# Slidingbox URL Drift Witness

> Slidingbox URL Drift Witness is a paid API for AI agents from drift.slidingbox.ai, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-12).

Checks whether a given URL has changed since its last observation, reporting differences in status, redirects, content type, page sections, and loaded scripts (including PCI DSS 11.6.1-relevant script fingerprinting).

## Facts

- Endpoint: GET https://drift.slidingbox.ai/v1/drift?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/slidingbox-url-drift-witness-c9fbc7f4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VdRdMNNwjtpDyr7DSC8Q7

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 slidingbox-url-drift-witness-c9fbc7f4
```

Example prompt: Has https://checkout.example.com/pay changed since it was last checked — specifically whether any scripts it loads have changed or if the page content is different?

## When to prefer this

Choose this endpoint when you need lightweight, non-invasive change detection for a URL without downloading the full page — especially for security-sensitive use cases like PCI DSS 11.6.1 script monitoring on payment pages, or when you want to track redirect drift, status changes, or content section changes over time across multiple callers. It is particularly well-suited for compliance workflows and tamper detection rather than full content retrieval or scraping.

## Known failure modes

- Invalid or malformed URL returns a validation error
- Non-HTTP/HTTPS URLs are rejected
- First-time observations return no change data (baseline only)
- Truncated responses for very large pages may yield incomplete fingerprints
- Network timeouts at the Cloudflare edge may delay or fail observation
- Pages requiring JavaScript or cookies may not reflect full rendered state

## How this service works

Has this page changed since it was last checked? Compares a URL with every earlier check of it by any caller: status, redirect target, content type, which sections changed, and whether the set of scripts it loads changed (the check PCI DSS 11.6.1 asks payment-page operators to run). Returns what was observed and from where, never the page itself. A page's first check is free.

## Output

Returns a JSON object indicating whether the URL changed across several dimensions (status, content, scripts, redirect target, content type), along with section-level diff counts, script count and fingerprint, content fingerprint, HTTP status, observation timestamp, vantage point details (Cloudflare colo, egress method), and a history summary (total observations, first seen, last changed). Does not return the page itself.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri",
       "maxLength": 2048,
       "description": "The http(s) URL to observe."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "url": "https://example.com/",
  "changed": {
   "status": false,
   "content": true,
   "scripts": false,
   "final_url": false,
   "content_type": false
  },
  "history": {
   "observations": 7,
   "first_seen_at": "2026-09-18T10:00:00.000Z",
   "last_changed_at": null
  },
  "vantage": {
   "colo": "SJC",
   "client": "fetch, no JavaScript, no cookies",
   "egress": "cloudflare-workers"
  },
  "sections": {
   "total": 12,
   "changed": [
    3
   ],
   "removed": 0
  },
  "observation": {
   "bytes": 1256,
   "scripts": {
    "count": 4,
    "fingerprint": "sha256:…"
   },
   "redirects": 0,
   "truncated": false,
   "normalizer": "v1",
   "http_status": 200,
   "content_type": "text/html",
   "content_fingerprint": "sha256:…"
  },
  "observed_at": "2026-09-19T10:00:00.000Z",
  "reason_codes": [
   "content_changed"
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/slidingbox-url-drift-witness-c9fbc7f4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from drift.slidingbox.ai](https://www.zero.xyz/host/drift.slidingbox.ai/llms.txt)