How agents think
Understanding reasoning, memory, and decision-making in AI agents
How Agents Think
πΆ Explained like I'm 5
Imagine you're playing a puzzle game. You don't just randomly try pieces - you:
- Look at what you have
- Think about what piece might fit
- Try it
- See if it works
- If not, try something else
AI agents think the same way! They:
- Look at the problem
- Think about what to do
- Try doing it
- See what happens
- Decide what to do next
Thinking vs Acting
Thinking is the planning phase. Acting is the execution. Good thinking leads to better actions.
β Why we need this
For agents to be useful, they need to:
- Reason: Think through problems step by step
- Remember: Keep track of what they've learned
- Decide: Choose the best action to take
- Learn: Get better from experience
Without thinking, agents would just be random - like a robot throwing darts blindfolded!
π§ How it works
Reasoning
Agents use something called "chain of thought" reasoning:
Problem: "Find the best pizza place nearby"
Step 1: I need to know the user's location
Step 2: Search for pizza places in that area
Step 3: Check reviews and ratings
Step 4: Compare prices
Step 5: Recommend the best option
Memory
Agents remember things in different ways:
- Short-term: What happened in this conversation
- Long-term: Important facts learned over time
- Working memory: What they're thinking about right now
Decision Making
Agents decide what to do by:
- Looking at their goal
- Checking what tools they have
- Remembering what worked before
- Choosing the best action
π Deep Dive: Reasoning Mechanisms
1. Chain of Thought Reasoning
Chain of thought breaks complex problems into smaller steps:
βββββββββββββββββββββββββββββββββββ
β Complex Problem β
ββββββββββββββ¬βββββββββββββββββββββ
β
βΌ
ββββββββββββββββββ
β Step 1 β
β Understand β
ββββββββββ¬ββββββββ
β
βΌ
ββββββββββββββββββ
β Step 2 β
β Plan β
ββββββββββ¬ββββββββ
β
βΌ
ββββββββββββββββββ
β Step 3 β
β Execute β
ββββββββββ¬ββββββββ
β
βΌ
ββββββββββββββββββ
β Step 4 β
β Evaluate β
ββββββββββββββββββ
Example in Code:
# Agent reasoning process
def agent_reason(problem):
# Step 1: Understand
understanding = analyze_problem(problem)
# Step 2: Plan
plan = create_plan(understanding)
# Step 3: Execute
result = execute_plan(plan)
# Step 4: Evaluate
if evaluate_result(result):
return result
else:
# Re-plan if needed
return agent_reason(refined_problem)
2. ReAct Pattern (Reasoning + Acting)
The ReAct pattern combines reasoning and acting:
ββββββββββββ ββββββββββββ ββββββββββββ
β THINK β --> β ACT β --> β OBSERVE β
β β β β β β
β "What β β Execute β β "What β
β should β β action β β happenedβ
β I do?" β β β β ?" β
ββββββ¬ββββββ ββββββ¬ββββββ ββββββ¬ββββββ
β β β
ββββββββββββββββββ΄βββββββββββββββββ
Loop until goal achieved
Code Example:
from crewai import Agent
agent = Agent(
role='Problem Solver',
goal='Solve complex problems step by step',
backstory='You think carefully before acting',
verbose=True
)
# The agent automatically uses ReAct pattern:
# 1. Thinks about what to do
# 2. Takes action
# 3. Observes results
# 4. Repeats until done
3. Memory Systems
Short-Term Memory (Conversation Context)
Stores information about the current interaction:
# Example: Conversation memory
conversation_memory = {
"user_query": "Find restaurants",
"location": "New York",
"preferences": ["Italian", "Vegetarian"],
"previous_results": [...]
