CtrlK
BlogDocsLog inGet started
Tessl Logo

analyzing-typosquatting-domains-with-dnstwist

Detect typosquatting, homograph phishing, and brand impersonation domains using dnstwist to generate domain permutations and identify registered lookalike domains targeting your organization.

72

Quality

66%

Does it follow best practices?

Impact

Pending

No eval scenarios have been run

SecuritybySnyk

Advisory

Suggest reviewing before use

Optimize this skill with Tessl

npx tessl skill review --optimize ./skills/analyzing-typosquatting-domains-with-dnstwist/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Discovery

82%

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 strong description with excellent specificity and domain-relevant trigger terms that security professionals would naturally use. Its main weakness is the lack of an explicit 'Use when...' clause, which would help Claude know precisely when to select this skill. The description is concise, uses third person voice correctly, and occupies a very clear niche.

Suggestions

Add an explicit 'Use when...' clause, e.g., 'Use when the user asks about domain squatting, phishing domain detection, brand protection, or wants to run dnstwist against a domain.'

DimensionReasoningScore

Specificity

Lists multiple specific concrete actions: 'detect typosquatting, homograph phishing, and brand impersonation domains', 'generate domain permutations', and 'identify registered lookalike domains'. These are clear, actionable capabilities.

3 / 3

Completeness

The 'what' is well-covered (detect typosquatting, generate permutations, identify lookalike domains), but there is no explicit 'Use when...' clause or equivalent trigger guidance. The when is only implied through the description of capabilities.

2 / 3

Trigger Term Quality

Excellent coverage of natural terms users would say: 'typosquatting', 'homograph phishing', 'brand impersonation', 'lookalike domains', 'dnstwist', 'domain permutations'. These are the exact terms a security professional would use when needing this skill.

3 / 3

Distinctiveness Conflict Risk

Highly distinctive niche — domain security analysis using dnstwist is very specific and unlikely to conflict with other skills. The combination of typosquatting, homograph attacks, and the specific tool (dnstwist) creates a clear, unique identity.

3 / 3

Total

11

/

12

Passed

Implementation

50%

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

The skill provides highly actionable, executable Python code for a complete typosquatting detection workflow, which is its primary strength. However, it is significantly bloated with explanatory content Claude doesn't need (permutation technique descriptions, fuzzy hashing explanations, generic 'When to Use' bullets) and lacks integrated validation checkpoints between workflow steps. The entire skill could be cut to roughly half its size while preserving all actionable content.

Suggestions

Remove the 'Key Concepts' section entirely — Claude already understands DNS, fuzzy hashing, and domain permutation techniques. Move any truly novel configuration details into code comments.

Remove or drastically shorten the 'When to Use' section, which is generic and adds no actionable value.

Add explicit validation checkpoints between steps, e.g., verify dnstwist is installed and DNS is reachable before Step 1, validate JSON output structure before passing to Step 2's analysis.

Split the monitoring pipeline (Step 3) and export/takedown (Step 4) into separate referenced files to keep SKILL.md as a concise overview with the core scan-and-analyze workflow.

DimensionReasoningScore

Conciseness

Significant verbosity throughout. The 'Key Concepts' section explains DNS, fuzzy hashing, and permutation techniques that Claude already knows. The 'When to Use' section is generic filler. The overview paragraph restates what dnstwist does in excessive detail. The code examples are bloated with comments explaining obvious things.

1 / 3

Actionability

The code is fully executable, copy-paste ready Python with concrete subprocess calls, JSON parsing, risk scoring logic, and file export. All four steps provide complete, runnable functions with realistic parameters and output handling.

3 / 3

Workflow Clarity

The four steps are clearly sequenced (scan → analyze → monitor → export), but validation is only listed as a checklist at the end rather than integrated into the workflow. There are no explicit validation checkpoints between steps (e.g., verifying dnstwist output before analysis, checking DNS connectivity before scanning) and no error recovery feedback loops.

2 / 3

Progressive Disclosure

The content is a monolithic wall with ~250 lines of inline code that could be split into separate reference files. The references section links to external resources but the skill itself doesn't split content across files. Key Concepts, the full monitoring pipeline, and the export/takedown code could all be separate files referenced from a leaner overview.

2 / 3

Total

8

/

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.

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
mukul975/Anthropic-Cybersecurity-Skills
Reviewed

Table of Contents

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.