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api-authentication

Secure API authentication with JWT, OAuth 2.0, API keys. Use for authentication systems, third-party integrations, service-to-service communication, or encountering token management, security headers, auth flow errors.

65

Quality

82%

Does it follow best practices?

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SecuritybySnyk

Passed

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SKILL.md
Quality
Evals
Security

Quality

Content

72%Weight 40%Scale 1-5

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

A well-structured, executable reference skill with excellent progressive disclosure and mostly lean content. Its main weakness is the absence of a sequenced workflow — it reads as a topical pattern library rather than a guided implementation process — plus minor verbosity in the middleware example and small coverage gaps (refresh endpoint, bcrypt example) in the body.

Suggestions

Add a short sequenced workflow (e.g., 1. pick method from the table, 2. implement token issuance/verification, 3. apply security requirements and headers, 4. test with an expired/invalid token) so the reference-style content also guides multi-step implementation.

Trim the redundant middleware checks (parts.length !== 2 and !token after the startsWith('Bearer ') validation) and the 'modern standards and best practices' filler phrase.

Include a minimal refresh-token endpoint and a bcrypt hashing snippet in the body (or explicitly point to them in the reference) to close the actionability gap around token lifecycle and password storage.

DimensionReasoningScore

Conciseness

The body is lean — a comparison table, two focused code blocks, and bullet lists with no re-explanation of concepts Claude already knows. Minor trimming is possible: 'using modern standards and best practices' is filler, and the middleware's redundant checks (parts.length !== 2, then !token, after already validating the 'Bearer ' prefix) spend tokens without adding information.

4 / 5

Actionability

The Node.js token generation and auth middleware code is executable and copy-paste ready, and requirements are concrete ('Hash passwords with bcrypt (cost factor 12+)', 'expiresIn: 15m'). Minor gaps: no refresh-endpoint implementation in the body (only in the reference file) and no password-hashing example despite naming bcrypt.

4 / 5

Workflow Clarity

The content is organized topically (methods table, implementation, requirements, headers, mistakes) rather than as a sequenced workflow; there is no ordered process (e.g., choose method → implement → harden → verify) or validation checkpoints. It stays at 3 rather than 2 because the table and sections make the single-topic material easy to follow, but it does not rise to 4 since no explicit sequence is presented.

3 / 5

Progressive Disclosure

The body is a clear overview with a well-signaled, one-level-deep reference: 'See [references/python-flask.md](references/python-flask.md)' is accompanied by a bullet summary of exactly what it contains, and the file exists with that content. The Node.js implementation stays inline while Flask variants are appropriately split out.

5 / 5

Total

16

/

20

Passed

Description

83%Weight 40%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.

A strong description with an explicit what-plus-when structure, specific named technologies, and natural trigger terms. Its only weaknesses are the noun-phrase style (no concrete action verbs), a few missing everyday synonyms like 'login' or 'auth', and slight overlap risk around the generic 'security headers' trigger.

DimensionReasoningScore

Specificity

'Secure API authentication with JWT, OAuth 2.0, API keys' plus 'token management, security headers' names several specific technologies and concern areas. It falls short of 5 because it is a noun-phrase inventory rather than a list of concrete actions (no verbs like 'implement', 'generate', 'rotate') and omits capabilities the body covers (e.g., session auth).

4 / 5

Completeness

It explicitly answers both parts: the 'what' ('Secure API authentication with JWT, OAuth 2.0, API keys') and an explicit 'Use for…' clause with concrete trigger phrases ('token management, security headers, auth flow errors'), matching the level-5 anchor pattern of what + when with concrete triggers.

5 / 5

Trigger Term Quality

'authentication systems, third-party integrations, service-to-service communication, token management, security headers, auth flow errors' gives good natural-keyword coverage a user would plausibly say. A few natural terms are missing (e.g., 'login', 'auth', 'sign-in'), keeping it below the comprehensive level 5.

4 / 5

Distinctiveness Conflict Risk

The JWT/OAuth/API-key niche is clear and mostly distinct from other skills, but 'security headers' and the broad authentication framing create minor overlap risk with general web-security or HTTPS/deployment skills, so it does not reach the minimal-conflict level 5.

4 / 5

Total

17

/

20

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.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

secondsky/claude-skills

Path

plugins/api-authentication/skills/api-authentication/SKILL.md

Reviewed

Table of Contents

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