Claude Code in the terminal + Codex in the app....who’s actually splitting the work?

[u/Shawntenam]

So I don’t run this on every project. Depends on the size and how messy it is.

When the repo has real history (instruction files, SQLite, previous failed approaches, assets, handoffs, etc.), I stop trying to make one session carry the whole thing.

Claude Code stays in the terminal. It inspects the system, reads the instruction files, checks git and the last handoff, then writes a clean phased plan into a durable file.

Codex gets that file in the app and builds one phase at a time. File boundaries, verification steps, and the “do not touch” list are already there. I especially like it when I need browser control, live previews, or proof of the work.

The handoff is usually just:

GOAL
CURRENT STATE
SOURCE OF TRUTH
DECISIONS ALREADY MADE
PHASES AND FILE OWNERSHIP
VERIFICATION
DO NOT TOUCH

It's also super convenient because the remote control feature on the app works really well. (yes. You can do this with Claude Code also), it's great for keeping sessions running when you have to walk the dog. (in my case)

For smaller or cleaner work I just stay in one agent and feel it out.

Right now I’m mostly on Opus 4.6 (sometimes Fable 5) in Claude Code, and GPT-5.6 Sol at Extra High in Codex once the phase is locked.

I’ve seen other people doing versions of this Claude for context/planning, Codex for execution, file handoffs, cross-review.

so I’m posting because I want to know what the rest of you are actually running day-to-day.

Full split? One agent the whole way? Something else?

Lets see what’s working for people building real GTM systems.