Archive Compare
archive_compareWhat changed on a web page between two dates? Resolves the archived capture nearest each date (Internet Archive Wayback Machine, Common Crawl, Arquivo.pt), extracts the readable text of both, and returns a text-level diff: the segments removed and added, a similarity score, and both capture timestamps with their gaps from the requested dates. It diffs readable text, not markup, so a restyled page with the same words reads changed:false. Identical captures answer changed:false with the reason (same capture, identical content digest, or identical text), never an empty diff. A date with no capture within max_gap_days (default 30) answers status "no_capture", naming which side is missing and the nearest captures to it. Typical uses: how a privacy policy, terms of service, pricing or product page changed; whether a statement was on a page at a given time.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | The page address, e.g. "https://www.ftc.gov/policy-notices/privacy-policy". | |
| date_a | Yes | The earlier date, as YYYY-MM-DD (e.g. "2021-06-01"). | |
| date_b | Yes | The later date, as YYYY-MM-DD (e.g. "2024-06-01"). | |
| max_gap_days | No | Furthest a capture may be from each date and still be used, in days. Default 30, max 3650. |