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x-frame-options

Use when reviewing HTTP response headers for clickjacking protection on any web application with authenticated user actions.

61

Quality

72%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

Fix and improve this skill with Tessl

tessl review fix ./skills/x-frame-options/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

70%

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

A well-structured, simple skill that appropriately offloads detail to a single real reference file and includes a verification step. The main weakness is mild redundancy in re-explaining the clickjacking concept and deferring all executable code to the reference.

Suggestions

Trim the duplicated clickjacking attack explanation from the opening paragraph or Quick Reference, since both restate the same idea.

Add one inline copy-paste header example (e.g. a one-line Nginx or CSP snippet) so the body is actionable without opening the reference.

DimensionReasoningScore

Conciseness

The body is lean and well-sectioned, but it re-explains the clickjacking attack concept Claude already knows (opening paragraph and Quick Reference both restate it) and the Check/Fix/Explain sections overlap somewhat.

2 / 3

Actionability

Gives specific header values ('X-Frame-Options: DENY', 'SAMEORIGIN', CSP 'frame-ancestors') and clear decision rules, but the actual executable server config lives only in the referenced rule.md rather than the body itself.

2 / 3

Workflow Clarity

As a simple single-task skill the action is unambiguous, and the Code Review section adds an explicit verification directive ('verify them against the effective production-like response').

3 / 3

Progressive Disclosure

The body is a concise overview with a clearly signaled, verified one-level-deep reference ('see references/rule.md') for full implementation details and framework-specific code.

3 / 3

Total

10

/

12

Passed

Description

75%

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 is concise, uses the correct third-person trigger form, and clearly answers both what and when. It is somewhat under-specified on concrete actions and misses several natural trigger terms a user would mention.

Suggestions

Add concrete actions to the description, e.g. 'set X-Frame-Options DENY/SAMEORIGIN or add CSP frame-ancestors'.

Include the natural terms users actually say ('X-Frame-Options', 'frame-ancestors', 'CSP', 'iframe') to broaden trigger coverage.

DimensionReasoningScore

Specificity

Names the domain ('clickjacking protection', 'HTTP response headers') and one concrete action ('reviewing'), but does not list multiple specific actions like setting DENY/SAMEORIGIN or adding CSP frame-ancestors.

2 / 3

Completeness

Explicitly answers what ('reviewing HTTP response headers for clickjacking protection') and when ('Use when reviewing ... on any web application with authenticated user actions') with an explicit trigger clause.

3 / 3

Trigger Term Quality

Includes relevant natural terms ('clickjacking protection', 'HTTP response headers') but misses common variations a user would actually say such as 'X-Frame-Options', 'frame-ancestors', 'CSP', or 'iframe'.

2 / 3

Distinctiveness Conflict Risk

Targets a clear niche (clickjacking protection via security headers on authenticated web apps) with distinct triggers unlikely to overlap with unrelated skills.

3 / 3

Total

10

/

12

Passed

Validation

93%

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

Validation15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

metadata_version

'metadata.version' is missing

Warning

Total

15

/

16

Passed

Repository
thedaviddias/Front-End-Checklist
Reviewed

Table of Contents

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