OpenAI Confirms GPT-5.5 Survives Only via API Key After Codex Retirement

OpenAI confirmed GPT-5.5 will retire from ChatGPT, ChatGPT Work, and default Codex on October 14. The model does not disappear entirely: it stays reachable through the API Platform, and inside Codex sessions specifically authenticated with an API key rather than a ChatGPT login. Teams that have not set up API-key authentication for Codex will lose default access to GPT-5.5 on that date and need to migrate to GPT-5.6 Sol or GPT-6 Astra instead. The distinction is a practical one for anyone running Codex in CI or in an internal tool: workflows wired to a ChatGPT session token break on October 14, while workflows already using an API key keep working with no code change beyond confirming the key stays valid. OpenAI's announcement gives about a month of lead time, which is short for teams that have not audited how their Codex integrations authenticate. The safest move is to check now, since API-key auth is the one path OpenAI is explicitly keeping open.