# PyFile Agent Web Change Detector

> PyFile Agent Web Change Detector is a paid API for AI agents from pyfile-agent.taile3ff35.ts.net:10000, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Computes the SHA-256 hash of a web page or JSON body and compares it against a baseline hash to detect changes, with optional JSON path extraction for monitoring specific fields.

## Facts

- Endpoint: GET https://pyfile-agent.taile3ff35.ts.net:10000/data/watch
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pyfile-agent-web-change-detector-db572112
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VuoLtmVe6AMG5evKuOt66

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 pyfile-agent-web-change-detector-db572112
```

Example prompt: Check if the content at https://example.com has changed since my baseline hash abc123def456... and let me know if there's a difference.

## When to prefer this

Use this endpoint when you need stateless, lightweight change detection for a web page or a specific field within a JSON API response. It is ideal when you already have a baseline SHA-256 hash and want to know if the content has changed without storing state server-side. Prefer this over full-scraping solutions when you only care about whether content has changed, not what it changed to, especially for narrow JSON field monitoring like prices or counters.

## Known failure modes

- Target URL is unreachable or returns an error — hash cannot be computed
- Invalid or malformed json_path causes extraction failure
- Baseline hash not provided — comparison not performed, only current hash returned
- URL returns dynamic headers or timestamps causing false positives in body hashing
- Rate limiting or blocking by the target server

## How this service works

SHA-256 of a page or JSON body + change detection vs a baseline hash. Stateless monitoring. Add &json_path=a.b.0 to extract and watch a single JSON field (price, counter). ?url=https://example.com&baseline=<sha256>&json_path=bitcoin.usd

## Output

Returns the current SHA-256 hash of the fetched URL's body (or of the extracted JSON field value if json_path is provided), along with a boolean or signal indicating whether the hash matches the provided baseline. If baseline differs, indicates a change has been detected.

## 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",
     "properties": {}
    }
   }
  },
  "output": {
   "type": "object"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/pyfile-agent-web-change-detector-db572112/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from pyfile-agent.taile3ff35.ts.net:10000](https://www.zero.xyz/host/pyfile-agent.taile3ff35.ts.net%3A10000/llms.txt)