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favicon

Generate favicons from a source image

Quality

69%

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

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

Quality

Content

68%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 skill body is highly actionable with complete ImageMagick commands, a thorough framework detection table, and exact manifest/HTML payloads, organized in a clear step sequence. Its main weaknesses are the missing post-generation verification for a file-overwriting batch workflow, a phantom 'AskUserQuestionTool' reference, and a duplicated HTML block that adds tokens.

Suggestions

Add a verification step after generation (e.g., confirm each output file exists and is non-empty, and re-check the edited HTML head) to close the feedback loop for this batch, file-overwriting workflow.

Replace the non-existent 'AskUserQuestionTool' with an instruction to simply ask the user in plain text, which is executable as written.

Deduplicate the HTML link-tag block (referenced in both the Rails and 'No Project Detected' sections) by defining it once and referencing it, trimming redundant tokens.

DimensionReasoningScore

Conciseness

The body is almost entirely commands, tables, and config blocks with no explanation of concepts Claude already knows, but the identical HTML link-tag block is duplicated (Rails and 'No Project Detected' sections) and a few phrases like "It's better to ask than to put files in the wrong place" could be trimmed, fitting the 'efficient with minor trimmable instances' anchor rather than 'every token earns its place'.

4 / 5

Actionability

Provides copy-paste-ready magick commands for every output file, exact manifest JSON, exact HTML tags, and a framework-detection table, but minor gaps exist: 'AskUserQuestionTool' is not a real tool name (unexecutable as written) and [STATIC_DIR] requires substitution, matching 'mostly executable guidance with minor gaps' rather than fully executable.

4 / 5

Workflow Clarity

The 8-step sequence is clear with prerequisite and source-image validation plus an error-handling section, but this is a batch operation that overwrites existing favicon files and rewrites HTML head tags, and it lacks a post-generation verification step or fix-and-retry feedback loop — the judging guideline caps batch/destructive workflows without validation at 3.

3 / 5

Progressive Disclosure

No bundle files exist and the single SKILL.md is well-organized with clear sections; however, at ~220 lines the per-framework HTML update details could live in a reference file, matching 'good structure, most content appropriately placed' rather than the clear-overview-with-references pattern of a 5.

4 / 5

Total

15

/

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 and clearly states the core action in third person, but it undersells the skill's full scope (manifest and HTML updates) and lacks any 'when to use' trigger guidance or common synonyms like site icon. Distinctiveness is excellent thanks to the unambiguous 'favicon' term.

Suggestions

Expand the description to cover the full capability set, e.g., "Generates a complete favicon set (ico, png, svg, apple-touch-icon, web manifest) from a source image and updates HTML link tags".

Add an explicit trigger clause such as "Use when the user asks to create favicons, site icons, or app icons for a project".

Include common synonyms and related terms (site icon, browser icon, touch icon) to improve trigger matching.

DimensionReasoningScore

Specificity

Names the domain and one concrete action ("Generate favicons from a source image") but omits the manifest creation and HTML link-tag updating that the skill performs, matching the anchor for 1-2 concrete actions without comprehensive coverage.

3 / 5

Completeness

The 'what' is clear (generate favicons from a source image) but there is no 'Use when...' clause or equivalent trigger guidance, which caps completeness at 3 per the judging guideline.

3 / 5

Trigger Term Quality

"favicons" is the natural user term and "source image" is relevant, but common variations users would say ("site icon", "app icon", "browser icon", "touch icon") are missing, fitting the 'some relevant keywords but missing synonyms' anchor.

3 / 5

Distinctiveness Conflict Risk

"favicon" is a sharply distinct niche term; a user mentioning favicons would unambiguously match this skill with minimal overlap risk against other image-manipulation skills.

5 / 5

Total

14

/

20

Passed

Validation

87%

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

Validation — 14 / 16 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

14

/

16

Passed

Repository

administrakt0r/AI-Agents-Safe-Coding-Skills

Path

skills/favicon/SKILL.md

Reviewed

Table of Contents

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