Building AI Agents from Scratch (Part 1): Core Architecture and Underlying Principles Explained

Dev.to / 6/12/2026

💬 OpinionDeveloper Stack & InfrastructureIdeas & Deep AnalysisTools & Practical Usage

Key Points

  • The article defines an AI agent as a system that perceives its environment, reasons and plans autonomously, and uses external tools to take actions toward a specific goal.
  • It contrasts autonomous agents with traditional chatbots by highlighting that chatbots typically rely on single-pass, reactive dialogue, while agents iteratively run an “agent loop” and can recover from failures.
  • The piece explains a commonly used architecture formula: Agent = LLM + Memory + Planning + Tool Use, where the LLM provides reasoning, memory stores context, planning breaks down goals, and tool use performs real-world actions.
  • It illustrates why agent-style execution matters for multi-step, dependent tasks (e.g., searching flights, checking loyalty points, and booking), which are difficult for standard chatbots to handle reliably.

Continue reading this article on the original site.

Read original →