broken-authentication

This skill should be used when the user asks to "test for broken authentication vulnerabilities", "assess session management security", "perform credential stuffing tests", "evaluate password policies", "test for session fixation", or "identify authentication bypass flaws". It provides comprehensive techniques for identifying authentication and session management weaknesses in web applications.

Quality

76%

Does it follow best practices?

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Securityby

Critical

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tessl review fix ./skills/broken-authentication/SKILL.md

Quality

Content

57%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.

The content is a thorough, mostly actionable walkthrough of broken-authentication testing with clear phase sequencing, but it is verbose, inlines material that belongs in separate reference files, and omits the validation/verification checkpoints expected for destructive batch testing.

Suggestions

Add explicit validation checkpoints to the workflow (e.g., confirm each candidate finding is a true positive by reproducing it and ruling out false positives before documenting it as a vulnerability).

Extract the payload lists, cookie-flag tables, and worked examples into separate reference files under references/ and link to them one level deep, reducing the SKILL.md body to an overview.

Convert comment-pseudocode test blocks into concise executable commands or remove explanatory filler so every token earns its place.

Dimension	Reasoning	Score
Conciseness	The ~470-line body is mostly practical but includes many comment-pseudocode blocks (e.g., "# Test minimum length (a, ab, abcdefgh)", "# Step 1: Identify lockout threshold") and restated conceptual lists that could be tightened, falling between efficient and noticeably verbose.	3 / 5
Actionability	Provides concrete executable guidance such as a Hydra one-liner, Burp Intruder step sequences, a Python token-collection script, and specific HTTP requests, though several "tests" remain comment-style pseudocode lists with implicit success criteria.	4 / 5
Workflow Clarity	The ten numbered phases give a clear sequence, but this destructive/batch security-testing work lacks explicit validation checkpoints such as confirming findings are true positives before reporting, so workflow clarity is capped at 3 per the rubric.	3 / 5
Progressive Disclosure	No bundle files exist and all reference material (payload lists, cookie-flag tables, credential lists, worked examples) is inlined into a single ~470-line document that would benefit from being split into separate referenced files.	3 / 5
	Total	13 / 20 Passed

Description

95%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.

The description is strong: it clearly states what the skill does and when to use it, with comprehensive natural-language trigger phrases and a distinct niche. Its only minor weakness is that capabilities are expressed as user-facing triggers rather than concise capability verbs.

Dimension	Reasoning	Score
Specificity	Names the domain plus several concrete testing actions (credential stuffing, password policy evaluation, session fixation, authentication bypass), though they are framed as trigger phrases rather than crisp capability verbs with minor coverage gaps.	4 / 5
Completeness	Explicitly answers both "what" ("provides comprehensive techniques for identifying authentication and session management weaknesses") and "when" ("This skill should be used when the user asks to...") with concrete trigger phrases.	5 / 5
Trigger Term Quality	Comprehensive coverage of natural user phrases with synonyms and variations quoted verbatim ("test for broken authentication vulnerabilities", "assess session management security", "perform credential stuffing tests", "evaluate password policies", "test for session fixation", "identify authentication bypass flaws").	5 / 5
Distinctiveness Conflict Risk	Clear niche of broken authentication testing with distinct, specific triggers that are unlikely to fire for unrelated skills, minimizing conflict risk.	5 / 5
	Total	19 / 20 Passed

Validation

100%

Warnings & errors only

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: zebbern/claude-code-guide
Path: skills/broken-authentication/SKILL.md
Commit: 8428a63

Reviewed: about 2 hours ago

Table of Contents

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