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browser-extension-builder

Expert in building browser extensions that solve real problems - Chrome, Firefox, and cross-browser extensions. Covers extension architecture, manifest v3, content scripts, popup UIs, monetization strategies, and Chrome Web Store publishing.

54

Quality

61%

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SecuritybySnyk

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tessl review fix ./skills/browser-extension-builder/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

57%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 action-oriented with solid executable code across the core extension concerns, but it is held back by duplication/empty stubs, a lack of validation checkpoints in its workflows, and a monolithic single-file structure with no progressive disclosure.

Suggestions

Remove the verbatim description reprint and merge the overlapping 'Expertise' and 'Capabilities' lists into one to cut redundant tokens, and delete or fill the empty 'Architecture Patterns' stub.

Add explicit validation checkpoints to the publishing/build workflows (e.g. 'Load unpacked extension and verify in chrome://extensions', 'Validate manifest before zipping for the Web Store').

Move the detailed monetization, validation-check, and collaboration-workflow material into separate reference files and link to them from the overview to enable one-level-deep progressive disclosure.

DimensionReasoningScore

Conciseness

The body reprints the frontmatter description verbatim, the 'Expertise' and 'Capabilities' lists overlap heavily (Chrome extension APIs, Manifest v3, Content scripts appear in both), and stub headings like 'Architecture Patterns' carry only a 'When to use' line with no real content; these are unnecessary tokens that could be tightened. Not a 2 because the bulk is compact, executable code rather than padded concept explanation, and not a 4 because the duplication and empty stubs are noticeable.

3 / 5

Actionability

It provides concrete, copy-pasteable code for the manifest template, content scripts, storage API, async wrappers, payment integration, and feature gating, covering the common cases. Not a 5 because some areas are gaps — there is no actual popup.html/options.html example and the messaging pattern is shown only as an ASCII diagram rather than executable code.

4 / 5

Workflow Clarity

The Collaboration section lists sequenced workflows (Productivity Extension, AI Browser Assistant, each 6 steps), so a sequence exists, but there are no validation checkpoints or feedback loops (validate -> fix -> retry) and the steps are high-level. Not a 2 because the steps are coherent and ordered; not a 4 because checkpoints are entirely missing.

3 / 5

Progressive Disclosure

All content lives inline in a single ~250-line SKILL.md with no references/, scripts/, or assets/ bundle files; section headers provide structure, but content that would naturally be split (detailed monetization, validation checks, collaboration workflows) is inlined. Not a 2 because the headers give real navigable structure; not a 4 because no one-level-deep references exist to move bulk detail out of the overview.

3 / 5

Total

13

/

20

Passed

Description

66%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 clearly conveys what the skill covers with good natural trigger terms and a distinct niche, but it lacks an explicit 'Use when...' trigger clause, which caps completeness and leaves trigger guidance implicit.

Suggestions

Append an explicit 'Use when...' clause naming natural user phrases (e.g. 'Use when the user mentions a Chrome extension, Firefox addon, manifest v3, or browser extension').

Add common trigger synonyms like 'firefox addon' and 'webextension' to widen natural keyword coverage.

Tighten the opening 'solve real problems' phrasing toward concrete actions to push specificity from listing topics to listing actions.

DimensionReasoningScore

Specificity

The description lists several concrete capability areas (extension architecture, manifest v3, content scripts, popup UIs, monetization, Chrome Web Store publishing) with only minor coverage gaps, matching the score-4 anchor; not a 5 because items are topics/capabilities rather than a comprehensive set of specific concrete actions.

4 / 5

Completeness

It clearly states what the skill does ('building browser extensions... Covers extension architecture, manifest v3...') but has no 'Use when...' clause or equivalent explicit trigger guidance, which caps completeness at 3 per the rubric guidelines; not a 2 because the 'what' is clear and comprehensive.

3 / 5

Trigger Term Quality

It surfaces natural terms users say (browser extensions, Chrome, Firefox, manifest v3, Chrome Web Store, content scripts, popup UIs), giving good keyword coverage; not a 5 because common variations like 'addon'/'firefox addon' and file extensions are missing.

4 / 5

Distinctiveness Conflict Risk

Browser extension building is a distinct niche with specific triggers (manifest v3, Chrome Web Store) and minimal conflict risk; not a 5 because the broad 'architecture/popup UI' framing has minor overlap risk with generic frontend/web-app skills.

4 / 5

Total

15

/

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.

Validation15 / 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
sickn33/antigravity-awesome-skills
Reviewed

Table of Contents

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