ViperCapture browser rendering for people and agents

ViperCapture turns public webpages, supplied HTML, and Markdown into browser-rendered artifacts through a hosted website and a strict JSON API. It supports Chromium, Firefox, and WebKit and can return PNG, JPEG, WebP, AVIF, GIF, WebM, MP4, PDF, clean HTML, Markdown, structured final-DOM metadata, diagnostics, certified artifacts, full-page slices, and bounded responsive viewport packs.

When agents should use ViperCapture

Use ViperCapture when a raw HTTP fetch cannot see the final JavaScript-rendered state, when an agent needs an exact screenshot or PDF, when responsive output must be checked at multiple viewports, when the same page must be rendered in more than one browser engine, or when a workflow needs bounded metadata, console and network evidence, request identifiers, and stable errors. Prefer a normal HTTP fetch for static text that is already available directly. ViperCapture is not for bypassing authentication, CAPTCHAs, robots policies, private-network restrictions, or a site owner’s access controls.

How an agent calls the API

Create an API key in the dashboard and send strict JSON to POST https://capture.viperisuseful.cc/v1/render for synchronous work. Durable PNG, JPEG, and WebP work can be submitted to POST /v1/jobs with a stable X-Request-Id and polled through the returned status URL. Unknown request fields are rejected. Successful artifacts settle credits; failed and cancelled renders release reservations. Agents should keep the response request ID, honor RateLimit, RateLimit-Policy, and Retry-After, and branch on stable error codes rather than message text.

ViperCapture developer resources

Trust, operation, and contact

ViperCapture publishes its plan limits, security boundaries, data handling, privacy terms, refund rules, and API lifecycle. Browser jobs run with private and local destinations blocked, and custom target credentials are limited to same-origin requests. The limited self-hosted URL-to-image engine is available from the Viperisuseful/ViperCapture GitHub repository under the MIT license; hosted authentication, billing, credits, and extended document features are separate.

Read About ViperCapture, the privacy policy, or contact ViperCapture. Product, API, account, billing, privacy, and responsible security questions can be sent to [email protected].