I've only used codex with the responses v1 API and there it's the complete opposite. Already generated reasoning tokens even persist when you send another message (without rolling back) after cancelling turns before they have finished the thought process

Also with responses v1 xhigh mode eats through the context window multiples faster than the other modes, which does check out with this.

I'm pretty sure that Codex uses reasoning.encrypted_content=true and store=false with the responses API.

reasoning.encrypted_content=true - The server will return all the reasoning tokens in an encrypted blob you can pass along in the next call. Only OpenaAI can decrypt them.

store=false - The server will not persist anything about the conversation on the server. Any subsequent calls must provide all context.

Combined the two above options turns the responses API into a stateless one. Without these options it will still persist reasoning tokens in a agentic loop, but it will be done statefully without the client passing the reasoning along each time.

It’s not the responsibility of the agent to write this transcript, it’s emacs, so I don’t have to worry about the agent forgetting to log something. It’s just writing the buffer to disk.

But tbh OpenAI openly supporting OpenCode is the bigger draw for me on the plan but do want to spend more time with native Codex as a base of comparison against OpenCode when using the same model.

I’m just happy to have so many competitive options, for now at least.

I also was annoyed by Theo saying that.

I work on SSL bio acoustic models as context.

I have a tool that reduces agent token consumption by 30%, and it's only viable because I can hook the harness and catch agents being stupid, then prompt them to be smarter on the fly. More at https://sibylline.dev/articles/2026-01-22-scribe-swebench-be...

However, it seems to really only be good at coding tasks. Anything even slightly out of the ordinary, like planning dialogue and plot lines it almost immediately starts producing garbage.

I did get it stuck in a loop the other day. I half-assed a git rebase and asked codex to fix it. It did eventually resolve all debased commits, but it just kept going. I don't really know what it was doing, I think it made up some directive after the rebase completed and it just kept chugging until I pulled the plug.

The only other tool I've tried is Aider, which I have found to be nearly worthless garbage

Generally I have noticed Gpt 5.2 codex is slower compared to Sonnet 4.5 in Claude Code.