* studio/frontend: correct Think pill aria-label before model loads
`reasoningEnabled` defaults to true in the chat-runtime store, so on a
fresh /chat with no model the Think pill renders disabled + visually
off (LightbulbOffIcon, data-active="false"), but its aria-label still
reads "Disable thinking" -- screen readers announce it as if the
button is currently on. Add a `disabled` branch between
reasoningLockedOn and effectiveReasoningEnabled so the label reads
"Thinking (model not loaded)" while the button is unreachable, then
falls through to the normal enable/disable copy once a model is
loaded. Apply the same fix to the equivalent pill in shared-composer
(where the disabled flag is named `reasoningDisabled`).
* studio/frontend: Think pill distinguishes !modelLoaded vs unsupported reasoning
Address review feedback on #5655 (chatgpt-codex-connector + gemini-code-assist
both flagged the same edge case):
The previous `disabled` branch labeled the Think pill "Thinking (model not
loaded)" whenever the button was disabled, but `disabled` is defined as
`!(modelLoaded && effectiveSupportsReasoning)` (in thread.tsx) and
`!modelLoaded || !effectiveSupportsReasoning` (in shared-composer.tsx).
Both cover the second case where a model IS loaded but does not support
reasoning at all (e.g. Llama-3.2-1B-Instruct), which mislabeled the pill
for screen-reader users.
Split the branch so the no-model case keeps "Thinking (model not loaded)"
and the loaded-but-unsupported case reads "Thinking (not supported by this
model)". Locked-on / enabled / disabled labels are unchanged.
Verified by re-running the Playwright probe:
- no model -> aria-label "Thinking (model not loaded)"
- Llama-3.2-1B loaded -> aria-label "Thinking (not supported by this model)"
- reasoning-capable loaded, OFF -> "Enable thinking"
- reasoning-capable loaded, ON -> "Disable thinking"
- locked-on model -> "Thinking is required for this model"
* studio/frontend: extract Think pill aria-label helper, fix effort dropdown pre-load mislabel
Address review consensus on #5655:
1. Extract the duplicate 5-branch aria-label conditional into a shared
helper `thinkToggleAriaLabel` (plus a parallel `thinkEffortAriaLabel`
for the reasoning-effort dropdown). Both `thread.tsx` and
`shared-composer.tsx` now import from
`components/assistant-ui/think-aria-label.ts`.
2. While reviewing the diff, an Opus reviewer noticed the same
conceptual bug existed in the reasoning-effort dropdown branch in
`thread.tsx:627` (the alternate render path used by Claude-style
models with effort levels): before a model loaded, the aria-label
announced e.g. "Reasoning effort: medium" on a disabled, grayed-out
button. Same contradiction as the original bug for the on/off
toggle. Now routed through `thinkEffortAriaLabel`, which falls back
to "Thinking (model not loaded)" / "Thinking (not supported by this
model)" while the button is unreachable and only emits the effort
label when the model is loaded and actually supports reasoning.
3. Locked-on stays intentionally absent from `thinkEffortAriaLabel`:
the dropdown remains interactive in that case (users can still pick
an effort level), so the per-level label is the right announcement.
Verified by bun run typecheck (clean) and bun run build (clean). Bundle
confirms all six label strings still ship.
* studio/frontend: route shared composer effort dropdown through thinkEffortAriaLabel
12/12 reviewers flagged that the earlier think-aria-label helper was only wired into thread.tsx; the parallel reasoning-effort dropdown in shared-composer.tsx still hard-coded the raw "Reasoning effort: medium" label, so screen readers heard a stale effort value when the control was disabled (no model loaded, unsupported reasoning).
Route shared-composer's effort button through the same helper, matching thread.tsx.
* studio/frontend: shorten think-aria-label helper comments
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Co-authored-by: danielhanchen <michaelhan2050@gmail.com>
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