Introduction

Over the past year, AI coding models have evolved from simple assistants into real development partners.

Two models currently getting the most attention in technical communities are:

• GPT-5.3 Codex — strong in structured coding workflows and tool-driven development
• Claude Opus 4.6 — strong in long-context reasoning and architecture-level thinking

Introduction

Over the last few years, AI coding tools have moved from “autocomplete assistants” to something much closer to real development partners. GPT-5.3 Codex is part of that shift.

Instead of just helping with small code snippets, Codex is now widely used for:

• Full feature implementation
• API scaffolding
• DevOps scripting
• Automation workflow generation
• Large project refactoring support