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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.

46

Quality

57%

Does it follow best practices?

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SecuritybySnyk

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tessl review fix ./skills/platform-design/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

40%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 well-organized, brief catalogue entry that honestly defers content to the upstream repo, but it provides almost no executable guidance — no install command, no sample rules, and no invocation verification. As a result actionability and workflow clarity sit near the bottom of the scale.

Suggestions

Replace 'install the upstream bundle into your active agent's skills directory' with a concrete, copy-pasteable command (e.g. a git clone or install command with the exact target path).

Inline a short quick-start subset (5-10 of the highest-value rules) so the skill delivers value even before the upstream bundle is fetched.

Add a verification step to the workflow, e.g. checking that `platform-design` appears in the agent's skills listing before asking it to invoke the skill.

Drop the verbatim repeat of the frontmatter description in 'What it does' and use that space for the quick-start rules instead.

DimensionReasoningScore

Conciseness

The body is short and has no padding, but the 'What it does' section repeats the frontmatter description verbatim, and 'This catalogue entry advertises the skill in OpenDesign so the agent discovers it during planning' is meta-commentary that adds nothing to execution. Mostly efficient, with some content that could be tightened — anchor 3.

3 / 5

Actionability

The only concrete command is `open https://github.com/ehmo/platform-design-skills`, which does not perform the skill's task. 'Install the upstream bundle into your active agent's skills directory' gives no install command or path, so the user/agent cannot execute the actual workflow from this file. This matches 'Minimal concrete guidance; high-level hints but missing the specific steps to execute'.

2 / 5

Workflow Clarity

A rough sequence exists (inspect README → install bundle → invoke by name or triggers), but each step is vague: there is no install command, no verification that the skill is available, and no guidance on what to do once the skill is invoked. Steps are poorly defined and validation is absent — anchor 2.

2 / 5

Progressive Disclosure

The body is under 50 lines with clean sections (What it does / Source / How to use) and appropriately defers the 300+ rules to an external upstream rather than inlining them — the pointer is clearly signaled and one level deep. It scores below 5 because there are no in-bundle reference files at all, so all substantive content lives outside the skill and navigation depends entirely on an external URL.

4 / 5

Total

11

/

20

Passed

Description

57%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 concise, distinct, and includes an explicit 'Useful when...' clause, but it describes a catalog of rules rather than any action the skill performs. Adding one or two concrete verbs (e.g., 'check your design against...' or 'apply...') would lift both specificity and completeness.

Suggestions

Add concrete action verbs, e.g. 'Check and apply 300+ design rules from Apple HIG, Material Design 3, and WCAG 2.2 to cross-platform apps.'

Add natural trigger synonyms such as 'accessibility', 'a11y', 'design guidelines', or 'design system' alongside the existing standard names.

Make the 'when' clause slightly more behavioral, e.g. 'Use when reviewing or building UI for iOS, Android, or the web, or when auditing a design for accessibility (WCAG) compliance.'

DimensionReasoningScore

Specificity

The description names the domain precisely ("300+ design rules from Apple HIG, Material Design 3, and WCAG 2.2 for cross-platform apps") but contains no verbs or concrete actions — it never says whether the rules are applied, checked, validated, or referenced. This matches the anchor 'Names the domain but actions are minimal or generic'.

2 / 5

Completeness

Both parts are present: 'what' ("300+ design rules from Apple HIG, Material Design 3, and WCAG 2.2") and an explicit 'when' ("Useful when shipping a single design across iOS, Android, and the web"). The when-clause is explicit and reasonably concrete, but the 'what' is a static inventory rather than a stated action, so it falls just short of the anchor-5 pattern of fully concrete what-and-when.

4 / 5

Trigger Term Quality

It includes strong domain keywords ("Apple HIG", "Material Design 3", "WCAG 2.2", "cross-platform", "iOS, Android, and the web") but misses natural variations users would say, such as "accessibility", "a11y", "design guidelines", "UI guidelines", or "design system". Some relevant keywords, but missing common variations — anchor 3.

3 / 5

Distinctiveness Conflict Risk

Naming three specific standards bodies (HIG, Material Design 3, WCAG 2.2) carves out a clear niche with distinct triggers, giving minimal conflict risk with generic design or UI skills. It is not a perfect 5 because broad triggers like 'platform design' or 'material design' could still overlap with other design-system or accessibility skills.

4 / 5

Total

13

/

20

Passed

Validation

93%

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

CriteriaDescriptionResult

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

Reviewed

Table of Contents

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