Name: core-animation
Rating: 57.599999999999994 (1 reviews)
Author: Prisma-Labs-Dev

core-animation

API reference: Core Animation (QuartzCore). Query for CALayer, CAAnimation, CABasicAnimation, CAKeyframeAnimation, CASpringAnimation, CATransaction, CAShapeLayer, CAGradientLayer, CAEmitterLayer, CATransform3D, CADisplayLink.

Quality

66%

Does it follow best practices?

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Securityby

Low

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tessl review fix ./skills/core-animation/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.

The body is a clean, well-structured reference skill: concise, actionable via concrete file pointers and fetch commands, with a clear scope/boundary section and an ordered doc-fallback workflow. Its main gap is that the many .md files it references are not actually present in the bundle.

Suggestions

Ensure the referenced .md files (calayer.md, cabasicanimation.md, etc.) actually exist in a bundle directory so the file table is not pointing at missing references.

Add a short 'Fetch a specific symbol page' example command so the remote-fetch fallback is copy-paste ready rather than only described.

Consider one tiny inline code snippet for the most common task (e.g. a CABasicAnimation on strokeEnd) to lift actionability from 4 to 5.

Dimension	Reasoning	Score
Conciseness	The body is lean and assumes Claude's competence (no explanation of what Core Animation is), with only minor phrasing that could be trimmed; it avoids padded concept explanations.	4 / 5
Actionability	It gives concrete guidance: a file-to-content table, explicit fetch commands (sosumi.ai mirror URL, pnpm fetch-doc), and specific symbol-level examples like CATransaction.setDisableActions(true), with only minor gaps in executable coverage.	4 / 5
Workflow Clarity	The 'Fetching More Docs' section lays out a clear three-step fallback sequence (local files -> other installed skills -> remote fetch), and the skill is non-destructive so the missing explicit validation checkpoint is a minor gap rather than a cap.	4 / 5
Progressive Disclosure	The SKILL.md is a well-organized overview with a one-level-deep file table mapping each .md reference to its content and clear navigation; structure is good with only minor organization gaps, though the referenced bundle files are not present in the bundle directories.	4 / 5
	Total	16 / 20 Passed

Description

58%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.

The description is specific and well-scoped to a distinct technical niche, but it leans on symbol-name jargon rather than natural user triggers and lacks an explicit 'Use when' clause, leaving its 'when' guidance only implied.

Suggestions

Add an explicit 'Use when...' clause naming the natural situations that call for this skill (e.g. animating a layer property directly, particle systems, per-frame CADisplayLink callbacks).

Include natural-language trigger terms users would say ('layer animation', 'core animation', 'explicit keyframe animation') alongside the symbol list, rather than jargon only.

Briefly note the boundary against SwiftUI/UIKit declarative animation so the description itself signals when NOT to use this skill.

Dimension	Reasoning	Score
Specificity	The description names a clear domain ('Core Animation (QuartzCore)') and lists numerous concrete capabilities via specific class names (CALayer, CABasicAnimation, CAKeyframeAnimation, etc.), giving several specific actions with only minor coverage gaps.	4 / 5
Completeness	It clearly states 'what' (an API reference for Core Animation with listed classes), but there is no explicit 'Use when...' trigger clause, which per the guidelines caps completeness at 3.	3 / 5
Trigger Term Quality	It enumerates symbol names rather than natural phrases a user would actually say; terms like 'CALayer' or 'CATransform3D' are technical jargon, and common variations or synonyms are missing.	3 / 5
Distinctiveness Conflict Risk	The QuartzCore/Core Animation niche is clear and distinct from adjacent UIKit/SwiftUI animation skills, with only minor overlap risk for closely related layer animation topics.	4 / 5
	Total	14 / 20 Passed

Validation

93%

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 — 15 / 16 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	15 / 16 Passed

Repository: Prisma-Labs-Dev/apple-skills
Path: skills/core-animation/SKILL.md
Commit: 4986260

Reviewed: 3 days ago

Table of Contents

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