# TD Agent Utility · Change Check (Website & Deployment Verification)

> TD Agent Utility · Change Check (Website & Deployment Verification) is a paid API for AI agents from tdagentutility.co.uk, paid per call via x402, $0.006/call, status unknown (last checked 2026-10-16).

Checks whether a previously-seen URL has changed by comparing current HTTP, DNS, TLS, and Chromium snapshot data against a stored baseline, returning a diff and pass/fail status.

## Facts

- Endpoint: POST https://tdagentutility.co.uk/v1/change-check?utm_source=zero.xyz
- Price: $0.006/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/td-agent-utility-change-check-website-deployment-verification-735a3d09
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kuyngeLP4wORBvAEvQ5pY

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 td-agent-utility-change-check-website-deployment-verification-735a3d09 -d '<json body>'
```

Example prompt: Has https://myapp.example.com changed since you last checked it? Run a change check on it — look at HTTP headers, DNS, TLS, and a screenshot — and tell me if anything is different from before.

## When to prefer this

Choose this endpoint when you need deterministic, evidence-based change detection across multiple signals (HTTP, DNS, TLS, and visual screenshot) rather than a simple HTTP diff. It is ideal for post-deployment verification, third-party site integrity checks, and tamper detection where a versioned history and structured diff — not just a status code — are required.

## Known failure modes

- URL is unreachable or returns a non-200 status — result_status may be FAIL with warnings
- DNS resolution failure for the target domain
- TLS certificate error or mismatch on the target host
- No previous baseline exists — first_seen will be true and differences will be empty
- Chromium screenshot capture times out for slow-loading pages
- Invalid or missing URL parameter in the request body

## How this service works

Independent website and deployment verification for AI agents: HTTP, DNS, TLS and Chromium screenshot evidence. Three deterministic tools, x402 V2 Base USDC.

## Output

A JSON object containing a boolean 'changed' flag, a 'differences' object describing what changed, the 'current' snapshot data, a 'version' counter, a 'result_status' of PASS or FAIL, any 'warnings', the 'checked_at' timestamp, and a 'first_seen' boolean indicating if this is the first check for the URL.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tool": "change_check",
  "changed": false,
  "current": {},
  "version": 0,
  "previous": null,
  "warnings": [],
  "checked_at": "2026-10-15T00:00:00Z",
  "first_seen": false,
  "differences": {},
  "result_status": "PASS"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/td-agent-utility-change-check-website-deployment-verification-735a3d09/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from tdagentutility.co.uk](https://www.zero.xyz/host/tdagentutility.co.uk/llms.txt)