}
Long-Term Memory (Persistent Storage)
Stores information across sessions:
# Example: Long-term memory
long_term_memory = {
"user_preferences": {
"favorite_cuisines": ["Italian", "Japanese"],
"budget_range": "$20-50",
"dietary_restrictions": ["Vegetarian"]
},
"learned_patterns": {
"best_search_times": "Evening",
"preferred_rating": "4+ stars"
}
}
Working Memory (Active Processing)
What the agent is currently thinking about:
# Example: Working memory
working_memory = {
"current_goal": "Find restaurant",
"active_tools": ["search", "filter"],
"pending_tasks": ["check_reviews", "compare_prices"],
"decision_point": "Which restaurant to recommend?"
}
π§ͺ Example
Let's see an agent planning a party:
Goal: Plan a birthday party
Agent thinks:
1. "I need to know: date, number of guests, budget"
2. "Let me ask the user for this info"
3. "Now I'll search for venues"
4. "Compare prices and availability"
5. "Check what decorations are needed"
6. "Create a shopping list"
7. "Send reminders to the user"
Agent acts:
- Asks questions
- Searches the web
- Uses calendar tools
- Creates lists
- Sends notifications
Detailed Example: Research Agent Reasoning
from crewai import Agent, Task, Crew
from crewai.tools import DuckDuckGoSearchRun
# Create agent with reasoning capabilities
researcher = Agent(
role='Research Specialist',
goal='Find accurate, comprehensive information',
backstory='You think systematically and verify information',
tools=[DuckDuckGoSearchRun()],
memory=True, # Enable memory
verbose=True
)
# Task that requires reasoning
research_task = Task(
description='''
Research the impact of AI on healthcare.
Reasoning steps:
1. Search for recent articles (last 2 years)
2. Identify key themes and trends
3. Find statistics and data
4. Identify expert opinions
5. Synthesize findings into a comprehensive summary
Expected output: A 500-word summary with key findings, statistics, and trends.
''',
agent=researcher
)
crew = Crew(agents=[researcher], tasks=[research_task])
result = crew.kickoff()
What happens internally:
- Reasoning Phase: Agent breaks down the task into steps
- Planning Phase: Determines search queries and approach
- Execution Phase: Performs searches and gathers information
- Analysis Phase: Processes and synthesizes findings
- Verification Phase: Checks completeness and quality
- Output Phase: Formats and presents results
π― Real-World Case Studies
Financial Analysis Agent with Advanced Reasoning
π Scenario
A financial analyst needs to analyze market trends, but manual analysis takes days and is error-prone.
π‘ Solution
Built an agent with multi-step reasoning: (1) Gather market data from multiple sources, (2) Analyze trends using statistical methods, (3) Compare against historical patterns, (4) Identify anomalies, (5) Generate insights with confidence scores. The agent uses chain-of-thought reasoning to break down complex analysis.
β Outcome
Analysis time reduced from 3 days to 2 hours. Accuracy improved by 40%. Agent identifies patterns humans miss. Reports include reasoning trail for transparency.
π Key Lessons
- Chain-of-thought reasoning improves accuracy
- Multi-step reasoning handles complex tasks
- Memory helps agents learn from past analyses
- Transparent reasoning builds trust
Customer Service Agent with Context Memory
π Scenario
Customers get frustrated repeating information to different support agents. Each interaction starts from scratch.
π‘ Solution
Implemented an agent with long-term memory that remembers customer preferences, past issues, and interaction history. The agent uses this context to provide personalized service and avoid asking for information already known.
β Outcome
Customer satisfaction increased by 50%. Average resolution time reduced by 60%. Customers feel understood and valued. Support agents focus on solving problems, not gathering information.
π Key Lessons
- Memory dramatically improves user experience
- Context-aware agents are more effective
- Personalization requires persistent memory
- Memory must be secure and privacy-compliant
π Hands-on Task
Practice thinking like an agent! Pick a task (like "organize my study schedule") and break it down:
- What information do you need first?
- What steps would you take?
- What tools would help?
- How would you know if you're done?
Extended Exercise: Design Reasoning Process
Design the reasoning process for a complex task:
- Task Selection: Choose a complex problem (e.g., "Plan a cross-country move")
- Break Down: List all sub-problems
- Reasoning Steps: For each sub-problem, define reasoning steps
- Decision Points: Identify where choices need to be made
- Memory Needs: What should be remembered?
