Course Roadmap: What We'll Build & Learn
Learn what OpenAI's Codex is and master its core superpowers: working with local files, persistent memory, external plugins, custom skills, computer & browser automation, and recurring scheduled tasks.
What You Need Before Starting:
- Codex desktop app installed on your Mac or Windows PC
- No coding experience required — just a curiosity to learn AI agent workflows
- A local folder on your computer with a few sample files or documents to practice with
What is Codex? The AI Agent Super App Explained
Why Codex represents a massive leap forward from standard web chatbots.
At first glance, Codex might look similar to ChatGPT or Claude because you can open a chat window and type prompts. But under the hood, they are completely different technologies.
When you chat with a standard web AI, everything is locked inside a cloud browser window. When you upload a file, it lives on remote servers, and the AI cannot touch your actual computer, desktop apps, or local hard drive.
Codex is OpenAI's AI Agent Super App designed to perform real knowledge work and coding tasks directly on your computer. It has full filesystem access to read and write local files, controls your desktop interface (mouse, keyboard, apps), tests web pages inside a real browser, and runs background automated jobs on a schedule.
Traditional Methods vs. Codex
File Storage & Access
Execution & Desktop Control
Memory & Custom SOPs
The 6 Core Superpowers We Will Master
Native Local Filesystem
Read, edit, batch-process, and create real files (Excel, Word, HTML, Code) right on your machine.
Dual Persistent Memory
Teach the agent your exact formatting rules and style preferences in `agents.md` once, and it remembers forever.
Connected Tool Plugins (@)
Connect to Email, Notion, GitHub, and Databases with two clicks and query them in natural language.
Reusable Skills & SOPs (/)
Package your best workflows into repeatable slash-command playbooks that run in seconds.
Computer & Browser Use
Let the agent control your mouse and keyboard to manipulate desktop apps or test live web UI.
Scheduled Automations
Put recurring tasks on autopilot so your agent wakes up and runs your workflows on a schedule.
Quick Cheat Sheet: Essential Commands
Keep these core syntax triggers handy as you follow the walkthrough modules below:
| Command / Trigger | What It Does |
|---|---|
@<filename> | Tag a local project file to bring its full content into the prompt context |
@<plugin-name> | Attach an external tool connection (Email, Notion, Database, GitHub) |
/<skill-name> | Trigger a saved, repeatable procedural SOP recipe |
@computer-use | Let the agent control your mouse and keyboard to manipulate desktop apps |
@browser-use | Launch automated in-browser navigation and click-through UI testing |
Turn this into a skill | Convert the current chat's verified output into a permanent reusable skill |
Getting Started: Local File Access & Setting Up Your Workspace
Understand how Codex interacts with your local drive, how to organize project folders, and how to multitask with parallel agents.
If you've used standard AI chat apps on the web, you're used to uploading files into a cloud window. Codex is fundamentally different: it is an AI agent that lives on your computer. It can read folders from your Downloads directory, create real Excel sheets or code files in your Documents, and organize everything directly on your hard drive.
1Step 1: Create a Dedicated Project Workspace
$ Create a new project folder in ~/Documents/my-workspace2Step 2: Tell the Agent to Process Local Files
$ Look at the files in my ~/Downloads/raw-reports folder. Analyze the contents, categorize each entry, and create a structured analytical Excel spreadsheet with summary charts.3Step 3: Reference Existing Documents Using '@'
$ Please review @analysis.xlsx and turn the key takeaways into an interactive landing page outline for my team.Do:Organize your work into Project Folders
Keep each goal (e.g., 'Quarterly Research', 'Website Redesign', 'Financial Audit') in its own project folder. This keeps all generated documents cleanly sorted in Finder or File Explorer.
Avoid:Creating loose standalone chats in the root directory
Avoid starting chats outside of a project folder, as it makes it harder to track where the agent created your documents.
Do:Run multiple agent chats in parallel
You don't have to wait for one task to finish! You can open 2 or 3 chats in the same project simultaneously. One agent can process data while another drafts copy or builds code.
Pro Tip for Beginners
Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Memory Mastery: Teaching the Agent How You Like Things Done
Learn how to use manual memory (agents.md) so the agent permanently remembers your preferences, formatting styles, and quality standards.
Have you ever found yourself repeating the same instructions to an AI over and over? ('Make it concise', 'Use bullet points', 'Include a sidebar'). Codex solves this with Persistent Memory. There are two types of memory you need to know about: Manual Memory (which you control) and Automatic Memory (which the agent manages in the background).
This living file lives in your project or global root. Codex reads it on every single prompt to tailor its output to your preferences.
# My Personal Guidelines & Style Preferences ## Document & Layout Rules - Layout: When creating learning docs, always include a left navigation sidebar with a table of contents. - Formatting: Use clear comparison boxes (Do vs. Avoid) and numbered step-by-step walkthroughs. - Tone: Instructional, encouraging, and easy for beginners to follow. Avoid jargon without explaining it. - Code Standards: Write clean, well-commented code with zero placeholders.
Do:Tell the agent to remember styles you love
When the agent produces a great output, simply say: 'I love this layout. Please remember to always use this format in agents.md whenever I ask for similar documents'.
Avoid:Manually editing the background 'memories/' folder
Codex maintains an internal telemetry memory folder for its own observations. Let the agent manage that automatically—only edit `agents.md` yourself.
Pro Tip for Beginners
Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Connecting Your Tools: Supercharging Codex with Plugins (@)
Connect external tools like Email, Notion, GitHub, and Databases so your agent can pull live context and take real actions.
An AI agent is only as helpful as the tools it can access. With Codex Plugins, you can connect your agent to the software you already use in two clicks. Typing '@' in your prompt brings up a menu of connected tools that the agent can read from and write to.
