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fact-checker

Verifies factual claims in documents using web search and official sources, then proposes corrections with user confirmation. Use when the user asks to fact-check, verify information, validate claims, check accuracy, or update outdated information in documents. Supports AI model specs, technical documentation, statistics, and general factual statements.

60

Quality

70%

Does it follow best practices?

Impact

No eval scenarios have been run

SecuritybySnyk

Advisory

Suggest reviewing before use

Optimize this skill with Tessl

npx tessl skill review --optimize ./fact-checker/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

39%

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

The skill has a well-structured workflow with good validation checkpoints and user approval gates, but is severely bloated with information Claude already knows (source evaluation, query construction, handling ambiguity). The content would benefit enormously from being split into a concise SKILL.md overview with supporting reference files, and from removing explanations of concepts that are basic knowledge for an LLM.

Suggestions

Cut at least 50% of the content by removing sections Claude already knows: source evaluation hierarchy, good vs poor query examples, handling ambiguity guidelines, and the limitations section. These are general reasoning skills, not task-specific knowledge.

Extract 'Search best practices,' 'Special considerations,' and 'Examples' into separate reference files (e.g., SEARCH_GUIDE.md, EXAMPLES.md) and link from the main SKILL.md to improve progressive disclosure.

Add concrete tool invocation syntax for the web search step — show the actual search tool call format rather than just describing what to search for.

Remove the 'Next Step: Export Verified Content' section which cross-promotes other skills and adds no value to the fact-checking workflow itself.

DimensionReasoningScore

Conciseness

The skill is extremely verbose at ~250 lines. It explains obvious concepts like what constitutes 'good queries' vs 'poor queries,' how to evaluate sources (Claude already knows this), and includes lengthy sections on handling ambiguity, numerical precision, and limitations that Claude inherently understands. The 'When to use' trigger phrases, subjective content skip list, and source evaluation hierarchy are all things Claude already knows. Many sections could be cut by 70%+.

1 / 3

Actionability

The workflow steps are reasonably concrete with a comparison table format, status codes, and a report template. The Edit tool example is executable. However, much of the guidance is procedural description rather than executable code — the search strategy is descriptive, the examples are process summaries rather than concrete demonstrations, and there's no actual search tool invocation syntax shown.

2 / 3

Workflow Clarity

The workflow is clearly sequenced with 5 explicit steps, a progress checklist, and critical validation checkpoints — particularly the explicit 'wait for user approval before making changes' gate in Step 5, post-edit verification, and a quality checklist at the end. The feedback loop of showing the report and waiting for confirmation before destructive edits is well-handled.

3 / 3

Progressive Disclosure

The entire skill is a monolithic wall of text with no references to supporting files. Content like the detailed source evaluation guidelines, search best practices, special considerations, and examples could easily be split into separate reference files. Everything is inline, making the skill unnecessarily long for the SKILL.md overview level.

1 / 3

Total

7

/

12

Passed

Description

100%

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 is a well-crafted skill description that excels across all dimensions. It clearly articulates specific capabilities (verification via web search, proposing corrections), provides comprehensive trigger terms in an explicit 'Use when...' clause, and carves out a distinct niche that is unlikely to conflict with other skills. The inclusion of supported content types adds helpful specificity without being overly verbose.

DimensionReasoningScore

Specificity

Lists multiple concrete actions: 'verifies factual claims', 'using web search and official sources', 'proposes corrections with user confirmation'. Also specifies supported content types: 'AI model specs, technical documentation, statistics, and general factual statements'.

3 / 3

Completeness

Clearly answers both 'what' (verifies factual claims using web search, proposes corrections) and 'when' (explicit 'Use when...' clause listing multiple trigger scenarios). Also specifies scope of supported document types.

3 / 3

Trigger Term Quality

Includes strong natural trigger terms users would say: 'fact-check', 'verify information', 'validate claims', 'check accuracy', 'update outdated information'. These cover common variations of how users would phrase such requests.

3 / 3

Distinctiveness Conflict Risk

The combination of fact-checking, web search verification, and correction proposal creates a clear niche. The specific trigger terms like 'fact-check', 'validate claims', and 'check accuracy' are distinct from general document editing or search skills.

3 / 3

Total

12

/

12

Passed

Validation

100%

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

Validation11 / 11 Passed

Validation for skill structure

No warnings or errors.

Repository
daymade/claude-code-skills
Reviewed

Table of Contents

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