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skill-creator

Load this skill before creating, updating, or deleting a Vibe skill, or whenever you plan to add or modify SKILL.md files under a skills directory. It explains Vibe's SKILL.md frontmatter, discovery order, support files, and the permission flow.

71

Quality

89%

Does it follow best practices?

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Adds up to 20 points to the overall score

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SecuritybySnyk

Passed

No findings from the security scan

SKILL.md
Quality
Evals
Security

Quality

Content

80%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 well-organized, product-dense instruction body that gives exact paths, schemas, and procedures with almost no padding. Its main weakness is the absence of validation/verification checkpoints — most notably around the destructive delete workflow, which caps workflow clarity.

Suggestions

Add a validation checkpoint to destructive operations: before deleting, confirm the exact skill name and scope with the user (or verify the directory matches the requested skill) since 'remove the whole skill directory' is unrecoverable.

Add a post-write verification step for create/update, e.g. re-check that the frontmatter name matches ^[a-z0-9]+(-[a-z0-9]+)*$, the directory name matches the frontmatter name, and the description is within 1–1024 chars.

Trim the minor redundancy between the 'Where skills live' scope paragraph and the Create bullet, and drop the 'it is bewildering' justification to tighten conciseness.

DimensionReasoningScore

Conciseness

The body is dense with product-specific facts Claude cannot know (discovery order, frontmatter schema with regex and char limits, precedence rules) and avoids re-teaching known concepts, but has minor trimmable instances such as justifying the one-question rule ('it is bewildering') and near-duplicate scope guidance in two sections ('Choose the scope before writing... Ask the user which they want...' vs the Create bullet), matching the 'efficient with minor over-explanation' anchor rather than the every-token-earns-its-place anchor.

4 / 5

Actionability

Guidance is fully executable for an instruction-only skill: a copy-paste-ready SKILL.md template, exact directory paths per scope, the precise name regex and length limits, and per-operation procedures (create/update/delete). Anchor 4 ('minor gaps') does not apply — nothing a reader needs to act is left abstract.

5 / 5

Workflow Clarity

The requirement-gathering sequence is clear (ordered questions, skip answered ones, then scope then write), but validation checkpoints are absent throughout: the destructive delete operation ('remove the whole skill directory') has no confirm-before-delete or name-target verification step, and create/update have no post-write check that the frontmatter is valid. Per the rubric, a destructive workflow without validation is capped at 3; it is not a 2 because steps are concrete and correctly sequenced, not gapped.

3 / 5

Progressive Disclosure

This is a single-file skill (~110 lines) with no bundle files, and nothing is inlined that clearly belongs in a separate file; headers (Gathering requirements, What a skill is, Where skills live, SKILL.md format, Support files, Create/update/delete, Applying changes) make navigation trivial, which matches the simple-skill exception for well-organized single-file skills.

5 / 5

Total

17

/

20

Passed

Description

92%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 strong description that explicitly states both what the skill explains and when to load it, with concrete action verbs and product-specific trigger terms. Voice is appropriately third-person/imperative with no fluff or over-claims.

Suggestions

Add a synonym or two for common user phrasings, e.g. '...before making or editing a skill' alongside 'creating, updating, or deleting', to reach comprehensive trigger coverage.

Consider mentioning the slash-command angle ('/skill-name') since users may ask about user-invocable skills rather than file authoring.

DimensionReasoningScore

Specificity

The description lists multiple concrete actions ('creating, updating, or deleting a Vibe skill', 'add or modify SKILL.md files') and comprehensively enumerates what it explains ('SKILL.md frontmatter, discovery order, support files, and the permission flow'), matching the comprehensive-coverage anchor rather than the minor-gaps anchor at 4.

5 / 5

Completeness

Both parts are explicit: 'what' is stated concretely ('It explains Vibe's SKILL.md frontmatter, discovery order, support files, and the permission flow') and 'when' is given with concrete trigger phrases ('Load this skill before creating, updating, or deleting a Vibe skill, or whenever you plan to add or modify SKILL.md files'), satisfying the equivalent of a 'Use when...' clause.

5 / 5

Trigger Term Quality

Good natural-term coverage: 'creating', 'updating', 'deleting', 'add or modify', 'Vibe skill', 'SKILL.md files', 'skills directory' — exactly the phrases a user would say. It sits just below the comprehensive anchor because a few plausible user phrasings (e.g. 'make a new skill', 'write a skill') are not covered as synonyms, matching the 'good coverage, a few natural terms missing' anchor.

4 / 5

Distinctiveness Conflict Risk

It occupies a clear niche — authoring Vibe skills / SKILL.md files — with triggers ('Vibe skill', 'SKILL.md files under a skills directory') that no other reasonable skill would claim, so conflict risk is minimal per the anchor 5 example.

5 / 5

Total

19

/

20

Passed

Validation

100%

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

mistralai/mistral-vibe

Path

vibe/plugins/builtins/vibe/skills/skill-creator/SKILL.md

Reviewed

Table of Contents

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If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.