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.pi/skills/self-gating-systems/SKILL.md

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+# Intent-Based Architecture Skill
+
+Read the architecture document at `docs/self-gating-systems.md` (resolve relative to the project root `/home/jonas/projects/snow_trail_sdl/`) and follow its patterns when:
+
+- Adding cross-system communication (use intents, not direct function calls)
+- Adding new systems to the main loop
+- Changing how game modes work (editor, dialog, gameplay)
+- Working with camera, input, or mode-switching logic
+
+Key rule: **systems communicate through typed intent data in shared queues** — producers insert intents, consumers process and remove them. No system calls another system's functions directly.