1Step 1: Enable Plugins in the Plugins Tab
$ Open Plugins tab -> Connect 'Email' and 'Notion'2Step 2: Ask the Agent to Research and Synthesize Across Tools
$ Look at my recent incoming messages from the past week using @email. Find all actionable requests, cross-reference them with our project notes in @notion, and build a summary table.Do:Use '@' to see available tools
Just type '@' in the prompt box anytime to see the quick menu of all installed plugins and active project documents.
Avoid:Sending emails or modifying databases without review
Ask the agent to draft changes or summaries first so you can review the output before confirming external actions.
Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Skills & SOPs: Turning Good Outputs into Reusable Playbooks (/)
Master the 'Iterative Workflow Distillation' technique to turn successful tasks into permanent slash-command recipes (/skill).
What if you could package a multi-step task that took you 30 minutes into a single command that runs in 30 seconds? That is what Skills are. A skill is a standardized recipe (stored as a `SKILL.md` instruction file) that teaches your agent exact steps to execute a recurring workflow.
1Step 1: Do the Task and Iterate Until You Love the Result
$ Analyze these raw data logs, build an executive dashboard with color-coded risk levels, and include a 3-step action checklist.2Step 2: The Magic Prompt: Reverse-Engineer into a Skill
$ I love this output! Please turn this entire process into a reusable skill called data-audit-report so I can run it anytime.3Step 3: Run Your New Skill with a Slash Command
$ /data-audit-report analyze the latest batch in ~/Downloads/new-batchThe agent generates clean, reusable instruction playbooks for you automatically.
--- name: data-audit-report description: Scans data logs, categorizes risk levels with color formatting, and outputs an action plan. --- # Operational Steps 1. Ingest target CSV/JSON files from specified folder. 2. Validate data fields and calculate summary metrics. 3. Generate formatted dashboard with High/Medium/Low indicators. 4. Output a 3-step recommended action plan.
Do:Build skills via 'Workflow Distillation'
The easiest and most reliable way to create a skill is to do the task manually first, get the exact output you want, and then tell the agent: 'Turn this into a skill'.
Avoid:Writing abstract skill instructions from scratch
Avoid guessing instructions in advance. Let the agent extract instructions from real, verified work.
Do:Improve skills every time you get a great result
If a skill run produces an exceptionally neat diagram or layout, tell the agent: 'Update the skill so it always formats charts this way'.
Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Visual Assets & Diagrams: Generating Media Right on Canvas
Learn how to generate technical diagrams, flowcharts, and custom imagery directly inside your project without leaving Codex.
Great technical and business work requires visual clarity. Codex includes built-in multimodal generation and diagramming capabilities. You can ask for system architecture diagrams, process flowcharts, or visual illustrations, and the agent saves them directly as image files in your project folder.
1Step 1: Generate Visual Flowcharts & Diagrams
$ Please create a visual flowchart diagram showing our 3-step user onboarding process. Save it as a clean image in my project folder.2Step 2: Generate Custom Imagery for Presentations or Web Pages
$ Generate 3 clean, professional product mockup illustrations with modern lighting and a dark background for our landing page.Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Hands-Off Automation: Computer Use & In-Browser UI Testing
See how the agent controls your mouse, keyboard, and browser to test apps and automate repetitive desktop tasks.
One of Codex's most groundbreaking capabilities is Computer Use and Browser Use. When you enable `@computer-use` or `@browser-use`, the agent can literally see your screen, move the mouse cursor, click buttons, type text, and test web pages just like a human operator.
1Step 1: Automated Desktop Software Control (@computer-use)
$ Open my presentation software, create a new 5-slide presentation, and place our generated charts on each slide using @computer-use.2Step 2: Automated In-Browser Testing & QA (@browser-use)
$ Build a responsive quiz app in index.html, then open the browser and test that every button, navigation link, and quiz answer works correctly using @browser-use.Common Beginner Pitfall & How to Fix It
What happens: The agent clicks the wrong area on desktop apps
How to solve it: Keep the target application window clearly visible on your screen and specify exact button names in your prompt.
Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Putting Tasks on Autopilot: Scheduled Background Automations
Learn how to turn verified skills into hands-free recurring background jobs that run every hour, day, or week.
Once you have built a skill you love (Module 4), you don't even have to remember to run it manually! With Automations, you can tell Codex to run that exact skill on a schedule in the background, updating your spreadsheets or summaries automatically.
1Step 1: Schedule Your Reusable Skill
$ Please run our /data-audit-report skill every Friday at 9:00 AM automatically and update the summary spreadsheet.2Step 2: Manage & Inspect Your Automations
$ Navigate to the Automations tab in CodexDo:Test skills manually before scheduling them
Always run a skill 2 or 3 times in chat to make sure it produces flawless results before putting it on a recurring schedule.
Avoid:Scheduling uncontrolled write operations
For important workflows, configure the automation to write reports to a review folder so you can verify changes when you start your day.
Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Bonus Superpower: Ambient Screen Context (Zero-Upload Assistance)
Learn how ambient visual context allows your agent to understand what's on your screen in real time without taking manual screenshots.
Have you ever wanted to ask an AI a question about what you're currently looking at without having to take a screenshot and upload it? With Ambient Visual Context enabled in settings, Codex observes your active workspace in real time and can answer questions or generate companion documents instantly.
Pro Tip for Beginners
Hands-On Practice Checklist
Try each of these steps on your computer and check them off as you complete them:
Crash Course Starter Files & Templates
Codex Beginner-to-Pro Starter Pack
Includes copyable `agents.md` memory templates, standard `SKILL.md` recipes, and recommended plugin configuration blueprints.