browser-extension-builder

You extend the browser to give users superpowers. You understand the unique constraints of extension development - permissions, security, store policies. You build extensions that people install and actually use daily. You know the difference between a toy and a tool.

Quality

29%

Does it follow best practices?

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Securityby

Passed

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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

Quality

Content

52%Scale 1-3

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

The skill provides solid, executable code examples for core browser extension patterns (manifest, content scripts, storage, messaging), which is its main strength. However, it lacks a coherent development workflow—there's no guidance on how to load, test, debug, or publish an extension as a sequenced process. The content also includes some filler text and a vacuous 'When to Use' section that waste tokens.

Suggestions

Add a step-by-step development workflow: create project → write manifest → load unpacked in chrome://extensions → test → debug with DevTools → package → publish to Chrome Web Store, with validation checkpoints at each stage.

Remove the vacuous 'When to Use' section, the 'Role' paragraph (duplicates the description), and the 'Capabilities' bullet list (adds no actionable information).

Add concrete guidance on testing and debugging: how to reload the extension after changes, how to inspect the service worker console, and how to debug content scripts.

Split detailed reference content (e.g., cross-browser differences, store publishing checklist) into linked supplementary files to improve progressive disclosure.

Dimension	Reasoning	Score
Conciseness	The skill includes some unnecessary filler (e.g., the 'Role' paragraph repeats the description, the 'Capabilities' bullet list adds little value, 'When to Use' at the bottom is vacuous). The code examples themselves are reasonably lean, but the surrounding prose could be tightened significantly.	2 / 3
Actionability	The skill provides fully executable code examples: a complete manifest.json, content scripts with message passing, storage API usage with async/await wrappers, and UI injection code. These are copy-paste ready and cover the core extension development patterns.	3 / 3
Workflow Clarity	There is no sequenced workflow for building, testing, loading, or debugging an extension. The content presents isolated patterns without connecting them into a development process. There are no validation steps (e.g., loading unpacked extension, testing in browser, checking for errors in the console).	1 / 3
Progressive Disclosure	The content is organized into logical sections with headers, which helps navigation. However, it's a monolithic file with substantial inline code that could benefit from splitting (e.g., separate files for MV3 migration, cross-browser support, publishing workflow). The 'Related Skills' section hints at connections but doesn't link to deeper reference material.	2 / 3
	Total	8 / 12 Passed

Description

7%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.

This description reads like promotional copy rather than a functional skill description. It uses second person voice ('You extend...'), lacks concrete actions, omits a 'Use when...' clause, and relies on vague aspirational language instead of specific capabilities. It would be very difficult for Claude to reliably select this skill from a pool of alternatives.

Suggestions

Replace vague language with specific actions like 'Creates Chrome/Firefox browser extensions including manifest configuration, content scripts, background workers, popup UIs, and storage APIs'.

Add an explicit 'Use when...' clause with natural trigger terms such as 'Chrome extension', 'Firefox addon', 'manifest.json', 'content script', 'browser plugin', 'web store submission'.

Rewrite in third person voice (e.g., 'Builds browser extensions...' instead of 'You extend the browser...') to match expected skill description conventions.

Dimension	Reasoning	Score
Specificity	The description uses vague, aspirational language like 'give users superpowers' and 'know the difference between a toy and a tool' without listing any concrete actions. No specific capabilities like 'create popup UIs', 'handle content scripts', or 'manage background workers' are mentioned.	1 / 3
Completeness	The 'what' is extremely vague (extends the browser) and there is no 'when' clause or explicit trigger guidance. The description reads more like marketing copy than functional guidance for skill selection.	1 / 3
Trigger Term Quality	The only natural keyword is 'extension' and 'browser'. It misses critical trigger terms users would say like 'Chrome extension', 'Firefox addon', 'manifest.json', 'content script', 'popup', 'background script', '.crx', 'web store', or specific browser names.	1 / 3
Distinctiveness Conflict Risk	The mention of 'browser extension', 'permissions', 'store policies' does carve out a somewhat recognizable niche, but the vagueness means it could overlap with general web development skills. It's not as generic as 'helps with code' but lacks the precision to be clearly distinct.	2 / 3
	Total	5 / 12 Passed

Validation

90%

Warnings & errors only

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

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning

	Total	10 / 11 Passed

Repository: administrakt0r/AI-Agents-Safe-Coding-Skills
Path: skills/browser-extension-builder/SKILL.md
Commit: 7520423

Reviewed: ~15 hours ago

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