## Summary
This updates the embedded `imagegen` system skill in `codex-rs/skills`
with the ImageGen 2 skill changes from `openai/skills-internal#87`.
The bundled skill now keeps normal image generation/editing on the
built-in `image_gen` path, updates the CLI fallback defaults to
`gpt-image-2`, and routes explicit transparent-output requests through
`gpt-image-1.5` with clear guidance that `gpt-image-2` does not support
transparent backgrounds.
## Details
- Update `SKILL.md` routing guidance for built-in vs CLI fallback
behavior.
- Update CLI/API references for `gpt-image-2` size constraints, quality
options, near-4K sizes, and unsupported options.
- Update `scripts/image_gen.py` defaults and validation:
- default model `gpt-image-2`
- default size `auto`
- default quality `medium`
- reject transparent backgrounds on `gpt-image-2`
- reject `input_fidelity` on `gpt-image-2`
- validate flexible `gpt-image-2` sizes and suggest `3824x2160` /
`2160x3824` for near-4K requests
- Update prompt/reference docs with the new model and routing guidance.
## Validation
- `cargo test -p codex-skills`
- `git diff --check`
- Manual CLI dry-runs for:
- default `gpt-image-2` payload
- `3824x2160` near-4K size acceptance
- `3840x2160` rejection with near-4K guidance
- transparent background rejection on `gpt-image-2`
- transparent background acceptance on `gpt-image-1.5`
- `input_fidelity` rejection on `gpt-image-2`
Bazel target check was not run locally because `bazel` is not installed
in this environment.
Vaibhav SrivastavandGitHub
Dominik KundelandGitHub