behavior-preservation-checker
Verifies that a refactoring or transformation preserved observable behavior by comparing before and after execution, differential testing, or I/O capture. Use after a refactoring, after automated code transformation, before merging a structural PR, or whenever the claim is that two code versions do the same thing.
Install with Tessl CLI
npx tessl i github:santosomar/general-secure-coding-agent-skills --skill behavior-preservation-checker97
Quality
96%
Does it follow best practices?
Impact
Pending
No eval scenarios have been run
Discovery
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.
This is a well-crafted skill description that excels across all dimensions. It provides specific verification techniques, includes natural trigger terms developers would use, explicitly states both capabilities and usage scenarios, and carves out a distinct niche around behavior preservation verification that won't conflict with general testing or code review skills.
| Dimension | Reasoning | Score |
|---|---|---|
Specificity | Lists multiple specific concrete actions: 'comparing before and after execution', 'differential testing', and 'I/O capture'. These are distinct, concrete verification techniques. | 3 / 3 |
Completeness | Clearly answers both what (verifies behavior preservation via execution comparison, differential testing, I/O capture) AND when (explicit 'Use after...' clause with four specific trigger scenarios). | 3 / 3 |
Trigger Term Quality | Includes natural terms users would say: 'refactoring', 'transformation', 'structural PR', 'two code versions do the same thing'. These match how developers naturally describe behavior preservation concerns. | 3 / 3 |
Distinctiveness Conflict Risk | Clear niche focused specifically on behavior equivalence verification post-refactoring. Distinct from general testing skills or code review skills through its specific focus on before/after comparison and differential testing. | 3 / 3 |
Total | 12 / 12 Passed |
Implementation
92%Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.
This is a high-quality skill that provides comprehensive, actionable guidance for behavior preservation checking. The content is well-structured with excellent concrete examples, clear decision tables, and practical code snippets. The main weakness is that it's somewhat monolithic - the worked example and edge cases could potentially be split into separate files for better progressive disclosure.
| Dimension | Reasoning | Score |
|---|---|---|
Conciseness | The content is dense with actionable information and avoids explaining concepts Claude already knows. Every section earns its place - the comparison table, code examples, and edge cases all provide unique value without padding. | 3 / 3 |
Actionability | Provides executable Python code examples for differential testing and side-effect capture. The worked example walks through a complete real-world scenario with specific findings. The output format template is copy-paste ready. | 3 / 3 |
Workflow Clarity | Clear progression from cheapest to strongest approaches with explicit decision criteria. The worked example demonstrates the full workflow including how to interpret divergences. The 'Do not' section provides explicit validation checkpoints for avoiding common mistakes. | 3 / 3 |
Progressive Disclosure | Content is well-organized with clear sections and a logical flow from overview to details. However, it's a fairly long single document that could benefit from splitting the worked example or edge cases into separate files. The reference to 'semantic-equivalence-verifier' skill is good but is the only external reference. | 2 / 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.
Validation — 11 / 11 Passed
Validation for skill structure
No warnings or errors.
- Reviewed
Table of Contents
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