The Codex backend (client_version 0.156.0) served seven list+supported models on 2026-09-22: gpt-6-astra, gpt-6-sol, gpt-6-luna, then gpt-5.6-sol/terra/luna and gpt-5.5. Sol and Luna carry context 272000, efforts low..max, default medium. POST /codex/responses with kigi's codex headers answers 200 and completes for both.