Conciseness

The body is dense and efficient: decision tables, terse rules with one-line rationales, and compact code blocks with no padding or explanation of concepts Claude already knows. Minor redundancy keeps it from anchor 5 — the 'Valid Models' section largely repeats the tier lists already encoded in the fallback chains, and spawn-format guidance overlaps between sections.

Actionability

Guidance is fully executable: a first-match-wins layer table, explicit role-to-model mappings with override conditions, literal fallback chains to copy, a ready-to-use spawn parameter template, and worked examples covering override, refactor, and mechanical cases. Claude can act on this without inferring anything.

Workflow Clarity

The multi-step process is explicitly sequenced ('Check these layers in order — first match wins'), complexity adjustments are bounded ('apply at most ONE — no cascading'), and failure recovery is a defined feedback loop: retry the fallback chain, max 3 retries, then omit the model parameter, with logging. No destructive or batch operations are involved, so no validation cap applies.

Progressive Disclosure

This is a single-file skill with no bundle directories, and the body is well organized into Context, Patterns, Examples, and Anti-Patterns with clear headers and no nested references. It is not a 5 because at ~135 lines the role-to-model and fallback-chain reference tables could reasonably live in separate one-level-deep files, keeping SKILL.md as a leaner overview.

Specificity

The description names the domain ('Per-agent model selection') and two structural components ('4-layer hierarchy', 'fallback chains'), but describes structure rather than concrete actions the skill performs. It matches anchor 3 (domain plus 1-2 concrete elements, not comprehensive); it is not 4 because it lists no specific capabilities beyond naming the hierarchy, and not 2 because the domain is clearly and specifically named.

Completeness

It has a reasonably clear 'what' (selects a model per agent via a hierarchy and fallback chains) but no 'when' guidance at all — no 'Use when...' clause or equivalent trigger. Per the judging guidelines, a missing trigger clause caps completeness at 3; it is not 2 because the 'what' is not vague.

Trigger Term Quality

Only 'model selection' is a phrase a user might naturally say; '4-layer hierarchy' and 'fallback chains' are internal jargon, and common natural phrases like 'which model', 'use opus', 'save costs', or 'pick a model' are absent. This fits anchor 2 (one or two keywords present, missing the natural phrases users say) better than 3, which expects broader relevant keyword coverage.

Distinctiveness Conflict Risk

'Per-agent model selection with 4-layer hierarchy and fallback chains' carves a fairly specific niche around agent spawning, so it is mostly distinct with only minor overlap risk against other orchestration or model-configuration skills. It falls between anchors 3 and 5, noticeably above the midpoint, so 4.