The models available to someone depend on the product surface and how they signed in. A model setting in your ChatGPT workspace doesn't automatically apply to Codex in the ChatGPT desktop app, Codex CLI, the IDE extension, Codex cloud, or the OpenAI API.
For the complete administration model, see Roles and workspace permissions.
Identify the model boundary
Check the current source for the surface the user is actually using. Don't copy a model catalog or assume that a ChatGPT model-picker setting has the same effect for Codex in the ChatGPT desktop app, Codex CLI, IDE extension, Codex cloud, and the API Platform.
Set a clear starting experience for employees
Review Models settings for your workspace before inviting a pilot group. Workspace owners and admins can configure separate starting defaults for Chat and for Work and Codex. Where supported, choose a starting model, reasoning level, speed, and new-chat behavior for Chat, Work, and local Codex surfaces.
Treat these choices as defaults, not permissions. Available models still depend on the member's seat, role, workspace or API identity, enforced workspace requirements, and the specific surface they're using. Starting defaults don't grant access to unavailable models or override those requirements. Codex cloud doesn't support changing its default model.
Fast mode availability depends on the workspace, product surface, and any
enforced features.fast_mode setting in
requirements.toml.
This setting can pin Fast mode on or off for managed local Codex clients; it
isn't a starting default and can't override workspace or product availability.
GPT-6 Astra in Enterprise
During the initial rollout, your organization must have Daybreak access before an administrator can enable Astra. Astra is off by default for ChatGPT Enterprise for the first two weeks after launch. Administrators in eligible workspaces can enable Astra for users or groups across Chat, Work, and Codex. Existing product eligibility still applies. Review your workspace model settings and confirm availability on each client used by your pilot group.
Enabling access and choosing a starting model are separate decisions. Check the applicable seat, role, and billing arrangement before setting Astra as a default. See pricing for allowance and billing guidance and safety monitoring for tasks that pause for review.
For API-key sign-in, Astra access follows the API organization and project associated with the key. Enabling Astra in a ChatGPT workspace doesn't grant API access. Early access with an API key also requires client configuration; ask your OpenAI account team for setup instructions. Selecting a model or changing local configuration doesn't grant access by itself.
Prepare for the GPT-5.4 retirement
On August 31, 2026, GPT-5.4 and GPT-5.4 mini retire from Codex for users signed in with ChatGPT. Update affected workspace defaults, saved model settings, managed configurations, custom agents, and scheduled tasks before then:
- Replace
gpt-5.4withgpt-5.6-terra(GPT-5.6 Terra). - Replace
gpt-5.4-miniwithgpt-5.6-luna(GPT-5.6 Luna).
The OpenAI API and Codex authenticated with your own API key aren't affected. See Codex models and managed configuration for migration details.
Separate access from runtime permissions
Model access determines whether a model is available to the authenticated user on a supported surface. Local permission profiles and managed requirements determine what an agent can do after a local run starts, such as which files it can change or which network destinations it can reach.
A permission profile can't grant model access. Model access also can't weaken the sandbox, approval policy, network controls, or source-system permissions that apply to a run.
Troubleshoot model access
If a user can't select an expected model:
- Confirm the product surface and sign-in method.
- Confirm the ChatGPT workspace or Platform API organization and project.
- Review the current access controls for that authentication boundary.
- Check whether the selected local client or Codex cloud supports the model.
Current sources
- ChatGPT Enterprise and Edu models and limits
- Manage workspace settings
- Role-based access control
- Codex models
- Codex feature availability by plan
- Authentication