#Noob question

1 messages · Page 1 of 1 (latest)

glacial thistle
#

Can you tell me how codex and agent mode works and kindly give a guide on how a new user get hands on feel of uses and capabilities of codex and agent mode?

fiery perchBOT
#

Hi @glacial thistle. I'm kapa.ai, your friendly support bot. I will try to answer your question by searching through the knowledge base. :wave:

#

Here’s a concise, beginner-friendly overview based only on the docs you shared.

1. What is Codex?

Codex is OpenAI’s AI coding agent. It helps you:

  • Write, review, and ship code faster
  • Navigate your repo, edit files, run commands, and execute tests
  • Work either locally (CLI / IDE) or in the cloud [What is Codex?; Code generation]

You can use it:

2. How Codex works (high level)

  • You give Codex a prompt or spec (e.g., “Add pagination to this API”).
  • It reads your repo, edits files, runs tests/commands, and proposes changes.
  • In cloud mode, it runs tasks in an isolated sandbox with your repo and environment, and you review/merge the results. [What is Codex?; Code modernization]

Codex is powered by Codex-tuned models like gpt-5.1-codex-max and gpt-5.2-codex, which are optimized for coding tasks. [Code generation; Codex Prompting Guide]

3. How to get access to Codex

From the docs:

#

Steps:

  1. Make sure you have an active ChatGPT subscription (or Free/Go while it’s included).
  2. If needed, upgrade in your ChatGPT account settings. [Getting started with Codex]

4. First hands-on with Codex (noob-friendly path)

Option A – Easiest: Codex Web

  1. Go to **https://chatgpt.com/codex**. [Code generation; Getting started with Codex]
  2. Sign in with your ChatGPT account (and connect GitHub if prompted). [Getting started with Codex]
  3. Start with simple tasks, for example:
    • “Read this repo and explain the architecture.”
    • “Add unit tests for this file.”
    • “Refactor this function to be more readable.”

Codex will run tasks in the cloud and show you the changes it proposes.

Option B – Codex CLI / IDE (local pairing)

From the docs, you can:

#

High-level flow (details are in the linked docs, not fully shown here):

  1. Install the CLI or IDE extension from the Codex docs. [Code generation]
  2. Sign in with ChatGPT when prompted. [Getting started with Codex]
  3. Open a small repo and try:
    • “Explain this file.”
    • “Implement feature X in this module.”
    • “Write tests for this function.”

For more advanced workflows (multi-agent, MCP, etc.), the Agents SDK examples show how Codex can be wired into agent systems, but that’s beyond a pure beginner intro. [Building workflows with Codex; Experimental Codex tool]

5. What is Agent mode (in ChatGPT / Atlas)?

Agent mode is a feature in ChatGPT’s browser experience (Atlas) that lets ChatGPT take actions in the browser for you, not just chat. [Agent mode]

It can:

#
  • Navigate pages, click, and complete multi-step flows in your current tab
  • Use sites you’re already signed in to (in “logged-in” mode)
  • Use browser memories (if enabled) to remember sites you’ve visited [Agent mode]

Agent mode is available on Pro, Plus, Business, Enterprise, and Edu plans in supported countries. [ChatGPT Agent getting started]

6. How Agent mode works (high level)

  • You describe a task (e.g., “Find the cheapest flight on this site for next weekend”).
  • The agent acts in your current browser tab: clicking, filling forms, navigating.
  • It pauses for clarification or confirmation when needed and can be interrupted at any time. [ChatGPT Agent getting started; Agent mode]

Safety constraints from the docs:

  • It cannot run code in the browser, download files, or install extensions.
  • It cannot access other apps on your computer or your file system.
  • It pauses on sensitive sites (e.g., financial institutions) to ensure you’re watching. [Agent mode]

You can also use a logged-out mode, where it doesn’t use existing cookies or logged-in sessions unless you explicitly approve. [Agent mode]

7. First hands-on with Agent mode (noob-friendly path)

Step 1 – Open the Ask ChatGPT sidebar

#
  1. In the Atlas browser, click Ask ChatGPT at the top right.
  2. A side panel opens with:

Step 2 – Turn on Agent mode

You can:

  • In the side panel, choose Agent mode from the + menu, or
  • In a new tab, click + in the prompt window and select Agent mode. [Agent mode]

Step 3 – Try simple tasks

Examples you can try:

  • “Log in to this site and navigate to my order history.”
  • “Fill out this form with the following info: …”
  • “Compare prices for this product across these tabs and summarize.”

The agent will act in the current tab and report progress in the side panel. [Agent mode]

Step 4 – (Optional) Set custom instructions

You can guide how Agent mode behaves:

  1. Click your profile icon → Settings.
  2. Choose Agent mode.
  3. Add instructions (e.g., preferred sources, approval checkpoints, required steps). [Agent mode]

8. How Codex and Agent mode differ (in simple terms)

#
  • Codex: Focused on code. Works in your dev environment (CLI/IDE/web) to read, modify, and run code, and help with code review and modernization. [What is Codex?; Code generation]
  • Agent mode: Focused on web actions. Works in your browser to click, navigate, and complete workflows on websites. [Agent mode]

They’re complementary: Codex helps you build and maintain software; Agent mode helps you operate on the web.

