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chrome-extension-developer

Expert in building Chrome Extensions using Manifest V3. Covers background scripts, service workers, content scripts, and cross-context communication.

45

Quality

48%

Does it follow best practices?

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SecuritybySnyk

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tessl review fix ./skills/chrome-extension-developer/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

51%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 skill provides a reasonable overview of Chrome Extension development with MV3, including useful concrete examples (manifest structure, message passing). However, it reads more like a reference cheat sheet than an actionable skill—it lacks sequenced workflows for its stated use cases (building from scratch, migration, debugging) and misses validation/verification steps. Some content explains things Claude would already know (e.g., basic security practices like avoiding eval).

Suggestions

Add a sequenced workflow for building an extension from scratch (e.g., 1. Create manifest → 2. Implement service worker → 3. Add content script → 4. Test with chrome://extensions → 5. Verify message passing), including validation checkpoints like loading the unpacked extension and checking for errors.

Add a brief migration workflow for MV2→MV3 with concrete steps and common pitfalls, since this is listed as a primary use case.

Remove or condense generic advice Claude already knows (e.g., don't use eval, validate external input) and replace with Chrome-extension-specific gotchas that are less obvious.

Consider referencing separate files for advanced topics like declarativeNetRequest rules, side panel API, or detailed debugging procedures to improve progressive disclosure.

DimensionReasoningScore

Conciseness

The 'Use this skill when' and 'Do not use this skill when' sections add moderate overhead. The instructions section is reasonably tight but includes some obvious guidance (e.g., 'Use Manifest V3' for a skill explicitly about MV3). The best practices section mixes well-known security advice (don't use eval) with Chrome-specific tips.

3 / 5

Actionability

Provides concrete, executable examples including a complete manifest.json and a working message-passing snippet. However, it lacks a content script counterpart example for the message passing, and the instructions are more like guidelines than step-by-step executable procedures. The troubleshooting section gives a concrete solution (chrome.alarms).

4 / 5

Workflow Clarity

There is no clear multi-step workflow for building or debugging an extension. The instructions are a flat list of guidelines rather than a sequenced process. For a skill covering extension development from scratch, migration, and debugging, the lack of any sequenced workflow with validation checkpoints is a notable gap.

2 / 5

Progressive Disclosure

The content is organized into logical sections (instructions, examples, best practices, troubleshooting) which provides decent structure. However, there are no references to external files for deeper topics like migration guides, advanced APIs (declarativeNetRequest, side panel), or detailed debugging procedures, and all content is inlined in a single file without clear pointers for expansion.

3 / 5

Total

12

/

20

Passed

Description

45%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 identifies a clear domain (Chrome Extension development with Manifest V3) and lists relevant technical areas, giving it reasonable distinctiveness. However, it lacks concrete action verbs describing what the skill actually does and entirely omits a 'Use when...' clause, making it harder for Claude to know when to select this skill over others. The description reads more like a topic expertise statement than an actionable skill description.

Suggestions

Add a 'Use when...' clause with trigger phrases like 'Use when the user asks about building Chrome extensions, creating browser plugins, writing manifest.json, or working with Chrome APIs'.

Replace topic listings with concrete actions, e.g., 'Scaffolds Chrome Extension projects, generates Manifest V3 configuration, implements background service workers, creates content scripts, and sets up message passing between extension contexts'.

Include common synonyms and variations like 'browser extension', 'Chrome plugin', 'manifest.json', 'chrome.* APIs', 'popup page' to improve trigger term coverage.

DimensionReasoningScore

Specificity

Names the domain (Chrome Extensions, Manifest V3) and lists several relevant concepts (background scripts, service workers, content scripts, cross-context communication), but these are topics/areas rather than concrete actions the skill performs. No verbs describing what it actually does (e.g., 'generates manifest files', 'scaffolds extension projects').

3 / 5

Completeness

Provides a partial 'what' (covers certain Chrome Extension topics) but has no 'when' clause at all. The description reads more like a topic summary than actionable guidance for skill selection. Missing a 'Use when...' clause caps this at 3 per guidelines, and the weak 'what' brings it to 2.

2 / 5

Trigger Term Quality

Includes relevant keywords like 'Chrome Extensions', 'Manifest V3', 'service workers', 'content scripts' that users might mention. However, it misses common variations like 'browser extension', 'Chrome plugin', 'popup', 'permissions', 'chrome.* API', or file references like 'manifest.json'.

3 / 5

Distinctiveness Conflict Risk

Chrome Extensions with Manifest V3 is a fairly specific niche that is unlikely to overlap with many other skills. The mention of specific concepts like service workers and content scripts helps distinguish it, though 'service workers' alone could overlap with general web development skills.

4 / 5

Total

12

/

20

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.

Validation10 / 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
administrakt0r/AI-Agents-Safe-Coding-Skills
Reviewed

Table of Contents

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