Enforces one rule: every code change must be presented as a unified diff (`diff -u` format) with 3 lines of context. No exceptions, even one-liners.
TRIGGER when: user requests a code modification — fix, refactor, update, replace, edit, patch, change, tweak, rename, rewrite, apply changes, modify this, edit the file, change this code, or explicitly asks for a diff — "show me the diff", "as a unified diff", "what changed", "show the patch", "/show-me-the-code". DO NOT USE when: producing a brand-new file from scratch (no context lines to diff against), or for non-code responses such as plans, explanations, architecture, or diagrams.
Installation
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Enforces one rule: every code change must be presented as a unified diff (`diff -u` format) with 3 lines of context. No exceptions, even one-liners.
TRIGGER when: user requests a code modification — fix, refactor, update, replace, edit, patch, change, tweak, rename, rewrite, apply changes, modify this, edit the file, change this code, or explicitly asks for a diff — "show me the diff", "as a unified diff", "what changed", "show the patch", "/show-me-the-code". DO NOT USE when: producing a brand-new file from scratch (no context lines to diff against), or for non-code responses such as plans, explanations, architecture, or diagrams.
Show Me The Code
Rule: every code change → unified diff (diff -u format). No exceptions.
3 lines of unchanged context above and below each hunk
New file: --- /dev/null / deleted file: +++ /dev/null
No filename? Use a/snippet.ts
Multiple files: one diff block per file
After the diff: optional 1–3 sentence why.
Example
Asked to "make total ignore negative prices", the entire response is the diff in diff -u
format — 3 context lines each side, file headers, hunk header — followed by one line of why:
--- a/src/cart.ts+++ b/src/cart.ts@@ -5,7 +5,7 @@ export function total(items: Item[]): number {
return items.reduce((sum, item) => {
- return sum + item.price;+ return sum + Math.max(0, item.price);
}, 0);
}
Clamping each price at 0 prevents a refunded line item from reducing the cart total below the legitimate sum.