DiffiCat

Takes a full-page screenshot of one URL, for example to see how a relaunched page or a mobile layout looks. Free 5 times, once per client address, no key needed. The PNG is taken at the given viewport width and returned inline when small, else as links.file to fetch with the jobToken. Call it for a one-off look at a page or a mobile-width check. Do not call it for pages a comparison job covers: the job already stored their screenshots. Example: { "url": "https://new.example/pricing", "viewportWidth": 375 }. Answers with jobId, jobToken, filename, url, dimensions, bytes, links.file and, on a free run, sample and allowanceRemaining.

Use when you deployed or edited a page and need to catch visual regressions and content changes: it compares the live URL with a baseline captured on the first call, a snapshot or a production URL, and answers the regressions. Free up to 40 pages, once per client address, no key needed.

Use when a staging or preview deploy should match production, or a migrated site its old one: it compares the pages of both origins and answers only the pages that are missing, changed or look different. Free up to 40 pages, once per client address, no key needed.

The prepaid balance and last 20 ledger entries of the key in the request’s Authorization: Bearer or X-DiffiCat-Key header; a human obtains one on the account page (/account), which a refusal’s nextSteps name. A Pro key also returns allowance (included pages shared with the web app, used, reset time) and overage (amount this period, cap). Each entry names its surface, web or api. Without a key, answers the remaining free allowance for your address. Free.

The finished report. Call it first with failedOnly: true and view: "digest": only the failed pages, each with its issues, diff percentage and largest regions, and a text line per page; summary covers every page. check_page and diff_deploy return the first regressed region's image; get_screenshot (?surface=full) fetches a region by filename. Without view, results are { path, status, failedChecks }; responseFormat: "detailed" returns per-check fields. offset and limit page through results (default 50, at most 5000; nextOffset is next); limit: 1 returns the summary alone; includeText: true adds the plain-text report. A change whose flakyShare is at least 0.5 is likely the page moving on its own: mask its fingerprint's element (visual.masks), not a regression. Call wait_for_comparison first. Free.

Waits until the job is completed, failed or cancelled, or timeoutSeconds pass, then answers status, progress and, once terminal, the summary (passed, failed, issuesBySeverity). On "running", call it again. Free.