v2.9.0 — purity-checklist reference + full-park purity audit

What's new

v2.9.0 combines two pieces: a new shared purity-checklist reference, and a full-park purity audit that applies it.

1. New reference: references/purity-checklist.md

An audit checklist for the purity principle — 16 checks across 5 categories (溯源残留 / 装饰冗余 / 死内容 / doc-impl 裂隙 / 语言平台残留). Complements engineering-principles.md (behavior discipline) with a "what to check" audit tool. Generic — applies to code, skill docs, README, any reference.

2. Full-park purity audit — 24 findings fixed

12 parallel agents audited all 47 skills against the checklist. 24 findings across 8 skills, all fixed:

Category	Count	Highlights
A 溯源残留	2	frontend-design merge-history & past-state narratives removed
B 装饰/冗余	4	tdd Not-for/Exceptions conflict resolved; verbatim trigger copies dropped; duplicated 'Faster is safer' removed
C 死内容	1	observability dead cross-skill link fixed (../incident-response/ → ${CLAUDE_PLUGIN_ROOT}/skills/09-operate/incident-response/)
D doc/impl 裂隙	13	research §9.1 enum drift; burn-rate window mismatch; brand-mode missing anti-tells ref; ADR path; styles count 18→21; auth/i18n/e2e/simplify/cost Verify-Steps gaps; using-skills phase-tree drift; ci-cd canary thresholds
E 语言/平台残留	4	跨-row→cross-row; 实战→'a later run'; popularity justification dropped; project-specific 'Default for this project' removed

Method

Per the skill's own clone-to-archive discipline, 3 deep-research frameworks (gpt-researcher, open_deep_research, STORM) were cloned into archive/ and analyzed to validate the research skill's spine — that analysis informed the genre boundary declaration in v2.8.1. The purity checklist then applied uniformly across all 47 skills via 12 parallel audit agents.

Files

• references/purity-checklist.md — NEW (16-check audit tool)
• 32 files across 8 skills — purity fixes (see commit de6e0a1 for the full breakdown)
• plugin.json, README.md, README.zh-CN.md — 2.8.1 → 2.9.0

Validator green: 47/47, 0 errors.

Full diff: v2.8.1...v2.9.0