you are giving it instructions but it's running a while loop with a list of tools and it can poke around in your code base until it thinks it's done whatever you ask for.

See Claude Code, windsurf, amp, Kilcode, roo, etc.

I might describe a change I need to have made and then it does it and then I might say "Now the tests are failing. Can you fix them?" and so on.

Sometimes it works very great. sometimes you find yourself arguing with the computer.