Destiny is a Claude Code plugin that integrates classical East Asian astrology, computing Eight Characters (BaZi) birth charts, daily pillars, I-Ching hexagrams, and five-element relationships via a deterministic Python backend. The same person plus same date always yields identical numerical outputs, with LLM interpretation layered separately on top. Practitioners curious about agentic tool-use patterns or Claude Code slash-command plugin architecture will find the deterministic-plus-generative split instructive. Compared to pure LLM fortune outputs, the grounded computation layer reduces hallucinated numerology.