Workflow guide
A monitoring job needs more than a fresh screenshot if it must decide whether a public page changed. Attest Capture returns the artifact bytes, capture time and SHA-256 digest for each PNG, PDF or rendered HTML job. A workflow can store the last accepted digest, capture the same public URL again and compare the new digest. When the values differ, the workflow has a concrete signal that the rendered artifact changed and a pair of evidence receipts for review.
Consistency matters. Reuse the same format, full-page setting and viewport so avoidable rendering differences do not dominate the comparison. Schedule calls from your own job runner; Attest Capture exposes the capture endpoint but does not provide a built-in monitoring scheduler. Store the capture ID, timestamp, digest and evidence URL for each run, then send changes to a human or a separate diff process before taking consequential action. PNG is useful for visual inspection, HTML can support text-aware downstream comparison, and PDF can preserve paged output. Credit use is one for PNG or HTML and two for PDF.
A changed digest means the captured bytes differ. It does not explain why. Advertising, timestamps, rotating content, consent banners, fonts, network timing or other dynamic elements can produce a new artifact even when the meaningful policy or product information is unchanged. An unchanged digest shows that those captured bytes match, not that the underlying service, database or private content stayed the same. The renderer reaches public HTTP and HTTPS pages only; authenticated or private-network targets are blocked. Treat the digest as a dependable trigger for investigation, not as an autonomous judgement about material change.