Codex subscription
Route your ChatGPT plan through BitRouter via the Codex backend — OAuth, no OpenAI API key.
Have a ChatGPT Plus or Pro plan? Use it as a model source through the Codex backend. bitrouter login openai-codex runs the same OAuth flow OpenAI's Codex CLI uses, stores the refreshing token, and attaches it to requests on the openai-codex provider — so your ChatGPT subscription covers the tokens, with no OPENAI_API_KEY.
openai-codex is not openai. This is a separate provider. It reaches ChatGPT's Codex backend (chatgpt.com/backend-api/codex), speaks the Responses API only, and is authenticated solely by your subscription's OAuth — it does not share endpoints or credentials with the standard openai (API-key) provider. For pay-per-token access to the public OpenAI API, use the openai provider with a key instead.
Log in
bitrouter login openai-codexThis opens OpenAI's authorize page in your browser (PKCE, on a pinned loopback port), and on approval stores the credential under $XDG_DATA_HOME/bitrouter/oauth-tokens.json. The token auto-refreshes — log in once. To remove it:
bitrouter logout openai-codexAlready signed in to Codex? The login menu offers "Import an existing session from the vendor CLI" — BitRouter adopts the credential the Codex CLI already stored (macOS Keychain or $CODEX_HOME/auth.json), with no fresh browser sign-in. The imported token refreshes like any other.
Multiple accounts
Credentials are keyed by (provider, label). Use --label to keep more than one account:
bitrouter login openai-codex --label workRoute to it
No bitrouter.yaml block is required — openai-codex is built in, and the stored credential is found at request time. Address a model your plan exposes by its registry id:
bitrouter route openai-codex:gpt-5-codexThen start BitRouter and send a request. Use the provider-qualified id openai-codex:<model> to pin the request to your subscription; see Models for the exact ids the Codex backend serves.
Learn more
- Codex — point the Codex CLI at BitRouter (a harness), distinct from using your plan as a model source here.
- Model fallback — fail over from your subscription to another source on overload.
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