CtrlK
BlogDocsLog inGet started
Tessl Logo

favicon-generator

Generate flat favicons from image prompts, then key out a magenta background and build PNG/ICO/WebP outputs with ImageMagick. Use when you need a reliable favicon workflow.

87

3.57x
Quality

80%

Does it follow best practices?

Impact

100%

3.57x

Average score across 3 eval scenarios

SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./tests/ext_conformance/artifacts/agents-mikeastock/skills/favicon-generator/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

86%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.

A lean, highly actionable skill body: concrete commands, a complete output inventory, tuning knobs, and a pitfalls section that doubles as error recovery. The only meaningful gaps are the unresolved external generation-script path and the lack of an explicit validation checkpoint before HTML integration.

DimensionReasoningScore

Conciseness

Every section is load-bearing instruction — prompt template, two command blocks, output list, env-var tuning, HTML/manifest snippets, and pitfalls — with no padding or explanations of concepts Claude already knows.

5 / 5

Actionability

"bash {baseDir}/scripts/faviconize.sh <input-png> <output-base>" and the FAVICON_KEY_COLOR/FAVICON_FUZZ tuning line are copy-paste ready, but the generation command's "<nanoBananaDir>" placeholder is only resolved via three example paths for an external skill, leaving a minor gap.

4 / 5

Workflow Clarity

The sequence (prereqs → prompt → generate at 1K then re-run at 2K/4K → convert → update HTML/manifest) is clear, and "Common pitfalls" supplies feedback loops like "Magenta bleeding into edges means... Regenerate"; however, there is no explicit in-flow checkpoint to inspect the transparent PNG before exporting and wiring up HTML.

4 / 5

Progressive Disclosure

This simple single-task skill keeps its only heavy logic correctly externalized in scripts/faviconize.sh (verified to exist and produce the documented outputs), with everything else appropriately inline under clean section headers and no nested references.

5 / 5

Total

18

/

20

Passed

Description

73%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.

A specific, well-scoped description that names concrete actions and an explicit trigger clause, with only minor gaps. Its weakest points are the second-person "when you need" phrasing and a "when" clause that restates the domain instead of listing concrete triggers.

Suggestions

Rewrite the trigger clause in third person with concrete triggers, e.g. "Use when the user asks for a favicon, site icon, or apple touch icon, or needs to make an existing logo work at 16×16".

Broaden trigger keywords with natural synonyms such as "site icon", "browser icon", and "apple touch icon" to improve both trigger coverage and completeness.

Mention the HTML/manifest integration step in the capability list so the "what" fully covers the workflow the body actually delivers.

DimensionReasoningScore

Specificity

"Generate flat favicons from image prompts", "key out a magenta background", and "build PNG/ICO/WebP outputs with ImageMagick" name several concrete actions (base 4), but the second-person phrasing "Use when you need..." triggers the guideline's 1-point specificity penalty.

3 / 5

Completeness

The description clearly answers "what" with the full pipeline and includes an explicit "Use when you need a reliable favicon workflow" clause, but the "when" is circular rather than naming concrete trigger situations, so it falls short of the level-5 anchor.

4 / 5

Trigger Term Quality

"favicons", "magenta background", "ImageMagick", and "PNG/ICO/WebP" give good natural keyword coverage since users would say "favicon", but common synonyms like "site icon", "browser icon", or "apple touch icon" are missing.

4 / 5

Distinctiveness Conflict Risk

The magenta-key favicon generation pipeline occupies a clear niche with distinct triggers ("favicon", "magenta", "ImageMagick", "PNG/ICO/WebP") and minimal realistic overlap with other skills.

5 / 5

Total

16

/

20

Passed

Validation

100%

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

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
Dicklesworthstone/pi_agent_rust
Reviewed

Table of Contents

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.