How do Codex-related agentic coding capabilities typically go beyond simple code suggestions?

A suggestion engine produces text and stops. You are the one who applies it, runs it, and discovers it was wrong. An agentic tool closes that loop itself: it reads the files it needs, makes edits across as many of them as the change actually touches, runs the build or the test suite, reads what came back, and tries again. What it hands you has already been through a check.

That is why the useful unit becomes a task rather than a snippet. "Rename this concept everywhere and keep the tests passing" is not a paragraph of code — it is a dozen small edits plus a command whose output decides whether the work is finished. Describing that as a request is easy; doing it by pasting suggestions is not.

The trade is control, which is why these tools carry permission settings, approval prompts and a diff to review. Something that edits your files and runs your commands needs a boundary you set deliberately, and a result you read before it goes anywhere.