| name | codex-windows-gpt-5-6-dropdown-fix |
| description | Repair missing GPT-5.6 Sol, Terra, and Luna entries in the Windows Codex Desktop model picker when an API-key or third-party provider can already serve those models. Use for the verified Windows MSIX build in references/compatibility.json, before any task that modifies or reinstalls Codex Desktop. |
Windows GPT-5.6 Dropdown Fix
Use this workflow only when the provider can already complete a small CLI request
with the target model, but Codex Desktop does not show it in the picker.
Preconditions
- Confirm Windows, Codex Desktop, and the installed package version.
- Read
references/compatibility.json. Stop if the installed version is absent.
- Confirm the provider supports every model that will be added to the catalog.
- Back up local Codex state before changing
config.toml or replacing the package.
- Run package-changing work from external PowerShell, VS Code, or another agent
environment. Do not reinstall the Codex Desktop process hosting this task.
Workflow
- Run
scripts/build-patched-msix.ps1 -Mode Check and require a patchable or
already-patched result. Stop on every other result.
- Use
assets/model-catalog.26.707.example.json only when the backend list is
missing GPT-5.6. Copy it to the user's Codex home, trim unsupported models,
and set the top-level model_catalog_json path in user-level config.toml.
- Explain that the catalog is a full replacement and this compatibility rule
deliberately displays every catalog entry, including entries marked hidden.
- Run
scripts/build-patched-msix.ps1 -Mode Build -OutputRoot <large-local-path>.
Inspect the generated local package and metadata before installation.
- Obtain explicit confirmation before running
-Mode Install. Require an
elevated PowerShell session. Do not pass -AllowNonPreservingRemove unless a
backup exists and the user understands the application-data risk.
- Restart the exact OpenAI.Codex package, confirm the picker entries, and send a
small request through each intended model. Keep provider URLs and logs local.
Rollback
Remove the model_catalog_json override, restore the official Store package,
then remove the locally trusted signing certificate by the thumbprint recorded
in local build-metadata.json. Do not commit that metadata or the certificate.
Resources
scripts/patch-model-filter.ps1: exact-match, failure-closed asset patcher.
scripts/build-patched-msix.ps1: staged preflight, build, and installation.
references/compatibility.json: reviewed version-specific patch rules.
assets/model-catalog.26.707.example.json: conditional catalog template.