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cross-origin-security

Use when reviewing scripts, client components, bundles, or runtime behavior related to Handle cross-origin requests securely. Inspect both source code and the browser execution path so fixes target the real bottleneck or bug.

60

Quality

70%

Does it follow best practices?

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SecuritybySnyk

Passed

No findings from the security scan

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tessl review fix ./skills/cross-origin-security/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

72%

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

The body is concise and well-structured as a review skill, with a clean single-reference pointer to a detailed, executable rule.md. Its weaknesses are the lack of inline executable code and the absence of explicit validation checkpoints in the body itself, both of which are deferred to the reference.

Suggestions

Include one short inline code snippet (e.g. an ALLOWED_ORIGINS postMessage guard) so the body is actionable without opening the reference.

Surface the verification checklist (especially the malicious-redirect test) directly in the body so review workflows have an explicit validation checkpoint.

Collapse the partially overlapping Check/Fix/Explain/Code Review sections to reduce redundancy with Quick Reference.

DimensionReasoningScore

Conciseness

The body is lean — terse Quick Reference bullets and short imperative sections — with no padding explaining what SOP or CORS fundamentally are; every section earns its place.

3 / 3

Actionability

Guidance names concrete items ('verify event.origin', 'Never set Access-Control-Allow-Origin: *', reject 'next', 'redirect', or 'callbackUrl'), but the body contains no executable code; copy-paste examples live only in the referenced file.

2 / 3

Workflow Clarity

Sections (Check, Fix, Explain, Code Review) are labeled tasks rather than a sequenced multi-step process, and the body has no explicit validation checkpoints; the verification checklist lives in the reference instead.

2 / 3

Progressive Disclosure

The body is a concise overview that signals a single one-level-deep reference ('see references/rule.md'), which exists and is well-organized, making navigation easy.

3 / 3

Total

10

/

12

Passed

Description

67%

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 includes an explicit 'Use when' trigger and states the capability, satisfying completeness, but its action verbs are generic and it omits the natural terms (CORS, postMessage, SameSite) users would most likely say. The broad review framing leaves some overlap risk with general JS skills.

Suggestions

Replace generic review verbs with concrete cross-origin actions, e.g. 'Validate postMessage origins, configure CORS allowlists, and reject open-redirect parameters'.

Add the natural trigger terms users actually say — 'CORS', 'postMessage', 'SameSite cookies', 'CSRF', 'open redirect' — to the description.

Tighten the 'related to Handle cross-origin requests securely' templating artifact so the capability reads as a clean third-person statement.

DimensionReasoningScore

Specificity

Names the domain and several review targets ('reviewing scripts, client components, bundles, or runtime behavior', 'Inspect both source code and the browser execution path'), but the actions are general review/inspection verbs rather than a comprehensive list of concrete operations.

2 / 3

Completeness

Both what ('Handle cross-origin requests securely') and when ('Use when reviewing scripts, client components, bundles, or runtime behavior related to...') are explicitly stated with a clear trigger clause.

3 / 3

Trigger Term Quality

'cross-origin requests' and 'scripts, client components, bundles, runtime behavior' are relevant natural terms, but common variations a user would actually say (CORS, postMessage, SameSite, CSRF) are absent.

2 / 3

Distinctiveness Conflict Risk

'cross-origin requests securely' is a recognizable niche, but the broad 'reviewing scripts, client components, bundles, or runtime behavior' framing could overlap with general JavaScript review skills.

2 / 3

Total

9

/

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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