Mcp

Local-first visual regression testing SDKs for modern web applications.

This is the home of TestivAI. It contains everything you need to capture, diff, and report visual regressions fully locally — MIT-licensed, no account, no server.

See a live report → — a real TestivAI OSS report rendered in your browser, straight from CI. No install, no signup.

Why TestivAI?

Pixel-only visual testing drowns you in false positives — a font re-hint or an anti-aliasing shift across machines lights up as a "change," and you spend your time re-approving noise.

TestivAI pairs the screenshot with a snapshot of the page DOM (every adapter and the crawler capture one by default; the experimental testivai run sidecar does not) and, from most test-framework adapters, a digest of every element's computed styles. When pixels differ but the DOM and the computed styles are identical and the diff is small and scattered, the report labels the diff likely render noise instead of crying wolf. When the DOM and styles match but the diff sits in one area, it says that too: the style check covers a fixed list of properties, not size, overflow, transform or images, so that is a bad capture or a real change, not noise. It still shows the diff; it tells you what it most likely is. When only the styles changed, it says so: a style-only change is real. When the styles could not be compared, it says styles not compared and does not call the diff noise, because a stylesheet-only change is not ruled out. When the DOM actually changed, you see exactly what (2 added, 1 removed). That layered signal is the difference between a flaky test wall and a report you trust.

• Fully local, no account — captures, diffs, and a self-contained HTML report all stay on your machine.
• DOM + style-aware noise hint — tells likely render jitter from real changes, and catches the stylesheet-only case. When both captures carry an element map (the Playwright JS/TS, WebdriverIO, Selenium and Ruby adapters record one), an identical DOM with changed computed styles reads as "Styles changed on button.cta", never as noise. Without an element map on both sides (the testivai witness <url> crawler, playwright-python, playwright-java), computed styles are not compared, and an identical-DOM diff reads "styles not compared", not "likely render noise".
• Auditable masks & region-level diffs — exclude dynamic areas (selectors or coordinates) with the masked region hatched in the diff, and get "3 changed regions" with bounding boxes instead of a raw pixel percentage.
• Element attribution & exact shift detection — the report names which element changed ("div.card:nth-of-type(2) shifted +8px vertically — content unchanged") and spots the injected-banner case ("everything below y=80 moved +24px"), derived from layout, not pixel guesswork. No local-first tool does this.
• First-class adapters — Playwright (TS/JS and Python, Java experimental) and WebdriverIO, using each framework's native APIs; every language shares one set of baselines and one report.
• Mobile web, no extra package — Playwright device emulation works through the same witness() call: one project per device profile, baselines keyed per device automatically, and the DOM and computed-style attribution survives emulation, so a change behind a @media query is caught on mobile and correctly passes on desktop. See the mobile web guide.
• PR-native workflow — a GitHub Action posts the diff and approves baselines from a /testivai approve comment.
• No lock-in — MIT license, baselines live in your git, and results.json is a semver-governed public contract.