If you tell me your setup (e.g., “I have ChatGPT Plus and VS Code” or “I’m just using the browser”), I can narrow this down to a very short, step-by-step “do this first, then this” starter path using only what’s in these docs.

Note: you can ask me a follow up question by @ mentioning me again :speech_balloon:

#

@glacial thistle Kapa.ai is still learning and improving, please let me know how I did by reacting below.

glacial thistle
#

@fiery perch I use chat gpt plus on my android s25 ultra and my windows 11 laptop. Kindly let me know a step by step guide on getting a first time feel just to get an example of its working and usages on both platforms.

fiery perchBOT
#

Let me check the knowledge base for you again. One moment! :books:

#

Below is a “first‑time hands‑on” guide for you, based only on the docs you shared. I’ll cover:

  • Codex (coding agent) on your Windows laptop
  • Agent mode (web actions) where it’s documented (Atlas / ChatGPT web)

The docs don’t describe Codex or Agent mode specifically inside the Android app UI, so I’ll flag those gaps where relevant.

1. Using Codex with your ChatGPT Plus account

You already have ChatGPT Plus, which includes Codex. [Using Codex with ChatGPT]

For a first feel, the simplest path from the docs is:

Step 1 – Confirm access

Codex is included with:

You already have Plus, so you’re covered.

Step 2 – Pick a Codex interface

From the docs, you can use Codex via: [Getting started with Codex; What is Codex?]

  • Codex web: <https://chatgpt.com/codex> (requires GitHub connection)
  • Codex CLI (terminal on Windows)
  • Codex IDE extension (VS Code / Cursor / other VS Code forks)
  • Codex app (Mac only – not relevant for your Windows laptop)

For a first test on Windows, the docs most clearly describe:

  • Codex web
  • CLI / IDE (if you’re comfortable installing tools)

Step 3 – First hands-on with Codex Web (easiest)

#

  1. On your Windows 11 laptop, open a browser and go to:
    <https://chatgpt.com/codex> [Code generation; Getting started with Codex]

  2. Sign in with your ChatGPT Plus account.

  3. If prompted, connect your GitHub account (required for Codex web). [Getting started with Codex]

  4. Start a simple task, for example:

    • “Read this repo and explain the architecture.”
    • “Add unit tests for this file.”
    • “Refactor this function to be more readable.”

    Codex will run the task in the cloud, in an isolated sandbox with your repo and environment, and propose code changes you can review and use. [What is Codex?]

This gives you a clear feel for Codex as a cloud coding agent.

Step 4 – (Optional) Try Codex in your local tools

If you want to see Codex working directly with files on your Windows laptop:

#
  1. Choose a client from the docs: [Getting started with Codex]
    • Codex CLI
    • Codex IDE extension (VS Code / Cursor)
  2. Install it following the instructions linked from the Codex docs (CLI / IDE pages). [Code generation]
  3. When you run the CLI or open the IDE extension, sign in with ChatGPT (no API key needed). [Getting started with Codex]
  4. Open a small project and try prompts like:
    • “Explain this file.”
    • “Implement feature X in this module.”
    • “Write tests for this function.”

Behind the scenes, Codex navigates your repo, edits files, runs commands, and executes tests as needed. [What is Codex?]

Android note: The docs don’t describe a Codex client inside the Android ChatGPT app itself; they only mention Codex on web, CLI, IDE, and iOS app. [Updates to Codex]
So for now, your best Codex experience is on the laptop via web/CLI/IDE.

2. Getting a feel for Agent mode (ChatGPT Agent / Atlas)

There are two related “agent” concepts in the docs:

  1. ChatGPT agent mode (general feature in ChatGPT)
  2. Agent mode in Atlas browser (ChatGPT-built-in browser)

2.1 ChatGPT Agent mode (general)

From the docs:

#
  • Agent mode lets ChatGPT complete complex online tasks on your behalf, switching between reasoning and action. [ChatGPT agent release notes]
  • It can research across public websites, uploaded files, and connected third‑party sources, and perform actions like filling forms and editing spreadsheets. [ChatGPT agent release notes]
  • It’s available on Pro, Plus, Business, Enterprise, Edu plans, and works on Web, mobile (iOS/Android), and desktop apps (Mac/Windows). [ChatGPT Agent FAQ; ChatGPT Agent getting started]

So with ChatGPT Plus on:

  • Your Android S25 Ultra (ChatGPT mobile app)
  • Your Windows 11 laptop (ChatGPT web or Windows app)

…you should be able to use agent mode, but the docs don’t show the exact Android UI steps. They do show the generic way to start it:

Step 1 – Start Agent mode (generic)

On supported ChatGPT surfaces (web / mobile / desktop):

  1. Open a chat.
  2. From the tools menu, select Agent mode, or type /agent in the composer. [ChatGPT Agent getting started]
  3. Describe the task you want completed (e.g., “Research the best 3 budget phones under $400 and summarize pros/cons”).
  4. The agent will begin executing, pausing for clarification or confirmation when needed. [ChatGPT Agent getting started]

This is the core “feel”: you give a high‑level task, and it autonomously browses/acts, while checking in with you.

