OpenAI shipped GPT Image 2.5 on 2026-09-08 as two model IDs rather than one:
flare is tuned for speed, sunburst for editing precision. Both accept text and
image input and run on /images/generations, /images/edits and the Responses
API, which is the path the native image_generation tool already uses.
Flare replaces gpt-image-2 as the default because OpenAI reports higher quality
at roughly half the latency, which suits create_image's one-shot call. Both
gpt-image-2 and gpt-image-1.5 stay on the whitelist, so a saved image_model
keeps working untouched.
Also in this change:
- The rejection message is now built from the whitelist itself instead of a
hand-written string that drifts whenever a model is added.
- codex_build.go uses the DefaultImageModel constant instead of hardcoding
"gpt-image-2", so the inline chat path cannot drift from the shared default.
- Both new models join the isEditModel branch so reference images route to
/images/edits.
- ParamField gains an optional labelKey, letting the dropdown read its label
from i18n instead of showing English inside a translated UI. It passes a
defaultValue, so a missing key degrades to the literal rather than breaking.
- Locale keys added to all five catalogs; ko was missing the whole
mediaChain.imageModel* group.
Surface parity: the desktop UI is unchanged because sortable-provider-card
renders no param form and passes params through as Record<string, unknown>.
The CLI is unchanged because cmd/ exposes no image-model flag. The API contract
is unchanged because image_model lives in the free-form params map; only the
backend whitelist widened.
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
