When this skill is invoked:

1. Parse Arguments

Four modes:

Full spec: /setup-engine godot 4.6 — engine and version provided
Engine only: /setup-engine unity — engine provided, version will be looked up
No args: /setup-engine — fully guided mode (engine recommendation + version)
Refresh: /setup-engine refresh — update reference docs (see Section 10)
Upgrade: /setup-engine upgrade [old-version] [new-version] — migrate to a new engine version (see Section 11)

Recognized engine keywords: godot, unity, unreal, threejs (Three.js / React Three Fiber — Web 3D), pixijs (PixiJS — Web 2D interactive), phaser (Phaser 4 — Web 2D games). The web engines use language JS/TS; /setup-engine threejs, /setup-engine pixijs, and /setup-engine phaser resolve directly to the templates in Sections 4–5.

2. Guided Mode (No Arguments)

If no engine is specified, run an interactive engine selection process: