Verification

Token diff

Compare two design systems from live URLs — diff tokens added, removed, renamed, value-changed, scale drift, contrast drift, and structure delta. The only URL-scoped design-token diff engine.

Also serves as the diff engine inside /monitor (m08 token-set mutation detection). 8 emission checks plus score delta on both sites.

What it does

The compare engine fetches both URLs in parallel, extracts all CSS and :root custom properties from each, and computes a structured diff across 8 dimensions: token-added, token-removed, token-renamed (heuristic Levenshtein), token-value-changed, scale-stop-changed, contrast-drift-per-pair, structure-delta, and score-delta (runs /score on both URLs and diffs).

Scoring: 8 checks. PASS=1, WARN=0.5, FAIL=0. Score = (points/8) × 100. The compare score reflects diff completeness (did the engine produce a full diff), not design quality — design quality is the /score surface. The diff result itself is the product.