Gateway: closed-weight frontier provider catalog with per-provider API key UI

[gregjkal]

Summary

Gateway should know about all closed-weight frontier models and offer a UI for adding an API key per provider. Start with GPT-6-Astra.

Details

From the #cppa-wg21-org design discussion on 2026-09-09:

• The Remote tab of the gateway config should present a tree: provider > model family > expandable versions. Vinnie's sketch:

  > Anthropic (rolldown)
    > Opus
    > Fable
    > Sonnet
  

  Each family opens to show individual versions.
• Model availability depends on the user's subscription (example: Fable is available on a team account but not a personal account), so the UI and the routing layer need a "model not available" failure mode.
• The PromptForge executor needs to know the model names so it can map tools.
• Open question: are closed models equal siblings to open-weight models, differing only on the detail page (API key instead of download links)? Current direction is simply two tabs, Local | Remote.

Related

• Updatable provider catalog file: Gateway: updatable provider/model catalog file #25
• Installer pre-populates gateway.env: Installer: create gateway.env pre-populated with empty provider key variables #26
• Umbrella config UI redesign: Config UI redesign: usability and appearance #28

Current code: crates/gateway-config-ui/ui/src/views/models-view.ts (Remote scope), crates/gateway-config/src/config.rs.