Codex is the coding agent I use most often. It can inspect a repository, edit files, run the software, use other tools, and stay with a task long enough to finish it.
Why I use it
Generating code is the least interesting part. I care about the whole change: understanding the existing system, preserving unrelated work, running the result, and leaving something another person can review.
I use Codex for implementation, diagnosis, research, and the glue work around them. It is especially good when a task crosses boundaries between code, the browser, local apps, documentation, and Git. I can stay in one conversation while the agent works through the details.
I get better results when I give it a goal and treat it like a collaborator rather than an autocomplete box.