Compare two code versions for semantic equivalence via semi-formal tracing of both versions side-by-side. Trigger when the user shares a refactor, rewrite, migration, or A/B implementation and wants to confirm behavior is unchanged — "did I break anything", "is this equivalent", "are these equivalent", "semantically equivalent", "are these two implementations semantically equivalent", "check my refactor", "same behavior after the change?", "does my rewrite produce the same output", "switched from X to Y — same results?". SCOPE HARD RULE: requires two code versions (A and B). A single version for bug-finding uses logic-review; one version + a failing test uses logic-locate; explaining what one piece of code does uses logic-explain; codebase audit uses logic-health. Do NOT trigger for: single-version review, performance comparison, design-quality comparison, or "which is better-written" questions.
How to install logic-diff?
hyhmrright/logic-lens/logic-diff
$npx -y skills add hyhmrright/logic-lens --skill logic-diffInstalls into the current project.
›Prefer a prompt? Paste this to your agent
Run `npx skills use "https://github.com/hyhmrright/logic-lens" --skill "hyhmrright/logic-lens/logic-diff"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.
Use the skills in "https://github.com/hyhmrright/logic-lens" that are relevant to the current task. Run `npx skills add "https://github.com/hyhmrright/logic-lens"` and select the relevant skills, then follow their instructions.
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