You may have seen people say they "built an app by talking to an AI". Behind that is usually an AI coding agent. Here is what one is, how it differs from the autocomplete in your editor, and why you still need to understand code.
Direct answer
An AI coding agent is a tool that takes a goal in plain language, plans the work, edits your files, runs commands such as tests, reads the output and tries again until it thinks the job is done. A coding assistant only suggests code and leaves the doing to you. With an agent, your job moves from typing code to briefing, reviewing and testing.
Assistant vs agent
| Coding assistant | Coding agent | |
|---|---|---|
| What it does | Suggests the next line or answers a question | Plans, edits several files, runs commands |
| Who acts | You paste or accept each suggestion | The agent acts, you review afterwards |
| Typical use | Autocomplete, explaining code | "Add a login page and make the tests pass" |
| Main risk | A wrong suggestion you accept | A wrong change spread across many files |
Most products now offer both: a chat and autocomplete side, and an agent mode.
Examples of AI coding agents
- Claude Code, from Anthropic, works in your terminal and in some editors. See Claude Code for beginners.
- Cursor is a code editor with an agent mode built in. See Cursor for beginners.
- GitHub Copilot started as autocomplete and now has an agent mode and a coding agent that works on GitHub tasks.
- OpenAI Codex is OpenAI's coding agent.
Products change quickly, so check each one's own site for what it does today. For a side by side, read Claude Code vs Cursor.
How an agent works
- You give a brief: the goal, examples, limits and what "done" means.
- It plans: which files to read and change.
- It edits and runs: writes code, runs tests or the program, reads errors.
- It loops until the checks pass or it gives up.
- You review the changes before anything ships.
Where agents go wrong
These are the mistakes you will see again and again:
- Misreading a vague brief. It confidently builds the wrong thing.
- Doing too much. It rewrites files you did not ask it to touch.
- Inventing things. Functions, settings or packages that do not exist.
- Marking its own homework. It writes weak tests that pass, so a green tick proves little.
- Mishandling secrets and data. Keys pasted into code, or private data shared with a tool.
None of these is rare. All of them are easier to catch if you can read the code.
So do you still need to learn to code?
Yes, at least the basics. You do not need to type every line any more, but you do need to read a change, tell whether it does what you asked, and know when a test proves something. Start with a beginner language such as Python: see is Python good for beginners.
Where Teyro fits
Teyro's Working with AI Coding Agents course teaches the working habits: write briefs an agent cannot misread, work in small steps, read every change, use tests as the judge and ship through review. You practise with a built-in agent in your browser that makes the mistakes real agents make, so you learn to catch them. It is made for people who can read a little Python, nothing to install, and free to start.
The bottom line
A coding agent does the typing, but you stay responsible for what ships. Learn to brief it well and check what it hands back.
