Conciseness

Every section carries skill-specific doctrine Claude would not self-supply ("A figure contains its own counter-evidence more often than the text does: a curve that crosses later, an error bar wider than the gap between compared methods, a log axis hiding a constant-factor difference") rather than explanations of known concepts. Lean 48-line overview with no padding and no time-sensitive details; nothing trimmable without losing instruction.

Actionability

The workflow is fully executable as instruction: "Record disagreements between the body and the appendix as findings", "follow each key formula with a micro-example using concrete numbers carried to the end", "When no such control exists, write that the paper does not run it". Per the rubric's scoring note, an instruction-only skill is not penalized for lacking code when guidance is this concrete, and specific failure-mode examples cover the common cases.

Workflow Clarity

Seven clearly sequenced steps (whole-source read → reconstruct path → load-bearing separation → ground math → evidence boundary → hedging → deliver) with explicit checkpoints embedded: record disagreements as findings, name missing controls, and "State the scope read — body, appendix, supplementary, or a stated subset — and never imply fuller coverage than was achieved". Reading is neither destructive nor batch, so the validation cap does not apply; checkpoints are explicit, not implicit, so this is above anchor 4.

Progressive Disclosure

Good structure overall: two verified one-level-deep in-bundle references loaded at point of need ("See `references/deep-reading-protocol.md`", "See `references/evidence-boundary.md`", both real files, each self-signaling when to load). However, the third referenced path — "Load `../nature-shared/core/paper-type-taxonomy.md` when the type is not obvious" — does not exist anywhere on the filesystem, a dangling conditional load. That is the 'minor organization gaps' of anchor 4 rather than the clean navigation of anchor 5.

Specificity

The description enumerates five concrete, distinct actions — "Recovers the real starting point and the bet the authors placed, separates load-bearing design from decoration, grounds each key formula in a worked micro-example with concrete numbers, and checks how far the evidence actually reaches" — plus a concrete deliverable ("Delivers a structured Markdown long-read by default"), all in third person. This is comprehensive coverage of the skill's actions, matching the anchor-5 example rather than the 'several actions with minor gaps' of anchor 4.

Completeness

Both what and when are explicitly answered: the what is the enumerated action list, and the when is an explicit trigger clause — "Use for 精读论文, … and deep single-paper comprehension before building on, reviewing, presenting, or citing that paper" — with concrete trigger phrases. Not 4, because the when-clause is explicit and specific rather than improvable-vague.

Trigger Term Quality

Highly natural user phrasings are present — "精读论文", "讲透这篇论文", "把这篇读懂", "作者为什么这么设计", "这个公式怎么推出来的" — but English coverage leans on the skill's own name ("paper x-ray") and the stilted "deep single-paper comprehension"; plain-English variants a user would actually say ("explain this paper", "walk me through this paper") are missing. Falls between anchor 4 ('good keyword coverage; a few natural terms missing') and anchor 5, so 4 fits best.

Distinctiveness Conflict Risk

A clear niche (deep single-paper comprehension) with distinct bilingual triggers, further fenced by explicit negative scope ("Not a summary, not a translation, not a peer review"), which disambiguates it from sibling reading/review/translation skills. Minimal conflict risk, matching anchor 5.