platform-design

300+ design rules from Apple HIG, Material Design 3, and WCAG 2.2 for cross-platform apps. Useful when shipping a single design across iOS, Android, and the web.

Quality

66%

Does it follow best practices?

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Securityby

Passed

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tessl review fix ./skills/platform-design/SKILL.md

Quality

Content

57%Weight 40%Scale 1-3

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, concise catalogue entry that appropriately points one level deep to an upstream repo with no nested references. Its core weakness is actionability: it tells the agent to install and invoke an upstream bundle without providing any concrete install paths, commands, or copy-paste-ready guidance, leaving the actual workflow underspecified.

Suggestions

Add a concrete install command or the exact target skills-directory path so the agent can install the upstream bundle without inspecting the README first.

Inline one or two representative rules or a direct deep link to a specific rules file so the skill provides immediate value instead of only pointing outward.

Replace the `open <url>` browser command with a `git clone`/download command plus the precise bundle path, turning the pointer into executable guidance.

Dimension	Reasoning	Score
Conciseness	The body is lean and under 30 lines, never explaining concepts Claude already knows (no primer on what HIG/Material/WCAG are); it respects the token budget even though the 'What it does' section repeats the frontmatter description, fitting the level-3 'lean and efficient; assumes Claude's competence' anchor.	3 / 3
Actionability	The only command is `open https://github.com/ehmo/platform-design-skills`, which merely opens a README in a browser; the actual install ('install the upstream bundle into your active agent's skills directory') and invocation steps have no concrete commands or paths, matching the level-1 'describes rather than instructs; no concrete code/commands' anchor.	1 / 3
Workflow Clarity	A loose two-step sequence is implied (install the upstream bundle, then invoke by name or trigger phrase), but the actual install mechanics are omitted and there are no concrete checkpoints, fitting the level-2 'sequence present but checkpoints missing' anchor rather than the fully-specified level-3.	2 / 3
Progressive Disclosure	The body is a short, well-organized overview with clearly labeled sections (What it does, Source, How to use) and a single well-signaled one-level reference to the upstream repo URL, with no nested indirection, matching the level-3 anchor for a sub-50-line skill.	3 / 3
	Total	9 / 12 Passed

Description

75%Weight 40%Scale 1-3

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 concise, third-person, and clearly answers both what the skill contains and when to use it, with a distinct cross-platform design niche. Its main weakness is that it describes a catalogue of rules rather than concrete actions, and the most natural trigger phrases are isolated in the frontmatter rather than woven into the description.

Dimension	Reasoning	Score
Specificity	The description names the domain and concrete sources ("Apple HIG, Material Design 3, and WCAG 2.2" for "cross-platform apps") but lists no actual actions a user can take, so it sits at the 'names domain and some actions, but not comprehensive' anchor rather than the multi-action level 3.	2 / 3
Completeness	It answers both what ("300+ design rules from Apple HIG, Material Design 3, and WCAG 2.2") and when via the explicit clause "Useful when shipping a single design across iOS, Android, and the web", satisfying the level-3 'what AND when with explicit triggers' anchor.	3 / 3
Trigger Term Quality	It surfaces relevant natural keywords ("Material Design 3", "WCAG 2.2", "Apple HIG", "cross-platform") but the broadest common variations live in the separate `triggers` frontmatter field rather than the description text, matching 'some relevant keywords but missing common variations'.	2 / 3
Distinctiveness Conflict Risk	The cross-platform design-system niche anchored to specific named standards (HIG, Material 3, WCAG 2.2) is a clear, distinct trigger surface unlikely to collide with other skills, matching the level-3 'clear niche with distinct triggers' anchor.	3 / 3
	Total	10 / 12 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: nexu-io/open-design
Path: skills/platform-design/SKILL.md
Commit: a2ba3ee

Reviewed: 6 days ago

Table of Contents

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