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Web Freshness Fingerprint Observer
x402
Web Freshness Fingerprint Observer is a paid API for AI agents from 149-28-140-63.nip.io, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).
Fetches a public HTTP(S) URL and returns a timestamped SHA-256 content fingerprint along with HTTP metadata for change detection and verification.
Price / call$0.005
Success—
StatusUnknown
How this service works
Pay-per-request agent service providing timestamped SHA-256 fingerprints of public HTTP(S) resources.
Output
A JSON object containing the observed URL, its SHA-256 content fingerprint, HTTP status code, final URL (after any redirects), the ISO 8601 timestamp of observation, content type, and content length in bytes.
Example use cases
Legal page change detection
“Check https://acme.com/privacy-policy right now and give me a content fingerprint — I want to compare it against the SHA-256 I recorded last month: a3f1c9d2e8b47056f1234567890abcdef1234567890abcdef1234567890abcd.”
Public asset integrity audit
“Verify that the file at https://releases.myapp.io/latest/installer.dmg still matches the expected SHA-256 hash b94d27b99f6d5479a7da7263a6d5c3f2e1b08421ae0f6d44c57d9e8c4f2a9d1 — tell me the observed timestamp too.”
Third-party API uptime snapshot
“Observe https://status.stripe.com and return the current content fingerprint and HTTP status code so I can log the state of their status page right now.”
Technical details
Endpoint
POSThttps://149-28-140-63.nip.io/v1/execute/web.freshnessWhen to prefer
Choose this endpoint when you need a neutral, timestamped proof of what a public URL served at a specific moment — particularly for change detection pipelines, content integrity audits, or verifying that a resource matches a known fingerprint. Prefer it over manual HTTP fetching when you need structured metadata (status, final URL, content type, timestamp) alongside the hash in a single call.
Side effects
- URL is unreachable or times out — service may return an error or non-200 status
- URL is private or requires authentication — returns a 401/403 status with limited metadata
- Redirect loops cause the fetch to fail — final_url may differ unexpectedly
- SSL/TLS certificate errors on HTTPS URLs may cause fetch failure
- Content is dynamically generated so SHA-256 differs on every fetch even without meaningful change
- Provided expected_sha256 does not match the observed hash — mismatch is surfaced in result
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| url | string | Public HTTP(S) URL to observe. |
| expected_sha256 | string | Optional expected SHA-256 fingerprint. |
Output
Schema · Response
{
"type": "json",
"example": {
"result": {
"url": "https://example.com",
"sha256": "0000000000000000000000000000000000000000000000000000000000000000",
"status": 200,
"final_url": "https://example.com",
"observed_at": "2026-01-01T00:00:00.000Z",
"content_type": "text/html",
"content_length": 1256
}
}
}Tags
x402
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