# Website Change Evidence – Compare Live

> Website Change Evidence – Compare Live is a paid API for AI agents from website-change-evidence.inboxtzdjqv.workers.dev, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-21).

Fetches a live public webpage, computes citation-grade metadata and content hashes, and deterministically detects changes against a previously captured baseline snapshot.

## Facts

- Endpoint: POST https://website-change-evidence.inboxtzdjqv.workers.dev/v1/compare-live?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/website-change-evidence-compare-live-d987fb84
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_JPf4nhKlU2Kp5oOeA28QT

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 website-change-evidence-compare-live-d987fb84 -d '<json body>'
```

Example prompt: Check if the Amazon product page at https://amazon.com/dp/B09XYZ has changed since this snapshot — pay attention to whether the price phrase '$29.99' is still present, and compare it against the baseline object I captured yesterday.

## When to prefer this

Choose this endpoint when you need deterministic, citation-grade evidence of whether a specific public webpage has changed relative to a known prior state — especially for legal, compliance, or audit contexts where a cryptographic hash and metadata trail matter. Prefer it over generic scraping when you need both a live fetch AND a structured diff against a baseline in a single call, or when you need to assert the presence of specific phrases as part of the verification.

## Known failure modes

- URL is behind authentication or paywalled — returns fetch error or empty content
- Target URL returns non-200 status (404, 503) — change cannot be determined
- Baseline 'before' object is malformed or missing required fields — validation error
- Page uses heavy JavaScript rendering that the fetcher cannot execute — returns raw HTML without rendered content
- Network timeout fetching the live URL — returns timeout error
- Phrases array contains regex or unsupported syntax — match fails silently or errors

## How this service works

Read public webpages, capture citation-grade metadata and hashes, and detect live page changes deterministically.

## Output

Returns a structured object indicating whether the live page differs from the baseline snapshot, including content hashes for both versions, citation-grade metadata (title, fetch timestamp, canonical URL), a list of which target phrases were found or missing, and a deterministic change flag with diff details.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "url",
  "before"
 ],
 "properties": {
  "url": {
   "type": "string"
  },
  "before": {
   "type": "object"
  },
  "phrases": {
   "type": "array"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/website-change-evidence-compare-live-d987fb84/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from website-change-evidence.inboxtzdjqv.workers.dev](https://www.zero.xyz/host/website-change-evidence.inboxtzdjqv.workers.dev/llms.txt)