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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.

Quality

68%

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SecuritybySnyk

Passed

No findings from the security scan

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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 strong on concrete, executable code spanning architecture, content scripts, storage, and monetization, but structural quality is undermined by verbatim duplicated sections, redundant capability lists, and absent workflow validation checkpoints. It is a monolithic file that would benefit from splitting detailed material into reference files.

Suggestions

Remove the verbatim-duplicated "Security boundaries" paragraph and duplicate "## Extension Monetization" heading (lines 244-258 appear twice), and merge the redundant "Expertise"/"Capabilities" lists into one.

Add validation checkpoints and error-recovery loops to the build workflows (e.g., verify the extension loads unpacked and test in both Chrome and Firefox before publishing), which would lift workflow clarity above 3.

Move the monetization details and Validation Checks into reference files (e.g., references/monetization.md, references/validation.md) with clearly signaled one-level-deep links from the SKILL.md overview.

DimensionReasoningScore

Conciseness

The bulk of the body is efficient, executable code, but there is notable waste: the "Security boundaries" section and the "## Extension Monetization" heading are each duplicated verbatim, the "Expertise" and "Capabilities" lists repeat each other and the description, and persona filler ("You extend the browser to give users superpowers") adds nothing. This sits between anchors 2 (several padded sections) and 3 (mostly efficient) since the core content is lean and the padding is concentrated in a few places.

3 / 5

Actionability

Concrete, largely executable artifacts are provided: a complete MV3 manifest template, a content script with readyState handling and an async message listener, storage wrappers that check chrome.runtime.lastError, and payment/feature-gating code. Minor gaps ("// Handle click", "// Run premium feature" placeholders, empty click handler in injectUI) keep it at anchor 4 rather than 5's fully copy-paste-ready bar.

4 / 5

Workflow Clarity

The two Collaboration workflows list coherent numbered sequences but include no validation checkpoints or error-recovery loops, and there is no end-to-end build workflow tying the pattern sections together. The "Validation Checks" section describes lint-style rules rather than workflow checkpoints, matching anchor 3 ('steps listed but validation gaps').

3 / 5

Progressive Disclosure

This is a monolithic ~390-line SKILL.md with no bundle files and no external references; monetization details, validation checks, and full API examples are inlined where an overview-plus-references design would split them out. Section headers do provide real structure, so it fits anchor 3 ('some structure... content that should be separate is inline') better than anchor 2's minimal structure, though the duplicated headings further hurt organization.

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.

A specific, domain-distinct description that clearly conveys what the skill covers, weakened by the total absence of a "Use when..." trigger clause and missing natural synonyms like "addon". Adding explicit trigger guidance would raise both completeness and trigger-term quality.

Suggestions

Add an explicit trigger clause, e.g. "Use when the user mentions browser extensions, Chrome extensions, Firefox addons, manifest v3, or publishing to the Chrome Web Store."

Include natural synonyms and variations users actually say, such as "add-on"/"addon" and "web extension", to improve trigger-term coverage.

Trim the vague filler "that solve real problems" and lead with concrete actions ("Build, debug, and publish...") to sharpen specificity.

DimensionReasoningScore

Specificity

The description lists several concrete capability areas ("extension architecture, manifest v3, content scripts, popup UIs, monetization strategies, and Chrome Web Store publishing") rather than vague language, though these read as topic areas more than parallel concrete actions. It sits between anchor 3 (only 1-2 actions) and anchor 5 (comprehensive parallel actions), matching anchor 4's 'several specific actions; minor gaps'.

4 / 5

Completeness

The 'what' is clearly stated (building Chrome, Firefox, and cross-browser extensions covering specific areas), but there is no "Use when..." clause or equivalent explicit trigger guidance anywhere in the description, which caps completeness at 3 per the judging guidelines. Not 4, since the 'when' is entirely absent rather than just under-specified.

3 / 5

Trigger Term Quality

Natural terms users would say are present: "browser extensions", "Chrome", "Firefox", "manifest v3", "Chrome Web Store". Common variations like "addon"/"add-on", "web extension", or "Firefox addon" are missing, which fits anchor 4 ('good keyword coverage; a few natural terms missing') rather than 5's comprehensive synonym coverage.

4 / 5

Distinctiveness Conflict Risk

"Browser extensions... manifest v3... Chrome Web Store publishing" is a clear niche with mostly distinct triggers and only minor overlap risk with closely related skills (e.g., frontend or business/monetization skills via "monetization strategies"). It falls short of anchor 5, which pairs the niche with explicit trigger phrases.

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.

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

sickn33/agentic-awesome-skills

Path

skills/browser-extension-builder/SKILL.md

Reviewed

Table of Contents

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