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testland/atheris-python-fuzzing

Author and run Atheris - Google's Python coverage-guided fuzzer built on libFuzzer. Covers pip installation, atheris.Setup + atheris.Fuzz invocation, TestOneInput(data: bytes) target signature, FuzzedDataProvider for structured input, instrument_imports() / instrument_func decorators for coverage instrumentation, and libFuzzer-passthrough flags (-atheris_runs, -max_total_time, -dict). Use for fuzzing Python libraries - also supports CPython native-extension fuzzing.

80

Quality

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SecuritybySnyk

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Overview
Quality
Evals
Security
Files

Quality

Content

100%

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, fully actionable with executable examples, has a clear sequenced workflow plus anti-pattern checkpoints, and practices good one-level-deep progressive disclosure via well-signaled references.

DimensionReasoningScore

Conciseness

Lean body that assumes Claude's competence: no explanation of what fuzzing or coverage means, just the Atheris-specific mechanics, flags, and pitfalls. Repeated 'Per the Atheris README' sourcing is brief and purposeful, not padding.

3 / 3

Actionability

Every section gives executable, copy-paste-ready code and commands — pip install, a complete fuzz target, FuzzedDataProvider usage, real libFuzzer flag invocations, CI yaml, and crash reproduction — all concrete and specific.

3 / 3

Workflow Clarity

Sequenced authoring→running→parsing→CI flow with a dedicated Anti-patterns table (validation/pitfall checkpoints) and a reproducibility step; risky native-extension path is gated on matching ASan/libFuzzer builds.

3 / 3

Progressive Disclosure

Clear overview pointing one level deep to sibling references and plugins (sanitiser-integration-reference, corpus-management-reference, hypothesis-testing) with a dedicated References section; no nested/deep references and body is appropriately scoped.

3 / 3

Total

12

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12

Passed

Description

100%

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 specific, third-person, and includes explicit use-case triggers alongside concrete API surface and flags. It clearly answers both what the skill does and when to use it.

DimensionReasoningScore

Specificity

Lists many concrete capabilities: 'pip installation', 'atheris.Setup + atheris.Fuzz invocation', 'TestOneInput(data: bytes) target signature', 'FuzzedDataProvider', 'instrument_imports() / instrument_func decorators', and 'libFuzzer-passthrough flags' — multiple specific concrete actions.

3 / 3

Completeness

Answers both 'what' (the enumerated capabilities) and 'when' with an explicit trigger clause 'Use for fuzzing Python libraries', satisfying the explicit 'Use when...' requirement.

3 / 3

Trigger Term Quality

Includes natural terms a user would say ('fuzzing Python libraries', 'Python library', 'CPython native-extension fuzzing') alongside specific API keywords, giving good coverage of natural trigger language.

3 / 3

Distinctiveness Conflict Risk

Atheris-specific API names and 'Python coverage-guided fuzzer built on libFuzzer' carve a clear niche distinct from sibling fuzzers, unlikely to trigger for the wrong skill.

3 / 3

Total

12

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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

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Reviewed

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