# ViewportWitness by Apex Labs – Cross-Viewport Browser QA API

> ViewportWitness by Apex Labs – Cross-Viewport Browser QA API is a paid API for AI agents from qa.honeygate.app, paid per call via x402, $0.12/call, status unknown (last checked 2026-10-14).

Submit a public URL and receive screenshots, accessibility findings, layout analysis, and a structured QA report across three browser viewports

## Facts

- Endpoint: POST https://qa.honeygate.app/v1/compare?utm_source=zero.xyz
- Price: $0.12/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/viewportwitness-by-apex-labs-cross-viewport-browser-qa-api-689f84c2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xTZjAiIxnMQ-afYxGjdZ_

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability viewportwitness-by-apex-labs-cross-viewport-browser-qa-api-689f84c2 -d '<json body>'
```

Example prompt: Can you run a full cross-viewport QA check on https://myshop.example.com — I want screenshots, accessibility findings, and a layout report across desktop, tablet, and mobile?

## When to prefer this

Choose this endpoint when you need a comprehensive, machine-readable QA report covering screenshots, accessibility, and layout across multiple browser viewports in a single API call. It is particularly well-suited for CI/CD pipelines, automated agency QA workflows, or regression detection when a baseline job ID is available. Prefer it over single-viewport screenshot tools or manual accessibility checkers when cross-device consistency is the primary concern.

## Known failure modes

- Invalid or non-public URL returns a 4xx validation error
- Payment not provided or rejected on live service returns a 402 Payment Required
- Baseline job ID not found returns a 404 error
- URL times out or is unreachable during rendering causes job failure
- Private/localhost URLs are rejected as not publicly accessible
- Rate limiting or quota exceeded returns a 429 error

## How this service works

Machine-facing browser QA API. Submit a public HTTPS URL and receive screenshots, accessibility findings, layout analysis, and a structured report across three browser viewports. x402 payment is required per report on the live service; see /.well-known/x402 for current payment options. Self-hosted instances can run in test mode without payment.

## Output

Returns a job ID, status (queued), a poll URL to retrieve the completed report, and payment mode. Once the async job completes, the full report includes screenshots, accessibility findings, layout analysis, and viewport comparison results across three browser sizes (typically desktop, tablet, and mobile).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "format": "uri",
   "example": "https://example.com",
   "description": "Public HTTPS URL to check"
  },
  "baselineJobId": {
   "type": "string",
   "format": "uuid",
   "description": "Completed, unexpired ViewportWitness check job used as the visual baseline."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "id": "550e8400-e29b-41d4-a716-446655440000",
  "status": "queued",
  "pollUrl": "/v1/checks/550e8400-e29b-41d4-a716-446655440000",
  "paymentMode": "production"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/viewportwitness-by-apex-labs-cross-viewport-browser-qa-api-689f84c2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from qa.honeygate.app](https://www.zero.xyz/host/qa.honeygate.app/llms.txt)