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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.

37

Quality

34%

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

The canonical home for this skill is browser-extension-builder in sickn33/agentic-awesome-skills

SKILL.md
Quality
Evals
Security

Quality

Content

14%Scale 1-3

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

This skill provides some useful code snippets (manifest template, content script patterns, storage API usage) but suffers from significant structural problems. It's bloated with redundant sections (expertise/capabilities lists, role description, collaboration boilerplate) while missing critical workflow guidance — there's no clear path from 'start' to 'published extension' with validation steps. The content reads more like a reference dump than an actionable skill guide.

Suggestions

Add a clear end-to-end workflow: create project → write manifest → implement features → load unpacked at chrome://extensions → test → fix errors → package → publish, with explicit validation checkpoints at each stage.

Remove redundant sections: consolidate 'Expertise' and 'Capabilities' into a single brief list or remove entirely; cut the 'Role' narrative and 'Collaboration'/'Delegation Triggers' boilerplate.

Split content: move detailed code patterns (content scripts, storage, monetization) into separate reference files and keep SKILL.md as a concise overview with links.

Add practical testing/debugging guidance: how to load an unpacked extension, inspect the service worker, check chrome.runtime.lastError, and use Chrome DevTools for extension debugging.

DimensionReasoningScore

Conciseness

Significant verbosity: the 'Role' description, 'Expertise' list, and 'Capabilities' list are redundant with each other and with the description. Sections like 'Collaboration', 'Delegation Triggers', 'When to Use', and 'Limitations' are boilerplate that don't add actionable value. The monetization section explains basic business concepts Claude already knows. The 'Validation Checks' section is formatted verbosely with severity/message/fix patterns that could be a compact table.

1 / 3

Actionability

The code examples for manifest.json, content scripts, storage API, and payment integration are concrete and mostly copy-paste ready. However, there's no guidance on actually building/loading/testing an extension (no `chrome://extensions` instructions, no build commands), and the monetization code references undefined functions (getStorage, showUpgradeModal) without full context. The workflows in the Collaboration section are vague numbered lists without executable steps.

2 / 3

Workflow Clarity

There is no clear end-to-end workflow for building an extension from start to finish. The collaboration workflows ('Define extension functionality', 'Build popup UI with React') are abstract and non-actionable. There are no validation checkpoints — no instructions to load the extension, test it, check for errors in the console, or verify before publishing. The 'Validation Checks' section lists anti-patterns but doesn't integrate them into a development workflow.

1 / 3

Progressive Disclosure

The content is a monolithic wall of text with no bundle files or external references. Everything is inline — the manifest template, content scripts, storage patterns, monetization, validation checks, and collaboration patterns are all in one file with no clear navigation structure. There's no separation of quick-start from advanced topics, and no references to supporting files.

1 / 3

Total

5

/

12

Passed

Description

54%Scale 1-3

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 identifies a clear niche (browser extension development) with good keyword coverage that would help Claude match user requests. However, it lacks explicit trigger guidance ('Use when...') and reads more like a topic list than a description of concrete actions. The use of 'Expert in' as the opening phrase is slightly promotional but uses third person framing.

Suggestions

Add an explicit 'Use when...' clause, e.g., 'Use when the user asks about building, debugging, or publishing browser extensions, or mentions Chrome extensions, Firefox add-ons, manifest.json, or content scripts.'

Replace the topic-listing style with concrete action verbs, e.g., 'Scaffolds extension projects, configures manifest v3, implements content scripts and popup UIs, prepares extensions for Chrome Web Store submission.'

DimensionReasoningScore

Specificity

Names the domain (browser extensions) and lists several relevant topics like 'manifest v3', 'content scripts', 'popup UIs', 'monetization strategies', and 'Chrome Web Store publishing', but these read more like topic areas than concrete actions. No action verbs like 'create', 'debug', 'configure' are used for most items.

2 / 3

Completeness

The description covers 'what' (building browser extensions, covering various topics) but completely lacks a 'Use when...' clause or any explicit trigger guidance for when Claude should select this skill. Per the rubric, a missing 'Use when...' clause caps completeness at 2, and the 'what' is also somewhat weak (topic listing rather than clear actions), so this scores a 1.

1 / 3

Trigger Term Quality

Includes strong natural keywords users would say: 'browser extensions', 'Chrome', 'Firefox', 'manifest v3', 'content scripts', 'popup UIs', 'Chrome Web Store', 'cross-browser'. These cover many common variations of how users would describe extension development needs.

3 / 3

Distinctiveness Conflict Risk

Browser extension development is a clear, distinct niche. The specific mentions of 'manifest v3', 'Chrome Web Store publishing', 'content scripts', and 'cross-browser' make it very unlikely to conflict with other skills.

3 / 3

Total

9

/

12

Passed

Validation

90%

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

Validation — 10 / 11 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

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

Warning

Total

10

/

11

Passed

Repository
popey/claude-code-skills
Reviewed

Table of Contents

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