Twitter/X

You can run Grok 4.5 inside Codex without an xAI API key, metered billing, or…

2026-07-26 · 20:24 UTC ·@dr_cintas ·1 min read

Brief

opencodex is a tiny local proxy that translates Codex's Responses API into calls Grok 4.5 understands, letting you tunnel xAI's model through Codex without an xAI API key or metered billing. Using OAuth with an X Premium subscription as the credential, the author reports a ~3-minute install (bun, npm install -g @bitkyc08/opencodex, ocx login/init/start) and says Grok 4.5 has just improved.

Why it matters

You can run Grok 4.5 inside Codex without an xAI API key, metered billing, or pay-as-you-go; an X Premium subscription acts as the credential via OAuth to route Grok through Codex (author @dr_cintas, published 2026-07-26).

Key details

  • Setup (about 3 minutes) uses opencodex: install bun, npm install -g @bitkyc08/opencodex; ocx login xai (OAuth with your X account); ocx init; ocx start; then run: codex -m "xai/grok-4.5" "your prompt".
Source evidence

you can run Grok 4.5 inside Codex now - no xAI API key, no metered billing, no pay-as-you-go 🤯

if you have X Premium it’s a cheatcode: your subscription is your access.

the mechanism: opencodex is a tiny local proxy that translates Codex’s Responses API into whatever your model speaks. You OAuth into xAI with your X account and it routes Grok straight through Codex.

the subscription you already pay for becomes the credential.

how to set up (3 min):

  1. install bun, then: npm install -g @bitkyc08/opencodex
  2. ocx login xai - sign in with your X account, OAuth handles the rest
  3. ocx init to inject into Codex, then ocx start
  4. run it: codex -m “xai/grok-4.5” “your prompt”

that’s the full setup.

and the timing’s perfect: Grok 4.5 just got a lot better.

Video