# Material Web Change Detection

> Material Web Change Detection is a paid API for AI agents from x402-gateway-production-1f21.up.railway.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-14).

Detects whether a webpage has changed by comparing its current content hash against a previously stored hash

## Facts

- Endpoint: POST https://x402-gateway-production-1f21.up.railway.app/commerce/material-web-change?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/material-web-change-detection-373f7e1a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_smBZCfWE1GU74CvVMoljP

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 material-web-change-detection-373f7e1a -d '<json body>'
```

Example prompt: Check if the page at https://example.com/pricing has changed since I last looked — my previous hash is a3f8c2d1e5b7a9f0c4e6d2b8a1f3c5e7d9b0a2f4c6e8d0b3a5f7c9e1d2b4a6f8.

## When to prefer this

Choose this endpoint when you need deterministic, hash-based detection of whether a specific webpage has changed, especially in automated pipelines that need to compare current state against a known prior snapshot. Ideal for AI agents monitoring competitor pages, regulatory content, pricing pages, or any URL where you have a stored previous hash. Prefer this over full-text scraping when you only need a changed/unchanged signal rather than the full page content.

## Known failure modes

- Invalid or unreachable URL returns an error or timeout
- previous_hash too short (under 32 chars) or too long (over 128 chars) rejected by schema validation
- URL returns non-200 HTTP status causing fetch failure
- Malformed JSON body results in 400 error
- Transient network issues cause request failure
- Page blocks automated access (e.g. Cloudflare) causing extraction failure

## How this service works

Machine-payable x402 utilities for hashing, Base64, UUID generation, unit and timezone conversion, realtime crypto market data, webpage/document extraction, URL-to-Markdown, metadata, RAG ingestion and deterministic website change detection.

## Output

Returns a JSON response indicating whether the webpage content has changed relative to the provided previous hash, along with the current content hash and optionally a diff or change summary, enabling deterministic website change detection.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "url",
      "previous_hash"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri"
      },
      "previous_hash": {
       "type": "string",
       "maxLength": 128,
       "minLength": 32
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "status": "ready"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/material-web-change-detection-373f7e1a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-gateway-production-1f21.up.railway.app](https://www.zero.xyz/host/x402-gateway-production-1f21.up.railway.app/llms.txt)