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safe-refactoring-rules

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Ensures all refactoring is deterministic, behavior-preserving, and non-breaking

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  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
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Source SKILL.md: https://github.com/Bottelet/DaybydayCRM/blob/HEAD/.claude/skills/safe-refactoring-rules/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/safe-refactoring-rules/. Do not write files or run scripts until I approve.

After I approve, install the complete skill folder, including required referenced files, into that project location. Verify it is discoverable, then tell me its actual invocation name and how to use it. Do not claim it is installed until you have verified it.

Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

Safe Refactoring Rules

Purpose

Ensure all refactoring is deterministic, non-breaking, and behavior-preserving.

This skill enforces how changes are made, not how the system is structured.

1. Behavior Preservation

  • Never change runtime behavior unless explicitly instructed.
  • Any refactoring must preserve observable outputs.
  • Moving code between layers must not alter execution results.

2. Existing Code Respect

  • Never overwrite an existing method if it already satisfies part of the requirement.
  • Extend existing implementations instead of replacing them.
  • Do not delete or rewrite working logic unless required for a fix.

3. Dependency Integrity

  • Always preserve constructor injection.
  • Never replace dependency injection with service locators (app(), resolve()).
  • Do not introduce new dependencies when existing ones suffice.
  • Do not change dependency graphs without explicit intent.

4. Public API Stability

  • Never change public method signatures unless all call sites are updated in the same change.
  • Avoid breaking changes at all costs.
  • Prefer internal adaptation over external contract modification.

5. Idempotency Requirement

  • Refactoring must be idempotent.
  • Running the same change twice must produce no further diff.
  • No duplicate logic, imports, traits, or methods may be introduced.

6. Uncertainty Handling

If any of the following is unclear:

  • intended behavior
  • service contract
  • domain rule
  • expected output

Then:

  • Stop immediately
  • Do not guess
  • Report ambiguity explicitly
  • Request clarification

7. Abstraction Reuse Rule (Local Scope Only)

This skill only enforces reuse during refactoring operations.

Global abstraction policy is defined in application-architecture-standard.

Before introducing:

  • Trait
  • Service
  • DTO
  • Transformer
  • Base class

Search for an existing implementation.

Reuse existing abstractions whenever practical.

Duplicate abstractions are architectural defects.

8. Scope Discipline

This skill does NOT define:

  • architecture layering (handled by application-architecture-standard)
  • testing strategy (handled by data-layer-contracts / filament-resource-testing)
  • security rules (handled separately if present)

It ONLY defines safe transformation rules.

9. Enforcement Priority

If this skill conflicts with others:

  1. application-architecture-standard
  2. domain-specific skills
  3. execution workflows
  4. this skill (always subordinate to architecture)