Conciseness

The body is ~15 lines with zero padding: every step ("Measure the release binary and capture cargo-bloat evidence", "Rebuild with identical release settings") earns its place and no concepts Claude already knows are explained, matching anchor 5 ("Lean and efficient; assumes Claude's competence; every token earns its place"). It is not anchor 4 because there are no instances of over-explanation to trim.

Actionability

The workflow is conceptually concrete — naming cargo-bloat, release settings, and candidate categories ("dependency, monomorphization, feature, or codegen contributor") — but no executable commands are given (e.g., the actual `cargo bloat --release` invocation, the build command, or how to measure and compare binary size), matching anchor 3 ("Some concrete guidance but incomplete; missing key details"). It is not anchor 4 because a practitioner could not run the measurement step as written without filling in commands themselves.

Workflow Clarity

The seven steps form a clear, well-sequenced loop with an explicit validation gate ("Keep the change only when size improves and verification passes") and a termination criterion ("Repeat until the target is met or remaining candidates have poor tradeoffs"), matching anchor 4 ("Clear sequence with most checkpoints present; minor validation gaps"). It falls short of anchor 5 because the error-recovery path is implicit — there is no explicit 'if verification fails, revert the change and try the next candidate' instruction, and how verification is performed is unspecified.

Progressive Disclosure

This is a simple skill under 50 lines with no bundle files (no references/, scripts/, or assets/ directories exist), and the body is a single well-organized section whose content is appropriately complete in-line; per the rubric's simple-skill guideline this matches anchor 5. The only cross-reference (`review`) is to another skill/command, not a nested bundle file, so there are no buried or multi-level references.

Specificity

The description names the domain and method concretely — "reduce Fallow binary size using cargo-bloat and release-build measurements" — but describes a single goal with its instrumentation rather than listing several distinct actions, matching anchor 3 ("Names domain and 1-2 concrete actions, but not comprehensive"). It does not reach anchor 4 because there is no enumeration of multiple operations (e.g., measuring, selecting contributors, reverting) that a fuller description would list.

Completeness

The 'what' is clear — iteratively reduce binary size with cargo-bloat and release measurements while preserving features, performance, and compatibility — but there is no 'when' clause at all (no "Use when..." or equivalent trigger guidance), which caps completeness at 3 per the judging guidelines. This matches anchor 3 ("Has a clear 'what' but 'when' is missing or only weakly implied"); it cannot be 4 without any explicit usage-trigger phrasing.

Trigger Term Quality

Strong natural terms are present — "binary size", "reduce", "cargo-bloat", "release-build" — which a user asking to slim a Rust binary would plausibly say, matching anchor 4 ("Good keyword coverage; a few natural terms missing"). It falls short of anchor 5 because common synonyms such as "shrink", "strip", "slim down", or "binary is too big" are absent.

Distinctiveness Conflict Risk

The description carves out a clear niche — Fallow binary size reduction via cargo-bloat — with minimal overlap risk against other skills, matching anchor 5 ("Clear niche with distinct triggers; minimal conflict risk"). Anchor 4 would require some overlap with closely related skills, which the project-specific scoping here avoids.