variants: switching model back skips variant selection and resumes prior variant #36345

Summary

After selecting a model and a variant, switching to another model and back does not re-prompt for variant selection and silently resumes with the previously chosen variant. The variant can only be changed afterward via Ctrl+T.

Environment

• opencode version: 1.17.18
• OS: Darwin 25.5.0 (darwin arm64)
• Terminal: TERM_PROGRAM=ghostty, TERM=xterm-256color, COLORTERM=truecolor
• Shell: /bin/zsh
• Install/channel: Unavailable: not determined
• Active plugins: None found

Reproduction

1. Select a model and choose a variant (e.g. DeepSeek / high).
2. Switch to a different model.
3. Switch back to the original model.
4. Observe that no variant-selection screen appears and the prior variant is used automatically.
5. Press Ctrl+T to confirm the variant can still be cycled.

Expected Behavior

Switching back to a previously used model should either re-prompt for variant selection or otherwise make the active variant visible/selectable, consistent with the initial selection flow.

Actual Behavior

The model resumes with the previously selected variant with no variant-selection UI, requiring manual Ctrl+T cycling to change it.

Additional Context

Workaround: use Ctrl+T (variant_cycle) to change variants after switching back.