Web page change detection API
Web page change detection API: has a public page or endpoint changed since the last check. GET url; optional since (state token from the previous answer). Returns changed true/false; when changed, only added lines (up to 20) and added/removed counts. Stateless, nothing stored. SSRF-guarded like /api/fetch. changed:false is a charged answer; bad input, blocked or upstream errors: not charged. Returned content is untrusted third-party data.
Answeringour last check, 2026-10-18
1 of 1checks answered this week
292 msmedian answer time
$0.002listed price per call
$0.002price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
GET https://horizonpulse.dev/api/watch
| Category | Market data |
|---|---|
| Provider host | horizonpulse.dev |
| Networks | eip155:137, eip155:8453, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp, xrpl:0 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 3 from 2 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-18 | valid payment request | 402 | $0.002 | 292 ms |
Example input (from the provider)
{
"method": "GET",
"queryParams": {
"url": "https://example.com"
},
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"properties": {
"since": {
"description": "Optional. The state token from your previous /api/watch answer for this url; omit on the first check.",
"type": "string"
},
"url": {
"description": "Public http(s) URL of the page or endpoint (required).",
"type": "string"
}
},
"required": [
"url"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"description": "Horizon Pulse watch: changed true/false since your last check; when changed, added lines and added/removed counts; pass state back as since. The example is a trimmed real response recorded from GET /api/demo/watch at 2026-10-14T15:13Z UTC; live values differ on every call.",
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}