- Error Handling: What if reasoning fails?
Reasoning Design Tip
Start with the end goal and work backwards. Ask "What do I need to know to achieve this?"
β Checklist
Understand these concepts:
π€ Mini Quiz
What is 'chain of thought' reasoning?
π¨ Common Pitfalls & Solutions
Pitfall 1: Shallow Reasoning
Problem: Agent jumps to conclusions without thinking through steps.
Solution: Encourage step-by-step reasoning in prompts.
# β Bad: No reasoning guidance
task = Task(description='Solve this problem')
# β
Good: Explicit reasoning steps
task = Task(
description='''
Solve this problem step by step:
1. Understand what's being asked
2. Identify what information you need
3. Gather that information
4. Analyze and process it
5. Formulate your answer
'''
)
Pitfall 2: Memory Overload
Problem: Agent tries to remember too much, gets confused.
Solution: Prioritize what to remember. Use memory selectively.
Memory Management
Not everything needs to be remembered. Focus on information that improves future interactions.
Pitfall 3: No Learning from Mistakes
Problem: Agent repeats the same errors.
Solution: Enable memory and learn from failures.
# β
Good: Agent learns from experience
agent = Agent(
role='Assistant',
goal='Help users',
memory=True, # Remember past interactions
verbose=True
)
# Agent will remember:
# - What worked before
# - What didn't work
# - User preferences
# - Common patterns
Pitfall 4: Reasoning Without Acting
Problem: Agent thinks but never takes action.
Solution: Ensure reasoning leads to concrete actions.
# β
Good: Reasoning leads to action
task = Task(
description='''
Think about this problem, then:
1. Reason through the solution
2. Take action based on your reasoning
3. Verify the result
''',
agent=agent
)
π‘ Best Practices
- Encourage Step-by-Step Thinking: Break problems into smaller parts
- Use Memory Strategically: Remember what improves future interactions
- Combine Reasoning with Action: Don't just think, act on conclusions
- Learn from Experience: Use memory to avoid repeating mistakes
- Be Transparent: Show reasoning process when helpful
- Set Reasoning Limits: Prevent infinite thinking loops
- Verify Reasoning: Check if conclusions make sense
π Reasoning Patterns
Pattern 1: Sequential Reasoning
Step-by-step, one after another:
Step 1 β Step 2 β Step 3 β Result
Pattern 2: Parallel Reasoning
Multiple paths explored simultaneously:
ββ Path A ββ
Start βββΌβ Path B ββΌββ Compare β Result
ββ Path C ββ
Pattern 3: Iterative Reasoning
Refine through multiple passes:
Pass 1 β Refine β Pass 2 β Refine β Final Result
Pattern 4: Hierarchical Reasoning
Break into sub-problems:
Main Problem
βββ Sub-problem 1
β βββ Step 1.1
β βββ Step 1.2
βββ Sub-problem 2
βββ Step 2.1
βββ Step 2.2
π Additional Resources
Chain of Thought Reasoning
Paper introducing chain-of-thought prompting for LLMs
ReAct: Reason + Act
Paper on combining reasoning and acting to improve agent performance
Memory Systems in AI Agents
Guide on implementing memory modules in agentic systems
π Challenge for GitHub
Create a flowchart showing how an AI agent thinks through a problem. Include:
- Problem identification
- Information gathering
- Reasoning steps
- Decision points
- Action taking
- Result evaluation
- Error handling
- Memory updates
Advanced Challenge: Build an agent that demonstrates:
- Chain-of-thought reasoning
- Memory usage (short-term and long-term)
- Learning from experience
- Transparent reasoning process
Share your flowchart and code on GitHub!
π Next Steps
Continue your learning journey:
- Next Module: Building with CrewAI - Apply reasoning in multi-agent systems
- Or Explore: Tools & Function Calling - Learn how agents use tools
- Deep Dive: Memory & State Management - Advanced memory techniques
Great Progress!
You now understand how agents think and reason. This foundation will help you build smarter, more effective agents!