Anatomy of a CLI-Based Code Assistant

Most writing on CLI-based coding assistants reads like an industry architecture piece, five layers, token percentages, a vendor comparison table, all of it built to sound authoritative rather than to be true. The real reason I use a CLI-based agent has nothing to do with architecture, it's that I was already living in the terminal before any of these tools existed.

the terminal was already home

I've always been a vim and terminal person, that part predates AI entirely. Editing files in vim comes naturally to me, and the plain black screen is genuinely soothing to look at after a long day, that's not a productivity argument, it's just true. The terminal is also where I log into remote servers, check log files, and hunt for patterns across them, none of that lives inside an IDE. A CLI-based coding agent didn't ask me to change anything about how I already worked, it just showed up where I already was.

coding is half the job, and the CLI covers the other half too

An IDE plugin only helps with the coding half of my workflow, and coding is maybe half of it. The rest is exactly what I just described, remote servers, logs, pattern-finding, all terminal-native tasks an editor extension has no reach into. Switching between terminal tabs to cover all of it is simpler than switching between an IDE and a separate terminal window for the tasks the IDE can't touch. That's the actual case for a CLI-based agent, not that it's a superior architecture, but that it's the one tool that follows me across the whole job, not just half of it.

the honest comparison, only two tools deep

I've used Codex and Claude, and ruled out Cursor immediately because it's IDE-based, which defeats the premise for me before it even gets a fair trial. Between the two I've actually used, Claude wins on quality of output, a larger context window, and the ability to actually work through complex, multi-step problems without losing the thread. Codex didn't hold up as well on any of those when I used it. That's not a market map, it's just what's true from where I sit, two tools tried, one that stuck.

conclusion

I don't think the terminal is winning because of some architectural inevitability, I think it's winning for people like me because it never asked us to leave. The tools got smarter. The place I was already working stayed the same. That's the whole story, not five layers, not a token budget, just a preference that turned out to scale.