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api-fuzzing-bug-bounty

Provide comprehensive techniques for testing REST, SOAP, and GraphQL APIs during bug bounty hunting and penetration testing engagements. Covers vulnerability discovery, authentication bypass, IDOR exploitation, and API-specific attack vectors.

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/api-fuzzing-bug-bounty/SKILL.md
SKILL.md
Quality
Evals
Security

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.

A dense, highly actionable payload and tool compendium with a clear five-step core workflow and responsible-use gating, but it is a monolithic single file that mixes overview content with reference material. It also carries removable padding and lacks explicit per-step validation checkpoints for a workflow whose operations are inherently risky.

Suggestions

Delete the sections that restate or pad rather than inform: the 'Purpose' section (duplicates the frontmatter description), the 'API Types Overview' table (SOAP/REST/GraphQL basics Claude already knows), and the generic 'When to Use' section.

Add explicit validation checkpoints to the Core Workflow steps, e.g., after each IDOR bypass attempt confirm the response actually contains another account's data before treating it as a finding, and re-verify authorized scope before testing write/delete methods.

Split reference-heavy material into one-level-deep bundle files (e.g., references/graphql.md for the GraphQL section, references/tools.md for the tools table) and signal them from SKILL.md to cut the token load of the main file.

DimensionReasoningScore

Conciseness

The payload/tool catalog mostly earns its tokens, but the 'Purpose' section restates the description verbatim, 'API Types Overview' explains SOAP/REST/GraphQL basics Claude already knows, and 'When to Use' is generic filler. This is more than minor over-explanation, so it sits at 'mostly efficient but could be tightened' rather than the 4 anchor.

3 / 5

Actionability

Concrete throughout: executable commands (kiterunner scan, curl introspection POST), specific payloads (IDOR wraps, XXE DOCTYPE, GraphQL batching), and a tools table with URLs. Not 5 because several entries are request fragments rather than runnable commands (e.g., '?url=Kernel#open → ?url=|ls', bare 'GET /api/users/1234 → GET /api/users/1235').

4 / 5

Workflow Clarity

Five clearly sequenced steps (recon → auth → IDOR → injection → methods) with a front-loaded confirmation gate and stop conditions, but per-step validation of findings is implicit at best (e.g., no 'verify the response actually contains another tenant's data before reporting IDOR'). This is a risky probing workflow, and the rubric caps clarity at 3 when validation checkpoints are missing.

3 / 5

Progressive Disclosure

Well-sectioned with headers and tables, but it is a ~450-line monolith with no external references: the tools reference, GraphQL deep-dive, and payload catalogs are inline material that belongs in separate reference files. Not 2 because in-file structure and navigation are genuinely good; not 4 because nothing is split out.

3 / 5

Total

13

/

20

Passed

Description

75%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 solid description that clearly states what the skill covers and the engagement context in which it applies, with concrete vulnerability-class naming and natural trigger terms. Its main weaknesses are the absence of an explicit 'Use when...' clause with concrete user phrases and some missing synonym variations.

DimensionReasoningScore

Specificity

Names the domain and several concrete actions ('vulnerability discovery, authentication bypass, IDOR exploitation, and API-specific attack vectors'), matching the 'several specific actions; minor gaps' anchor. Not 5 because coverage has gaps (no injection, GraphQL-specific, or enumeration mentions) and 'comprehensive techniques' is a mild over-claim.

4 / 5

Completeness

Both 'what' (testing techniques plus listed vulnerability classes) and 'when' ('during bug bounty hunting and penetration testing engagements') are present. Not 5 because the when lacks explicit 'Use when...' trigger phrases users would say; not 3 because the when is explicitly stated, not merely implied.

4 / 5

Trigger Term Quality

Good natural keyword coverage ('REST', 'SOAP', 'GraphQL', 'API', 'bug bounty', 'penetration testing') that users would actually say. Not 5 because common variations like 'API security', 'pentest', or 'endpoint testing' are missing.

4 / 5

Distinctiveness Conflict Risk

Clear niche (API-specific security testing for bug bounty) with distinct protocol-level triggers (REST/SOAP/GraphQL). Not 5 because general web-application pentest skills could plausibly overlap.

4 / 5

Total

16

/

20

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.

Validation — 15 / 16 Passed

Validation for skill structure

CriteriaDescriptionResult

frontmatter_unknown_keys

Unknown frontmatter key(s) found; consider removing or moving to metadata

Warning

Total

15

/

16

Passed

Repository

sickn33/agentic-awesome-skills

Path

skills/api-fuzzing-bug-bounty/SKILL.md

Reviewed

Table of Contents

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