
        full_code = safe_imports + "\n# User code starts here\n" + code + "\n\n" + result_capture
       
        code_lines = code.split('\n')
        first_lines = code_lines[:3]
        print(f"\nExecuting (first 3 lines):\n{first_lines}")
       
        local_env = {}
       
        try:
            exec(full_code, {}, local_env)
           
            return {
                "output": local_env.get('captured_output', []),
                "result": local_env.get('result', "No explicit result returned")
            }
        except Exception as e:
            return {"error": str(e)}
       
    def create_final_report(self, execution_result):
        if isinstance(execution_result.get('output'), list):
            output_text = "\n".join(execution_result.get('output', []))
        else:
            output_text = str(execution_result.get('output', ''))
       
        result_text = str(execution_result.get('result', ''))
        error_text = execution_result.get('error', '')
       
        context = "Task history:\n"
        for item in self.memory:
            if item["role"] == "user":
                context += f"USER TASK: {item['content']}\n\n"
       
        prompt = f"""{context}
       
        EXECUTION OUTPUT:
        {output_text}
       
        EXECUTION RESULT:
        {result_text}
       
        {f"ERROR: {error_text}" if error_text else ""}
       
        Create a final report that explains the solution to the original task. Include:
        1. What was done
        2. How it was accomplished
        3. The final results
        4. Any insights or conclusions drawn from the analysis
       
        Format the report in a professional, easy to read manner.
        """
       
        return generate_text(prompt)


def demo_level5():
    print("\n" + "="*50)
    print("LEVEL 5: FULLY AUTONOMOUS AGENT DEMO")
    print("="*50)
    print("At this level, the AI generates and executes code to solve complex problems.")
    print("It can create, validate, refine, and run custom code solutions.\n")
   
    user_task = input("Enter a data analysis or computational task: ") or "Analyze a dataset of numbers [10, 45, 65, 23, 76, 12, 89, 32, 50] and create visualizations of the distribution"
    print("\nProcessing your request... (this may take a minute or two)\n")
   
    agent = AutonomousAgent()
    result = agent.run(user_task)
    print("\nFINAL REPORT:")
    print("-"*50)
    print(result)
    print("-"*50)

def main():
    while True:
        clear_output(wait=True)
        print("\n" + "="*50)
        print("AI AGENT LEVELS DEMO")
        print("="*50)
        print("\nThis notebook demonstrates the 5 levels of AI agents:")
        print("1. Simple Processor - Model has no impact on program flow")
        print("2. Router - Model determines basic program flow")
        print("3. Tool Calling - Model determines how functions are executed")
        print("4. Multi-Step Agent - Model controls iteration and program continuation")
        print("5. Fully Autonomous Agent - Model creates & executes new code")
        print("6. Quit")
       
        choice = input("\nSelect a level to demo (1-6): ")
       
        if choice == "1":
            demo_level1()
        elif choice == "2":
            demo_level2()
        elif choice == "3":
            demo_level3()
        elif choice == "4":
            demo_level4()
        elif choice == "5":
            demo_level5()
        elif choice == "6":
            print("\nThank you for exploring the AI Agent levels!")
            break
        else:
            print("\nInvalid choice. Please select 1-6.")
       
        input("\nPress Enter to return to the main menu...")


if __name__ == "__main__":
    main()