Move the codex-imagegen wrapper out of scripts/ into its own workspace
package alongside baoyu-md, baoyu-chrome-cdp, and baoyu-fetch. Drop the
bash shim — src/main.ts now carries a `#\!/usr/bin/env bun` shebang and
serves as the sole entrypoint. Add scripts/sync-codex-imagegen.sh so
skills/baoyu-image-gen/scripts/codex-imagegen/ can be regenerated from
packages/baoyu-codex-imagegen/src/ for skill self-containment. Update
CLAUDE.md, docs/codex-imagegen-backend.md, and the CI workflow paths
accordingly.
Implements the preferred_image_backend: codex-imagegen config key
already referenced in several SKILL.md files but with no corresponding
backend. Bridges non-Codex runtimes (Claude Code, etc.) to Codex CLI's
built-in image_gen tool via 'codex exec'. Uses the user's Codex
subscription — no OPENAI_API_KEY required.
Reliability:
- Retry with exponential backoff (default 2 retries, configurable)
- 9 classified error kinds (retryable vs non-retryable)
- Node child_process timeout with SIGTERM→SIGKILL ladder
Correctness:
- Verifies image_gen was actually invoked (not bypassed) by checking
$CODEX_HOME/generated_images/{thread_id}/ for a PNG
- PNG magic byte validation
- Output file size sanity check
Observability:
- Structured JSONL logging with --log-file
- Verbose stderr mode with --verbose
- Returns thread_id, tool_calls, token usage in result JSON
- Raw codex event stream preserved per attempt for debugging
Efficiency:
- Idempotency cache via --cache-dir (sha256 of prompt+aspect+refs)
- Cache hit returns in <0.3s vs 50-90s cold
Features:
- --ref reference images (repeatable, passed through to codex exec --image)
- --retries, --retry-delay, --timeout all configurable
- File lock serializes concurrent invocations
Testing:
- 16 Bun unit tests across parser, cache, validator
- Path-filtered CI workflow at .github/workflows/codex-imagegen-tests.yml
- Composes with existing test.yml without conflicts
Architecture:
- scripts/codex-imagegen.sh: thin bash entrypoint (bun → npx -y bun fallback)
- scripts/codex-imagegen/: TypeScript module
- main.ts (orchestrator), types.ts (CliOptions/GenerateResult/GenError),
spawn.ts (child_process), parser.ts (JSONL events), validator.ts
(image_gen check + PNG magic), cache.ts (sha256 cache + FileLock),
logger.ts (JSONL structured logger)
Trade-offs documented in docs/codex-imagegen-backend.md:
- 5-10x slower than direct OpenAI API (or near-free on cache hit)
- ToS gray area: image_gen is documented for interactive use; non-
interactive invocation via codex exec is not explicitly addressed.
Suitable for personal low-volume use; users are responsible for
ensuring their usage complies with applicable terms of service.