Conciseness

The body is dense and assumes competence — tables, checklists, and terse directives like '不给"较快"' with no concept explanations — but the '文档与下游的契约' per-role subsections preview data-model/interface/state-machine content already covered in feature-design-template.md, minor over-explanation that could be trimmed. Fits the 'efficient with minor trimmable instances' anchor rather than the every-token-earns-its-place of 5.

Actionability

Fully concrete guidance for an instruction-only skill: exact save paths ('markdown/<topic>-feature-design-<YYYYMMDD>.md'), Given/When/Then requirements with concrete numeric examples ('p99 ≤ 200ms、错误率 < 0.1%'), enumerated boundary inputs ('0、最大值、Unicode、SQL 注入字符、超长字符串'), and an explicit stop condition ('如果输入没有 PRD,先停下来问用户要 PRD').

Workflow Clarity

A clear 6-step sequence with an explicit validation step ('自检' with a 10-item checklist) and a feedback loop ('如果任一项不过,补完后再交付'), plus an upfront guard for missing input. Matches the anchor for clear sequence with explicit validation and error-recovery loops; step 4's sub-gaps are covered by the reference templates.

Progressive Disclosure

SKILL.md serves as a lean overview and all four referenced files (feature-design-template.md, api-spec-template.md, state-machine-template.md, test-matrix-template.md) exist in references/, are one level deep, and are clearly signaled with a purpose line and an explicit use-when ('深化"对外接口"章节时使用'). Matches the well-signaled one-level-deep anchor.

Specificity

Lists multiple concrete actions — translating a PRD into a testable design doc, explicitly surfacing '行为、状态、接口、数据、权限、异常、验收标准', and writing to 'markdown/ 目录' — but the rationale about tester isolation and downstream readers is padding rather than capability, so it sits between the comprehensive (5) and several-actions (4) anchors, closer to 4 given the verbosity guideline.

Completeness

Explicitly answers both: 'what' (translate PRD into a fully explicit, independently testable design doc with defined input and output location) and 'when' (the '适用于:' clause enumerates concrete trigger phrases). Matches the anchor requiring both with concrete trigger phrases.

Trigger Term Quality

The '适用于' list covers comprehensive natural synonyms users would actually say: '功能设计文档、技术设计文档、Tech Design、详细设计说明书、FDD、Functional Design Doc、Detailed Design、模块设计文档', plus task phrasings like '把 PRD 翻译成开发设计'. No common variation is missing, matching the comprehensive-synonyms anchor.

Distinctiveness Conflict Risk

The PRD-to-feature-design niche is distinct with mostly niche-specific triggers, but broad terms like '技术设计文档、Tech Design' could fire on general design-writing requests without a PRD — minor overlap risk with closely related skills, not the clear-niche-minimal-conflict of 5 nor the broader overlap of 3.