unofficial integration

claudex — Claude Code on GPT-5.6

Claude Code stays your harness; GPT-5.6 becomes the model, through a localhost-only CLIProxyAPI sidecar signed in with your own ChatGPT/Codex subscription. One guided setup, an isolated session home, and your normal claude stays untouched.

1Watch it work

real machine · real release (ovm 0.1.0) · unedited commands · 57s

What you're seeing: the real installer, ovm claudex doctor's health checks, then ccxy launching Claude Code against the proxy — and the model answering, in its own words, "I'm GPT-5.6 Sol, running in Anthropic's Claude Code CLI harness."

2Set it up

curl -fsSL https://ovm.sh/install | sh
ovm claudex setup     # guided: proxy, sign-in, isolated home
ccxy                  # Claude Code, GPT-5.6 Sol, yolo

Setup checks before it does anything: it installs Claude Code if missing, stages a checksummed sidecar, connects your Codex account via browser OAuth, and seeds an isolated Claude home under ~/.ovm/claudex/ — your existing history, settings, and login are never mixed. Launch variants: claudex / ccx, ccxy (yolo), ccxf (fast tier), ccxyf.

3The honest part

This recipe was shared publicly by OpenAI's Codex lead. It is an unofficial integration — no endorsement by Anthropic or OpenAI is claimed or implied, and you use it at your own risk under your own accounts' terms. The sidecar binds to localhost only, with a key generated per machine; requests leave through your ChatGPT/Codex subscription, never a shared service.

Both sides of the thread, in public:

Tibo Sottiaux @thsottiaux · OpenAI Codex

If you aren't yet bold enough to install the Codex app, you can stay in the presence of your orange crab and point it at GPT 5.6 Sol. Takes 5 minutes. Kudos to Theo for explaining one of the ways to get this done. Step 1: Install CLIProxyAPI Step 2: Connect Step 3: Define

12 Jul 2026 view on X ↗

Boris Cherny @bcherny · Anthropic

@thsottiaux We are hiring if you would like to work at Anthropic! We don’t ban people for using harnesses with other models. Almost certainly it was a different account classifier that triggered. Looking into it, thanks for escalating.

8 Aug 2026 view on X ↗

Coverage note: claudex sessions are install-verified through the same registry gate as everything else OVM manages — the sidecar version you get has been installed and probed on real hardware before it is offered. See supported products for what the tiers mean.