Completes the model re-tiering from #2442: the gan-planner, gan-generator,
and gan-evaluator agents were already re-pinned to sonnet, but the
gan-style-harness script and docs still defaulted GAN_PLANNER_MODEL,
GAN_GENERATOR_MODEL, and GAN_EVALUATOR_MODEL to opus. Align the script
defaults, skill docs (en/ja/zh), and example commands with the landed
agent tiers. Opus remains available via the existing env overrides.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Implements Anthropic's March 2026 harness design pattern — a multi-agent
architecture that separates generation from evaluation, creating an
adversarial feedback loop that produces production-quality applications.
Components:
- 3 agent definitions (planner, generator, evaluator)
- 1 skill with full documentation (skills/gan-style-harness/)
- 2 commands (gan-build for full apps, gan-design for frontend)
- 1 shell orchestrator (scripts/gan-harness.sh)
- Examples and configuration reference
Based on: https://www.anthropic.com/engineering/harness-design-long-running-apps
Co-authored-by: Hao Chen <haochen806@gmail.com>
