Autonomous Agents

Autonomous agents are AI systems that can independently decompose goals, plan actions, execute tools, and self-correct without constant human guidance. The challenge isn't making them capable - it's making them reliable. Every extra decision multiplies failure probability.

This skill covers agent loops (ReAct, Plan-Execute), goal decomposition, reflection patterns, and production reliability. Key insight: compounding error rates kill autonomous agents. A 95% success rate per step drops to 60% by step 10. Build for reliability first, autonomy second.

2025 lesson: The winners are constrained, domain-specific agents with clear boundaries, not "autonomous everything." Treat AI outputs as proposals, not truth.

Principles

• Reliability over autonomy - every step compounds error probability
• Constrain scope - domain-specific beats general-purpose
• Treat outputs as proposals, not truth
• Build guardrails before expanding capabilities
• Human-in-the-loop for critical decisions is non-negotiable
• Log everything - every action must be auditable
• Fail safely with rollback, not silently with corruption

Capabilities

• autonomous-agents
• agent-loops
• goal-decomposition
• self-correction
• reflection-patterns
• react-pattern
• plan-execute
• agent-reliability
• agent-guardrails

Scope

• multi-agent-systems → multi-agent-orchestration
• tool-building → agent-tool-builder
• memory-systems → agent-memory-systems
• workflow-orchestration → workflow-automation

Tooling

Frameworks

• LangGraph - When: Production agents with state management Note: 1.0 released Oct 2025, checkpointing, human-in-loop
• AutoGPT - When: Research/experimentation, open-ended exploration Note: Needs external guardrails for production
• CrewAI - When: Role-based agent teams Note: Good for specialized agent collaboration
• Claude Agent SDK - When: Anthropic ecosystem agents Note: Computer use, tool execution

Patterns

• ReAct - When: Reasoning + Acting in alternating steps Note: Foundation for most modern agents
• Plan-Execute - When: Separate planning from execution Note: Better for complex multi-step tasks
• Reflection - When: Self-evaluation and correction Note: Evaluator-optimizer loop

Patterns

ReAct Agent Loop

Alternating reasoning and action steps

When to use: Interactive problem-solving, tool use, exploration

REACT PATTERN:

""" The ReAct loop:

1. Thought: Reason about what to do next
2. Action: Choose and execute a tool
3. Observation: Receive result
4. Repeat until goal achieved

Key: Explicit reasoning traces make debugging possible """

Basic ReAct Implementation

""" from langchain.agents import create_react_agent from langchain_openai import ChatOpenAI

Define the ReAct prompt template

react_prompt = ''' Answer the question using the following format:

Question: the input question Thought: reason about what to do Action: tool_name Action Input: input to the tool Observation: result of the action ... (repeat Thought/Action/Observation as needed) Thought: I now know the final answer Final Answer: the answer '''

Create the agent

agent = create_react_agent( llm=ChatOpenAI(model="gpt-4o"), tools=tools, prompt=react_prompt, )

Execute with step limit

result = agent.invoke( {"input": query}, config={"max_iterations": 10} # Prevent runaway loops ) """

LangGraph ReAct (Production)

""" from langgraph.prebuilt import create_react_agent from langgraph.checkpoint.postgres import PostgresSaver

Production checkpointer

checkpointer = PostgresSaver.from_conn_string( os.environ["POSTGRES_URL"] )

agent = create_react_agent( model=llm, tools=tools, checkpointer=checkpointer, # Durable state )

Invoke with thread for state persistence

config = {"configurable": {"thread_id": "user-123"}} result = agent.invoke({"messages": [query]}, config) """

Plan-Execute Pattern

Separate planning phase from execution

When to use: Complex multi-step tasks, when full plan visibility matters

PLAN-EXECUTE PATTERN:

""" Two-phase approach:

1. Planning: Decompose goal into subtasks
2. Execution: Execute subtasks, potentially re-plan

Advantages:

• Full visibility into plan before execution
• Can validate/modify plan with human
• Cleaner separation of concerns

Disadvantages:

• Less adaptive to mid-task discoveries
• Plan may become stale """

LangGraph Plan-Execute

""" from langgraph.prebuilt import create_plan_and_execute_agent

Planner creates the task list

planner_prompt = ''' For the given objective, create a step-by-step plan. Each step should be atomic and actionable. Format: numbered list of steps. '''

Executor handles individual steps

executor_prompt = ''' You are executing step {step_number} of the plan. Previous results: {previous_results} Current step: {current_step} Execute this step using available tools. '''

agent = create_plan_and_execute_agent( planner=planner_llm, executor=executor_llm, tools=tools,