m04-zero-cost

CRITICAL: Use for generics, traits, zero-cost abstraction. Triggers: E0277, E0308, E0599, generic, trait, impl, dyn, where, monomorphization, static dispatch, dynamic dispatch, impl Trait, trait bound not satisfied, 泛型, 特征, 零成本抽象, 单态化

Quality

79%

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Securityby

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tessl review fix ./skills/m04-zero-cost/SKILL.md

Quality

Content

75%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A dense, well-structured decision reference that assumes Claude's Rust knowledge and delivers concrete syntax and decision tables, with mild redundancy and room to factor out reference tables into bundle files.

Suggestions

Consolidate the two error-code tables (Error → Design Question and Error Code Reference) into one to remove redundancy.

Add a short validate/recover loop after the Trace sections, e.g. "if the error persists after applying the chosen pattern, re-check object safety / trait bounds."

Consider moving the Error Code Reference and Syntax Comparison into a references/ file to keep SKILL.md a lean overview.

Dimension	Reasoning	Score
Conciseness	Lean, table-and-code-driven content that assumes Rust competence with no padding; minor redundancy between the "Error → Design Question" table and the later "Error Code Reference" table covering the same E0277/E0308/E0599/E0038 codes.	4 / 5
Actionability	Provides executable Rust snippets (impl Trait, Box<dyn Trait>, fn foo<T: Trait>) and concrete scenario→choice→why decision matrices; falls short of fully copy-paste-ready complete examples covering common cases.	4 / 5
Workflow Clarity	Clear decision sequence (Core Question → Thinking Prompt → Trace Up/Down → Decision Guide) with conditional navigation, but lacks an explicit validate-and-recover feedback loop for the iterative design refinement it implies.	4 / 5
Progressive Disclosure	Well-organized single-file structure with clear section headers and a Related Skills cross-reference table; no bundle files exist so all content is inline, and some reference material (Error Code Reference, Syntax Comparison) could be split out.	4 / 5
	Total	16 / 20 Passed

Description

72%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A trigger-optimized description with excellent keyword coverage (error codes plus bilingual synonyms) and a clear niche, weakened only by listing domain topics rather than concrete capabilities.

Suggestions

Lead with a concrete action verb phrase, e.g. "Guides the choice between generics and trait objects for zero-cost abstraction in Rust," before the trigger list.

Keep the rich trigger list but ensure the "what it does" statement is distinct from the "when to use" clause.

Dimension	Reasoning	Score
Specificity	Names the domain ("generics, traits, zero-cost abstraction") but lists topic areas rather than concrete actions a user would observe, matching the 'names the domain but actions are minimal or generic' anchor.	2 / 5
Completeness	Both "what" (generics, traits, zero-cost abstraction) and "when" (explicit "Triggers:" clause with concrete phrases) are present; the "what" is topic-based rather than action-based so it does not fully reach the explicit-both anchor of 5.	4 / 5
Trigger Term Quality	Comprehensive natural-term coverage including error codes (E0277, E0308, E0599), English terms (generic, trait, impl, dyn, where, monomorphization, static/dynamic dispatch, impl Trait), and Chinese synonyms (泛型, 特征, 零成本抽象, 单态化).	5 / 5
Distinctiveness Conflict Risk	The Rust-specific error codes and "zero-cost abstraction" niche make it mostly distinct, though E0308 (type mismatch) and several trait terms overlap with related Rust type-system skills referenced in the body.	4 / 5
	Total	15 / 20 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: actionbook/rust-skills
Path: skills/m04-zero-cost/SKILL.md
Commit: 5c40d3a

Reviewed: 14 days ago

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