Book Appendices

Supplementary case studies and deep-dive write-ups that don't fit the main chapter sequence but are useful reference material for understanding how this repository works and evolved.

• Skill Refactor with Fable 5 — a case study on how the intelligent-textbook skill library evolved since Claude Skills launched in October 2025, why it periodically needs re-architecting, and how a 29-skill, over-budget catalog was consolidated to 14 skills through an agent-authored, human-reviewed, phase-by-phase refactor.