Agentic Engineering: Building AI Systems That Act
Playbook
Agentic AIMulti-Agent SystemsSystem Design

Agentic Engineering: Building AI Systems That Act

From chatbots to autonomous agents—the patterns, architectures, and practices for building AI that reasons, plans, and executes.

Published Jan 02, 202610 min read

[!NOTE] Promise Theory = Autonomy & Trust
Highly effective human teams don't work by "Master/Slave" commands; they work by Promises.

  • Philosophical: This aligns with Autonomy and Social Contract Theory.
  • Engineering: By adopting Promise Theory (Mark Burgess), we build agents that commit to outcomes rather than just executing scripts, making the system resilient to partial failures.

The world is moving fast beyond simple chatbots. We are entering the era of Agentic AI Engineering Systems—autonomous, reasoning actors that don't just "talk" about work, but "execute" it within the complex topology of your enterprise. The evolution from chatbots to agents represents a fundamental shift in how we build AI systems. A chatbot responds. An agent acts. It breaks down complex tasks, uses tools, maintains state, and iterates toward goals—all with minimal human intervention.


What Makes an Agent

An agent is more than an LLM with a prompt. It's a system with four core capabilities:

Capability Description Example
Reasoning Analyze problems and plan approaches "This task requires three steps: first I'll search, then analyze, then summarize"
Tool Use Execute actions via APIs and functions Call a web search, run code, query a database
Memory Retain context across interactions Remember user preferences, track conversation history
Autonomy Make decisions without constant supervision Choose which tool to use, when to ask for help, when to stop

"The best agents don't just process—they strategize, act, and adapt."


Core Agent Architectures

Architecture 1: ReAct (Reasoning + Acting)

The foundational pattern. The agent alternates between reasoning and acting.

graph LR
    A(Think) --> B(Act)
    B --> C(Observe)
    C --> D{Done?}
    D -->|No| A
    D -->|Yes| E(Output)

When to use: Single-agent tasks requiring tool use and reasoning. Best for well-defined, sequential workflows.


Architecture 2: Plan-and-Execute

Separate planning from execution. A planner creates a step-by-step plan, then an executor follows it.

graph LR
    A(Input) --> B(Plan)
    B --> C(Do 1)
    C --> D(Do 2)
    D --> E(Do 3)
    E --> F{OK?}
    F -->|No| B
    F -->|Yes| G(Done)

When to use: Complex, multi-step tasks where upfront planning improves reliability.


Architecture 3: Multi-Agent Systems

Orchestrate multiple specialized agents that collaborate to solve complex problems.

graph LR
    A(Lead) --> B(Research)
    A --> C(Analyze)
    A --> D(Write)
    B --> E(Data)
    C --> F(Insight)
    D --> G(Report)
    E --> C
    F --> D
Pattern Structure Best For
Hierarchical Orchestrator delegates to specialized agents Complex workflows with clear subtasks
Peer-to-Peer Agents communicate directly Collaborative reasoning, debates
Pipeline Output of one agent feeds into next Sequential processing stages

Tool Design Principles

Agents are only as good as their tools. Well-designed tools make agents more reliable.

Category Examples Considerations
Information Retrieval Web search, database queries, RAG Rate limits, caching, result quality
Code Execution Python interpreter, SQL runner Sandboxing, timeouts, resource limits
External APIs Weather, payments, messaging Authentication, error handling
State Management Memory updates, task tracking Consistency, concurrency

Best practices for tool design:

  • Clear, typed parameters with sensible defaults
  • Comprehensive error messages for debugging
  • Rate limiting and retry logic built-in
  • Timeout handling to prevent hangs

Memory Architectures

Agents need memory to maintain context and learn from interactions.

Memory Type Use Case Implementation
Buffer Memory Last N messages Simple array, FIFO eviction
Summary Memory Compressed conversation history LLM summarizes older turns
Vector Memory Semantic retrieval of past context Embed and search conversation history
Entity Memory Track key entities mentioned Extract and maintain entity state

Agent Evaluation

How do you know if your agent is actually working?

Metric What It Measures Target*
Task Completion Rate % of tasks successfully finished >80%+
Tool Success Rate % of tool calls that succeed >90%+
Steps to Completion Efficiency of agent reasoning Minimize
User Intervention Rate How often humans need to help <20%
Latency (P95) Time to complete tasks <45s

[!NOTE] *Targets are illustrative design goals for production systems. Actual performance varies significantly by domain complexity and model choice.


Common Anti-Patterns

Anti-Pattern Problem Solution
God Agent Single agent tries to do everything Specialize agents by capability
Runaway Loops Agent gets stuck in infinite reasoning Add step limits, break conditions
Blind Tool Calling Using tools without checking results Validate outputs, handle errors
Context Amnesia Forgetting important info mid-task Explicit state management
Over-Planning Spending too much time planning Balance planning with action
No Guardrails Agent can take harmful actions Define clear boundaries

Production Considerations

Observability

Track thought traces, tool calls with latency, errors, and decision rationale.

Cost Management

  • Model tiering: Fast/cheap for simple steps, powerful for complex reasoning
  • Caching: Cache tool results and common queries
  • Early termination: Stop when task is complete, don't over-reason

Safety & Guardrails

  • Action limits per task (max API calls, max cost)
  • Human-in-the-loop for high-stakes actions
  • Content filters for sensitive data

Choreography vs. Orchestration

  • Choreography: Reactive, decoupled coordination where agents react to events in a decentralized "dance."
  • Orchestration: Centralized control flow where a lead agent or workflow engine explicitly directs the graph progress.

[!TIP] Theoretical Foundation: Promise Theory
For truly autonomous multi-agent systems, skip centralized orchestration and look to Mark Burgess's Promise Theory. It provides a formal framework for how independent agents can collaborate through voluntary "promises" rather than imposed commands, leading to much more resilient distributed systems.

The Agent Maturity Ledger

Autonomy isn't a toggle; it's an evolutionary path. We track this progression through the Maturity Ledger, where each stage provides the structural data and human precedents required to safely reach the next.

graph LR
    V1[**V1**<br/>Intent Routing] --> V2[**V2**<br/>Cognitive Copilot]
    V2 --> V3[**V3**<br/>Autonomous Agent]
Version Objective Learning Outcome Evolutionary Feed
V1: Routing Can the system classify and route intents reliably? High-noise areas; department silos; semantic ambiguity. Cleaned intent data; deterministic routing maps.
V2: Copilot Can the system retrieve context and propose reasoned acts? Human override patterns; SOP friction; retrieval gaps. Curated knowledge sets; reasoning "precedents."
V3: Autonomous Can the system execute scoped tasks without human intervention? Trust breakdown thresholds; escalation boundaries. Refined fallback logic; expansion criteria.

[!IMPORTANT] Respect the V1 Foundation. The "boring" intent classification in V1 is what creates the grounded scoping required for V3 to act without hallucinating context.


Getting Started

Phase Focus Deliverables
Week 1-2 Single agent + 2-3 tools Working ReAct agent for one use case
Week 3-4 Memory + evaluation Persistent context, basic metrics
Month 2 Multi-agent or complex workflows Orchestration, specialized agents
Month 3 Production hardening Observability, guardrails, scaling

The Bottom Line

Agentic AI is where LLMs become truly useful for complex, real-world tasks. But agents are systems, not prompts—they require thoughtful architecture, robust tooling, and careful evaluation.

Start simple: one agent, a few well-designed tools, clear success criteria. Then iterate based on what breaks.


References & Further Reading



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