You’re Using Codex Wrong: Build with Specs, Context, and Guardrails

Most beginners use Codex the same way: they jump straight from prompt to code, hoping for great results.

That usually works just well enough to feel impressive and just badly enough to create rework, confusion, and risky changes.

In this workshop led by Codex Ambassador, Glaucia Lemos, we show you how to use AI the right way to build reliable code.

Instead of treating Codex like a prompt-to-code shortcut, you’ll learn a practical engineering workflow for using it in a more structured, safer, and more professional way. You’ll see how to prepare Codex before implementation by giving it the right context, surrounding it with the right guardrails, and then using a lightweight spec-driven development cycle to move from idea to reviewed, validated code.

The goal is not just to show you what Codex can do.
It is to help you work with Codex in a way that actually holds up in real software development.

If you want to move from AI-curious to confidently productive with Codex, this workshop is for you. If you're evaluating Claude, the same principles you learn in this workshop can be applied using Claude.

By the end of the workshop, you’ll be able to:

• Explain why prompt-to-code is often not enough for reliable AI-assisted development

• Give Codex better context before asking it to implement anything
• Define useful constraints, conventions, acceptance criteria, and boundaries
• Build a lightweight harness around Codex using tests, checklists, review loops, and validation steps
• Turn a small requirement into a clear, actionable spec
• Break a spec into implementation tasks Codex can help execute
• Use Codex to implement a small feature more effectively
• Review diffs, reason through tests, debug issues, and improve changes
• Decide when a change is safe enough to accept and ship

You’ll leave with a workflow that helps you use Codex more safely, with more confidence and less wasted effort.

You should walk away with:

• A practical introduction to OpenAI Codex as an AI coding agent
• A clear mental model for how Codex fits into the software development workflow
• Beginner-friendly guidance on using Codex for:
• • code explanation
  • feature implementation
  • debugging
  • testing
  • code review
• Hands-on demos that show how to move from understanding a codebase to making useful changes
• Practical prompting techniques using goals, context, constraints, and acceptance criteria
• A framework for reviewing AI-generated changes before accepting or shipping them
• Basic safety and quality practices for working with AI coding agents
• Live Q&A and next steps for continuing after the session

You’ll also receive:

✔ workflow templates and reusable systems

✔ practical implementation patterns

✔ full workshop recording

✔ certificate of completion

This workshop is ideal for:

This workshop is ideal for:

• Developers who are curious about Codex but want a more practical starting point
• Beginners who want more than a surface-level feature walkthrough
• Engineers who want to use AI coding agents in a safer, more structured way
• Developers who want to learn how to move from idea to validated code change with less risk
• Teams evaluating whether Codex can fit into real development workflows

No advanced AI experience is required. Basic programming familiarity is recommended.

Prerequisites

To get the most from the workshop, participants should have:

• Basic familiarity with programming concepts
• A ChatGPT account with Codex access
• Optionally, VS Code or the Codex CLI installed for follow-along exercises

No prior experience with AI coding tools is required.