#

Limitation: The docs don’t detail the exact Android button labels or screens, only that agent is supported on mobile. [ChatGPT Agent FAQ]

2.2 Agent mode in Atlas (browser with ChatGPT built in)

Atlas is a separate browser (macOS only per the docs), but it’s where agent mode is described in the most concrete, step‑by‑step way. [ChatGPT Atlas release notes]

Even though you’re on Windows/Android, this description is useful to understand how agent mode behaves.

How Atlas Agent mode works

Examples of what it can do:

  • Research a topic across multiple pages
  • Fill out forms
  • Navigate logged‑in sites (if you allow it)

Safety boundaries in Atlas agent mode: [ChatGPT Atlas release notes; Agent mode in Atlas]

#
  • Cannot run code in the browser, download files, or install extensions
  • Cannot access other apps or your file system
  • Pages visited in agent mode are not added to browsing history
  • You can run it in logged‑out mode so it doesn’t use existing cookies or log into accounts without explicit approval

You can also set custom instructions for agent mode (preferred sources, approval checkpoints, etc.) via Settings → Agent mode. [Agent mode in Atlas]

Platform note: Atlas is documented as macOS‑only; there’s no mention of a Windows or Android version in the sources you provided. [ChatGPT Atlas release notes]

3. Concrete “first task” ideas for you

Given what the docs explicitly cover, here’s how you can get a feel on each device:

On your Windows 11 laptop

For Codex (coding):

  1. Go to <https://chatgpt.com/codex> and sign in. [Code generation]
  2. Connect GitHub if asked. [Getting started with Codex]
  3. Start a task like:
    • “Analyze this repo and summarize the main components.”
    • “Add unit tests for the user service in this project.”

For Agent mode (general ChatGPT agent):

  1. Open ChatGPT in your browser (or Windows app).
  2. In a new chat, select Agent mode from the tools menu or type /agent. [ChatGPT Agent getting started]
  3. Try a task like:
    • “Research the top 5 Windows 11 productivity apps, compare features and pricing, and give me a recommendation.”
#

The agent will handle the research and ask you for confirmations when needed.

On your Android S25 Ultra

The docs say:

  • Agent mode is supported on mobile (iOS/Android) for paid plans. [ChatGPT Agent FAQ]
  • But they don’t show the exact Android UI steps.

So, based on the docs:

  1. Open the ChatGPT Android app and start a new chat.
  2. Look for a tools menu or similar option where you can select Agent mode, or try typing /agent in the message box. [ChatGPT Agent getting started]
  3. Give it a task like:
    • “Plan a 3‑day trip to Tokyo with a budget of $X, including hotel and food suggestions.”

You should see it perform multi‑step reasoning and online actions (within the constraints described in the agent docs), but the exact Android UI is not detailed in the sources.

If you tell me whether you’re more interested in coding help or web task automation first, I can narrow this down further into a very short “Day 1: do exactly these 3 things” checklist, still only using what’s in the docs.

Note: you can ask me a follow up question by @ mentioning me again :speech_balloon:

#

@glacial thistle Kapa.ai is still learning and improving, please let me know how I did by reacting below.

pliant moth
#

@fiery perch you mentioned agent mode can access browser and do things for you right? does it consume more quota or is it separated? and how can i see the quota if it's separated

fiery perchBOT
#

Let me check the knowledge base for you again. One moment! :books:

#

Agent mode does have its own usage limits, and they are separate from normal chat messages, but they still sit under your overall ChatGPT plan.

From the docs:

  • Agent mode has monthly message limits by plan:
    • Plus: 40 messages/month
    • Pro: 400 messages/month
    • Business & Enterprise: 40 messages/month
    • Business & Enterprise on flexible pricing: 30 credits/message [Agent usage limits]
  • Only the initial user‑initiated agent request counts toward this limit. Follow‑up clarifications or auth steps during the same agent run do not count. [Agent usage limits]

So yes: using agent mode does consume a separate “agent messages” quota in addition to your normal ChatGPT usage.

Can you see how much of that quota you’ve used?

The knowledge sources you provided do not describe any UI or dashboard to see remaining agent‑mode messages. They only state the monthly limits and how counting works; there’s no mention of a counter or usage view for agent mode specifically. [Agent usage limits]

So, based on these docs:

  • Agent mode usage is separately limited (e.g., 40 agent messages/month on Plus).
  • The docs do not explain how to check your remaining agent quota; they only say you’ll be subject to those limits and “reasonable rate limits.” [Agent usage limits]
#

If you need an exact remaining count, the safest option is to contact OpenAI Support from the Help Center, since it’s not documented as a self‑serve metric in these sources.

Note: you can ask me a follow up question by @ mentioning me again :speech_balloon: