Gemini discovery works but a model request fails

Symptom. df-gemini models lists a model, but generation or Live fails.

Cause. Discovery access does not establish generation quota, model availability, billing, or region access. A 429 can mean an exhausted or zero project quota; a 503 indicates temporary service unavailability. Google-account Pro status does not establish paid Developer API access.

Confirm. Check the same project’s AI Studio rate-limit page and bash ~/dotfiles/install/auth.sh google-status. The probe returns failure and a safe error class/status without exposing its key or WebSocket URL.

Fix. For a 503, retry with backoff. For quota/billing failures, select a model with available quota or deliberately configure paid billing. Do not create extra API keys expecting more quota: project keys share the same pool. See the Google API guide.