What problem does it solve? Code tells you what a system does now, but not why it was built that way. Over time, the constraints, trade-offs, and stakeholder requests behind past decisions are forgotten, causing developers to repeat mistakes or undo intentional design choices. This Skill preserves the "why" of development in a structured history archive. ## Core Features & Use Cases - Phase-based history: Records each development phase's background, goals, architecture decisions, technical constraints, and known tech debt in phase-N.md files. - Request tracking: Captures stakeholder or issue-driven requests in requests/ files, separating what was implemented from remaining constraints and unimplemented reasons. - Timeline overview: Maintains a _timeline.md summarizing the overall development flow and major architecture decisions across phases. - Use Case: Before refactoring a module, ask why it was designed a certain way; the Skill surfaces the original issue, the trade-offs accepted at the time, and which constraints still apply. ## Quick Start Record the development history for this completed phase, including the background, key changes, and the reasons behind the architecture decisions.