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
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npx tessl i github:actionbook/rust-skills --skill m04-zero-cost89
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Discovery
72%Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.
This description excels at trigger term coverage and distinctiveness, making it easy for Claude to identify when to use this skill for Rust generics/traits work. However, it lacks concrete action verbs describing what the skill actually does - it reads more like a keyword list than a capability description. The 'what' portion needs expansion to explain the specific help provided.
Suggestions
Add concrete action verbs describing capabilities, e.g., 'Resolves trait bound errors, implements generic functions, explains monomorphization, converts between static and dynamic dispatch'
Restructure to lead with capabilities before triggers: 'Helps implement and debug Rust generics and traits, resolve type errors, and optimize with zero-cost abstractions. Use when...'
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Names the domain (Rust generics/traits) and mentions 'zero-cost abstraction' but doesn't list concrete actions like 'implement traits', 'define generic functions', or 'resolve type errors'. The description focuses on triggers rather than capabilities. | 2 / 3 |
Completeness | The 'when' is well-covered with explicit 'Triggers:' section and 'CRITICAL: Use for' clause. However, the 'what does this do' is weak - it only says 'generics, traits, zero-cost abstraction' without explaining what actions Claude will perform with these concepts. | 2 / 3 |
Trigger Term Quality | Excellent coverage of natural terms including error codes (E0277, E0308, E0599), technical terms users would search for (generic, trait, impl, dyn, where, monomorphization), and even Chinese translations (泛型, 特征). These are terms Rust developers would naturally use. | 3 / 3 |
Distinctiveness Conflict Risk | Highly distinctive with Rust-specific error codes (E0277, E0308, E0599) and specialized terminology (monomorphization, static/dynamic dispatch, impl Trait). Very unlikely to conflict with non-Rust skills. | 3 / 3 |
Total | 10 / 12 Passed |
Implementation
100%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This is an exemplary skill file that demonstrates excellent information density through strategic use of tables, clear decision frameworks, and concrete code examples. It respects Claude's intelligence by focusing on decision-making guidance rather than explaining basic Rust concepts. The trace up/down pattern provides excellent workflow clarity for navigating between abstraction levels.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | Extremely lean and efficient. Uses tables extensively to compress information, avoids explaining what generics or traits are, and assumes Claude understands Rust fundamentals. Every section delivers actionable value without padding. | 3 / 3 |
Actionability | Provides concrete, executable Rust syntax examples, specific error codes with fixes, and clear decision tables. The syntax comparison section shows copy-paste ready code patterns for both static and dynamic dispatch. | 3 / 3 |
Workflow Clarity | Clear decision flows with 'Trace Up' and 'Trace Down' sections that guide through the thought process. The 'Thinking Prompt' provides explicit sequenced questions to ask before making design decisions. | 3 / 3 |
Progressive Disclosure | Well-organized with clear sections progressing from core concepts to quick reference to decision guides. Related skills are clearly signaled at the end with one-level-deep references to other modules (m05, m09, m10, m07). | 3 / 3 |
Total | 12 / 12 Passed |
Validation
75%Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.
Validation — 12 / 16 Passed
Validation for skill structure
| Criteria | Description | Result |
|---|---|---|
description_trigger_hint | Description may be missing an explicit 'when to use' trigger hint (e.g., 'Use when...') | Warning |
metadata_version | 'metadata' field is not a dictionary | Warning |
license_field | 'license' field is missing | Warning |
frontmatter_unknown_keys | Unknown frontmatter key(s) found; consider removing or moving to metadata | Warning |
Total | 12 / 16 Passed | |
- Reviewed
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