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favicon

Generate favicons from a source image

51

Quality

58%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./skills/favicon/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

71%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

This is a highly actionable and well-structured skill with excellent executable guidance for favicon generation across multiple frameworks. Its main weaknesses are length (could benefit from splitting framework-specific details into separate files) and some verbosity in areas where Claude could infer behavior. The workflow is clear and well-sequenced but lacks an explicit post-generation validation step.

Suggestions

Split framework-specific HTML update instructions (Step 7) into a separate FRAMEWORKS.md reference file to reduce the main skill's length and improve progressive disclosure.

Add a brief validation step after Step 5 to verify generated files exist and have non-zero size (e.g., `ls -la [STATIC_DIR]/favicon*`).

Consolidate the framework detection table into a more compact format or move it to a separate reference file, keeping only the most common frameworks inline.

DimensionReasoningScore

Conciseness

The skill is quite long (~200 lines) and includes some information Claude could infer (e.g., explaining what title case means, basic file existence checks). The framework detection table is useful but verbose. The HTML snippets are repeated for multiple frameworks when they're nearly identical. However, much of the content is genuinely necessary domain-specific knowledge (flag ordering for ImageMagick, framework-specific static directories).

3 / 5

Actionability

Excellent actionability throughout. Every ImageMagick command is copy-paste ready with exact flags and arguments. The framework detection table gives specific file markers. HTML snippets and Next.js metadata exports are complete and executable. The manifest JSON is fully specified. Critical details like `-background none` flag ordering are called out.

5 / 5

Workflow Clarity

The 8-step workflow is clearly sequenced and logically ordered (prerequisites → validate → detect → generate → update → summarize). Error handling is covered in a dedicated section. However, there's no explicit validation checkpoint after generating the favicon files (e.g., verifying the generated files exist and have expected sizes), which is a minor gap for a file-generation workflow. The 'ask when in doubt' guidance is a good safety measure.

4 / 5

Progressive Disclosure

The skill is a monolithic document with no references to supporting files. The framework-specific HTML update instructions (Rails, Next.js, Static HTML) and the large framework detection table could be split into separate reference files. For a skill of this length (~200 lines of substantive content), the lack of any file splitting is a missed opportunity, though the section headers provide reasonable internal navigation.

3 / 5

Total

15

/

20

Passed

Description

45%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 and identifies a clear niche (favicon generation), which helps with distinctiveness. However, it lacks a 'Use when...' clause, misses common trigger terms and synonyms, and provides minimal detail about the specific capabilities or outputs involved.

Suggestions

Add a 'Use when...' clause with trigger terms like 'favicon', 'site icon', 'browser icon', 'favicon.ico', '.ico'.

Expand the capability description to mention specific outputs such as multiple sizes, ICO format, PNG variants, or web manifest entries.

Include common synonyms and file extensions users might mention, e.g., 'tab icon', 'website icon', '.ico', '.png'.

DimensionReasoningScore

Specificity

Names the domain (favicons) and one concrete action (generate from a source image), but lacks detail on what formats, sizes, or outputs are produced (e.g., ICO, PNG, multi-size, manifest files).

3 / 5

Completeness

Provides a basic 'what' (generate favicons from a source image) but has no 'when' clause or trigger guidance. Per rubric guidelines, a missing 'Use when...' clause caps completeness at 3, and the 'what' is also quite thin, placing this at a 2.

2 / 5

Trigger Term Quality

Includes 'favicons' and 'source image' which are relevant keywords, but misses common synonyms and related terms like 'favicon.ico', 'site icon', 'browser icon', 'tab icon', or file extensions like '.ico'.

3 / 5

Distinctiveness Conflict Risk

Favicons are a fairly specific niche, making this unlikely to conflict with most other skills. However, it could overlap with general image processing or icon generation skills without clearer boundary language.

4 / 5

Total

12

/

20

Passed

Validation

81%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation9 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

allowed_tools_field

'allowed-tools' contains unusual tool name(s)

Warning

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

9

/

11

Passed

Repository
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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