Codex 0.156: Luna Fallback, /tui, and Better Worktrees
This episode covers the latest Codex terminal release, including the new rate-limit fallback to GPT-6 Luna, the model picker split between Luna and Sol, and the upgraded fullscreen /tui experience with better search, copying, and tmux/SSH paste handling.
We also dig into /usage analytics, default worktrees for subagents, preserved streamed output on failures, /daemon updates, native Mermaid and math rendering, voice mode defaults, and several important security fixes.
Chapter 1
Codex 0.156.1 Catalog Expansion, Fullscreen TUI, and Usage Analytics
Maya
So you are in the middle of a heavy coding session, hit a rate limit, and instead of kicking you out or breaking your prompt, Codex now just... hands you GPT 6 Luna?
Ethan Park
Exactly. With the zero point one five six point one hotfix that dropped right after version zero point one five six point zero, the rate limit switch prompt automatically suggests GPT 6 Luna. And hey, before we dive into the rest of this massive terminal release, a quick shoutout to Jellypod for helping us bring you these fast daily updates.
Maya
Yeah, Jellypod is great. But wait, GPT 6 Luna versus Sol in the actual model catalog picker? We do not have to edit hidden config files anymore?
Ethan Park
No more string hacks. You can just open the picker and choose GPT 6 Sol when you need deep reasoning for architecting, or GPT 6 Luna for those fast, low latency turns.
Maya
That is so much cleaner. But honestly, the thing that got me when I tested this yesterday was typing slash t u i.
Ethan Park
Oh, the fullscreen terminal interface?
Maya
Yes! It turns your terminal into a full terminal screen experience. You get real transcript search, mouse selection, and right click copying. I, uh, I was refactoring four files at once, searching through a long stream, and copy pasting code snippets.
Ethan Park
And it did not break your indentation? Because usually when you copy out of a tmux or SSH session, the tabs turn into a complete mess.
Maya
It preserved the exact tab indentation! They specifically fixed clipboard forwarding and individual keystroke paste handling for tmux and SSH. It was, um, surprisingly seamless.
Ethan Park
That is a huge relief for terminal purists. And while you are in there, you can also run slash usage now.
Maya
Right, slash usage. That opens up a whole analytics dashboard, right?
Ethan Park
Yeah. It breaks down your overall account token totals, but more importantly, it tracks plugin and skill token consumption per turn. So if an active background plugin is eating up half your context window before you even send a prompt, you can see it instantly.
Maya
That is so good. No more mystery context window bloat.
Chapter 2
Background Daemon Isolation, Worktree Defaults, and Sandbox Security Fixes
Ethan Park
Now, under the hood, there are some pretty major changes in how Codex manages background processes and git checkouts.
Maya
Like worktrees being turned on by default?
Ethan Park
Right. Worktree support is enabled by default now. When subagents spawn off to work on side tasks, they get isolated git worktrees automatically so they do not collide with your active branch.
Maya
And what happens if one of those subagents crashes midway through generating a plan?
Ethan Park
They fixed that too. Streamed answers and plans are preserved even if a turn fails, gets interrupted, or receives subagent completion events. You do not lose what was already written.
Maya
That is huge. What about managing the actual background server? I saw something about slash daemon.
Ethan Park
Yeah, you can update the local background server using slash daemon, or if you are running in a containerized build pipeline like Docker or CI, you can pass no daemon to bypass it entirely.
Maya
Why would someone want no daemon in CI?
Ethan Park
Well, I, uh, I actually ran into this last week on a containerized setup. If a background server stays alive after the build job finishes, it can leave orphaned background processes locking your local state databases or hanging the runner container. Passing no daemon keeps everything strictly ephemeral.
Maya
Ah, that makes total sense for infrastructure. Oh, and speaking of visual output, it now renders Mermaid diagrams natively in terminal responses!
Ethan Park
Yep, Mermaid diagrams and display equations directly in the output. Plus, voice conversations are enabled by default now, with an F eight toggle and a slash voice settings picker.
Maya
Though they did officially scrub the old friendly and pragmatic personality settings from the documentation and configuration. They do not select response styles anymore.
Ethan Park
Yeah, deprecated for good. And just a heads up on security isolation fixes, they closed gaps around non loopback inbound connections in Windows sandboxes, and fixed read only file handle write permissions on macOS.
Maya
Good to know. So whether you are jumping into slash t u i or running headless with no daemon, this zero point one five six release is packed.
Ethan Park
Packed indeed. Alright, that is it for today, talk to you next time.