counterexample-generator

Generate concrete counterexamples when formal verification, assertions, or specifications fail. Use this skill when debugging failed proofs, understanding why verification fails, creating minimal reproducing examples, analyzing assertion violations, investigating invariant breaks, or diagnosing specification mismatches. Produces concrete input values, execution traces, and state information that demonstrate the failure.

1.10x

Quality

73%

Does it follow best practices?

Impact

85%

1.10x

Average score across 3 eval scenarios

Securityby

Passed

No findings from the security scan

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Run	Type	Date	Status
baseline vs usage-spec With / without context 7 months ago Completed	With / without context	7 months ago	Completed

Eval run

019cc492-f8eb-751f-a5cd-c3bcdb5d0eb1

Run 7 months ago

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Repository: ArabelaTso/Skills-4-SE
Path: skills/counterexample-generator/SKILL.md
Commit: 4f38503

Evaluated: 7 months ago
Agent: Claude Code
Model: Claude Sonnet 4.6

Table of Contents

Debugging a Failing Bank Account Verification Investigating a Bounded Queue Specification Failure Counterexample Analysis for a String Processing Library

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