# Signal Forge Studio - Offer Change Check

> Signal Forge Studio - Offer Change Check is a paid API for AI agents from signalforgestudios.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-17).

Takes a snapshot of a public URL's offers, prices, CTAs, and headlines, then detects changes from a previously established baseline.

## Facts

- Endpoint: POST https://signalforgestudios.com/x402/offer-change-check?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signal-forge-studio-offer-change-check-24d583b4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6Qk9elOTI9Om0_yBnWXIh

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 signal-forge-studio-offer-change-check-24d583b4 -d '<json body>'
```

Example prompt: Can you take a snapshot of https://signalforgestudios.com/products and check whether the offers, prices, or CTAs have changed from the last baseline I set?

## When to prefer this

Use this endpoint when you need a lightweight, on-demand check of whether a specific public URL's offers, prices, CTAs, or headlines have changed since a previously established baseline. Ideal for online sellers, marketers, or agents that need point-in-time change detection without setting up continuous background monitoring infrastructure. Best when the caller manages their own snapshot history.

## Known failure modes

- URL is inaccessible or returns a non-200 status — snapshot cannot be captured
- Page requires authentication or blocks automated access — content may be empty or incomplete
- No prior baseline exists — first call creates a baseline rather than comparing
- HTML content is too large and gets truncated — some offers or prices may be missed
- Dynamic JavaScript-rendered content may not be captured if the crawler does not execute JS

## How this service works

Signal Forge Studio makes printable wall art and small digital kits for online sellers.

## Output

Returns a JSON object indicating the change status (e.g. 'baseline_created' or changes detected), a list of detected changes, and a full snapshot of the URL including offers, prices, CTAs, headlines, final URL, capture timestamp, and whether HTML was truncated. Note: the caller is responsible for retaining snapshots; no background monitoring is performed.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "status": "baseline_created",
   "changes": [],
   "snapshot": {
    "url": "https://example.com",
    "ctas": [],
    "offers": [],
    "prices": [],
    "version": 1,
    "final_url": "https://example.com",
    "headlines": [],
    "captured_at": "2026-09-22T00:00:00Z",
    "html_truncated": false
   },
   "limitations": [
    "Caller retains snapshots. No background monitoring."
   ]
  },
  "meta": {
   "example_only": true
  },
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signal-forge-studio-offer-change-check-24d583b4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from signalforgestudios.com](https://www.zero.xyz/host/signalforgestudios.com/llms.txt)