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api-fuzzing-bug-bounty

This skill should be used when the user asks to "test API security", "fuzz APIs", "find IDOR vulnerabilities", "test REST API", "test GraphQL", "API penetration testing", "bug bounty API testing", or needs guidance on API security assessment techniques.

65

Quality

77%

Does it follow best practices?

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SecuritybySnyk

Critical

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tessl review fix ./skills/api-fuzzing-bug-bounty/SKILL.md
SKILL.md
Quality
Evals
Security

Quality

Content

65%

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

The body is an actionable, reference-dense API fuzzing playbook with concrete payloads and a clear core workflow. Its main weaknesses are length/redundancy, the absence of validation checkpoints in the workflow, and the lack of progressive disclosure via separate reference files.

Suggestions

Add explicit verification checkpoints to the Core Workflow (e.g., 'Confirm the IDOR by reading the response body for another user's data; capture a proof-of-concept') to lift workflow_clarity.

Split the GraphQL-Specific Testing section and the Tools Reference table into separate reference files (e.g., graphql.md, tools.md) referenced one level deep from SKILL.md to improve progressive disclosure.

Remove the redundant Quick Reference and Common API Vulnerabilities summary tables (or merge them) and deduplicate the SSRF coverage between Step 4 and Output Exploitation to tighten conciseness.

DimensionReasoningScore

Conciseness

Mostly efficient reference-style content (commands, payloads, tables) with little conceptual padding, but ~430 lines with redundant summary tables (Common API Vulnerabilities, Quick Reference, Tools Reference) and repeated coverage (SSRF appears in both Step 4 and Output Exploitation) keep it from being fully lean.

2 / 3

Actionability

Highly actionable with copy-paste-ready payloads and commands, e.g. {"id":[111]}, ?url=|ls, the XXE DOCTYPE entity, and `kr scan https://target.com -w routes-large.kite`.

3 / 3

Workflow Clarity

A clear Core Workflow sequence (Recon -> Auth -> IDOR -> Injection -> Method) is present, but there are no explicit validation/verification checkpoints such as confirming a finding or verifying impact, which caps the score.

2 / 3

Progressive Disclosure

Content is well organized into sections but lives entirely inline in one ~430-line SKILL.md with no bundle/reference files; material that could be split out (GraphQL testing, Tools Reference) is not progressively disclosed.

2 / 3

Total

9

/

12

Passed

Description

90%

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: third-person voice, explicit 'Use when' trigger clause, and a rich set of natural trigger phrases covering the API security testing niche. Its only weakness is that capabilities are conveyed as trigger phrases rather than a distinct enumerated capability list.

DimensionReasoningScore

Specificity

Names the API security domain and several concrete actions ("fuzz APIs", "find IDOR vulnerabilities", "test REST API", "test GraphQL"), but these read as trigger phrases rather than a comprehensive list of distinct capabilities the skill performs.

2 / 3

Completeness

Explicitly answers both what ("API security assessment techniques") and when ("This skill should be used when the user asks to...") with explicit triggers.

3 / 3

Trigger Term Quality

Excellent coverage of natural phrases a user would say, e.g. "test API security", "fuzz APIs", "find IDOR vulnerabilities", "API penetration testing", "bug bounty API testing".

3 / 3

Distinctiveness Conflict Risk

A clear API-security/bug-bounty niche with distinct triggers that are unlikely to fire for unrelated skills.

3 / 3

Total

11

/

12

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.

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
zebbern/claude-code-guide
Reviewed

Table of Contents

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