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Concepts

AI Agents

Autonomous systems that combine language models with reasoning, memory, and tool use to execute complex multi-step tasks with minimal human intervention.

growing#ai-agents#llm#autonomous-systems#tool-use#agentic-ai#react-pattern

What they are

An AI agent is a system that uses a language model as its reasoning core, but goes beyond answering questions: it can plan, execute actions, observe results, and adjust its behavior in a closed loop.

The fundamental difference between a chatbot and an agent is autonomy. A chatbot answers a question and waits for the next one. An agent receives a goal, decomposes the problem, decides which tools to use, executes intermediate steps, and delivers a result — all with minimal human intervention.

Components of an agent

A typical agent has four components:

  1. Language model (LLM): the brain that reasons, plans, and generates text. Decides what to do at each step.
  2. Memory: stores conversation context, previous results, and accumulated knowledge. Can be short-term (context window) or long-term (vector databases, files).
  3. Tools: external functions the agent can invoke — APIs, databases, file systems, browsers, terminals. The Model Context Protocol (MCP) standardizes how agents access these tools.
  4. Execution loop: the reasoning-action-observation cycle the agent repeats until the task is complete.

Execution patterns

ReAct (Reason + Act)

The most common pattern. The agent alternates between reasoning about what to do and executing actions:

Thought: I need to look up the current price of AAPL
Action: search_price(ticker="AAPL")
Observation: $187.50
Thought: Now I can respond to the user
Response: The current price of AAPL is $187.50

Plan and execute

The agent first creates a complete plan and then executes each step. Useful for complex tasks where order matters.

Multi-agent

Multiple specialized agents collaborate to solve a problem. Each agent has a specific role (researcher, writer, reviewer) and they communicate with each other.

Current frameworks

FrameworkLanguageFocus
LangGraphPythonState graphs for agentic flows
CrewAIPythonAgent teams with roles
Strands AgentsPythonModular agents from AWS
AutoGenPythonMulti-agent conversations
Vercel AI SDKTypeScriptAgents in web applications

Current limitations

  • Reliability: agents can enter loops, make incorrect decisions, or hallucinate about the state of the world.
  • Cost: each step in the loop consumes tokens. A complex task can require dozens of model calls.
  • Security: an agent with tool access can execute destructive actions if not properly constrained.
  • Observability: debugging why an agent made a specific decision is difficult. Traces and logs are essential.

Why it matters

Agents represent the next leap in AI applications: from systems that answer questions to systems that complete tasks. Understanding their execution patterns, limitations, and available frameworks is essential for building applications that go beyond chat.

References

  • LLM Powered Autonomous Agents — Lilian Weng (OpenAI), 2023. Foundational reference on agent architecture.
  • ReAct: Synergizing Reasoning and Acting in Language Models — Yao et al., 2022. The paper that formalized the ReAct pattern.
  • The Landscape of Emerging AI Agent Architectures — Masterman et al., 2024. Survey of agent architectures.
  • LangGraph Documentation — Reference framework for graph-based agents.

Related content

  • Artificial Intelligence

    Field of computer science dedicated to creating systems capable of performing tasks that normally require human intelligence, from reasoning and perception to language generation.

  • Model Context Protocol (MCP)

    Open protocol created by Anthropic that standardizes how AI applications connect with external tools, data, and services through a universal interface.

  • AWS Bedrock

    AWS serverless service providing access to foundation models from multiple providers (Anthropic, Meta, Mistral, Amazon) via unified API, without managing ML infrastructure.

  • Takeaways: Why 2026 Is the Year to Build a Second Brain

    Key takeaways from Nate B Jones' second brain series — from the original 8 building blocks to Open Brain (Postgres + MCP), the two-door principle, and the implementation gap.

  • Takeaways: The Renaissance Developer — Dr. Werner Vogels

    Key takeaways from Dr. Werner Vogels' final keynote at AWS re:Invent 2025, where he presents the Renaissance Developer framework and argues why AI will not replace developers who evolve.

  • Content Agent QA Review: PR #187

    Findings from manual review of PR

  • Takeaways: The Adolescence of Technology

    Key takeaways from Dario Amodei's essay on civilizational risks of powerful AI and how to confront them.

  • Building a Second Brain in Public

    Chronicle of building a second brain with a knowledge graph, bilingual pipeline, and agent endpoints — in days, not weeks, and what that teaches about the gap between theory and working systems.

  • MCP Dual Interface Demo

    Demonstration of dual-interface architecture where the same business logic serves both a traditional web application and an MCP server for AI tools.

  • Git Metrics MCP Server

    MCP server for analyzing git repository metrics and understanding team health. Published on npm as @jonmatum/git-metrics-mcp-server.

  • Content Agent with Strands and Bedrock

    Three-agent system that automates the bilingual MDX content lifecycle: deterministic QA auditing, surgical fixes, and full upgrades — all orchestrated with Strands Agents, Claude Sonnet 4 on Amazon Bedrock, and GitHub Actions with a diamond workflow pattern.

  • Tool Use Patterns

    Design strategies and patterns for AI agents to select, invoke, and combine external tools effectively to complete complex tasks.

  • Strands Agents

    Open source SDK from AWS for building AI agents with a model-driven approach. Functional agents in a few lines of code, with multi-model support, custom tools, MCP, multi-agent, and built-in observability.

  • Semantic Search

    Information retrieval technique that uses vector embeddings to find results by meaning, not just exact keyword matching.

  • Retrieval-Augmented Generation

    Architectural pattern that combines information retrieval from external sources with LLM text generation, reducing hallucinations and keeping knowledge current without retraining the model.

  • Prompt Engineering

    The discipline of designing effective instructions for language models, combining clarity, structure, and examples to obtain consistent, high-quality responses.

  • Multi-Agent Systems

    Architectures where multiple specialized AI agents collaborate, compete, or coordinate to solve complex problems that exceed a single agent's capability.

  • Function Calling

    LLM capability to generate structured calls to external functions based on natural language, enabling integration with APIs, databases, and real-world tools.

  • Chain-of-Thought

    Prompting technique that improves LLM reasoning by asking them to decompose complex problems into explicit intermediate steps before reaching a conclusion.

  • AI Safety

    Field dedicated to ensuring artificial intelligence systems behave safely, aligned with human values, and predictably, minimizing risks of harm.

  • AI Coding Assistants

    Tools using LLMs to help developers write, understand, debug, and refactor code, from autocomplete to agents that implement complete features.

  • Agentic Workflows

    Design patterns where AI agents execute complex multi-step tasks autonomously, combining reasoning, tool use, and iterative decision-making.

Concepts