version-diff-summariser

Version Diff Summariser

What This Skill Does

Takes two versions of the same text — a before and an after — and produces a plain-English summary of every meaningful change: what was added, cut, reworded, restructured, and why each change is likely to matter editorially.

When To Use This Skill

• After an editor returns a marked-up draft and you want to understand the full scope of revisions quickly
• When handing a revised piece to a second editor who was not involved in the first round and needs to be brought up to speed
• During collaborative writing when two people have worked on the same section independently and you need to reconcile the differences
• When preparing a correction or update to a published article and you want a clear record of what changed for your corrections log
• Before a legal or compliance review, to document the changes made between draft stages

What You Need To Provide

Required: Both versions of the text, clearly labelled. Paste Version A (original) first, then Version B (revised), separated by a clear divider such as --- VERSION B ---. Optional: A brief note on who made the changes and why (e.g., "editor tightened for length" or "legal flagged the third paragraph"). This context lets the assistant frame the summary more accurately.

How the Assistant Approaches This

1. Reads both versions carefully, mapping the structure of each — paragraphs, sentences, key claims — to understand what belongs to what.
2. Identifies every category of change: deletions (content removed), additions (new content), rewrites (same idea, different words), structural moves (content shifted to a new position), and register or tone shifts (same meaning, changed level of formality or emphasis).
3. Produces a layered summary: a one-paragraph overview of the overall direction of the edit, followed by a change-by-change breakdown. Each item in the breakdown notes what changed, where it appears, and why the change is likely to matter — editorially, factually, or legally.