One friend says Codex is great. Another says they use Claude Code every day. You search around and run into GPT, Claude, and a string of version numbers. You haven’t even learned all the names yet, and your webpage is already running behind schedule.
Let’s start by sorting these business cards into the right piles. You can get to know them without crowning a champion first.
Meet Codex
Codex is OpenAI’s Agent product. When it works with code and files, it can read and edit files, run commands, and check the results. You describe what you want, and it uses tools to move the task forward.
It comes in several forms, such as a command-line tool, an editor extension, and an app. Each one looks different, and which features you get depends on the specific product and environment. OpenAI’s official Harness write-up explains how the different ways into Codex relate to the execution software underneath.
In this tutorial, “choosing Codex” means choosing this Agent as your entry point. The model is a separate setting, which we’ll get to next. Some model names include the word Codex, too, so when you see a full name, notice whether it’s showing up as a product entry point or in a model list.
Meet Claude Code
Claude Code is Anthropic’s Agent product. It can work with project files, write code, and run related checks based on requests in plain language. The “Code” in the name tells you it grew up around programming, but you don’t have to know how to code to use it.
You can ask it to make an invitation page, or have it explain some existing files first. What it can actually do still depends on the tools and permissions the current entry point provides. For the different entry points and what each can do, the official Claude Code docs have the final word.
The easiest mix-up here is Claude vs. Claude Code. The first can mean the Claude family of models, or the chat product. The second is the name of an Agent product. When someone says “I’m using Claude,” you often need a peek at their screen to know which one they mean.
One table to put each name in its place
When you start a new chat on Agent.Space, besides Codex and Claude Code, you’ll also see Grok Build, OpenCode, DeepSeek Harness, and Lite, the lightest option with the fewest tools. The little tags on the cards are short hints from the product, not a ranking. Once you can tell “product entry points” from “models,” new names get much easier to place.
So which one first?
For this simple invitation page, Codex (selected by default) works fine. You can also switch to an Agent you know better. You choose the model below the input box, and the list only shows models that work with that Agent. Make sure you have enough usage for it, then start with the same clear, small task.
There’s no need to give products fixed personalities, like one that “only writes code” and another that’s “born with better taste.” What you get also depends on your request, the model, the context, and the tools. A more direct test: Does the page open? Is all the info there? When you ask for a change, does it hit the mark?
Also, don’t assume a subscription to one product automatically lets you use another. To see which models and how much usage you have on Agent.Space, check what its own screens say.
What changes with a different entry point
If you install an Agent on your own computer, the files and related programs usually live in your local environment. With Agent.Space, project work happens in a cloud Workspace by default, and you talk to it through your browser.
If your Mac already has Claude Code or Codex installed, you can also connect that computer through the Agent.Space Mac App. When you start a new chat, those Agents show up with a “This Mac” tag. They use your own subscription over there and don’t spend Agent.Space credits. The next chapter has more on the different computers you can pick from.
That’s also why our next stop is the “Cloud computer.” Once you’ve picked an Agent that can do the work, you still need to know where it works, and where the finished work ends up.
For a more detailed comparison, read how Codex and Claude Code differ in practice. For now, let’s get the place ready where the invitation page will be built.